Skill is a brand name and the true name for your item is a hand held electric circular saw. Three of the most common problems that occur with circular saws are bearing, switch and brush failures. The first thing to determine is the value of the saw and whether or not it is worth repairing.
If it is brush or switch failures check the following:
a. Make sure there isn't any unnecessary drag on the motor. Drag is the usual reason for brush and or switch failure. If there is the drag must be eliminated before continuing a repair.
b. Start by inspecting the bearings. If the saw has bushings it probably is not worth the effort to repair. If it has ball or pin bearings, getting them out is the next trick. If the bearing needing replacement is on a shaft or in a through hole it's a reasonably easy using a press or hammer and punch. If it is in a blind hole, use hydraulics to get it out by filling the inside of the bearing with grease and putting a shaft that just slides through the inside hole. Bang on the shaft and the grease will lift the bearing out of the hole. Be careful not to damage the bearing in the rreplacement process. Check to see that the bearing still turns free and that any seal on the bearing has not been damaged in the replacement process.
c. Visually check the commutator on the armature to see that it hasn't been damaged or shorted. To make sure the armature is ok, before ordering your brushes, bring the armature to an electric motor repair shop and have it tested.
d. Check the brush holders to see that they are still in good shape and not loose in there mounting. Make sure they are clean and smooth on the inside because dirt and damage to these holders can also cause overheating and premature brush failure. Often time’s sawdust can cause a brush to stick in the holder causing them to arc and overheat. If the brush holders are bent or burnt out then the connection springs will also be cooked and the unit is probably not worth repairing.
e. It’s possible that the brush holders are in good looking shape but that the heat incurred when brushes fail could have cooked the brush holder connection springs. You can tell if they are cooked by stretching them a little to see if they still have their elasticity. If they are cooked an electric motor repair shop would need to replace them because they are usually welded onto the field wires. They can’t be soldered because the solder would melt under the heat of normal operation.
f. Check the continuity of the switch with an Ohm meter. These switches are simple on off switches.
Once the previous conditions have been met then using the name, type and serial number of your saw, go to the internet and find a parts supplier for your saw. Order a switch or two brushes (a set) and replace them. You may want to order an extra set of brushes and from now on check them often, to see that they float unimpeded by wear or dust so you can replace them before they get to bad and cause expensive trouble.
Max B., November 2008
