Went away for a week and finally had time to finish this up on Sunday.
Total cost of new parts was $125 + another $20 or so for miscellaneous (mostly a roll of 14/3 wire).
Took a good chunk of the day to get it done but a lot of that was me being excessive --- and then there is the two trips to the store 'cause I bought the wrong stuff the first time.
Mounting the parts - I was able to reuse the prior hole for the meter for the SSR and its heatsink, square parts and a round hole but it was big enough to clear the SSR base and small enough to cover with the heatsink. The SSR (solid state relay) bolts directly to the heatsink but stays inside the cabinet making the hook up easier.
The 2 pole power switch needed a .85 round hole and I had to use the small rectangle hole that used to be for the indicator light. For that I made to sheet metal washers big enough to cover the indicator light hole with a proper sized center hold for the switch - On the lathe and fussing too much. Sure looks nice though!
The controller needed a nice clean new square hole (about 1.8 each side). I did that with my rotary tool and a tiny cut off disk.
This part of the project would have been a lot easier if I'd had a few sheet metal tools.....
The wire up followed diagram in the manual for the controller, no rocket science here just paying attention and understanding it. I did hook stuff up in stages so make sure it was working along the way. First power to the 2 pole switch and its light and then to the controller. Made sure the switch light worked and the controller fired up. Then hooked up the thermocouple to the controller. I did not know thermocouples have a + and - terminal. If you get it backwards the temp will go down when instead of up. So I verified that with a heat gun on the thermocouple after hooking it up to the controller. Last was the SSR and the heating elements. Verified that the controller was turning the SSR on (SSR has a led indicator). They suggested running a light bulb to make sure the SSR is working but at that point I knew the rest was good so just went with the heater coils and it worked just fine. I set the temp to 200 F for the first run.
The install:
wiring:
The stuff that came out:
As far as setting up the controller, I used its auto-tune feature and it worked out great. There wasn't a lot of guidance about what conditions you need to setup before firing off the auto-tune. However it's easy enough that I was able to work out the best approach.
What I ended up doing was setting the kiln at 1450F (typical enameling temp) and letting it soak for a good long time so it was fully warmed up. I then opened the door and let the temp drop about 350 degrees and fired off the auto-tune. I came to this after a couple other rounds of auto-tuning. Basically, I want it to work well (recover quickly and not overshoot) on my most demanding use. When enameling you are frequently opening up the kiln and putting something in that you want to hit a temp and hold for a few minutes and then remove it.
Every other use I could think of (the hobby heat treating I do) really isn't that demanding. You just want a fixed temp and you want to hold it for a reasonably long soak temp. In that case the response and recovery time is not really all that critical, you're just going to leave the part in there for 15 - 30 minutes anyway.
OK - well if you read all the way to this point, I've got the worlds most boring video for you!! It demonstrates how well the controller works for the enamel case - with very little fussing on my part.
Really happy with how the worked out. Being able to punch in a temp and walk away is so much nicer than trying to find the right dial setting and having to keep adjusting it as the kiln warms up.