Help on fault finding on a C3-31 Hammer combination machine

[OMLCNC]

Testing is not proceeding in a logical manner.

Personally, I would install the original contactor first.
With the machine disconnected from supply, manually operate the contactor and confirm, using an ohmmeter, that all the contacts operate as expected.

No they do not.

(1 and 2) and (3 and 4) closed all the time (NO) even if you manually opperate contactor.
ONLY when Planer and Spindle Moulder selected.

When Saw selected all contacts operate as expected.

Plug the machine in and press start and see if the contactor pulls in and holds
Now with a voltmeter I would test to see if we are getting 3 phases (full voltage) at the disconnected motor leads.

Yes it pulls in and holds.
Yes 440v - 460v out of three wires at plug to motor.

Does this point to item 10 the selector switch?
The Saw does not operate correctly all the time, it still makes the contactors chatter.
If that helps.

If you then press stop, there should be DC across 2 of the motor wires for several seconds (it makes a loud humming noise under normal conditions)

If your machine works in a similar way to mine, if an e/stop button is pressed and you press 'start', then the braking system energises for several seconds just as during a normal stop.
This means that if the contactor, and it's contacts, are not working correctly it may be possible to initiate the brake during startup. This is the main reason
I would refit the original contactor and auxiliary as there may be some time delay involved here.
The drawing is one of the worst I've seen and it's not easy, for me anyway, to determine exactly what's going on, and I've used some complex drawing in the past.

I've attached a copy of the single phase version if it helps sort this out, (not studied it yet though)

Yes I get the loud humming noise when I stop the machine.
Here is a picture of the original contacts and auxiliary, I've split them apart so you can see the information.
I can not see that they have a 1 second delay, can you?