I just completed my 5# grill roaster about a week ago. Done about 20#'s in it now (sold a bit under 19 of them, the rest was for my personal usage). Total spent to build it was about $750. Bean cooling system to go with it was about $100.
I had my drum custom made by a local welding shop. I supplied the materials and design and they put it together to my specs. I could have bought a premade drum online for less than it cost me to make, but I wanted the drum to be functional for me, not what someone else had designed. (Drum itself totaled $350)
Building this was really fairly simple and there are lots of others online who can give advice if you get stuck on it.
Jim S. is right about needing a five pound drum for that level of output. Just think about trying to roast 100# at a half pound per roast. If you don't have a higher capacity you will be roasting endlessly, and making very little for the time you spend.
A bit of advice I can give you though aside from the roaster is look for bean sources online that DO NOT charge for shipping once a certain level of money or #'s of coffee has been reached. Paying for shipping will cut a good deal out of your profits (especially if you are getting multiple 50# shipments a week.)
It is also a good idea to check out
http://www.homeroasters.org. There are more than a few people on that board that are running these micro coffee roasteries that can help you increase your options.
Lynn G.
LMWDP # 110
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