Electric conversion: Project ForkenSwiift

[Silveredwings]

So, apparently the easy way to tell if a motor has neutral brush timing is to simply run it in both directions. If it runs faster in one direction, the brushes are advanced against that direction. Good thing we have 2 motors. Makes a comparison relatively easy.
Hook 'em together and see which one wins. :D

[MetroMPG]

Hoo ha! That's a good one :)

[philmcneal]

omg wow i'm so jealous... i really want an EV for my short trips ... oh man when I visit Toronto can I see this baby? Maybe even encourage me to work on my own EV! Man if I can build a simple EV that would seat four and would give me AT LEAST 30 km range per charge oh man I would be drooling all over it.

Your experience is truly appreciated! I hope your EV runs! Man now your tanks will truly rock because you'll never have a cold trip ever again in your Gas Geo!

SUPER JEALOUS!!!!!

[MetroMPG]

omg wow i'm so jealous... i really want an EV for my short trips ... oh man when I visit Toronto can I see this baby?
Sure thing, Phil. But I'm closer to Ottawa than Toronto :) You'd have to give me about 10 days notice to drive it to Toronto!

Maybe even encourage me to work on my own EV! Man if I can build a simple EV that would seat four and would give me AT LEAST 30 km range per charge oh man I would be drooling all over it.
You know there's a pretty active EV association in Vancouver. You could probably see some cars and get advice: http://www.veva.ca

Man now your tanks will truly rock because you'll never have a cold trip ever again in your Gas Geo!
May not work out that way. Just like the bicycle cargo trailer (http://www.gassavers.org/showthread.php?t=2170) , the EV is going to displace even more local driving where I consistently get better MPG than highway trips. The Blackflea tank averages are probably going to go down when the ForkenSwift goes on the road.

[MetroMPG]

Pulled the motor out again this evening -

[Silveredwings]

Pulled the motor out again this evening - a 5 minute job. How cool is that?
It couldn't be much cooler if it removed itself. In fact, if you ... er, um, forget what I said, bad idea. :)

Then we reassemble and test the "new" CCW motor RPM against "stock" CW RPM of sister motor - to determine if the brushes are neutral or not. Hoping they are (it'll save time). Should have compared RPM of both motors in stock form before all this, but I wasn't being very scientific.
Exactly what I was thinking (I know, big help ain't I).

It sounds great, I'll be watching.

[MetroMPG]

Well, we tested the motor today in both

[Silveredwings]

I read that it's actually possible to overspeed series wound motors if you run them w/o a load even though speed limits current flow. I would think the comm timing could have a huge effect on how the field and armature fluxes interact. I have no personal experience though.

[MetroMPG]

You're right about overspeeding a se

[MetroMPG]

The EV list folks seem to be leaning tow

[Silveredwings]

Great info.

[MetroMPG]

The motor guru has spoken.

[DaX]

Neat photos of motor guts!

[MetroMPG]

Futzed with the brush position

[Silveredwings]

Wicked cool! (as they say around here)

[SVOboy]

Mehbe I'll start saving immediately, hmmm...

What an inspiration!

[MetroMPG]

Also been reading up on motor "red lines".

[DaX]

Wow. That's amazing...I never knew you could blow a motor up like that! Like he said...good thing his friend wasn't troubleshooting under the car when it happened. Glad he got it fixed though...I bet it was $!

[Silveredwings]

I bet it was $!
...but not like throwing a rod in an ICE. :)

[The Toecutter]

Damn, I need to start posting on the EV list again. Finals are over, so I have time to do that again. I've missed sooooo much.

[MetroMPG]

[quote=Metrompg almost 2 weeks ago] Prediction! ... The

[MetroMPG]

It's

[The Toecutter]

Props to you man. Now I need to get off my *** and get mine going!

[MetroMPG]

Yeah, start a conversion thread. Keep me company here.

[The Toecutter]

I would, but I have no digital camera to show you guys pics.

But I assure you, there will be such a thread(and a website) eventually. And of the car's antics when the conversion is finished.

The EV list will certainly be the first to hear about it. Speaking of which, John Wayland is probably wondering where in the hell I've been! Ahh, to have 12 hours a day to devote to the internet again...

[omgwtfbyobbq]

omgz pimpness MetroMPG! :D

[DaX]

Haha, great video!

[MetroMPG]

Miscellany:

[MetroMPG]

On the motor red line question - got another reply from the Guru:

[Silveredwings]

Hey Darin, that's some great progress you're making.

I'd love to answer your question about the excel chart formatting but I don't have the file handy. I've unsuccessfully tried to recreate it but I'm currently out of town limping along on a Win98 porta-drone. If it makes you feel any better, it took me a while to get excel to cooperate. I can send it to you when I return home at the end of the week.

[MetroMPG]

AS

[SVOboy]

Whatever happened to september, that's all I want to know.

[MetroMPG]

September flew by in a blur of laziness and lack of motivation, I guess. :o

[MetroMPG]

[quote=MetroMPG]I believe controllers "charge"

[DaX]

Is it weird that I'm having a public conversation with myself?

You're not really...I'm doing a lot of head-nodding down here in Georgia.

[MetroMPG]

OK. Continue head-nodding...

Tried and failed again to get my eBay golf cart controller

[MetroMPG]

Man, my tinker time this weekend was

[SVOboy]

You can do it!

I wonder what the market is for custom EV conversions...you could start (another) business, :p

[MetroMPG]

Here's an interesting thing: that Youtube video I made of the motor spin-up has been watched over 500 times.

[MetroMPG]

Think I just discovered wh

[MetroMPG]

Got the EV-1 controller

[Silveredwings]

Excellent. :thumbup:

[CO ZX2]

Got the EV-1 controller to work. :thumbup:

Couldn't have done it without help - a couple of basic mistakes in my wiring (no surprise there). More to come...

Attaboy, Metro. I knew you could do it. I have been sending you good luck telepathic messages for 2-3 days. Do you have snow tires for that baby?

[DaX]

Got the EV-1 controller to work. :thumbup:

Couldn't have done it without help - a couple of basic mistakes in my wiring (no surprise there). More to come...

SWEET!

[MetroMPG]

Some more excellent controller news: I got the Cursit

[MetroMPG]

Whoops, missed this...

Do you have snow tires for that baby?
As a matter of fact, it's currently wearing the Blackfly's snows! I had to put them on it to get it through the safety check. :rolleyes:

[MetroMPG]

could be useful for comparing the efficiency of the 2 electronic controllers.

[Silveredwings]

Maybe you could modify the meter with a heated needle and then run some thermal paper past it while driving... j/k :D

But seriously, if you had a way to make periodic voltage readings with your laptop, you could effectively record the current at intervals by reading the voltage across the shunt (that's what the meter does). Depending on what other measurements you recorded at the same times, you could build some interesting data to play with (like vehicle speed, braking, battery voltage, SOC, etc).

There must be a cornicopia of A-to-D devices you can plug into an RS232 port with which you can take voltage recordings.

[MetroMPG]

Good ideas. Something like this?

http://www.rentron.com/Volt-Meter.htm

It would satisfy the nerd in me to drive both the cheapest AND most instrumented NEV in existence.

[MetroMPG]

Or a DMM with an RS232 output:

http://cgi.ebay.com/Mastech-PC-RS232-Auto-Range-True-RMS-Digital-Multimeter_W0QQitemZ190066444723QQihZ009QQcategory Z25412QQrdZ1QQcmdZViewItem

Too expensive for Project Forkenswift, but I didn't even know they existed until you suggested it.

[Silveredwings]

That looks like it would work for a single channel metric. :thumbup:

I'd be very surprised if you'd want to stop there with only the amperage over time w/o reference to what else is simultaneously going on. I was thinking of maybe a 4-channel or 8-channel multiplexed A/D. I'm sure I've tripped over things like that but now that I want one, I'd have to go digging. :confused:

EDIT (second try): the example (http://www.rentron.com/Volt-Meter.htm) above uses the ADC0831 (http://manuales.elo.utfsm.cl/datasheet/national/htm/nsc01950.htm) single-channel 8-bit A/D converter chip. Also in the same family are ADC0834 (4-channel) and ADC0838 (8-channel). The 8-channel can be configured as either 8 directly addressed inputs or 4 differential inputs. That latter may become necessary if you want to measure things on both the high voltage side as well as the 12V system. You definately don't want to make the grounds of those 2 systems common to each other.

[MetroMPG]

PS - did you get the Healey going yet?

[Silveredwings]

No but thanks for asking. BTW, your progress inspires me every day. :thumbup:

Now that I'm nearly done with the holidaze (family-shared illnesses notwithstanding), I expect to get back to it soon. :)

[Silveredwings]

That site also has an example (http://www.rentron.com/four-channel-ad.htm) using the chip for which they're selling the firmware & tools that implements a 4-channel A/D voltage logger. That chip is actually an 8-bit microprocessor with the A/D, and a small amount of program memory built in. It may even have voltage conversion buffers required to convert serial communication to true RS232 (I'm not sure).

In contrast, the 8051 (http://www.rentron.com/project02.htm) is the chip used in many ECUs (like Honda) and is powerful enough to be useful independent of a PC. It's a faster 8-bit microprocessor, with 4 built-in 8-bit I/O ports but no built-in A/D chip. For that, you'd probably use something like the ADC0838. Serial I/O would be optional but you'd probably want to use one in order to program/debug/data-dump the thing.

