Recent content by MarkN

I had variable speed control before. This time I adjusted the algorithm a little in terms of not stopping the fan completely when it hit the desired temp. The reason my temps fluctuated more before was due to the poor placement of the temp probe. The graph is a moving average of temps collected...

This is my 2nd cook using SnowBlower after some adjustments: - placed the pit temp probe at the top of the lid (where the handle screws in). The placement last time was dumb as I just stuck it through the vent hole and there was too much fluctuation. - variable fan speed adjusted so it doesn't...

PCB layout. Can't wait for my order to arrive so I can assemble :).

Can you explain the logic behind the algorithm used to maintain temps? I assume the fan speed varies with temperature. How often are temps measured and how often does it adjust the fan & damper? How precise is the flat line (plus/minus 5 degrees?)? How variable are the fan speeds adjusted? How...

Interesting. I'm curious how often overshoots are a problem? Is this happening because the fan is still on when the lid is open? I have servo motors and a 3D printer, but was not planning on dusting that off for this project. I guess I could if I run into an overshoot issue.

Thanks. I used a Cusinart COS-118. I had a WSM18 years ago that I gave to my cousin. I recently got interested in smoking again (thus my long absence from this forum). Picked up the Cuisinart for $55.66 shipped and have not looked back. Food taste the same as cooking on a WSM (athough the...

Thanks for your feedback @HuangFeng. 1. The variable speed control was actually easier than I expected using PWM (pulse width modulation). Fancy name but it's a capability built-into the ESP32. My algorithm was simple: subtract the pit_temp from the desired_temp. Then multiply this value by 10%...

First cook was today and it turned out successful. My temps were not as tight as I had hoped, and I also added variable fan speed control, but I need to tune my algorithm a bit. Probe 1 is a brisket point, probe 2 is a brisket flat, and probe 3 is a pork shoulder. I pulled it at the stall and...

I just looked up the price of a Raspberry Pi. Wow, didn't know they went up so much. I have 5 of them collecting dust. I decided to go with the ESP32 due to its lower power consumption.

Hello everyone, I just built a fun DIY temperature control system and would love your feedback to improve it. It's usable, but I'm wondering what other features I should add? Here are my capabilities so far. What would you add/change that would make a noticeable difference in results? I like the...

Looks great Rob!! Have you plotted the temperature? I would love to see the graph. What range are you getting? 10 degrees? Sadly, I have not had a chance to work on mine yet. I think I will continue to try an explore the variable voltage/fan speed. Unfortunately it probably would be very...

Joe, Ideally, my intent was to keep SCATS under $20. If we find the right thermistor and fan, this solution should be very usable. We will definitely post the part numbers and where to get everything once we have solidified the design. Interchanging thermistors would also be an option if you...

Rob, I have not built it yet. I'm under the weather and feel like crap. I have all the parts but probably won't get around to it until a couple more days of rest. I guess SCATS will have to wait. -mark

I don't have any suggestions for a coating for the therm leads. Hopefully it will work out okay. At least the sensor is coated. For the fan, I assume that some air must be allowed to flow even while the fan is off (otherwise the flame would die). Hopefully the airflow permitted by the fan...

I bought this off ebay. I found a couple on alliedelec.com that would work, but they charge $5 handling and $x.xx for shipping. So I didn't bother when i could get three for under $5 on ebay. The one on digi-key was not available. The resistance jumps to 10K ohms at 130C. It starts to...