Ben Nelson's Electro-Metro Build thread

[Johnny Mullet]

I would locate a junkyard replacement trans for that car. I thought about rebuilding my trans, but scrapped that idea whn I was lucky enough to locate one for $250.00

The welding looks great!

[bennelson]

I have been thinking about battery configuration some more.

I have 12 batteries that are 12 volt each. Each weighs about 75 lbs.

I have a 400 amp, 48-72 volt PWM DC motor controller.

Therefore, I need to use either 6 batteries in series or six PAIRS of batteries in series for my battery pack.

I really can't do the math to figure what the car's range would be, because I don't know how many watt-hours per mile it uses yet.

The advantages to using 6 batts in series is the I shouldn't have to get too wild beefing up brakes and suspension, and the batteries should fit fine under the hood and in the cargo compartment. It also leaves me with a "spare" six batteries I could keep and use later.

Using all twelve batteries would give me much better range, but I would also need to beef-up suspension and brakes, and find a place to put them all. I think that would mean removing the back-seat, converting it to a 2-person car. I would then build a low box in the whole back of the car - something similar to a CRX or Insight, with room on top to use use for storage, carrying groceries, etc.

hey Darin, how many watt-hours per mile is the Forkenswift using right now?

Anyone's thoughts on battery configuration?

[bennelson]

Here is what that welding repair looks like cleaned up and painted.

I used a fiberglass brushing wheel on a cordless drill and Rustoleum, brush-on, oil-based gloss black paint.

[MetroMPG]

Originally Posted by bennelson

hey Darin, how many watt-hours per mile is the Forkenswift using right now?

Average has been 312 wh/mile, driving pretty conservatively (medium duty hyperwatting).

As for battery config, You can always start with 6 and add the buddy pairs later. It won't really change what your battery layout is up front (you'll only have room for 3 or 4), and you can always consolodate in the rear if you need to.

[MetroMPG]

Nice welding, Tim! Beats the "squeezed out bird poo" that mine resembles.

A hundred years from now, all that's going to be left of this car is that control arm mount.

[bennelson]

Yeah, I agree with you on being able to add batteries later.

Maybe I just do a real bare-bones approach to everything on this project just to get it on the road this summer and then tinker/rebuild/change everything next summer.

I just got an email from a fellow EV builder who helped partially take apart the transmission yesterday.

His subject line was "feeling adventurous?"
followed by this photograph and link


LINK

PS: I think the bearing causing the problem is the one in the upper right of the photograph

[bennelson]

Is it modern art?

Nope.

It's the field coil from the Electro-Metro forklift motor being hung up so I can use a spray-on non-conductive varnish on it.

The spray-on is a green epoxy designed for use with electric motor parts and other things you want to insulate.

Once it's dry. I can put the motor back together again. Hope it spins better and pulls a few less amps when this is done.

[bennelson]

Been thinking about chargers some more.

Made me remember that I already have a charger. A HUGE one that came with the forklift.

According to the specs on the charger's ID plate, it is:

Hobart model 1R18-450

AC input: 208/240/480 single phase, 60 hz.
Max amps 29/26/13

DC output
Volts: 36 Cont Amps:65 Max Amps 95

It looks like I only need to change some jumpers inside to convert it to 240 volts.

Another set of jumpers controls output amperage, but it only has a scale saying higher and lower, not a listing of what the actual amperage would be.

Looks like I need to talk to an electrician.

This thing sure has a big transformer inside it. There is also a weird looking part towards the back, which I think is a very large resistor. This thing must get hot when it's running.

Even if I can't use this charger, it would still be a great source for a 200 amp ammeter, some cabling, and fuses.

Here are a few photos of it.





Is the above a giant resistor?


Plugs. 30 amp twist lock and large Anderson.

See all the forklift charger photos, including spec plate, etc. at:
Charger Images

[MPaulHolmes]

Originally Posted by bennelson

Is the above a giant resistor?

Your mom's a giant resistor.

[bennelson]

A not-so-distant junkyard claims to have a car the same year, engine, and tranny as mine. Guy on the phone said they were going to sell it as a used car, but a piston blew right when he went to start it up.

They are asking $275 for the transmission.

A local tranny guy who does work on the side, said it would be $250-$500 labor to fix my tranny. There is another tranny guy I wanted to go talk to, but I haven't got a call back from him yet.

So far, it sounds like this junkyard transmission would be the easiest way to go. At $150 for a rebuild kit, doing it myself would be the cheapest, scariest way to do it.




Wait a minute, Geo Metro in ok condition, other than a dead engine? Could become Electro-Metro number 2!

Great, now I wonder how much they want for the whole thing...