Latest Posts

  1. Video: A Cooler Way to Cool Your Behmor Roast

    Video: A Cooler Way to Cool Your Behmor Roast

    Cool your coffee faster by removing the drum.

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  2. Aillio Bullet R1 Support

    Aillio Bullet R1 Support

    Need a little help with your Bullet R1? We are here for you.

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  3. Intro to Home Roasting Class

    Intro to Home Roasting Class

    Sign up for this roasting basics class. It's going to be a lot of fun.

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  4. Sweet Maria's Featured on The Coffee Podcast

    Sweet Maria's Featured on The Coffee Podcast

    Listen in and share with a friend that needs a little motivation getting started with roasting on their own.

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  5. Hot Rod Home Coffee Roasters: The Spirit of Invention

    Hot Rod Home Coffee Roasters: The Spirit of Invention

    For some people who roast their own coffee, off-the-shelf home coffee roasting appliances don't cut it.

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  6. Air Popper Modifications -Adding a Thermometer

    Air Popper Modifications -Adding a Thermometer

    A thermometer can help you establish a more consistent roasting routine. Adding a thermometer to your air popper measures the temperature of the forced air heat flow after it has passed through the beans.

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  7. Gas Oven Roasting Method

    Gas Oven Roasting Method

    What You Need: A gas oven. A perforated pan, a vegetable steamer, or a stainless steel wire mesh collander.

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  8. How to make a Thermometer Clip

    How to make a Thermometer Clip

    Do you really need a thermometer clip? Well, not really, but if the dial face is moving around while you are cranking, it makes it hard to read.

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  9. Air Popper Modifications -Timing Roasts

    Air Popper Modifications -Timing Roasts

    When I started roasting with an air popper, I found that timing the roasts was difficult.

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  10. Another Home Roaster Takes the Leap

    Another Home Roaster Takes the Leap

    Sweet Maria's customer jumps into his own coffee business

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  11. Product Guide: Drum Roasters

    Product Guide: Drum Roasters

    Miniature versions of those commercial roasters you always fantasize about using.

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  12. Product Guide: Air Roasters

    Product Guide: Air Roasters

    Air roasters are put in the same category because of the hot air thing but they are all different. There's at least one here that fits your needs.

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Building a Drum Home Coffee Roaster

Building a Drum Home Coffee Roaster
So you are going to build your own drum coffee roaster? You're nuts, but you already know that... and in fact a drum roaster is a very simple machine. Hey, if this guy on the right can do it, why can't you?

Also see our pictures of the Jabez Burns Sample Roaster

Perforated Sheet Metals Used in Home Coffee Roasters

Here's some information to those interested in building their own home coffee roasters, especially drum type roasters to be installed in gas Barbeque grills, what hole-sizes and patterns are used in the currently available coffee roasting appliances. Here are some images, and all should be at the same scale, although they are not "actual size":

1. The Alpenrost Drum is unique among these samples: it is the only one desiged to allow chaff to fall through it while roasting! Notice the percent of open space to metal ... this is highly perforated. The holes measure just a hair over 3/16 inch. It corresponds somewhat to McNichols 3/16", 1/4" staggered centers, 18 holes PSI, 50% open area (although it looks even more open than this, more like samples with 60-65% open area)

2. The bottom of the Hearthware Precision Roast Chamber has 2 hole sizes. The smaller hole is 5/32 " and the larger is 3/16, same as the Alpenrost. This is a little suprising since the function of of this roast chamber is not to allow chaff to pass down through the roast chamber and fall down into the base. But with such a positive air flow upward, this is not much of a risk.

3. This is the ring from the interior of a well-used Hearthware Precision Chaff Collector. This hols size and pattern is identical to the Zach & Dani's coffee roaster's roast chamber bottom, but I couldn't get a good photo of that. The function here would be to hold back chaff, but allow air flow. It is approximately 1/16" holes and corresponds to McNichols 1/16", 7/64" staggered centers, 98 holes PSI, 30% open area

4. This is an image of the Coffee Kinetics 1 Lb roaster's roast chamber bottom. This roast chamber is like any of the smaller air roaster chambers (Freshroast, etc) in that a strong air flow comes up from the base ... so the function is to hold the coffee and resist letting chaff drop down (although air flow prevents this too). These are 1/8" holes and corresponds to McNichols 1/8", 3/16" staggered centers, 33 holes PSI, 40% open area

5. This is the Freshroast roast chamber bottom, and they appear to be 5/32" holes with a much greater open area than the Coffee Kinetics (But the CK roast chamber diameter is about 8-9" compared to about 3" on the tiny Freshroast). This material corresponds with McNichols 5/32", 3/16" staggered centers, 33 holes PSI, 63% open area

6. This is not perforated metal, it is a screen, and its from the top of the coffee kinetics. All manufacturers are using screen for places where they want air to pass, but all chaff to be trapped. Freshroast Plus has the coarsest screen, HWP is very fine, and the Zach & Dani's, in the top piece, has an extremely fine screen.

I hope this helps a bit! Happy roaster building, and remember to visit the best BBQ roaster construction sites:

  • is a great sitecreated by Ed Needham, with detailed articles on the construction of a rotisserrie drum roaster, and some neat articles about Maui Moka, Kopi Luwak, Etc.
  • Jim Gundlach has a great page with details on his home-built barbaque rottesserie roaster.The drum construction uses perforated sheet with standard heat duct for end caps. Check it out at

-Tom 2/14/03