Motor Brush Upgrade/Modification. Can it be Done?

[bigcaddy]

I started a thread today about a Dumore hand grinder that resisted attempts at coming apart.

Now that I have it broken down, I wanted to replace the brushes. They are a bit worn but a new set is a cheap investment to eliminate a replacement shortly down the road.

My question is this: Can I remove the old brushes, which are simply carbon plugs with a spring pressed onto them, and replace them with the newer style ones that have the braided copper wire attached to both the brush and end cap?

This Dumore is really old and I don't think I'll be able to find those exact brushes again. I could go by a electrical supply and see what they have but I wanted to know if any fellow members on here have modified them before.

Other then retaining the brush from bouncing around the motor when worn and enhanced electrical conduction, what purpose does that copper wire serve?

 

[A_Pmech]

Brushes are easy to modify with sandpaper.

The newer design brushes with the captured spring should work for you if they'll fit in the brush holders.

The purpose of the pigtail is to transfer power to the brush rather than allowing it to go through the spring which will cause it to heat and lose it's temper.

 

[bigcaddy]

Brushes are easy to modify with sandpaper.

The newer design brushes with the captured spring should work for you if they'll fit in the brush holders.

The purpose of the pigtail is to transfer power to the brush rather than allowing it to go through the spring which will cause it to heat and lose it's temper.

Thanks. I'll get some measurments and compare to what Du-More is offering for sale. If it fits, I'll get a new set and upgrade the bearings while its apart. Might was well make it a hot rod while its in pieces.