Identifying motor type and guidance on how to build controller
As i can no longer &quot;toggle&quot; the switch i simply want the grinder to turn on when the power switch is flicked. Simple as that. Would i be able to jump what i assume is a relay?

You can probably do that. You can probably trace the connections to the PCB and verify that the motor is connected to power when the relay is energized. However it appears to me that the thermal protection mentioned on the motor label is something that is connected to the PCB. If you simply bypass the relay, you will remove that protection.
The protection may be something that can be simply connected in series with the relay. There is a possibility that has failed and the problem with the PCB is that it starts the motor then shuts it off because the failed thermal protection makes it appear that the motor has overheated. You should use an ohmmeter to check the pair of brown wires coming from the motor to a corner of the PCB to determine if it is a closed switch or something else. If it is an open circuit, there it has probably failed. Also try to trace what they are connected to on the PCB.

... the one second interval is way too short ... Could this be signs of a faulty capacitor?

It could be. It could be a sign of something else as I said above. It could also be some other failure on the board.