The Ultimate Home Coffee Roaster

One of the best parts of my job is learning how people like to experiment with coffee at home. I’m constantly talking to fellow coffee geeks about the latest brewing technique, the newest brewing apparatus or their favorite Chemex / french press / Aeropress / espresso recipe.

But despite all of the geekery in brewing coffee, it seems that one loves to experiment at home more than home coffee roasters. For these people, it’s about so much more than a good cup of coffee. It’s about tweaking their hardware to get the best coffee possible often times with equipment they have around their house and their own skill set.

Meet My Friend John

My friend John Clulow personifies this like few others. John has been buying roasted coffee from us for a while but just recently, he asked us if we could supply him with green, unroasted coffee. We’ve been selling green coffee to home roasters for quite a while now so that was no problem. John mentioned that he’s been working on a home coffee roaster setup based around a hot air popcorn popper.

Naturally, I was excited about what he was doing and asked him to come by and show me his setup. Wow! It was absolutely amazing!

Here’s a short video showing off an early version of John’s setup. If you’d like to learn more about his passive chaff collector keep reading below.

Home Roasting in a Popcorn Popper

If you take some time to look around the interenet, you can find no shortage of people roasting in popcorn poppers. There are some limitations to this method, however.

Number one, you have very little control over the heat and airflow – two essential elements to roasting quality.

The second problem with home roasting is that it generates a lot of smoke and chaff that floats all around the room – making it very difficult to roast coffee while you’re inside. Chaff is a paper like substance that coats the outside of the unroasted coffee bean. It can make quite the mess.

Again – doing some research – you can see how various home roasters have overcome the problems with control of heat and airflow by putting dimmer switches in the electrical circuit. Many of these guys run into issues with overpowering and blowing out their popcorn popper or overheating and burning out the dimmer switch. Without an in-depth knowledge of resistance, electricity, Ohm’s law and how it’s being used, you can run into some difficulties very quickly.

As for the chaff problem, there are a couple of solutions to capture chaff floating around the interwebs, but nothing that’s really caught on.

Experimenting, testing and figuring out the problem is, without a doubt, where my friend John shines. With a somewhat technical background (he was a chemist by trade before he retired), John has the tools and the knowledge and, being retired, the time to experiment and perfect these kinds of problems.

With that said – I present to you – JC’s Home Roaster (my name – not his)……

Chicago John’s Home Roasting Setup









If you’re not a home coffee roasting fan, some of this might pass you by. But if you have ever tried roasting coffee in a popcorn popper at home, this should get you really, REALLY excited. John has created an absolutely beautiful setup using his own know-how and mostly things he found at home or purchased very inexpensively.

Some of the absolutely AMAZING features of John’s setup:

John is able to control both the heat and the air flow of the popper separately

Using a simple thermocouple, he’s able to tell exactly what the temperature of the beans are

In the current incarnation of the setup, he has everything very nicely enclosed in an easy to transport case. The setup you see here is very compact and easy to move. In the video below, you can see how much bigger his setup is and harder to handle!

But Wait! There’s More – a Passive Chaff Collector!

But beyond all of that – the most amazing part of this whole setup is that John has created a Passive Chaff Collector out of a tin can and a copper sponge that does such a fantastic job collecting chaff and smoke that you can run this in your kitchen without any concern for making a mess at all.

This is HUGE! I’ve searched around the internet and haven’t found ANYONE who has put their know-how to work to build a chaff collector for home roasting. John was kind enough to come by our shop and roast a few batches and, let me tell you what, they came out fantastic!

John is posting about his new setup over on the home roaster’s forum where you can find him as “Chicago John”. We also uploaded the video of John when he came by the shop to show off his setup. Keep in mind, the setup in the video is an early version of his system. The photos at the top of this article are the lastest version of the setup. At least, they’re the latest I have – he’s probably upgrded it 4 times since he stopped by! You can get details about the passive chaff collector over on the home roaster’s forum as well if you’re interested in building one yourself.

Roast Your Own at Home?

In the meantime, if you’re roasting at home, keep in mind that we do sell our coffee unroasted as well! Any of our coffees can be purchased green by selecting “Green – unroasted” under the “Grind” pop-up menu. Most of our green coffee is 50% off of the roasted coffee prices.

If you’re a home roaster, share a little bit about your roasting setup in the comments below!