10” x 30” lathe master electrical problem

Ok that is helpful but my motor does have 2 caps, a run and a start cap. The relay has 8 positions but only 6 are being used, Looking again at my drawing is it possible I have the load and neutral lines backwards?
 
OK you do have a dual cap motor. Four leads coming out + ground.
So what's the story with your start switch? Was it originally a push button and was replaced with a toggle? That would explain a lot
There should be both a start and a stop button on your machine
 
Yes I believe it had an emergency stop and yes I think they removed it and put the on/off toggle switch in its place
 
If you want to put it back to factory, you will need a momentary start button (normally open) and a momentary stop button (normally closed)
I suspect the relay latch function is not even working now the way it's kludged
 
That is what I was wondering about, if the overload relay was even working? I have been looking at schematics of all these over machines from 120v to 230v and many just wire directly into the drum switch, for some reason they put the drum after the relay. Could that be because they were worried that the drum switch could not handle the current? did they change the wiring on the motor?
something like this

fullsizeoutput_39.jpeg
 
Yes at this point I would like to just rewire it back to its original configuration, and I would like to set build the knee stop in as well. I am starting to re-draw the schematic, but I do not quite under stand how the overload relay works in the circuit.
 
OK understood. The relay (or contactor) serves two functions here: First, it does the heavy lifting as far as switching the motor current on and off (the reversing switch is normally not switched while power is applied) and second, it has a dedicated contact which latches the relay on until either the stop button or one of the safety switches opens, then it unlatches and stays off until restarted again. The relay also has a set of thermal elements which open the circuit if the motor is overloaded. I'm not sure if your relay has that, it's built-in and sometimes hard to tell.
The previous owner must have had a switch fail and was unable to get a replacement hence the toggle switch.
When you flip the power switch off does the motor turn off? Is it just giving an on/off action? None of your safety switches are wired in now, correct?
 
no none are wired in, I agree that that the relay may not have the thermal overload. Is it possible its just a contractor??? I have been reading most of the day about the motors and relays etc... I did take a pic of my motor and it is .75 HP RPM of 1680. Having a better understanding of the relay we will call it and looking at the CKT it appears the unit was turned on by the Drum Swt. I still have no idea where the mystery wire went.
 
Looking at it again SWT 1 would have had to be in the ON position to energize the coil on the relay. Once the coil was energized the guard swt would need to be closed so the neutral would be connected ( to what I don't know) could it have been just sitting touching the chassis which would have gone to Ground? But that would put a ground condition on connector 7 and 3 of the drum Swt, and on U1 of the Motor.
 
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