Cut Motor Brushes

[jdlink01]

Hello All,
Anyone know of a retail store where I may be able to look to find replacement Cut motor brushes? I have no clue where to look and I dont want to pay for next day from Texas for $10 worth of brushes. Oh and its less than two weeks till Christmas and one of my machines decided to quit working. I'm thinking (and hoping) its the brushes. I know they havent been changed in a while and all the symptoms seem to be leading to the brushes being worn out.
Thanks for the help!
Josh

[chebytrk]

How many cut motor hours do you have? Have you checked the cut motor brushes to see how much wear is on them? What are the symptoms you're experiencing? Try to give us as much info as you can to help determine if in fact it is cut motor brushes that you need.

[fwharris]

Some have tried brushes for other sources with not very good luck. I think one even ended up with a burnt up cut motor. Your best bet is to order them from CarveWright.

[jdlink01]

Thanks guys. JerryB. I have 579 hours on my "old" machine which is only a year and a half old, and 140 hours on the "new" machine. I have had this problem before and I am 95% sure its the brushes. I pulled them out last night and there was nothing more than a nub left on them, and it has been 250 or so hours since I have changed them. The new machine is running like a champ. I bought it used with only 50 hours on it in August. Its Christmas time and if anything is going to break down its going to do it now in the middle of the rush. Thanks on the heads up on the brushes Floyd.
Josh

[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

[jdlink01]

Al,
Once again you are a wealth of information. Fortunately I was UNABLE to secure the exact brushes in my adventures this morning. Therfore no aftermarket brushes. Prior to starting my fruitless and ill advised trip out this morning I did place an order for several sets of new brushes knowing my second machine will be needing them in about 100 hours or so. I also ordered a long 1/16 inch carving bit to do my spoon carvings. Thanks for the info and advice guys!
Merry Christmas
Josh

[Digitalwoodshop]

Good Job !!!!

And I wish you luck with the new carving bit as it does open up new opportunity for the machine.

AL

[blhutchens]

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

So…..brushes are backordered at CW and won't be in till the end of the year. They are holding the rest of my order till they come in…..guess I will park #1 and wait.
You haven't found a source for them?

If one found some to fit or make fit, adjusted spring and tether accordingly ………would be better than running factory brushes to the spring…..as a temporary only.

[lynnfrwd]

Holding the whole order or sending partial now are both options. If you are in desperate need of carbon brushes, we have a few that we cannot sell to you as new, but could get you through till the end of the month.

[blhutchens]

Holding the whole order or sending partial now are both options. If you are in desperate need of carbon brushes, we have a few that we cannot sell to you as new, but could get you through till the end of the month.

I spoke with someone this afternoon after talking to you this morning and thought they were shipping….today.
I have another machine , but i am about to start a large project and would like to have both running at the onset.
I haven't looked at the 250hr brushes to see how bad they are but I will tomorrow.
i told him to ship and I would even pay shipping again on brushes!!

How do I order the used ones? and put the other ones on a separate order so it will ship?