just cut my first comm!
 

i just got my hudy advanced comm lathe and i just made my first cut, it came out get and the lathe is worth every single penny! that only problem im having is when i turn the lathe on the armature slides down and rides against the blocks that the V groove is in, it rides on the side that the comm is on and it scraped some of the black powercoating off the block but i dont think it matters does it? or should the armature be complety in the open?

Congratulations.


I dont have the same lathe, but on my Eagle lathe i use a collar to keep the arm from sliding side to side on the blocks.

you need to shim the motor accordingly....i usually take the big shim off the comm side of the armature and put 1 or 2 metal shims onto there to stop it rubbing against the blocks.you dont want to tight or it wont turn properly, just allow a tiny bit of movement.

cool thanks, i will use some brass spacers that i have to i will get barley any resistance when it spins against that block, and one more thing, should the comm look like a mirror after a cut? my look very very close but when i put it under a 10x jewlers loop i have you can see very fine lines on the surface

well, it sound like you comm is fine :)

Sounds like it cut perfectly. Those small lines actually aid in brush break in. If it leaves a mirror finish on after a cut, it takes forever to break in the brush.

I had the same problem with the comm rubbing up against the block. I didn't notice it on time and found I had a rather deep grove cut into the block. I would not use any metal shims as you will still have metal on metal rubbing. I have been using plastic washers for about 2 years now and have not notice any further wear. I use the Associated plastic shims that they use to change the wheel base of their vehicles. They fit the motor shaft perfectly.

Here's what you should do. Take a small pinion gear, a teflon or brass washer and the big fiber shim above the comm. The place the fiber shim on the other side of the arm and push it against the arm until it can't move. Then place the arm in the blocks. Take the teflon washer and push in on the shaft. Us the pinion gear to secure and prevent movement. You should have 0 play in the rotating armature.

just use one of your motor washers on the comm side. when you are cutting your comm place your finger against the end of the armature. (opposite side of the comm) lightly. actually just resting your finger on the end to keep the comm from moving. add a drop of oil on your v-blocks. when you did your last cut did you use a sharpie marking pen. i use WD-40 when i make my last cut. i use a small paint brush to put a drop on the comm and then make the last cut.