mycuppa wrote:
Is it mounted on wood ? I know wood is a great thermal insulator and you are in the prototyping stage, but you may want to think about some safety pretty soon - flames and wood are not a good mix.
It is on timber at the moment, but just sitting there. I will be sitting it on a metal photocopier pedestal soon (metal) and I'll probably put some masonite under it as a thermal insulator. It's actually not "Mounted" on anything as such. It all just sits there, which makes it fairly portable. Out of the shot of the photos are two fire extinguishers within reach, just to be safe.
mycuppa wrote:
Does the gas burner/bottle have a regulator ?
Yep. Standard regulator. Also, before you ask, I have a CO detector mounted nearby based on your previous advice.
mycuppa wrote:
Speed of the drum is less important than what a whole bunch of people may think (this applies to drum method). Many years ago I thought it was important and run a whole series of controlled experiments. Result = did'nt matter. There is way too much written on the internet about the perceived benefits of drum speed controls and this only comes into play on very large roasters with contact volume ratio and significant inertia lag. Reality is ........purpose of drum rotation is agitation and so long as you have something close that gives you reasonable turnover of product you should be fine. Reason I write this is so you can focus on your airflow and other thermal characteristics first and don't worry about drum speed - you probably knew that already.
From what I've noticed, it doesn't seem to matter too much. I'm at about 60rpm at the moment, which is a bit quick, but seems to disperse the chaff well, but not break the beans (thus why the roast looks so even I think).
mycuppa wrote:
You may have already been told, but make sure you adjust your burner flame so you have a nice small blue needle and minimal/no large yellow flame.
Yep. CO poisoning isn't really my thing.
mycuppa wrote:
When designing your airflow system it only needs to be quite low pressure and of course you will need to direct the chaff and smoke somewhere.
As yet the airflow system is "whatever leaks out the lid area". I HAVE to do something about smoke and chaff though. I'm thinking a small chimney and a rearranging of my garage so it vents out a nearby window, and a vacuum for sucking chaff at the bottom. I'm impressed with a lot of the home style roasters that have minimal airflow (iRoast, KKTO), so while I'll focus on airflow soon, I'm thinking just a gentle breeze instead of a gusty wind. It's all just a start right now, but I've got the basic hard bit nutted out, so looking forward to taking it to the next level over christmas break. I'm trying to be a minimalistic as possible for both cost, and reproduction reasons.