[The Toecutter]

Instrumentation is nice and all, and perfect for your application, but I'm going to try to keep it to a minimum in my conversion. I want an EV that will make people's loins ache, and not a rolling science project. Imagine the thought of rolling around in the ghettos of St. Louis in one dope ****ing ride, and that ride also being electric powered.

Silveredwings, you should convert the Healey. It might sound blasphemous, but the car has a lot going for it. It lends itself to extensive aeromods without greatly harming the aesthetic appeal, it's lightweight, and has small frontal area. not to mention, the battery room would be pretty decent with all the IC-related components removed.

Metrompg, I think you might be interested in Peter Ohler's EV palm pilot:

http://www.ohler.com/palm/EVDash.html

Victor Tikhonov simply uses a labtop to take his data, but he has all those fancy Siemens and Brusa components for his CRX.

Just the Siemens motor/inverter is more than 8 times the budget of your entire conversion. 107 HP AC motor/inverter combination, revs up to 9,700 rpm. This gives his CRX 0-60 mph in about 9 seconds or so and a theoretical top speed over 130 mph. He scored a set of Ovonic NiMH that supposedly give him about 150 miles highway range or so.

[Silveredwings]

Silveredwings, you should convert the Healey. It might sound blasphemous, but the car has a lot going for it. It lends itself to extensive aeromods without greatly harming the aesthetic appeal, it's lightweight, and has small frontal area. not to mention, the battery room would be pretty decent with all the IC-related components removed.
I've thought of that. In fact I think it would be too cool to convert one of the AHs I've seen with blown engines (though most of them end up modified with V8s (http://www.ntahc.org/modifiedhealeys/)). :cool:

I also know the racing history of Donald Healey's cars, and how successful of a roadster icon it became in America. I see both sides of it. I think I'd end up trading my time off between swapping in new running hardware into very very old rolling hardware vs. updating everything between the frame and the pavement. Even a GT6 is atleast a decade more advanced than the Healey whose running gear was designed in the early 1950s.

I'd actually rather send the Healey off to a good home and use it's accrued value to hack up something much easier to provision with parts and will handle as if it was made closer to this century. Maybe a Miata or Z3. I've gotten very spoiled with the handling and reliability of modern cars. Then the biggest limiting factor is battery technology, as it has been for the past 150 years. :rolleyes:

I know what you mean about that Siemens AC drive system: the ProEV Impreza has 2 of them in it for 270hp 4wd plus 35+ kW worth of Kokam Li-Ions. :thumbup:

[The Toecutter]

Battery technology has evolved a huge amount in the past 15 years. Due to politics and lack of automotive volume, EV builders just don't have ready access to an affordable battery capable of providing long range and long life.

I've thought of going to the dark side and lowering a smallblock Chevy into my Triumph, but I want to get off of using gasoline too badly. But the raw power of a V8 in a tiny little British car is something that commands my respect. After all, there's not many cheaper ways to get you down the 1/4 mile in under 11 seconds, while still getting over 20 mpg...

[Silveredwings]

I can't wait to get my hands on those new batteries. As for which car to modify, chosing my projects is as important as choosing my battles. :)

[MetroMPG]

I'm going to try to keep it to a minimum in my conversion. ASDF

[Silveredwings]

So I guess you won't be using this approach: :D
Well, I hope you don't drop $88,500 on your conversion. That might make all your coins ache. (sorry 'bout that)

[MetroMPG]

Coins... So funny. :D

I was startled when I saw the $$$ too. No danger of that happening with the Forkenswift: my coins are already aching, and I haven't spent 1% of that amount. (0.5% actually, since I'm only paying half.)

[The Toecutter]

Well, I hope you don't drop $88,500 on your conversion. That might make all your coins ache. (sorry 'bout that)

If I had $88,500 to spend on a conversion, I'd use an AC150 drivetrain, a three-speed paddleshift transmission with 3rd gear geared for 200 mph, a custom carbon fibre body designed for aerodynamic efficiency(< .18 Cd, < 1.4 square meter area), and about 500 kg of 18650 Li Ions. This would yield a roughly 900 kg race car with 0-100 kph < 4 seconds, 400 m drag race ~12 seconds, ~320 km/h top speed(in theory), ~700 km range at 120 km/h, and ~140 km range at 320 km/h... This cost would not factor my own labor, obviously.



That $88,500 conversion by Roland though was spend on the vehicle in total over its overship period. He's experimented with expensive fuel cells and prototype batteries in this car, and each incarnation of the car has had its upgrades factored into the cost.

[Silveredwings]

Well that's a horse of another color now isn't it?

[MetroMPG]

weekend update ...

1) Fixed (epoxied) the speedo cable boss I fubared back in post 340 (http://www.gassavers.org/showthread.php?p=32321&highlight=fubared#post32321). Installed the replacement cable from the red car (getting the cluster out was a bit of a pain). Then tested it: made the wheels go 25 km/h :p

2) Put oil back in the tranny ("previously enjoyed" 5-20 synth from the Blackfly :o) ... then noticed it was seeping around one of the axle seals. Crud. Last thing I want is an EV that leaves oily spots on the driveway. That's just too ironic for my tastes.

3) Dug up Jerry's nice clear circuit schematics over at http://evconvert.com. They're so easy to read for an electrical newb like myself. Got together with Ivan and we drew up the Forkenswift's schematic, v 1.0. I'll post it sometime.

4) Tranny & adapter plate are now properly fastened with good size nuts & bolts (no more wing nuts).

5) A friend donated about 20 feet of used 3/0 welding cable - it'll be great for making battery connections.

6) This week: want to pick up a battery load tester, and start looking for 6 or 8 surplus/used batteries. Starting with the forklift co that sold us the Baker.

[Silveredwings]

Excellent: 2 steps forward, 1 step back.

So it is with the Healey too. I put some gas in it with no leaks so far. The fuel pump doesn't suck (in this case that's bad). So it's either $275 from Moss or I tinker with it. The wife says "spend." I think a new one should play nicely with almost a grand in new SU carbs. :cool:

[brelandt]

Watched the DVD, "who killed the electric car" tonight.

I think my Sidekick would be a good canidate for a EV project as well.

Now all I have to do is go back and read all 400 plus posts to this thread!!!!!!

[Silveredwings]

I think my Sidekick would be a good canidate for a EV project as well.
I think I saw an older Sidekick/Tracker conversion for sale a while ago. I wonder if it's still around.

[The Toecutter]

I think my Sidekick would be a good canidate for a EV project as well.

If range at speeds over 30 mph isn't a serious concern, go for it.

[DaX]

I'm just curious - for wiring up an EV, would it be wise/economical/ludicrous to use Romex for the wiring? I know lack of flexibility would be a downside, but would there be any others?

[Silveredwings]

Can you get romex in 2/0 or 3/0 AWG? If not, it will heat up and maybe catch on fire. If you have to bunde it, how will you connect it to batteries and things?

[MetroMPG]

Watched the DVD, "who killed the electric car" tonight.
Me too. (Again.)

I think my Sidekick would be a good canidate for a EV project as well.
We actually started out watching for one of these as a host. Toecutter's right - only really suitable as a "town car" due to aerodynamics.

would it be wise/economical/ludicrous to use Romex
I'd never heard of Romex before you asked. I looked it up and it appears to be plastic sheathed cable. But is it structural cable or electrical? (good conductor?) Flexibility isn't necessarily a problem - you just have to plan more carefully. Some people use bent copper bus bars for battery interconnects.

[MetroMPG]

http://www.youtube.com/watch?v=2Ins29dqbac

[DaX]

http://forkenswift.com/offsite/first-curtis-power-up-youtu.jpg (http://www.youtube.com/watch?v=2Ins29dqbac)

http://www.youtube.com/watch?v=2Ins29dqbac

Nice! Is the 20 km/h in 1st gear? What do you estimate it will be with 48V?

I'm not sure what sizes Romex comes in, but I was wondering if it was good enough for a house (120V), will it be good enough for this (48V)? How many amps is the Forkenswift going to see? What's the max amp rating on typical romex? (general questions for anyone :))

[Silveredwings]

A quick check of ohms law (http://en.wikipedia.org/wiki/Ohm's_law) (and AWG sizes (http://www.bnoack.com/index.html?http&&&www.bnoack.com/data/wire-resistance.html)) tells me if you put only 15 HP into the motor on a startup (15HP x 746W/HP), you'll be cranking over 11kW through the wires. At 36 V, that'll require over 310 Amps. 12 guage wire in your house walls is great for a 15A circuit, but it has over 27 times the resistance of say 3/0 guage wire. That added resistance multiplies by the amperage and results in a voltage drop (and heat loss).

For example, 20' of 3/0 ga. copper is about 0.00124 ohms. At 310A, that drops about 0.38 V, or about 119W dissipated in the wire. With 12 ga. copper wire, the same length is 0.034 ohms and at 310A, that's 10.5V dropped and over 3kW dissipated (though this becomes a self limiting system about this point: the more resistance, the lower the current and HP output).

Resistance also goes up with temperature and that all your connections will add resistance losses as well so you want to minimize resistance wherever you can. Also, copper wire does work-temper as you bend it (not as bad as Al) and so goes up in resistance at those bends. It's small but cummulative. Solid wire is worse in this respect than stranded wire.

