Ben's Elec-Trak

[Christ]

Waiting out for the pics!

[Hondo]

Ben, you have really motivated me. I hate mowing my yard with a noisy ice powered rider, and it takes so long (about 1 1/2 hours with a 38" cutting deck). Since my boys are grown & gone, I realized that I will be mowing my yard myself for the rest of my life. Since that's the case, I decided to build a MANLY MOWER!!! I found a golf course mower on ebay for $200 that has a 7 foot cutting swath! I picked it up on Sunday and am in the process of cleaning and greasing all the bearings and sharpening the blades (reel type). I am going to put the same motor on it that I have in my Fiero and enough batteries to mow the yard completely in one charge. I should probably start a new thread on this with pictures. Thanks for the motivation!

Hondo

[bennelson]

Hondo, please do start a new thread for your mower!

I am sure I speak for everyone when I say that we would all love to see photos and hear the chronicle tale of your mower work!

Also, see if you can make it down to Milwaukee sometime when we are doing an EV Build Day! (1st and 3rd Sunday of the month)

Both Daox and I are currently working on electric riders. We could have a E-Rider Rally! Drag racing may be involved...


EDIT:
Well, the good news is that I got the blade motors more or less rebuilt and installed. I got the mower deck back on and went for a test drive.

The mower seemed to mow fairly well, but the drive motor was really straining. After driving around a few minutes, it started getting pretty hot. Looks like I have to pull the drive motor apart now!!!!

EDIT EDIT:
I have some photos up now at:
http://gallery.me.com/benhdvideoguy#101591

[bennelson]

OH NO!

I pulled the drive motor apart.

Part of the permanent magnet inside is broken! It must have been rubbing against the armature heating everything up! A piece a bit smaller than an inch square completely broke off.

I believe that this is the one part of the motor can can NOT simply paint, clean-up, or replace! It is a special part epoxied straight to the middle of the iron shell of the motor!

[Hondo]

could you possibly epoxy it back in place? If you used JB weld or something similar, it might hold up. It shouldn't matter if that much if the magnet is broken as long as you can put it tightly right back where it was. Otherwise I know of a working electric fork lift near Madison that might be able to be bought for $300. Lots of extra parts!

Hondo

[bennelson]

I e-mailed an EV buddy, and he mentioned that it might be possible to epoxy the chunk o' magnet back in place - so it might be possible. Going to be a big pain in the butt no matter what though!

Here are some photos of what I did this morning (BEFORE breaking the motor...)


Blade motor, ready to sand down.


Blade motor, mostly sanded.


Blade motor, getting a coat of primer, recycled yogurt container keeping paint off the permanent magnets.


New drive-end bearing.


Motor armature with new drive-end and commutator-end bearings


Mower deck up on 5-gallon buckets for testing. One blade motor repainted. It wasn't totally dry when I handled it, so some of the blue paper shop towels got stuck to it!


This is those funky bearings that the steering uses. The grey steel part was completely rusted away on the original bearings. These new ones look much nicer.

I am still very GRRR about the drive motor magnet breaking.... GRRR...

[bennelson]

Well, here's that broken piece of the magnet.



I had a chance to stop by the forklift rebuilding place today, and I spoke with one of the technicians there. He said that a smaller chunk of magnet breaking off really isn't that big of a deal. It shouldn't make that much of a difference in the overall magnet field. The bigger issue is that the rest of the magnet is still nicely glued to the shell of the motor, which it appears to be.

He said that sometimes, motors can get hot enough for the epoxy to soften, and the magnet actually rotates a little bit inside the shell, and messes up the timing.

I cleaned up the motor as best I could.
It has new bearings, and I green scrubbied the commutator to remove any surface corrosion there.


Cleaned up commutator and new bearing.


Drive end and bearing.



Drive motor armature.


I put the entire motor back together and re-installed the motor, pulley, and belt. I filled the rear tires with air (even though it won't hold more than a few hours) and did some test mowing.

The drive motor does get hot. Not nearly as bad as it did the other night, but the fact that it gets warm at all is a problem. I was able to mow most of my yard, but I didn't want to abuse the motor too much, and my batteries were running low anyways.

I hooked up a couple chargers to the mower and will finish mowing tomorrow. Seems like the next EV Build Day can't come soon enough. I really need to have the guys take a look at this thing and see what we can figure out.

It would also be great to put a clamp-on ammeter on the mower to see how many amps it's pulling.

[Christ]

It's Alive!!!!

Good to hear that it's going together smoothly... I wish my projects were like this.

[bennelson]

The drive motor COMPLETELY stopped working last time I drove the mower.

Sounds like something shorted inside the motor. I am guessing more magnet broke loose, jammed the motor, and turned the whole thing into a 36V heater.

Time for a new motor.....

[Daox]

Yikes! That kind of stinks. Are you going to try and find an OEM replacement, or rig up some other motor to work?

See you this Sunday?