Home Coffee Roasting with an RK Drum, part 5
Digital Thermometer & Thermocouple

Roasting with an RK Drum, part 5
Digital Thermometer & Thermocouple

Temperature control is one of the important features of using a gas grill-based roaster, as it is for any type of roaster.

The gas grill, though, is especially susceptable to temperature variations because of wind. The large exposed shell can also cause you to have significant temperature differences, season to season, for any selected gas flow.

If you're roasting your own coffee, you are likely to be using "the good stuff," too -- not cheap green coffee but green coffee that costs significantly more per pound than the standard coffee brands.

I use two thermometers when I roast. I have a large New Braunfels Smoker analog dial thermometer mounted in the front of the grill (see my RK Drum #1 page).

I also use a digital thermometer with thermocouple to be able to monitor the temperature changes more quickly.

You can find the digital thermometer/thermocouple set at Sweet Maria's Home Coffee Roasting Supplies on their Home Roasting Accessories page.

In this first picture, you can see the left side of my grill, with the digital thermometer standing in a small wooden block (I used a dado blade to cut an angle slot in a piece of 2x4 for a stand). The thermocouple wire snakes around to the 1/4" brass tubing compression coupling.

I had this coupling fitting on hand. It makes a nice "stop" so that the wire can go through the copper tubing and the tubing won't fall into the roaster (see my RK Drum #1 page for the original -- which was a long piece of tubing stuck through the side).

The next picture shows the inside of the drum. Notice that the copper tubing simply sticks through the side of the grill. The compression fitting keeps it from falling in. The tubing is free to swivel with gravity.

The tubing is bent into an elongaged S shape. When the grill is closed, the end of the thermocouple is horizontal, level with the rotisserie shaft and about one inch to the front of the shaft.

The last picture is a closeup of the thermocouple mounting assembly (isn't that a nice word for this?). You can see the thermocouple wire sticking into the brass fitting and the thermocouple bead sticking out the end.

You might wonder why the thermocouple wiring is so dark — black and brown.

This is the same thermocouple that I was using in my Hottop coffee roaster.

Coffee Roasting |  2 |  Hottop |  2 |  Hottop Tips |  RK Drum |  2 |  3 |  4 |  5

Copyright © 2006 Terry A. Stockdale. All rights reserved.