This is a bit of fun for all you DIY Kiwis. Grant is a fitter / turner and after many years of popcorn roasting, he determined there just HAD to be a better way.
He researched the internet then built this roaster out of some pipe, an old vacuum cleaner engine and a blow torch. It's not quite as simple as it looks and took some experimentation - especially building up the interior of the pipe so that the beans rotated evenly - but it will roast up to a kg of coffee very quickly.
This was before bench top roasting machines like the Behmor were available for our convenience.
Enjoy!