This is one reason why the more engineered EV designs go for higher voltage systems in order to keep peak current lower: fewer resistance losses in motors, wires and connections, lower weight conductors, etc. This is also why many people say that an EV's performance is more limited by the controller's capacity than the motor - as in what's the peak current capability of the controller?

YMMV.

[MetroMPG]

Also, copper wire does work-temper as you bend it (not as bad as Al) and so goes up in resistance at those bends. It's small but cummulative. Solid wire is worse in this respect than stranded wire.
Hmm - learned something new today. Thanks for the lesson.

[Silveredwings]

The forklift controller limit is in the neighbourhood of 400A, but it also has a bypass, which will feed full battery current to the motor under certain (logic) conditions.
That must be analogous to a tourque-converter lockup clutch. :) It does make a lot of sense. At those high amperages, the semiconductors are just ohmic switches dissipating a lot of loss because of their even slight resistances. If the duty cycle of the PWM gets close enough to 100%, it might as well use a relay (metal) instead of silicon.

EDIT: that should mean that the system should be more efficient at the equivalent of WOT.

BTW, silicon resistance goes down with temperature. That's why there have to be preset thermal or current limits or they will fuse together (read self-destruct). When you do overload a power transistor, you will be able to see glowing silicon a split second after it pops the lid off the device's case and a split second before it clouds the view with smoke. Don't ask me how I know this. :D

[Silveredwings]

Still, 9 HP is theoretically enough to go 55 mph in this car on level ground (assuming you don't run out of power before you eventually accelerate to that speed). What else am I missing?
That's a steady-state or straight and level cruise. I think your system's peak current limit will determine your acceleration rate and ability to climb hills. (edit: I mean that 9 hp may mean 0-50kmh in approximately 10 or 15 minutes :) ) - edit 2: when you hit the gas pedal, your laptop application can just show an hourglass, or better yet, one of those calendars with the individual date sheets blowing off in the wind. :D

[MetroMPG]

That must be analogous to a tourque-converter lockup clutch. :) EDIT: that should mean that the system should be more efficient at the equivalent of WOT.
Nice analogy!

[MetroMPG]

Thinking about EV hypermiling techniques: I wonder if the car will coast further in neutral or in gear when off the go pedal...

[brelandt]

Just showed my Landlord the "Who killed" DVD. He LOVED it.

Infact when I first walked over to his house he asked me if I wanted to sell my Sidekick. Asked why. He said to build an EV out of it!

I told him that when I get my Integra back that I had plans to do the same to it.

So he asked if I knew where he could get a Geo Metro? How weird is that was my first thought.

Anyhow ended up watching the movie again tonight with him.

That and with listening to him explain how the EV works and what parts to get I really got charged up (no pun intended) to start an EV project.

However I'm electrically retarded and will need a lot of training by a really patient teacher. Lucky for me he was a teacher at a local college in electronics and has the talent to put things into laymens terms for me.

[brelandt]

I just had to add something to this.

LAst year I was living in Atlanta working for a general aviation company. We were "cleaning" house and I was tasked to moving the heavier things like aircraft windshields and the like that the "girls" I was working with wouldn't move.

I remebered throwing out (recycling) two 160 pound electric motors from our massive air compressor system that ran all of the air tools in the hanger. I have no idea what the specs where on them but I'm sure they could have worked on an EV.

Just think of it. If I had been into EV's back then I would have saved myself $300 easily not to mention all of the 28V batteries I recycled as well. hell I even threw out a controller!!!!!!

Next time you see an avation company or heck even drive down to your local FOB see if they have any of these thing collecting dust? I'm sure since they have to track their spending they will be more than willing to just give them to you for free.

Also would a electric motor from a generator work? After hurricane Katrina hit my town there is bound to be a few old generators lying around?

[MetroMPG]

Sounds like you've got the ideal situation with your landlord being an electronics teacher.

[MetroMPG]

Schematic time...

[Silveredwings]

OK, now you're talking. I have some questions.
1. Are the the coils of the contactor solenoids intended to operate at 36 - 48V?

2. Are you connecting the 12V battery ground and the 36V battery grounds together? Or is only one connected to the body (I assume atleast the 12V gnd is or you'd have to rewire the rest of the car).

3. The controller looks as if it regulates only the negative connection to the motor. If the negative side of the battery is always connected to ground (once the neg contactor is closed) and the positive is always connected to the motor (once the positive contactor is closed), then there is a risk of any short (e.g. dropping a wrench) between ground and the negative motor connections throwing the motor into full power (serious lurch).

[brelandt]

Nope he did but it looks just like this one but baby blue......

http://www.austinev.org/evalbum/991

[MetroMPG]

1. Are the the coils of the contactor solenoids intended to operate at 36 - 48V?

Yes - they're out of the forklift. It only had 1 pack (no 12

[MetroMPG]

Brelandt: he's got a CitiCar/ComutaCar! Awesome. He's basically driving what I'm building. I probably would have bought one of those if there were any around here.

[Silveredwings]

that's what you call electrically isolated, right?
Yes.

But for that scenario to happen, someone would have to be pressing the go pedal (to close the pack +ve contactor) while I was dropping the wrench. Not too likely to be wrenching around under those circumstances.
Well, yes isolating the ground should greatly reduce such a risk. BTW contactors sometimes do stick.

4th question:
4. Does the pot box micro switch have a normally-closed (NC) position?
If so, you may be able to further mitigate accidental lurches the way Jerry does with that latching relay, though in your case, you'd may need to use a DPDT relay. Let me think about that.

[MetroMPG]

If I understand Jerry's setup, his pot box latching relay prevents the pack +ve contactor from closing if the ignition is switched on while the go pedal is pressed.

His approach is sort of equivalent to forcing you to depress the clutch before starting a manual, or pressing the brake to shift out of park.

I omitted that precaution.

[Silveredwings]

Right again. It does make sense to omit that interlock if you're the only one who will drive it. Some people (like my mother) have a tendency to step on the gas pedal when turning on a car - that can be bad since there's no engine that must first be started. I believe the interlock is required (in the US) of EV manufacturers but I don't think it applies here.

OK, so back to the ground issue. Your shematic shows the negative connections to the contactor coils with a "chassis ground" symbol but there is no place where that ground actually connects to the negative side of the 36V. I assume those connections go to the point just after the shunt.

I would put a small fuse (1A or less)) on the + side of both the voltmeter and the ammeter. It's just a precaution and won't affect their accuracy.

[Silveredwings]

Also you should fuse the controller +36V small wire, and the clock wire (it's better than having burned wires - see I do have a serious side :) ). The Ammeter fuse may not be needed but if the shunt ever comes loose, it'll save the meter from being fried.

Maybe like this?
http://www.gassavers.org/attachment.php?attachmentid=146&stc=1&d=1168401800

[MetroMPG]

Awesome - thanks.

OK, so maybe I should have an interlock. I never thought it was a problem, but if there's a law...

[MetroMPG]

PS - didn't realize I was mis-using the chassis ground symbol. Learned sumpin' new today! Just in time too - the day's almost over, here.

[Silveredwings]

OK, so maybe I should have an interlock. I never thought it was a problem, but if there's a law...
I think it's more of a dummy-proofer. A boss of mine once told me "you can't make anything foolproof because fools are so ingenious." :)

I seriously think a kill switch would more worthy of your time and more likely to be appreciated by first responders. Another place for an interlock is on any opening compartment that exposes the traction wiring - but then again good insulating covers may be better overall. Those kind of interlocks too often get defeated while the thing is in "R&D."

So essentially everything gets fused? Should I put a fuse inline with the potbox microswitch too?

Pretty much. Besides being a safety valve of sorts, it's also a way to disconnect parts of the circuit w/o putting switches everywhere. The potbox probably doesn't need a fuse because it's just a 'sense' circuit. The 5k pot varies from a dead short to 5,000 ohms and is just a voltage divider for the controller input. It shouldn't have much current flowing if all connections remain correct. Besides some controller internal malfunction, the only danger would come from some higher power wire coming in contact it. This is where the quality of your physical electrical connections will pay off in overall reliability.

Here's another question: someone asked why I was using pack voltage to control the main contactors. Do you happen to know if they'll work on 12v? Or will they just pull more current and get hotter?
It would be easier to wire if everything except 'power' was 12V but it depends on the parts themselves.

A 36 volt contactor coil energized with 12V won't pull more current because of the lower voltage (prob less) and thereby heat up, but there could be another problem with the lower V. If as you said, they came out of the forklilft as 36V devices, then 12V may not be enough to get them to close firmly. If they engage weakly, or worse chatter, then the power contacts will probably arc, self destruct, and otherwise ruin your day.

Also, if the correct V is 36V, then 48V into the contactor coils would entail more power draw and more heat, but I don't know if that's destructive. If it is and you still want to go to 48V or more, there are ways you could handle that with varying amounts of scope creep:
1. Just use a wire coming from the third battery (36V worth) for the contactor circuit. This one falls into the "if it's stupid and it works then it ain't stupid" category. It means assymetrical loading of the batteries but maybe only slightly.
2. Use an electronic regulator circuit to drop the 48V down to 36V for those coils (it's not as complicated as it sounds).
3. Change the contactors to 12V ones (prob the most expensive).

BTW, I'm pretty sure the small wire to the controller still has to be at full pack V.

