Electrical issues on house current baffles me at times.....

[Cranky]

The latest is a metal chop saw that was working fine but 'hides' on the floor under a work bench. Got it out a few days ago and it wouldn't work after working fine a few months ago. After getting it out and on a work table it wouldn't turn on so started taking the handle apart to check for things wrong and didn't see anything and was planning on buying a new multimeter to check the switch since my old one is over 50 years old and needed an external power source. Low and behold before buying a new multimeter, all of a sudden it works! I'm guessing the switch needed to be 'worked' some more....? Thing is it's been sitting on my work stand for a few days which is under my carport and in a damp area and the first time to plug it in again, it worked.....!

 

[kiwigtx]

I'm guessing the switch needed to be 'worked' some more....?

Sounds about right if the saw has been stored in the damp for a long time. Operate the switch a few times....should be OK.

Make sure your plug connections are in good order also....and flexible cord is not cracked, broken or perished...depending on what it's made of.

 

[Triplegreen500]

Most switches nowadays are plastic. Contacts are - obviously - metal. Plastic can crack or get weak/warped; metal can corrode. Pull apart the main power switch and see if it's tight, or if it's loose and/or corroded. Dielectric grease is your friend - grease 'er up before reassembly, regardless. If it IS corroded, hit it with some 80 grit and make it shiny again first.

If the switch looks ok, bypass it by wiring around it and see if the motor fires. If it still acts up, your motor windings are likely corroded.

And of course, keep an eye out for damaged wires - dry rot, rodents, etc.

Yes - get a new multimeter. ALWAYS have one handy. For $19 for a cheap one...it can save HOURS of troubleshooting! I keep a cheap one I can use at work, and have a Fluke I use for my own projects where nobody else can get hands on it or make it wander off.

 

[bandit67]

The carbon brushes sometimes lose contact at the stator/armature point. Dust, crud, and worn/loose springs all can add to a no start, and then starting.