[trops357]

Hey, I wasnt sure just how free the brush was designed to move in the brush holder/guide. I shot a short video of the cleaned brush.
Let me know if you think it is moving free enough, or if I sanded too much, lol.
Got the motor appart, cleaned it up with degreaser , tarn-x, local carwash preasure wash. 800 wet sandpaper.

Thanks for taking time to look.

BTW: It has 75 bars on the communtator.

http://www.youtube.com/watch?v=nYhe6PPfyGU&feature=channel

 

[trops357]

It is most likely good enough but I would try to do a little better. It seems a tiny bit stiff as a starting point though it seems to work pretty well with the spring.

I generally wipe out the inside of the holder (where the brush goes) with some scotchbright and make sure there is no corrosion lumps of bumps inside. Then I might give each side of the brush a single pass or 2 on a piece of fine sandpaper. I would do that dry because I want the leave some graphite dust for lubrication.

Ok, I will go over the holder better, I didnt use the sandpapper wet, I have just heard a lot of people refer to it as wet sandpapper.
Thanks for the info!!!

 

[trops357]

Yeah, it appears to be able to move smoothly all the way with the spring force. I'd use it. The brush face is the part which contacts the commutator. So be sure to shape it to the comm diameter upon installation. I'd wrap crocus cloth around the comm and "drum sand" all 4 brushes to the comm diameter. Then use a commercially available dressing stone while running the motor at 12 volts to finish the shaping process. Then run it for hours to seat the brushes and film the comm.

While you're going through this process, check often to see if each brush is free to move radially back and forth by pulling it up by the pigtails. If the pigtails can't withstand that much pull force, they would soon fail from a high current pulse anyway.

major

Yeah, I thought it might be a good idea to dosomething like put sandpapper on the communtator,(rough side up,lol), and sand the brush into shape. My partner said the brush would take shape on its own.

I am not sure how to get crocus cloth or the dressing stone in the area to be shaped w/o the motor being apart?? I must not be visualizing it correct.

 

[trops357]

Hi trops,


major

Thank you very much for the details!! Its a cool day outside, gonna be perfect for tinkering on the motor!!!