Drilling a hole for a probe (or thermowell).

[Smorker]

I have a Johnson 419a temp controller that recently came off of my fermentation freezer. I'd like to use it as a digital controller for my OBS. My thought for now is to punch a hole through the back of the cabinet and insert the probe (or a thermowell) through the back and use RTV or some other sealant to hold it on place. Comments or thoughts?

[GusRobin]

Use a food grade sealant. I have put holes thru the back with no problem. I would recommend that you take the back off or at least enough so that you can make sure you don't drill through a wire. But why not just dangle it so you have the flexibility to put it at different heights?

[mikecorn.1]

Perfect info from Gus. :)


Sent from my iPhone 5 using Tapatalk

[Smorker]

But why not just dangle it so you have the flexibility to put it at different heights?

I've lost several probes due to condensation wicking down the braid and screwing up the thermocouple. That's why I was thinking of using a thermowell. I could install a couple at different heights.

[GusRobin]

just seal the probe with food grade sealant

[Habanero Smoker]

What most members are using as a sealant is Permatex high-temp red RTV silicone. It is food grade for indirect food contact. I easily find it in auto supply stores, many find it in Wal-Mart.

You can also run your probes through the door.

[SmokinSignals]

I took the back off my smoker and drilled a hole right next to the existing bradley high temp switch.  This area was perfect for the thermocouple because the area around the high temp switch will be void of insulation.  My smoker is the DBS but should be very similar.  The metal is very thin so be extra careful to use a sharp drill bit and have someone back the hole you are drilling with a block of wood.

[Smorker]

Thanks all. We should getting some good weather soon, I'll pull the smoker out of it's shed and install the probe.

[paulsnapp]

I bought the Auber dual probe PID with the cabinet mounted probe option.  For most of what I do, this works out just fine and don't have wires dangling everywhere.  I have two other Auber probes for probe position #2.  One is the dangling one and the other is the food probe.  I can either dangle a second probe or insert a probe into the meat for internal temp measuring.  Everybody has their favorite but this is my setup.  As others are telling you, when you drill a hole it will tear since it is so thin.  I have drilled many holes with my mods for the permanent mounted probe, the second heating element and the fan kit.  What I do is begin with drilling a small hole which tears.  Then I use my Dremel tool with a bit for grinding stainless steel.  This opens the hole very quickly and very smoothly.  Good luck!

[GusRobin]

I use a step bit and haven't had any tearing.

[pikeman_95]

Gus is right. A step bit is one of the safest ways to get a hole with out tearing anything up. As for a thermowell they will slow down the temperature transmission. I would consider rubbing some of the high temp silicone into the probe end where the wire enters to seal it up. If it is a braided sheath make sure that you rub it into the braid well to seal it up. I have dipped mine under water accidentally and not had any failures after that.