As the grinder and other power tools wear out, sparking appears inside its body, which can be seen through the ventilation holes. If the problem is not eliminated, then the electric motor will fail quickly enough. You can eliminate sparking at home.
What you need:
- new brushes.
Grinder service process
It is necessary to unscrew the screws on the back handle of the grinder and open it. This will make the sparking even more noticeable when turned on.
Remove the brushes immediately and assess their wear.
Self-tapping screws are unscrewed from the side of the grinder gearbox to get to the rotor. This will allow you to inspect the removed manifold.
If it has a working out, then the lamellas will need to be pierced, leveling their plane. In addition, carbon deposits are also important, so it is necessary to grind the pads to a shine in any case. Before work, it is worth checking the armature and stator with a multimeter for a short circuit in the windings. (Read how to do this with a regular multimeter here – https://sdelaysam-svoimirukami.ru/5260-polnaja-proverka-rotora-jelektrodvigatelja.html)
Next, you need to disassemble the gearbox to remove the armature with the bearing.
There is a nut and a locknut on its shaft, which must be unscrewed.
Then it is knocked out of the gearbox housing with a plate. If it doesn’t come out in any way, you need to drill the impeller and get to the two screws located behind it. If you unscrew them, the rotor will come out of the housing.
Further, the bearings and the impeller are removed.
Then the manifold is machined on a lathe to flatten the plane. It is also worth polishing it.
(How to grind a manifold without a lathe read here – https://sdelaysam-svoimirukami.ru/5861-kak-protochit-kollektor-jakorja-jelektroinstrumenta-bez-tokarnogo-stanka.html)
After that, new bearings are installed, and the grinder is assembled back.
Then you need to put in fresh brushes. After that, there will be no more sparking on the manifold.
Watch the video