[Silveredwings]

PS - didn't realize I was mis-using the chassis ground symbol. Learned sumpin' new today! Just in time too - the day's almost over, here.
Sometimes a circuit will have 2 different 'grounds.' Sometimes there is a chassis ground, and an earth ground. Sometimes they're just used to simplify 2 different circuit common points to reduce clutter in the drawing. In any case they usually each use a different symbol for clarity:
http://www.gassavers.org/attachment.php?attachmentid=147&stc=1&d=1168407500
In your case, the traction battery negative side isn't really a ground, especially since the negative side is the part that is regulated (chopped by the PWM). OTOH, the -12V is a true chassis ground since it's used throughout the car.

BTW, cars used to have positive ground - or in the Healey, "positive earth." The convention changed to negative ground to reduce the effects of electrolytic corrosion in the body.

[MetroMPG]

I seriously think a kill switch would more worthy of your time and more likely to be appreciated by first responders.

You mean like a big read panic button on the dashboard

[MetroMPG]

Battery news: just got off the phone with the company that sold us the forklift.

[DaX]

Floodie = wet cell?

[MetroMPG]

Yup. Flooded lead acid batteries, that need periodic watering to replace electrolyte lost during charging.

Golf carts, industrial floor sweepers, and most EV conversions use 6v floodies.

[Len Case]

Nope he did but it looks just like this one but baby blue......

http://www.austinev.org/evalbum/991

I was just browsing along seeing how things were going with Project Forkenswift and I clicked on the link and... THAT'S MY CAR.

That's so funny. :)

I just purchased it in December and while it does run, there are problems with it--the Forward/Reverse contactor spits blue-green flame in reverse and when I try to go forward at low speed it jumps like a jerky start in a clutch--if I press down the pedal more it evens out but apparently I can't use low speed.

With the problems I haven't tried taking it further than the end of the block so far.

[CO ZX2]

I was just browsing along seeing how things were going with Project Forkenswift and I clicked on the link and... THAT'S MY CAR.

That's so funny. :)

I just purchased it in December and while it does run, there are problems with it--the Forward/Reverse contactor spits blue-green flame in reverse and when I try to go forward at low speed it jumps like a jerky start in a clutch--if I press down the pedal more it evens out but apparently I can't use low speed.

With the problems I haven't tried taking it further than the end of the block so far.

Len. Welcome to GasSavers. Just stay right here. Metro is the GS EV man. He may be getting tired of his own problems and welcome a new one.

[MetroMPG]

Hi Len - that IS funny. Congrats on the C-Car purchase. A classic.

I don't want to chase you away, but for help with your contactor setup, have you checked in with the Yahoo C-Car group yet? Someone was describing a similar problem recently (the reverse problem, anyway) :

Burning up reverse is a common topic. It seems like everyone's reverse melts sooner or later. - source (http://autos.groups.yahoo.com/group/C-Car/message/4995)
http://autos.groups.yahoo.com/group/C-Car/

Fairly active group, and there are some schematics and other good info available in the "files" area.

I'd try there first for getting help - that's where the expertise hangs out. I'd be really interested in hearing your car's story though. I hope you'll post more here.

[Len Case]

Hi Len - that IS funny. Congrats on the C-Car purchase. A classic.

I don't want to chase you away, but for help with your contactor setup, have you checked in with the Yahoo C-Car group yet? Someone was describing a similar problem recently (the reverse problem, anyway)

Yeah, I've been lurking around on that list too, lots of good advice. I also went to my local electric vehicle association meeting and met some local EV experts who have offered to let me rummage through their spare parts to try to fix up my contactor--on the other hand I think I may just replace the contactor with a new one.

--Len

[MetroMPG]

I also joined a "local" EV association - great resource for suggestions & assistance. Sounds like you've got it under control.

What's the story of your C-Car purchase? Barn find?

[MetroMPG]

HA! Project Forkenswift is famous :D

AutoblogGreen discovered the YouTube videos and posted an item:

Don't know where these guys are located (their Web site isn't up yet) but their first two videos covering the electric conversion of Geo Metro are worth watching. The project is called ForkenSwift and the crew is using a hydraulic motor salvaged from a forklift. The first video showed a quick power-up using one battery. Now the team has added two more batteries and a controller from a 48-volt golf cart. They seem to know what they're doing and it looks like they've got a hit series out of their garage. Can't wait to see more of the conversion.

http://www.autobloggreen.com/2007/01/13/electric-car-conversion-on-a-beer-budget/

[SVOboy]

Have you pointed them to this thread or will your ite be up soon?

[MetroMPG]

I haven't pointed them here. Guess I should, eh? The site's pretty far down my to-do list.

Coincidentally, this week I suggested a story to ABG that got posted yesterday (EV milestones, 2006 (http://www.autobloggreen.com/2007/01/12/top-12-electric-vehicle-milestones-for-2006-as-selected-by-the/), from the EVDL).

[Len Case]

What's the story of your C-Car purchase? Barn find?

I've been interested in electric cars for a few years now and every now and then I would check the EV Tradin' Post (http://www.austinev.org/evtradinpost/) to see if there was anything in my area but there never was.

Then just before halloween there it was, a 1980 Comuta-Car only 30 miles away. I didn't even know what a Comuta-Car was when I first saw the ad, but I contacted the guy anyway. It took me two months to coordinate with him and by the time I was able to meet with the guy, I knew more about the cars than he did. :rolleyes: He brought the car up with him from Arizona so it has been around, but there are less than 3000 miles on the odometer.

[MetroMPG]

Good story. I've only seen one C-Car in person: there used to be one parked in someone's driveway in Ottawa when I was going to school there. I walked by it regularly. I'd like to know what happened to it - nobody in the Ottawa EV association knew anything about it.

Hope you'll keep us updated with your progress.

[MetroMPG]

This afternoon I picked up 8 used 6v batteries

[Len Case]

Remember not to fill them completely until after charging as the water/acid solution will expand when charging. Just put in enough to cover the plates, then charge them up.

[MetroMPG]

Thanks - I seemed to recall reading something to that effect, so that's what we did/are doing.

[MetroMPG]

he bought a battery

[MetroMPG]

Forgot to post this diagram

[MetroMPG]

Tried the battery tester this evening.

[Silveredwings]

Somewhere I read that it's common for metro EV conversions to end up with the batts in back and be too heavy in the rear (and who wants that? :D ). I'm not sure if that's true. It'd be good if you could balance it, but it'd also be pretty good if none of the batts were in the passenger compartment.

[Silveredwings]

...we want to try to retain stock appearance, even if we can't actually carry 4 adults :)
But I thought the inability to carry 4 adults was a stock feature. :D

j/k - I have no idea

[MetroMPG]

You've got a point. And in this day and age, you'd be hard pressed to get 4 adults in that Metro without exceeding its 695lb weight rating! Never mind any luggage. (I wonder if the GVWR changed when they switched to the Blackfly's body style - I've never looked.)

---

So this evening I made up 4 cardboard boxes - "battery mockups". Easier to monkey around with these under the hood to figure out placement and rack options than with the real things. I've seen a few people do this.

[Len Case]

Forgot to post this diagram after the back-and-forth last week.

It looks like the hours meter will run constantly with the precharge resistor across the pot contactor--perhaps you should change the negative connection to be on the other side of the key switch contactor?

[Silveredwings]

It looks like the hours meter will run constantly with the precharge resistor across the pot contactor--perhaps you should change the negative connection to be on the other side of the key switch contactor?
Good eye. I'm not sure but I think I may have introduced that change when I offered the "fuse re-drawing with a single ground."

Maybe it should be:
http://www.gassavers.org/attachment.php?attachmentid=163&stc=1&d=1169153129

[MetroMPG]

Yes, good eye! Gotta love peer review.

I'll update and post drawing version 2.1.

(SilveredWings - we're having version conflicts with the drawings. :D)

[MetroMPG]

http://forkenswift.com/offsite/schematic-forkenswift-2.1.gif

[Silveredwings]

Yes, good eye! Gotta love peer review.
...and open source. :)

I'll update and post drawing version 2.1.

(SilveredWings - we're having version conflicts with the drawings. :D)
quick, better get a source control system. ;)

[Silveredwings]

Ah memories of cannibalizing old TV sets. If you go with a used one, make sure you get a linear taper and not an audio (logarithmic) taper pot.

OK, if I understand the potentiometer conundrum, the Curtis uses a 0 - 5K ohm variable resistor (the center and one end of a pot.), and the forklift controller came with a ~23K ohm pot. From your photos, it looks like a common part:
http://rsk.imageg.net/graphics/product_images/pRS1C-2265106w345.jpg (http://www.radioshack.com/product/index.jsp?productId=2102789&cp=&sr=1&origkw=potentiometer&kw=potentiometer)

a single-turn, linear-taper, 1/4" shaft carbon potentiometer rated at 1 Watt (without a built-in switch I assume). Don't put an underrated part in or you might smoke pot ;).

Anyway, if you can't get the exact length shaft, you can always go over-size and cut it to fit (usu. aluminum).

So, which controller are you going to be using?

[MetroMPG]

The forklift pot is interesting. With a jumper wire (short) connected between the 2 ends of the resistor, the 0-23k pot acts as a 0-6-0 k pot - meaning resistance is highest with the wiper centered between the 2 ends and drops as you turn it either way from center.

[MetroMPG]

Tidbit: the 2 Youtube videos of the motor spin-up have been collectively viewed over 2000 times. Apparently there's a healthy interest in conversion info.

