lathe again

[bubblejunky]

I ordered the cobra lathe and was wondering if I need the cutting oil also. Also maybe some tips on cutting comms like how to center the arm in the can with the shims. I read the article in rcca about the p2k and all that they recommend. Do I need to get a brush hood alignment tool? Bearing buster drops? Diamond bit eventually? etc, etc

[Leet TC3]

Generally speaking arms are centered when they come from the factory. But if you want to check, or if you have gotten a new can etc, here is how to center the arm:

1. Remove all shims from the arm, put it back in the can and put the endbell on.

2. Place the motor on a flat surface and spin the arm with your fingers a few times. This will center the arm in the magnets.

3. Pull on the shaft (NO jokes please :D ) and note any slack. Open the motor and add shims to the lower part of the arm to remove this slack.

4. Repeat #2

5. Push on the shaft and note any slack. Open the motor and add shims to remove MOST of the slack. The shaft should move -just a little-. If it doesn't move at all, the arm will be rubbing on the bearings/bushings and wear them out quickly. If there is too much slack, the motor will shift up and down too much and rob you of horse power.

I would say forget about brush alignements. Any reputable motor manufacturer will have brush hoods in perfect alignment.

The bushing buster drops are a good idea - this is a suspension liquid with an abrasive that is great for breaking in bushings. But only use it when breaking in new bushings. If you use it all the time your bushings will wear out quickly.

[noobie]

Personally, I align the brushes. I have seen stock ones that are definitely out. I don't use a tool, though. I check the wear on the brushes and adjust accordingly until the wear mark is on the center of the brush.

[tc3guy]

dcommerce,
good choice. heres a tip
1. turn the lathe on then take a black sharpie markie to it until the entire thing is black. that way youll know your comm is true when all the ink is gone. you wont need the bearing buster drops unless your motor is new. the brush alignement thing is handy but you dont need it unless youre a serious racer. The diamond bit is nice because it lasts long but its pretty expensive. just stay with carbide bits until you know what your doing.