Jim Yanik wrote in message
4...
"Stephen" wrote in
o.uk:

Hi.

I got a Titan circular saw from Screwfix a couple of years ago.

The brushes had worn down to the springs about a year ago. I had
contacted Screwfix who then directed me to a spare parts supplier. I
then bought a new set of brushes. I have since installed these.

Ever since then I've always had a lot more blue sparking from the
commutator (visible through the ventilation vents). I put this down to
the brushes bedding in from a flat surface to a curved one.

Now tonight, whilst cutting pallets, I now have yellow sparks coming
from the other end of the motor.......

Is this something I should be concerned about? What is causing it? is
it repairable or shall I need a new circular saw?

Stephen.




I had a similar problem with my Makita 6095 drill/driver. (blue sparking)
I used CRC MAF-sensor spray cleaner to wash out the powdered graphite on
the commutator tht was left over from the worn brushes. No more sparking.

yellow sparking would seem to indicate some sort of ferrous metal burning.
maybe it needs lube,if the bearings aren't too far gone.

--
Jim Yanik
jyanik
at
localnet
dot com


Or shorts to the iron of rotor or stator which explains the original and
replacement brushes, blue sparks from excess rotor current