And Project ForkenSwift is inspiring other people. Check this out:

I’m taking inspiration from http://www.forkenswift.com/ as a low-budget conversion. That’s a good model to start on for us as we will be learning much along the way – so mistakes won’t be so costly!

http://www.43things.com/people/progress/Rorschaq/6037794

[MetroMPG]

PS - get the fuel pump installed?

[Silveredwings]

...working on it, thanks.

Edit: no really, I am.

[Silveredwings]

Tidbit: the 2 Youtube videos of the motor spin-up have been collectively viewed over 2000 times. Apparently there's a healthy interest in conversion info.

And Project ForkenSwift is inspiring other people. Check this out:

http://www.43things.com/people/progress/Rorschaq/6037794
Kudos for the Kudos. :D It's a really great project!

[Silveredwings]

PS - get the fuel pump installed?
It's in and tested! If I hadn't spilled a little gas it would have been perfect. :rolleyes: (news flash: I'm not perfect :eek: )

[MetroMPG]

Nice! Tested as in engine running, or good pressure?

[Silveredwings]

Nice! Tested as in engine running, or good pressure?
Good pressure, from the tank to all 3 carb bowl needle valves (new Healeys didn't always do as well ;) ).

I have a whole checklist before I feel it's safe to attempt an engine start.

Edit: actually I'm down to priming the oil pump and rotating the engine a few turns. Then I'm about ready.

Speaking of pressurization, I'll be replacing a lot of the cooling system (hoses, pump, thermostat, belt), but the that won't hold up the start.

[MetroMPG]

So... engine start yet??

---

The guy who initially explained to me how to use a 3-wire pot on the Curtis controller tells me my hack to make the forklift potbox work ... will probably eventually wreck the controller. Sigh.

So, probably got to bite the bullet and order that $29 unit to see if it'll work I guess. No point in tempting fate. DC controllers fail "on", after all.

[DaX]

DC controllers fail "on", after all.

Haha, YIKES! :eek:

[Silveredwings]

So... engine start yet??
I'm concerned about how well 20W50 oil gets through the engine and bearings at 8 degrees F (-13 C). :( I also forgot what kind of oil I need to put in the carb dashpots. I probably should use a multiviscosity oil since that engine compartment traditionally gets very hot.

I also got my speedo, temp and oil gauges back from the rebuilder. :)

[Silveredwings]

The guy who initially explained to me how to use a 3-wire pot on the Curtis controller tells me my hack to make the forklift potbox work ... will probably eventually wreck the controller. Sigh.

So, probably got to bite the bullet and order that $29 unit to see if it'll work I guess. No point in tempting fate. DC controllers fail "on", after all.
I'm still a little fuzzy about how that pot is wired. Is it off at 0 ohms and full on at 5K ohms (70 degrees)? Why did he think that "6K pot" would cause damage?

[MetroMPG]

It's not the 5 vs 6k ohms that's the problem, it's that I shorted 2 tabs on the controller together so I could use the forklift pot in its *2-wire* configuration rather than in the *3-wire* config that the controller is expecting.

It's one of these things that would take me an hour to properly describe in writing and in a diagram vs a minute to show you in person. Frustrating!

I'm just going to order the expensive potentiometer rather than trying to mod this one to make it work.

[JanGeo]

There is a spec on the three wire connection for the amount of current flowing through the pot from high to low and there probably is a certain amount of loading and current from the wiper into the circuitry that requires a certain amount of impedance in the pot to perform properly. If the resistance is lower the throttle responce is probably more exact and if the impedance is higher the effect may be a more tapered movement. In any event the only thing that could damage a controller is too much loading on the pot leads - if you have low voltage there then it should not really matter but if you have battery voltage then it is a concern. It may also be setup for forward and reverse with the full movement - depends if 0 ohms is off or not. The eCycle controller can be setup so that center position is 0 rpm and it goes forward and reverse depending upon which way you turn the pot from center. They spec a 5k pot but a 10k pot also works ok.

Best to measure what is coming out of the controller for voltage to the pot and go from there.

You should add CAPS to the controller input of sufficent value to handle the switching noise that the PWM will cause or else you produce a lot of EMF that could be harmful to your health and can induce currents in conductive materials near any of the battery cables. Just be careful of contactor currents charging the caps upon powering up - they should be limited via a charging resistor.

[JanGeo]

I'm concerned about how well 20W50 oil gets through the engine and bearings at 8 degrees F (-13 C). :( I also forgot what kind of oil I need to put in the carb dashpots. I probably should use a multiviscosity oil since that engine compartment traditionally gets very hot.

Dashpot oil usually was light weight hydralic fluid or brake fluid - I think I used marvel mystery oil or motorcycle fork oil. The heavier the weight of oil the more accelerator "pump" action you get - a richer mixture when pressing the pedal down. Too light an oil and stomping on the gas pedal will cause a lean "bog" stumble. It also dampens intake pulses at low RPM.

With 20w50 and a tight engine keep the RPM low until the oil warms up or else you will have a lot of oil pressure and put a load on the drive train turning the oil pump - timing belt or chain if not crank driven.

[Silveredwings]

Thanks for the info JanGeo, and that does make sense.

[Silveredwings]

Metro, sorry to sidebar your thread but my goal really is to sell the Healey to fund (and free up my garage for) an EV project. Such are my good intentions anyway... :D

[MetroMPG]

Best to measure what is coming out of the controller for voltage to the pot and go from there.

Unfortunately, I don't have enough knowledge /

[MetroMPG]

Metro, sorry to sidebar your thread but my goal really is to sell the Healey to fund (and free up my garage for) an EV project. Such are my good intentions anyway... :D

Don't worry about it! It's interesting. And perfectly related as sidebar material with the "EV funding" angle.

[JanGeo]

Connect the pot to the controller and turn it on - in the 0 rpm position and read the voltage across the wires on the pot. Something comes to mind that there was a safety feature on the controller that would shut it down if there was no pot connected in case the wires broke or something. Anyway there should be plenty of info on the controller on the web about the inner workings and how the pot connects to the internal circuits. You do want to use a good pot that will not wear out under constant use. Yes I saw the resistor across the power relay - that should do the trick.

[MetroMPG]

Minor update: just pursuing a few leads on potentiometers that will both work inside the potbox, and talk to the Curtis.

Taking my time. The fact that it's -20 out has removed a lot of the urgency for getting back into the garage.

[Silveredwings]

Oh man, you sure do get the lake effect, don't you. I do hope you are talking about degrees C, not F. It was a balmy -17 C at my house this morning in still air, but now it's ~-21 C with the wind chill.

[SVOboy]

When I walked to class this morning it was a cool -24C and now it's up to -17C, dunno with the wind chill though, :)

[MetroMPG]

Yep, that was in C. Just walked downtown. Got a ride back. Temperatures like this sure make you appreciate the 25% efficiency of the ICE. Gimme some wasted heat - NOW!

[MetroMPG]

Well crud. Just missed out on an eBay auction for a potbox that had all the right specs.

Got another price for a Curtis replacement pot: $45 CDN. That, to me, is just insane, considering you can go into radio shack and get a 5K pot for $2. But the standard seems to be 300 degrees of rotation, not 50.

It's looking like buying the replacement will be the route to take.

I just hate spending 5% of our total budget on a wee potentiometer :)

[The Toecutter]

Gimme some wasted heat - NOW!

What's good about EVs is that you can install ceramic heaters. No need to wait for any ICE to warm up. you can get your heat as soon as you want it.

[Silveredwings]

Well crud. Just missed out on an eBay auction for a potbox that had all the right specs.

Got another price for a Curtis replacement pot: $45 CDN. That, to me, is just insane, considering you can go into radio shack and get a 5K pot for $2. But the standard seems to be 300 degrees of rotation, not 50.

It's looking like buying the replacement will be the route to take.

I just hate spending 5% of our total budget on a wee potentiometer :)
Correct me if I'm wrong, but aren't you using only 2 connections to the pot (one end and the wiper)?

So what if you took a pot with 300 degrees of rotation moved it only 1/6 of the way to 50 degrees and stopped? In that case wouldn't a 30K pot work?

The next trick is finding one of those ;) .
http://www.elexp.com/srp_s30k.htm

I know you can get a 50K pot at radio shack. 0 to 50 degrees would be 8.3K. Is that bad? Worth testing? Or wait for that $0.90 30K one :D

[MetroMPG]

No need to wait for any ICE to warm up. you can get your heat as soon as you want it.

Yes, instant is nice.

Some ICE cars have instant heat too. I don't know about the US market cars, but the last generation Echo hatch that I test drove had a honking big resistor in the heating duct that you could light up as soon as you started the car. It didn't feel "hot", but warm air did come out of the vents within a few seconds.

But man, the BTUs coming out of an ICE heater once warm is pretty hard to beat with ceramic heaters.

Even the EV1 had a lousy heater, from first hand reports I've read. (Though it was a heat pump, not a ceramic resistor.) Efficiency, efficiency...

[MetroMPG]

Correct me if I'm wrong, but aren't you using only 2 connections to the pot (one end and the wiper)?

Nope, I need all 3 wires for the Curtis. (Otherwise the existing pot in the potbox would work.)

The amount of time I've spent looking for a deal on the right pot, I could have just done some work and earned enough $ to buy several at list price. :D

But it's the principle!

(I even considered making my own wire-wound pot, but couldn't find any decent resistive wire around the workshop ;) )

[MetroMPG]

I even took apart the Playstation analog controller to see what pots it has.

