Wire fitting for brushes on elec motor

[ss]

Having sorted the issue with my chop saw bearings I decided to have a look at the back end of the elec motor and the wiring to the brushes are suspect. In this pic you can see the wire is pushed down the housing and acually emerges at the bottom touching the armature (?)

Pic 5 shows the spring holding the brush in place.

Pic 6 shows the wire squeezed down the side.

The wire on the other brush was just sitting on top and came loose.

It could be that when the bearings broke up the vibration dislodged the loose one.

Anyhow anyone know how I should connect them back to the brushes?

[Graham.]

Who's done that then?

The answer to your question is don't. Obtain a new pair of brushes.

[harry]

Those brushes look to need replacing.

There are various gizmos these days to disconnect brushes once a certain wear level is reached. It is to prevent undue sparking at the commutator as the spring tension reduces with wear on the brushes.

[John Rumm]

Almost looks like that brush was inserted upside down. I would stick a new set in and be done with it.

[ss]

You could be right but I will wait until I get the bearing to see it still works ok. I think the wiring was badly done at the factory as the wire to one of the brushes is just shoved down the side of the brush and emerges at the bottom and touches the revolving part of the motor, that doesnt appear to be correct (to me) and I know the saw has never been dismantled before.

[Tim+]

Don't think so. You can see the hole in the top of the brush in the second photo where the wire ought to be. It's been bodged badly by someone somewhere. As you say though, needs replacing whatever.

Tim

[Gefreiter Krueger]

Unless the wire is wrapped right round the brush, then it is most definitely upside down. The wire should be connected to the TOP.

[Frank Erskine]

The pigtails probably originally extended so far into the brushes. Now that the brushes have worn down the "wires" are showing, a bit like rivetted-on brake pads as they wear away.

Time for new brushes!

[Grimly Curmudgeon]

I'd say definitely. Quality control, eh? In the possible event of no replacements being available, I'd re-insert that one the right way up and it'd be good for a while yet.

[ss]

"Almost looks like that brush was inserted upside down. I would stick a new set in and be done with it."

The brush is not upside down, both brushes have like a small hole on top where the wire should be connected. The one that appears to be upside down has had the wire rammed down the side to make a connection. I believe these chop saws are made in China for B&Q so done cheap and anything goes. There is plenty of wear left on the brushes but will replace if the saw works ok after I replace the bearing as I dont like the wire connection.

[Grimly Curmudgeon]

Ah; a factory bodge to get it out the door. Must be ok, then.