Modified my electric smoker

[RocketMan]

A few years ago my folks gave me an electric smoker.  I finally got around to using it earlier this year, a couple of batches of beef jerky being the first thing I tried making.  The jerky didn't turn out too well because the smoker gets too hot.  There is no temperature control, so it runs full on as soon as it is plugged in.  Because of that it was essentially cooking the meat, not drying it.
So, I have remedied that problem.  Using a small temp controller purchased off eBay, a solid state relay, and a type 'k' thermocouple, I now have complete control over the temperature in the smoker.  It should work pretty well for whatever we use it for from this point forward.
The temp controller was not actually as advertised, being for 220VAC operation, not usable with SSRs, and not being settable for °F.  But that didn't matter much.  A few hacks later it runs off 12VAC (from a small stepdown transformer inside the project box) and works with SSRs just fine.  I can easily do °C to °F conversions, so that isn't an issue.  Temperatures control typically to about ±1°C after using the autotune function built-in to the controller.  Not bad for a cheap Chinese clone of a Japanese controller.
Here is the end result of the little project.

The temperature control unit itself:


The back of the control unit where the thermocouple plugs in:


Here is the smoker itself.



Here is a close shot of the top of the smoker showing the tubing connectors used as ports for the thermocouple and the small digital thermometer used to confirm the temperature.


We have some round steak thawing as I type this, preparing for the next batch of jerky.

[AmbulanceDriver]

I've seen some similar devices (production built) for charcoal smokers.  We're talking crazy levels of sophistication for what is really a very simple process...  :)

[Nick1911]

I've seen some similar devices (production built) for charcoal smokers.  We're talking crazy levels of sophistication for what is really a very simple process...  :)

We're Americans.  We take grilling/smoking meat very seriously.

[AmbulanceDriver]

Oh, I'm not saying it's not worth it....  Just never realized the levels to which people take it.  :)

[Jim147]

My self and a couple of techs I used to work with designed a wood smoker using an electronic oven control and matching temp sensor. The plan was to have it open vents with a stepper motor and turn on a fan when the fire started to die down.

We never did finish it. Sitting by the smoker drinking beer, even when we started at dark o'thirty in the morning, allowed us to keep an eye on the temp.

I did build a small electric smoker a few years back. It uses a hot plate so it is on or off. A control set up like you did would be good for that. If I have to leave to run a no cool, I can leave it a going till I get home.

jim

[French G.]

I need to learn electronics badly. Say I want to build a tempering oven and have access to stainless steel for scrap price, can weld and have random items like hot water heater elements. How hard is it it to make an oven that tops out around 800 F?

[Jim147]

You going to run that oven in selfclean mode all the time?

When you have time look at this site for an into into electronics and what things do. http://101science.com/transistor.htm

I think with the group we have around here, most questions could be answered pretty quick.

jim

[Gowen]

Way back in the 70's my uncle used to smoke cheese.  He would put a block of jack and a block of cheddar in a pie tin and smoke them together.  We would go camping and sit around eating smoked cheese and crackers all night.

[RocketMan]

I need to learn electronics badly. Say I want to build a tempering oven and have access to stainless steel for scrap price, can weld and have random items like hot water heater elements. How hard is it it to make an oven that tops out around 800 F?

I'd think you could pick up a suitable oven on eBay.  You might have to change out or add a controller to do what you want to do, but that wouldn't be hard.  Lot's of temperature controllers available, and an inexpensive type 'k' thermocouple would work well in that application.

[sanglant]

if that's going in a house i would suggest upgrading the insulation. i bet this stuff would be interesting. mainly for temperature control in the house, but also to keep from charring the cabinets around the oven.

[RocketMan]

The first batch of jerky is in the smoker.  The temp is controlling nicely.  We'll see how it turns out.

I'm sure glad the autotune function on the controller worked.  It's been a lot of years since I had to manually tune PIDs on a furnace of any type.  Back in the day when I had to tune controllers on GaAs growing furnaces, it was more an art than science.  Of course, those were multizone furnaces running at 1280°C, and not a simple single-element electric smoker.