[Silveredwings]

I even took apart the Playstation analog controller to see what pots it has.
I don't think that's weird at all. One time my brother was in need of some kind of high wattage variable resistance for an impromptu project and used a piece of ham he had lying around. :eek: He had wires stuck in at different points. :rolleyes:

Kids, don't try this at home. :D

[The Toecutter]

Kids, don't try this at home.

You're telling this to someone who picks up brown recluse spiders and used to break lightbulbs and stick the tungsten filaments in electrical sockets as a kid.

[MetroMPG]

Hmm: http://www.fsipcatalog.com/p-4053-model-810-potentiometer.aspx

0-5k ohm, says an email from the vendor. Diagram shows 3-wires. It's a slide pot, but that doesn't really matter. Looks like it may also have microswitches built in.

$14 plus shipping.

http://www.fsipcatalog.com/images/Product/medium/MODEL810.jpg

[Silveredwings]

I was thinking that slide pots are notorious for getting dirty and flaking out, but after looking at it, I think that one may be pretty well sealed. :thumbup:

[MetroMPG]

Well, I got some advice & encouragement from an experienced EVer...

[Silveredwings]

Nice work Darin. :cool:

[MetroMPG]

More pics:

[Silveredwings]

Very, very nice. I am properly impressed. You do make it look easy. :thumbup: :)

[MetroMPG]

(Is it news to say "no news"?)

Nothing to report this week/end. Didn't get a welder. The weather has put a serious crimp in my desire to do a quickie road test. And I have a cold.

Spent a little time looking for angle iron for battery trays. A free bed frame would be nice (though I know some EVers say "proper", thicker angle iron is preferred). Had a couple of leads through the local freecycle (http://freecycle.org/) group, but nothing just yet.

[rh77]

Nice job :thumbup: it looks like it's coming together! Any thoughts of mounting some batts in the rear for weight distrib?

RH77

[MetroMPG]

Yeah, definitely. Remember the batts we have are 6v, so those 4 in the front represent only 24v of our 48v goal. So we'll be putting 4 in the hatchback, or under the rear seat if there's enough room - we're thinking of making a batt box that extends down into the space that the gas tank will be vacating. Probably not enough room though.

[skewbe]

.. A free bed frame would be nice (though I know some EVers say "proper", thicker angle iron is preferred)...

Bed frame sounds perfect to me, good reuse of materials and plenty strong.

[Silveredwings]

Bed frame sounds perfect to me, good reuse of materials and plenty strong.
I did that once and learned afterwards to make sure the angle iron isn't plated with zinc or something before starting to weld; it can produce poisonous gases.

[MetroMPG]

Yes! I actually learned about that this summer when researching building my bicycle trailer (http://www.gassavers.org/showthread.php?t=2170) (from zinc coated electrical conduit).

Breathing the fumes can give you "metal fever".

It's better done outdoors, with a good breeze. (Or not at all.)

[nathan]

where abouts in easter ontario are you? ive got an old bed frame laying around. if you're not too far away i wouldnt mind seeing the forkenswift in exchange for the frames. i could bring my mig welder along too if need be.

[MetroMPG]

PM'd you, Nathan.

[MetroMPG]

Hadn't talked to Ivan for about a week or thereabouts.

Turns out while I was tracking down a bed frame (got one this week) he was too. (Actually he got some thicker angle iron).

Word is he's already cut the pieces for the front batt trays and he's going to try to have a friend weld them together tomorrow.

Ah well, we'll likely still be able to use the bed frame metal for the rear tray.

[MetroMPG]

Supposed to be working on the batt trays

[MetroMPG]

Front battery trays

[MetroMPG]

Picked up 2 more batteries from

[MetroMPG]

Still no welder to finish the battery trays.

[MetroMPG]

This evening: wired the 36v string togeth

[MetroMPG]

This evening: wired the

[SVOboy]

When's the first go at?

[Silveredwings]

I can hear those dueling banjos already... :D

[MetroMPG]

Squeeeeal like a Curtis! (If you get that, well. Yep.)

The go attempt will be this weekend, if not before. (What month is this? It's September, still, right? Are we on schedule?)

We could try in the evening this week, but I want to document the milestone, so it needs to be light out.

[MetroMPG]

PS - SW - how's the Healey?

[SVOboy]

Have you ever geared up the FS website?

[Silveredwings]

PS - SW - how's the Healey?
Yup, I get it. Speaking of banjos, I'm trying to make one (as in banjo-bolt fitting). I think I finally figured out how to get oil pressure before turning the engine.
The only trouble is the thread is 3/8" X 28 (ever heard of it?) So I'm tinkerin'

[MetroMPG]

http://www.forkenswift.com exists, but it mostly points to other places (like this thread). I don't think I'll work on fleshing that out until the car is further along. Let's say after the pack is properly installed on racks & cabled, and the controls are complete and mounted. And that would be some time in... September?

SW: You got me - never heard of it. Glad I'm not the only one tardy with the garage projects though!

[The Toecutter]

Squeeeeal like a Curtis! (If you get that, well. Yep.)

I believe only the 1231C models made that squeal.

[MetroMPG]

Unfortunately for Curtis, the model that squeals appears to have become a "brand identity" thing among hobbyists. (The golf cart controller we have is actually a Cursit, and it's quiet as a mouse. About as powerful too.)

[Coyote X]

how about posting a build log on that site similar to something like i did on my mantaproject.com site? It is easy to do, every day you work on the car take some pics of your progress and dump them in a dir on the webserver and update the index.html to point to the new page and later on when you get time you can add text and a description of the pictures.

Works pretty good for me that way since I get lazy sometimes doing my updates and I can just dump the pictures into the dirs and fix up the html as I get around to it. The program that makes the image map thumbnails I use on that site is also free and takes like 5 seconds to use generating the basic html page for you that you can edit later as you feel like it.

[MetroMPG]

Well, this thread is my build log :)

I see what you mean though. Cool site - I love the factoid about "Shaky Jake". Classic.

The plan is to eventually copy bits of this thread to make the "conversion diary" part of forkenswift.com and point back here if people want to talk about it/comment.

(Matt, you are backing up the server right?)

[MetroMPG]

Just noticed the two YouTube vids of the motor power-ups have been viewed over 5000 times. 5314 to be exact. Amazing.

[MetroMPG]

Remember a while back I said the used floodies

[MetroMPG]

Forgot this one:

[rh77]

I just wanted to say that not only is the documentation of this project very well done, but to have the project come together close to the anticipated budget is awesome. :thumbup:

Keep us posted...I know I'm excited to see new results as they're posted :D

RH77

[MetroMPG]

Thanks, Rick.

[Silveredwings]

$500?!?! Well...boy howdy Billybob, that's amazin'

[MetroMPG]

Did anyone see the epic PBS documentary (http://www.pbs.org/wgbh/nova/transcripts/2303b29.html) about the salvage/restoration of the B-29 bomber "Keebird" in Greenland? And what happened on the (post resto) maiden flight?

http://www.ramonacafe.com/Keebird/Kee16.jpg
source: http://www.ramonacafe.com/keebird.htm

[Bill in Houston]

Did anyone see the epic about the salvage/restoration of the B-29 bomber "Keebird" in Greenland? And what happened on the (post resto) maiden flight?
Yeah... What are you saying? One of your mechanics worked so hard he died, and then your car burned to the ground when you powered everything up? That was pretty depressing.

[MetroMPG]

I was floored by the program. Very interesting and pretty intense too.

Nope, nobody has died yet on Project ForkenSwift. I will be keeping a fire extinguisher handy though!

[MetroMPG]

he 36v string was resting at 38v

[MetroMPG]

If 6v floodies play by the same rules, then 37.8-38.1 is full.

Brock, you reading this thread? You use 6v floodies in your solar system, don't you?

[Bill in Houston]

I was floored by the program. Very interesting and pretty intense too.

Nope, nobody has died yet on Project ForkenSwift. I will be keeping a fire extinguisher handy though!
DEFINITELY want to keep a fire extinguisher around. Good thinking.

Yesterday I went all the way back and read this thread from the start. Your story of welding on the inside and then leaning out to blow out the fire on the outside made me cringe!

[MetroMPG]

It made me winded. ;)

After the first incident I had a hose on standby, in case I ran out of breath putting out the flare-ups.

It did give me an appreciation for what can happen with brazing, welding (or arcing battery connections for that matter).

[Silveredwings]

It made me winded. ;)

After the first incident I had a hose on standby, in case I ran out of breath putting out the flare-ups.

It did give me an appreciation for what can happen with brazing, welding (or arcing battery connections for that matter).

Atleast if anything metal breaks on the car, you know you can weld it with the batteries (keep some coat hangers around). :D

[Silveredwings]

WOW, that's really, really great news. Kudos on the milestone and the impromptu accolades.

I wonder if there is a worthwhile way to "recondition" them. I've read of some rejuvenating methods, and personally tried one procedure in my more desperate past (the zapping method - and succeeded), though it wasn't for a deep-cycle project. Better luck on the batteries, but remind me, how much range were you hoping for?

[Peakster]

I got it all on video :D Will post some tomorrow or Sunday.

Awesome news MetroMPG! I can't wait to see the video. Does this mean that ForkenSwift will be your new daily driver? :)

[Bill in Houston]

Was that Volt video some kind of joke? I have no idea how to make an electric car that noisy. Or slow. A golf cart is more inspiring than that thing. I did only watch the first couple of minutes.

