commutator on grinder.

[lexi]

Small 4 1/2" Blue Bosch 700 watt has a worn commutator. There are 5 segments off it and it is well worn down, but it still works. Can it be saved? Cheap copper commutator from China? Anyone done it? Don't know if the copper section presses off or the whole shaft has to be renewed. It is a great size and would like to repair it. Would a Bosch part be uneconomical?

 

[rtbcomp]

You need to disconnect and reconnect the armature windings too don't forget.

 

[brightspark]

bin it unless u like wasting time with no end result

 

[pedrobedro]

You need to disconnect and reconnect the armature windings too don't forget.

I can pull the commutator out of my grinder without disturbing the armature, just need to take the carbon brushes out.

 

[lexi]

All the time in the world to fix it...........if it can be done. Bin it does not appeal........my workshop is full of stuff that has been repaired. I seem to get more pleasure from that. It may come from previously owning Land Rovers

 

[brightspark]

I can pull the commutator out of my grinder without disturbing the armature, just need to take the carbon brushes out.

don't u mean the field coils armature is a commutator

 

[RichardM]

Check our Bosch spare parts prices, they're on the net

 

[lexi]

Searching around,I don't think it can be fixed with a mere commutator part. It would need the whole shaft with armature the lot. Less the copper cylinder can be cut and pulled off the shaft and a chinese one put on and soldered to armature. Will use it meanwhile and keep an eye on eblag for a NOS unit. I did check some Bosch sites in USA and not available. This one was only £8 and feels better than my 2 Hitachi 4 1/2" new models. It is only for intermittent work with one specific blade.
Daft thing is that about 7 years ago I bought a blue Bosch new and it lasted just over a year. I binned the thing and it may have provided parts for this. See when you are busy, you throw away......business expense, time is money, all that stuff. Thank God, every day is play day now

 

[brightspark]

bin it

 

[jordan1]

Don't know how it's running with all those segments missing off the armature

 

[brightspark]

Don't know how it's running with all those segments missing off the armature

very slow jumping the bad segments and burning sparking

 

[tlovatt]

How many segments does it have in total?
The com will be difficult to replace as it is not just physically getting it off and on the shaft but making all of the connections and reinsulating appropriately.

 

[lexi]

bin it

No way.........I have to show it who is Bosch

 

[lexi]

How many segments does it have in total?
The com will be difficult to replace as it is not just physically getting it off and on the shaft but making all of the connections and reinsulating appropriately.

Maybe about 15? Yeah, only a new shaft with armature the lot will make it good. It will be my classic grinder?
Still searching for 2 correct poppet valves for a Nilfisk wobble pump......they are out there somewhere.

 

[zzr1200]

No way.........I have to show it who is Bosch

Posting is useless without pictures, but I suspect brightspark has the right answer.

Metabo is the way to go...

 

[pedrobedro]

Metabo is the way to go...

I replaced my cheap grinders with a Metabo. Heavy duty and last for years, already has done.