1968 Unisaw quit working

[woodcutter100]

Need some observations please. Using my saw to cut a board made the cut turned saw off to clear table. Planning to rip the board and no noise on the saw no hum nothing . Checked power to starter have 240 , checked power to switch have 240 any suggestions? it is a 1968 Unisaw and it has a Furnas starter original switch( 2 button start stop)

[Wild Turkey]

Clean out the switch.  Lots of fine sawdust can get into them and clog things up.

It's worked for me

[TDKPE]

What he said.  

You can also pop the cover off the box and push the starter in manually to see if the motor runs, but be careful as it's a line voltage motor control, so it's all hot and dangerous in there, including the push-button station if it's separate.

[woodcutter100]

Need some observations please. Using my saw to cut a board made the cut turned saw off to clear table. Planning to rip the board and no noise on the saw no hum nothing . Checked power to starter have 240 , checked power to switch have 240 any suggestions? it is a 1968 Unisaw and it has a Furnas starter original switch( 2 button start stop)

Blew dust out of all closed boxes including the motor still no luck
Thinking contactor any more thoughts?

[jteneyck]

Blew dust out of all closed boxes including the motor still no luck
Thinking contactor any more thoughts?

Did you try engaging the starter manually, as TDKPE suggested?  Use a piece of wood and push it in.  If it engages and the motor runs then something in the switch is bad.  

John

[woodcutter100]

Blew dust out of all closed boxes including the motor still no luck
Thinking contactor any more thoughts?

Thanks guys. I just engaged the contactor and it didn't stay in so I've got to find a replacement. Before I tried it just now it didn't have any reaction( like it didn't have power) but I knew there was power. You guys are the best. thanks again

[TDKPE]

Thanks guys. I just engaged the contactor and it didn't stay in so I've got to find a replacement.

But did the motor start?  It not staying in does not mean it's bad. 

If the stop button contacts are stuck open from dust (they're normally closed until you push the Stop button) the contactor inside the motor control will not latch itself closed, and the motor won't continue running.  There is probably a NEMA contactor in there with a set of auxiliary contacts mounted to it (smaller) for the latching function, with control wires to it, and which the Stop button releases when pressed by breaking the circuit to the coil on the main contactor.

There is a strong possibility there is nothing wrong with your motor control that some cleaning with compressed air won't cure.  Or even a loose wire.

That Furnas motor control is industrial strength.  I wouldn't toss it so quick without some more investigation.

[BloomingtonMike]

But did the motor start?  It not staying in does not mean it's bad. 

If the stop button contacts are stuck open from dust (they're normally closed until you push the Stop button) the contactor inside the motor control will not latch itself closed, and the motor won't continue running.  There is probably a NEMA contactor in there with a set of auxiliary contacts mounted to it (smaller) for the latching function, with control wires to it, and which the Stop button releases when pressed by breaking the circuit to the coil on the main contactor.

There is a strong possibility there is nothing wrong with your motor control that some cleaning with compressed air won't cure.  Or even a loose wire.

That Furnas motor control is industrial strength.  I wouldn't toss it so quick without some more investigation.

On older contactors, and good new contactors, many times the coil is replaceable too. Its worth doing more research. Could save you quite a few dollars and still have nice controls. IMO

Get out the meter

[Bob10]

I think they are about $60 on Amazon

[Stwood_]

Grizzly has universal switches also.