[zpiloto]

Was that Volt video some kind of joke? I have no idea how to make an electric car that noisy. Or slow. A golf cart is more inspiring than that thing. I did only watch the first couple of minutes.

Yea I was thinking, that's a great car for driving around a parking lot at less than 10 mph. Sounded like someone with a leaf blower was next to the guy filming:eek:

[omgwtfbyobbq]

Yea I was thinking, that's a great car for driving around a parking lot at less than 10 mph. Sounded like someone with a leaf blower was next to the guy filming:eek:

That, is the sound of hundreds (or a couple given the speed) of Hamsters screaming.

[Brock]

I need to check on this thread more often ;)

I used to have twelve 6v flooded in my system. They are 7.1-7.2v when full per 6v. So if you had 6 in series full should be 42.6 to 43.2 and should stay at that voltage with about 6 amp charge. If you need more then about 6 amps they aren't full yet. What voltage are they at when the charger is running?

And yes after resting from a full charge should be 6.3 per battery or 37.8 for the string.

I am running eight 8A8D's AGM's now, just about 2000 amps at 12vdc or 24kw. I really like AGM's, but they don’t' come cheap.

[Silveredwings]

Yup, I get it. Speaking of banjos, I'm trying to make one (as in banjo-bolt fitting). I think I finally figured out how to get oil pressure before turning the engine.
The only trouble is the thread is 3/8" X 28 (ever heard of it?) So I'm tinkerin'
Since you asked... :)
I bored out the threads on a soft steel nut, put a hole in the side of it, made a hose-barb out of some brass tubing, and soldered it all together to make the banjo for my homemade banjo-bolt fitting.

Parts: a nut, some tubing, and the highly unique "banjo bolt"
http://www.gassavers.org/attachment.php?attachmentid=319&stc=1&d=1175475262

My resulting "banjo" (front)
http://www.gassavers.org/attachment.php?attachmentid=320&stc=1&d=1175475262
(back)
http://www.gassavers.org/attachment.php?attachmentid=321&stc=1&d=1175475262

Next, I'll use it to bypass the oil pump and force oil into the engine the hard way. ;)

[rh77]

What a milestone!

You should enter it in parades or something -- and spread the word :thumbup:

Definitely custom paint and graphics (but yeah, I know it's not your style) -- but I think average people will eat that stuff up as the Neon guys did.

Any plans?

RH77

[MetroMPG]

I wonder if there is a worthwhile way to "recondition" them. I've read of some rejuvenating methods

I haven't looked into this yet, though I have seen the word "desulfator" floating around various places.

I had an idea for upping the supply of used batts which may work out. I've charged the car a few times now and started monitoring individual battery charges - some of them are quite healthy. Others are toast - and of course the pack is only as good as its worst batt, so there may be hope.

Does this mean that ForkenSwift will be your new daily driver? :)

Nah, my old 10-speed will remain the daily driver!

And yes after resting from a full charge should be 6.3 per battery or 37.8 for the string.

Thanks for that info. I may pick your brain with more questions...

I am seeing 6 amps when full. I'll have to double-check the charging voltage, but I think it's around 45.

Any plans?

Nothing yet. "Custom paint" will entail sanding the rust spots off and coating with colour match! Actually, I seriously want to put a racing stripe on it. ;) Irony defined.

[MetroMPG]

Parts: a nut, some tubing, and the highly unique "banjo bolt"

Hey, nice work! Very nice indeed.

[MetroMPG]

BTW, I made and uploaded a neat 5-minute video of the first drive activities. Just waiting for YouTube to process it and spit it back out.

Today: added 2 more batts to the string, for a total of 48v. This made a noticeable difference; it turned the car from "interesting science experiment" but too slow to be practical, into a barely usable car. At 48v, it would never handle the cut & thrust of typical urban traffic, but as an NEV equivalent on the side streets of a small, quiet city, it'll be fine.

With some effort (EV hypermiling!) I managed to go 5.x km around the neighbourhood today on one charge (but 3 separate journeys).

I also started documenting individual battery voltages after each run to see if I can figure out which batteries are weakest. Turns out driving around the neighbourhood is an excellent "load test" procedure - the bad batteries are quick to reveal their true selves, relative to their pack-mates.

[MetroMPG]

http://www.youtube.com/img/pic_youtubelogo_123x63.gif

http://sjl-static16.sjl.youtube.com/vi/bDERyAILOak/1.jpghttp://sjl-static16.sjl.youtube.com/vi/bDERyAILOak/2.jpghttp://sjl-static16.sjl.youtube.com/vi/bDERyAILOak/3.jpg (http://www.youtube.com/watch?v=bDERyAILOak)

http://www.youtube.com/watch?v=bDERyAILOak

[DaX]

Great video Darin!

[zpiloto]

Man that is so cool!! What kind of shape are the batteries in after the test drives? Nice rolling stop by the way:o

[Bill in Houston]

I had an idea for upping the supply of used batts which may work out. I've charged the car a few times now and started monitoring individual battery charges - some of them are quite healthy. Others are toast - and of course the pack is only as good as its worst batt, so there may be hope.
I was thinking that since you have a ready supply of used batteries, you could continue to collect them, charge them, load test them, and then keep the ones that do the very best. You will probably find a lot of really bad ones, but all you need is 8-10 really good ones, right?

Nice video. It really is amazingly quiet. You might need some sort of very soft horn or beeper to use in parking lots and near pedestrians so people don't step out in front of you. Something that plays the sound of George Jetson's spacecar would be perfect. :-)

Also, is there an concern about hydrogen buildup in the charging area? I don't know much about batteries.

[zpiloto]

Nice video. It really is amazingly quiet. You might need some sort of very soft horn or beeper to use in parking lots and near pedestrians so people don't step out in front of you. Something that plays the sound of George Jetson's spacecar would be perfect. :-)



This is a very good point. I have had this happen quite a few times in the Prius. Folks just assume that if it's not making noise it's not moving.

[Bill in Houston]

This is a very good point. I have had this happen quite a few times in the Prius. Folks just assume that if it's not making noise it's not moving.
Hybrids will end up with some sort of government mandated ICE-off noise generator before long. That will be a sad day.

[Silveredwings]

That's terrific! Thanks for showing us the current state of the tests you're conducting. I was shocked to see that the Neon guys got a charge out of it too. :thumbup:

by Bill in Houston: Nice video. It really is amazingly quiet. You might need some sort of very soft horn or beeper to use in parking lots and near pedestrians so people don't step out in front of you. Something that plays the sound of George Jetson's spacecar would be perfect. :-)
That's what I was thinking. :D

[rh77]

I was shocked to see that the Neon guys got a charge out of it too. :thumbup:

Are "Shocked" and "Charged" Freudian Slips? ;)

BTW, I concur wholeheartedly: the Jetson's car sound would be ideal :thumbup:

[Silveredwings]

Are "Shocked" and "Charged" Freudian Slips? ;)

BTW, I concur wholeheartedly: the Jetson's car sound would be ideal :thumbup:

No but current and conducting were. ;) j/k

[MetroMPG]

Man that is so cool!! What kind of shape are the batteries in after the test drives? Nice rolling stop by the way:o

They're not good. Amazing what you can learn with a DMM: the pack is very unbalanced (batts resting at very different states of charge after use & charging), and I've already found several that suffer from serious voltage "sag" relative to the others, when measured immediately after loading them up (driving). And I've also found a few batteries that appear reasonably healthy.

That didn't even qualify as a "rolling stop" :)

I was thinking that since you have a ready supply of used batteries, you could continue to collect them, charge them, load test them, and then keep the ones that do the very best.

That's probably what we'll do, for now. I'm going to ask the forklift company guy who's been supplying me with batts if he'll connect me with his supplier. There's apparently a guy who drives around delivering new & picking up used batts. I want to meet this guy ;)

Also, is there an concern about hydrogen buildup in the charging area? I don't know much about batteries.Yes. The closer a flooded battery approaches full charge, the more it will "gas", releasing H2 and O2. Many conversions with batteries enclosed in the trunk or in battery boxes in the passenger compartment (ie hatchbacks), run brushless fans to circulate outside air through the boxes.

That's terrific! Thanks for showing us the current state of the tests you're conducting. I was shocked to see that the Neon guys got a charge out of it too. :thumbup:

You're welcome. I was quite amped about the whole thing myself!

[Peakster]

What gear were you in when you reached your top speed? I would think that electric motors would love revving at high RPM in a lower gear than doing a lower RPM in a higher gear.

On another note, maybe some electric-motor braking (instead of coasting in neutral) would act like regenerative braking on hybrids? I'm sure driving an electric car is a totally different ballgame than an ICE powered one.

[MetroMPG]

You're right - it is a totally different

[Snax]

You and the Prius guys might have to rig up a playing card in the wheel spokes like us kids did to our bikes.
No. Just attach two short chains to the undercarriage so that the free end of each drags upon the ground. They'll serve double duty as an audible warning and as 'electrical pickups' (or so one might say), as they spark along the ground. ;)

[MetroMPG]

You and the Prius guys might have to rig up a playing card in the wheel spokes like us kids did to our bikes.

You're closest to what I'd actually like to do: I want to use a bicycle bell. Maybe hooked to a solenoid to sound it.

I'm actually already fairly concientious towards pedestrians since 40-50% of the time the Blackfly is moving, its engine is off. I often tap the horn to let people know I'm there.

