My Poor Chop Saw- All Sparky McSparky- any ideas?

[Noel]

Old(ish) Elektra Beckum KG 210 chop saw. Has been great over the years, light and compact but now all fluttery and sparky.
Brushes seem ok, pulled it apart and cleaned up the commutator and blew out dust and stuff from the armature and frame but still rather poorly.
Short on the windings/armature or something else? Fixable (or worth fixing)?

Short video: https://sendvid.com/kgmhqrbw

TIA.

Noel

 

[banjerbill]

This happened to my friends Electra chop saw. Although there was lots of brush length they were not contacting properly. I managed a temporary fix by turning them over but we had to replace in the end. Can't recall where the replacements came from but it was in the Southampton area. I found them with a Google search quite easily.

Bill

 

[Rob B]

I repaired washing machines for 30+years and this happened often. I'd clean the com with a com stick if it was pitted but usually just a wipe with a rag then new brushes. They might spark a little until they bed in and last another few years but never as long as the originals.
HTH
Rob

 

[Racers]

Looks like a short on the armature to me, do have a meter to test the windings?

Same thing happened on my dyson £20 for a replacement wasn't to bad I guess yours will be more expensive.

Brushes are just carbon you can file them to fit.

Pete

 

[Noel]

Thanks Bill, Rob and Pete. I'll see if I can get some new brushes and work out how to test the armature. I have a meter.
Many thanks.

 

[Racers]

The windings are connected across the rotor so put your probes on the contacts 180 degrees apart and see if you get a lower or no reading on any winding.

Pete

 

[Noel]

The windings are connected across the rotor so put your probes on the contacts 180 degrees apart and see if you get a lower or no reading on any winding.

Pete

Thanks Pete. Have been reading up about that and watching a few videos. Will futter about at the weekend and see what I can find.

 

[Myfordman]

A general rule is that if the Sparks are along the edge of the brush where meet the commutator then suspect cleanliness, brush length and pressure and freedom to slide in the holders.
If the spark run in rings around the commutator, the armature is fubar and often not economically repairable unless you are lucky.

 

[Noel]

Thanks 9f, haven't looked at it since but hope to do so soon. Not too apparent in the video but sparks may well go all the way 'round. I suspect it is a goner but we'll see.