Part 3:

and you will have to rethread it before you can operate the griddle again.

The controller holds contact points together until the set temp is reached, and then a bi-metal in the temp probe causes the contacts to open/current flow to be cutoff to the heating elements.

My advice is to abandon the griddle if you have ANY doubts about your ability to successfully modify/operate it safely, as there is a significant amount of risk involved if you don't pay VERY close attention to the griddle as you operate it/after you modify it.

You could also purchase (ebay) a cheap (but quality/used) Omega thermocouple temperature controller that has a plug to plug in the cord to the griddle (and a SSR (Solid State Relay), wire the griddle up direct (to the heating elements/bypassing the Presto's controller/or modify the griddle as above, and just crank it up to "600 (where 600 would be if it were on the dial)) and use that to control current to the griddle/the
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