[Silveredwings]

You're closest to what I'd actually like to do: I want to use a bicycle bell. Maybe hooked to a solenoid to sound it.

I'm actually already fairly concientious towards pedestrians since 40-50% of the time the Blackfly is moving, its engine is off. I often tap the horn to let people know I'm there.

How about half a door bell? :)

[OdieTurbo]

Awesome stuff! Just had a chance to read the whole thread and watch the video! I am duly impressed! Now if I could just do this to say a '65 Spitfire...

[MetroMPG]

SW: good idea! But which half? The "ding" or the "dong"?

Oldie: re the Spitfire - watch for Toecutter's thread. That's his plan.

[Silveredwings]

SW: good idea! But which half? The "ding" or the "dong"?
I'm not even going there... ;)

Oldie: re the Spitfire - watch for Toecutter's thread. That's his plan.
I thought he was a making a GT6-EV, though I'd prob go for the spitfire, in fact I recently saw an EV kit for one.

[MetroMPG]

You're right. GT6. Excuse my ignorance, but are they not the same chassis, one hard top, one convertible?

[Silveredwings]

You're right. GT6. Excuse my ignorance, but are they not the same chassis, one hard top, one convertible?
...and a 6 vs. a 4 cyl.

[rh77]

I just had a chance to watch the vid (sorry a bit late -- couldn't do it at work :o )

I love unsolicited reaction by the guys on the street when it's explained as electric.

Bystander: "Bull****. Really? Awesome!"

Meanwhile back at the repair car, $20 is exchanged for an "I told you so" between buddies. :D

BTW, do you cut your own vids? Good background music.

So regarding the battery pack inequalities, what can be done (cheaply and easily) to prevent this problem?

Do you need all batts to run? ...or can you run on x-number until discharged, switch to the next set, etc (or would that discharge them too quickly?) Or you could alternate among them -- guess this would let some "rest" while others were in use, but put a lot more strain on the cables. ...would probably require a series of heavy-duty solenoids or relays.

Do you (or have plans to install) a Voltage readout inside?

OK, I'm done with my 20-questions :)

Keep up the great stuff.

-Rick

[Silveredwings]

OK, so what Metro parts are leftover to sell?

[MetroMPG]

OK, so what Metro parts are leftover to sell?

Not enough to pay for replacing the batteries we're sure to murder as we figure all of this out!

[lemmiwinks]

Been following this for a while now and thought I'd chime in. Firstly, congratulations on what is shaping up to be a fantastic conversion, and on an affordable budget too! Now about those dodgey flooded batteries. I suggest you buy a hydrometer (couple of bucks), battery load tester ($50) and build yourself a desulphator or two (about $20 worth of parts each).

I just finished my second one, which is also my first ever attempt at etching a PCB. I've been testing on a 220CCA 12V flooded battery. Over the course of a week or so the specific gravity of the electrolyte in the cells has shown improvement (moving from "Fair" into "Good") which is enough to make me think this thing actually works.

A desulphator is by no means a magic bullet, it can't recover all batteries, and the one I built is quite slow - we're talking progress measured in weeks or months, not hours and days. But, you don't seem to be in too much of a rush, you've got a great supply of cheap/free batteries at your disposal so I'd say it's worth a shot.

The plans for the desulphator I built are here: http://www.shaka.com/~kalepa/lowpower.htm

Here's an article by the inventor describing how it works:
http://homepower.com/files/desulfator.pdf

There is a low activity forum as well. I didn't post there, but by reading through the messages you can learn a lot:
http://p198.ezboard.com/Lead-Acid-Battery-Desulfation/bleadacidbatterydesulfation

The Alastair Couper plans @ http://www.shaka.com/~kalepa/lowpower.htm are for 12V batteries, for 6V, simply double R2 to 44k. I strongly suggest anyone contemplating building one reads this: http://www.shaka.com/~kalepa/faq.htm There are kits available too if you just want to solder one up.

If you're considering a commercial solution, the only one I've heard of that is reported to actually do anything is from: http://www.batterylifesaver.com. I can't speak for or against it, but I can say I bought one of these http://www.batterylifeplus.com/pulse.html and it didn't do anything, while the one I built myself for much less has produced measureable results. I'm cautiously optomistic.

Anyway, good luck and I look forward to more updates!

Cheers,
Ash

[Silveredwings]

Nice exposé by Jerry at evconvert.com (http://www.evconvert.com/article/forkenboogie)

[MetroMPG]

Ash: thanks very much for chiming in with that info & those links. I had a quick look through. Will delve in further, later. I did buy a hydrometer, but haven't tried it yet (been relying on the DMM alone to this point).

SW: Jerry's funny. For all the "Forkenlookers" out there...

[lemmiwinks]

No worries. I found it pretty heavy going (I'm an electronics dunce) but over the course of about a month I've progressed to the point where I'm able to make working versions with their own PCB's. If I can pick it up, anyone can :D A DMM is good for showing you the OCV of the batteries, and if you can juggle it, the voltage under load, but a hydrometer will give you a better indication of the actual condition of a flooded battery.

A brief note about electric motors (I apologise in advance if you already know this), their torque curve is very different to an ICE. As motor rpm approaches peak, torque approaches 0. So, the faster they rev, the less torque they have, though obviously there's a sweet spot between rpm and torque. While we're talking torque, current is roughly proportional to torque, and voltage is roughly proportional to rpm. So more amps = more torque and more volts = more rpm. The tradeoff is that too much current = excess heat and too many volts (above the rating in a brushed motor) = accelerated brush wear and arcing on the commutator. In extreme cases overspeed will cause the rotor to come apart which is why you must never run a series wound motor at it's rated voltage with no load. Again, there's always a sweet spot.

I generally treat the ratings as a rough guide :D If you go too far over them, some forced air cooling via a fan to cool the windings is a good idea. Electric motors are rated at their continuous power output anyway, peak output is normally at least twice the continuous. I guess what I'm trying to say is find out how much current your controller is rated to deliver, use some Ohms Law[1] to figure out how many Watts you're delivering to the motor. Voltage sag under load will effect things significantly, but it give you a starting point to play around with anyway.

You might want to consider an ammeter and shunt (I got mine from
http://www.evparts.com but maybe you can get one from another forklift or something). You could use a friend holding a DMM plus the ammeter readings to get an idea of voltage sag under load, and also how much current your batteries can actually deliver to the controller.

Gerrys evconvert.com site is what brought project forkenswift to my attention. I've been hooked ever since :) I'd love to do a car, but not gonna happen in the foreseeable future (getting a modified car registered here is nothing that bulk $$ can't fix :mad: )

BTW, I just watched your video (forgot to yesterday). I loved it! There's nothing so sweet as the sound (or lack of it) of an EV cruising down the street. I especially loved the EV1 rip off at the end, classic :D

Cheers,
Ash


[1] i = v/r where i = current in amps, v = volts and r = resistance (watts)
http://en.wikipedia.org/wiki/Ohm's_law

You can shuffle things around like in any equation and I prefer to think of it this way: Watts = Volts * Amps. So if your "ESS" is 36V and it's delivering 100A to the motor; Watts = 36 * 100 = 3600W (incorrectly assuming no voltage sag under load).

[MetroMPG]

A DMM is good for showing you the OCV of the batteries, and if you can juggle it, the voltage under load, but a hydrometer will give you a better indication of the actual condition of a flooded battery.

Good tip, thanks. The book I've been reading "Build Your Own EV" (appropriate to crack it open, now that we're half finished, eh?) sort of pooh-poohs hydrometer use in favour of a DMM, which I took at face value. But I realize in retrospect, they're expecting you to be using a nice set of shiny new batteries.

A brief note about electric motors (I apologise in advance if you already know this), No apology needed. Good refresher.

You might want to consider an ammeter and shunt (I got mine from
http://www.evparts.com Got one! eBay, NOS. 50 mv shunt with a 600A scale gauge.

You could use a friend holding a DMM plus the ammeter readings to get an idea of voltage sag under load, and also how much current your batteries can actually deliver to the controller.Yes - as much as it's useful (and fun!) to drive the car around and do DMM readings immediately afterwards, a proper load test is the way to go.

(getting a modified car registered here is nothing that bulk $$ can't fix :mad: )Yes, I've read that about both Australia and NZ. What's up with you folks down there? And all the trouble that the little REVA EV stirred up? Wow.

I especially loved the EV1 rip off at the end, classicCool - you're the first one who recognized it! :thumbup: (Or at least said so.)

[MetroMPG]

Toecutter: thanks for posting that reply to the speed/performance question in the comments under the Youtube video (http://www.youtube.com/watch?v=bDERyAILOak)

I tried 4 different times to reply to that person, but YouTube kept eating my response. It accepted it, said it was posted, but it never appeared on the page. Sometimes YouTube bites.

Also - good to see you get the point in about 130 mph. ;) Got to counter the myth / perception (that I'm contributing to) that EV's are slow and boring!

[MetroMPG]

Guess what I bought today :)

[SVOboy]

Weld me a dream?

Had you ever thought of using motorcycle batteries?

[MetroMPG]

Mcycle batteries? To power the car?

[SVOboy]

Yessir.

[MetroMPG]

Yessir.

No, hadn't really thought of that. Probably would be difficult because their terminals aren't beefy enough to take the amps we'd be asking from them. Packaging would be easier though...

[SVOboy]

How many amps would that be?