A friend if mine has given me a six inch buzzer in long term loan. I git it home the other day and gave it a bit of a going over. I discovered the motor start capacitor was stuffed so $50 later that was sorted. All the wiring had rubber insulation that was perished, so bext came a complete rewire.
Lastly rhe blades were very blunt. It came with a new set byt they weree the wrong size so I had to grind an 1/8th of an inch of the backs of them.
Put it all back together and it works great. Its missing a gaurd so thats my next task so that its a bit safer to use.
