The company I work for is a small group - we do some specialized stuff for theme parks. A project we're on now requires some powder coating, and we haven't been happy with any of the quality from the powder coating shops we have tried, so we are doing it ourselves. We bought a small oven and set up a PID controller. The temps have been all over the places and the engineers are having some trouble getting it under control, the test batches have been baked too hot.
Enter me with the BBQ hobby...
Brought in my TP-20 and probes, got them set on the shelf. Discovered that the temps on the shelf are way off from the set temp. Green number below = set temp, red number below =actual temp the PID is measuring at the top of the oven, and the TP20 are the actual readings on the shelf where our material will be.
A bit hard to see in this photo, but:
SET TEMP (Green) = 370
MEASURED TEMP (Red) = 367
ACTUAL SHELF TEMPS (TP20) = 436 at the front of the oven, 491 at the back.
So we lower the PID probe closer to the shelf, and that brings us closer. But still a ~40-50 degree difference from the back of the oven to the front.
So I suggest we try indirect heat. Put an aluminum pan in (well, shoved is more accurate!) above the heating element to act as a deflector, and there is the magic ticket. We now have only a 4 degree difference between the front and back of the oven. We'll lower the PID probe closer to the shelf when we put parts in, and of course remove my temp probes! Pulled Pork wouldn't taste as good with powder coat chemicals mixed in.
We may also throw some sand into the pan to try and stabilize the oven a bit more.
Hope you enjoyed the read.
Enter me with the BBQ hobby...
Brought in my TP-20 and probes, got them set on the shelf. Discovered that the temps on the shelf are way off from the set temp. Green number below = set temp, red number below =actual temp the PID is measuring at the top of the oven, and the TP20 are the actual readings on the shelf where our material will be.
A bit hard to see in this photo, but:
SET TEMP (Green) = 370
MEASURED TEMP (Red) = 367
ACTUAL SHELF TEMPS (TP20) = 436 at the front of the oven, 491 at the back.
So we lower the PID probe closer to the shelf, and that brings us closer. But still a ~40-50 degree difference from the back of the oven to the front.
So I suggest we try indirect heat. Put an aluminum pan in (well, shoved is more accurate!) above the heating element to act as a deflector, and there is the magic ticket. We now have only a 4 degree difference between the front and back of the oven. We'll lower the PID probe closer to the shelf when we put parts in, and of course remove my temp probes! Pulled Pork wouldn't taste as good with powder coat chemicals mixed in.
We may also throw some sand into the pan to try and stabilize the oven a bit more.
Hope you enjoyed the read.