Firefly Electric Conversion

[Stubby79]

Someone was asking what it weighed...



Scale says 980kg. Scale was already reading 20kg with nothing on it, and I probably had at least another 20kg of junk kicking around in it. So less that and converted over, that's 2068 lbs, meaning if I didn't have all those heavy little lead acids in the trunk, she would be pretty darn close to stock weight.

Something for me to consider in the future...

[Daox]

Awesome updates. Congrats on the maiden voyage too! Glad to see it on the road.

[Stubby79]

Thanks.

Made battery covers today:



Polycarbonate can be cold-bent in a brake:


However, it will spring back...had to fold it completely over - with a lot of force - to get it to stay at 90 degrees:


Trimmed and adjusted to fit with my dremel and a cutting disc:


Front one is tucked under the bumper:


...all to keep water, fingers and tools away from the battery terminals. (Now I can work under the hood without being paranoid)

[MetroMPG]

Learned something new today (cold bending polycarbonate)!

[Stubby79]

Originally Posted by MetroMPG

Learned something new today (cold bending polycarbonate)!

Me too. I figured there would be cold-bendable plastics, I just didn't expect it to be polycarbonate. I googled the how to yesterday, after the plastic vendor pointed it out.

[Stubby79]

Now that I can wrench under the hood without killing myself, I made and installed new motor cables:



Which eliminated 9 inches of "slack" in the motor loop and got rid of a questionable wire-to-lug joint I had recently noticed.

[Stubby79]

I drove her to work for the first time this evening.

The good news is I made it. The bad news is I wasn't sure I would, at times!

My field controller isn't working right...it's stopped increasing the field. Which is just odd, since it is still working at low field levels.

This means she's been gutless on take off. I had to actually shift gears to make up for it...which was hit or miss. That's something I will have to work on too.

On a positive note, it only took 14 amp-hours to get me here, 15km away. That's at least as good as my in-town driving, which was averaging 1ah/km. I guess all that stopping for red lights and what not works out to using at least as much power as blowing down the highway at 90km/hr. (I was really expecting to take an amp-hour hit taking it on the highway, especially since I have a 2km long hill of 6+ degrees along the way).

Motor wasn't hot. Warm, yes, but not hot. 40 centigrade. Brushes were hotter, but not insane.

More kinks to work out...looking forward to them coming to an end.

[Stubby79]

User error?

Sorta...not quite.

Why couldn't I bump up the field? Because the batteries were run down.

WTF.

Yeah, ok...I know from my e-bikes that if you leave the battery hooked up to the controller, it will run down the battery after a week or two...but it's only been a few days, and I have a heck of a lot more capacity here. Oy.

That's assuming it's the controller, since that's the only thing on this circuit.

On a good note, my 36v charger works fine on 220v. On a bad note, it only puts out 1.6 amps. Should only take a day and a half to charge them back up!

[Stubby79]

Drove her to work again last night. This time I had field control...a much better experience!

I could hear some arcing of the brushes at full speed, going up the hill on the highway. Increasing the field took car of it...but it also slowed me down. So I need to make it so the field automatically increases with speed (motor voltage), and I need to adjust the controller's maximum output voltage (which I purposefully set so that the motor doesn't over-rev and destroy itself) so I can have that extra bit of speed going up that hill.

When they say you need 96-volts or more for highway driving, they're right...I've limited mine to about 90v, and it's not quite enough (under a stronger field, anyway).

Anyway, it was a good drive. I only used 26ah for my 30km trip. Time to add another fuel log...

[Stubby79]

Didn't want to work on the electrical side of things today. Wanted to work on the car itself, so I "restored" the headlights with a 3M headlight restore kit.

What I started with:



500 grit: (remainder of lamination removed)


800 grit:


3000 grit, wet sanded:


Buffing compound:


Waxed, installed:


Parking lights on:


Opted to replace the LED headlight bulbs with apparently better ones, while I was at it. Had to re-arrange the wires to get them to work:


Decent output: