why dont tools last any more

[Thingybob]

You just have to look at an ELU routers against the stuff produced today had mine since 90s and the small one i bought 2 years ago (won't name brand )2 weeks in the plunge lock arm sliped around the nut holding it PLASTIC !
Made a new one in perspex at least its harder than polythene

 

[flying haggis]

i actually did clean between the segments , perhaps it doesnt show very well

 

[Jonzjob]

It's called undercutting and an old full size hacksaw blade does a good job on that. If you wrap some of your wet&dry around the armature it's a good idea to fit the brushes and use the abrasive to 'bed' the brushes in. That way they make full contact across the complete surface and much less likely to arc. That takes me back to my R.A.F aircraft eleky days when we were taught how to do things like that

 

[flying haggis]

It's called undercutting and an old full size hacksaw blade does a good job on that. If you wrap some of your wet&dry around the armature it's a good idea to fit the brushes and use the abrasive to 'bed' the brushes in. That way they make full contact across the complete surface and much less likely to arc. That takes me back to my R.A.F aircraft eleky days when we were taught how to do things like that

i didnt wrap the wet and dry round the armature but i did scrape out the grooves. My dad was a REME electrician and I remember him doing the hacksaw blade between the segments when rebuilding dynamos and startermoters from landrovers and bedford trucks