Originally Posted by
Digitalwoodshop
It is my opinion that you should only use the LHR Brushes and just bite the bullet and add a few things like a extra FSC Cable or two and a board sensor. That will make the shipping a little easier to justify. It is good you have 2 machines, that takes some of the stress off of getting things made.
As posted above, some have purchased brushes and posted a "Pat on the Back" for themselves only to post later... "I burned up my Cut Motor..."
I have years working with Carbon Brushes going all the way back to 1977 my first Navy Fire Control System where we actually replaced brushes on motors and did maintenance. Mostly in Amplydyne Generators... but the point, I have learned a few things about brushes....
1. Not all Carbon Brushes are the same... First is the Hardness of the Carbon... Second is the length of the Spring and tether copper wire in the center. I believe the guy that had the motor burn up the tether was LONGER on the Generic Brush. The Spring and Tether do 2 functions.. Provide PRESSURE and I believe the spring was LONGER and HENCE, Scrunched up inside the shorter area of the LHR Brush Holder provided MORE Pressure on the brush and Copper Commutator. This HEAVIER pressure caused the brush to wear out QUICKER and to GRIND down the COPPER of the Commutator. So that is BAD ENOUGH... Then we have the Tether LENGTH... LHR Brushes have a EXACT Length that acts like a DOG LEASH to STOP the Metal Parts of the Carbon Brushes from reaching the Moving Copper Parts.... Imagine doing a project and the Brush wearing out and the METAL SPRING making contact with the spining parts.... WE are talking BIG SPARKS.... Likely causing a FIRE, Likely burning out the X Termination Board and it's Q1 Cut Motor Switch Circuit...
So now... that LHR Shipping charge is looking much better than the Hundreds in damage and possible FIRE in your shop....
OK... THAT is the Worst Possible Case..... But food for thought....
As Clint would say.... "Do you feel Lucky" that you would find a METRIC Carbon Brush at ACE Hardware that matches the LHR Brush in ALL ways... Sure you could Sand Paper down a bigger brush to fit... But what about the Spring and Teather....
The Pictue of the WORN Copper Commutator is about 1000 Cut Hours and I retired that Armature after about 5 Brush Changes. Once the Copper is GONE.... Your in for a new motor...
AL