Sheet Metal Mods and Roast Levels…
While there are several obvious things that you can do to help your bottom line when you are roasting for your customers such as buying bags and labels at good prices, and of course buying coffee at a great price, there other things that you may not have considered.
Don’t underestimate the importance of the sheet metal mods. These can dramatically reduce the consumption of propane or natural gas by anywhere from 1/2 to 2/3 by doing the mods. Most grills have quite a bit of open space
particularly at the rear of the grill which can be largely sealed off to hold your heat inside of the grill. The sheet metal mods section of the assembly guide details how to do this. Keep in mind you won’t want to cap it all off in its entirety as your do want to allow some venting of smoke and oils from your roast. In my personal experience and reports from other RK users, your burner knobs can be reduced to as low as 1/3 during the middle of the roast. If you have a particularly powerful grill, you may want to seal up less of the rear as it may prevent you from getting down to a low temperature for roasting lower volumes (Say 450F). When you’re doing the mod however, always start with more blockage than less as you can always cut off more sheet metal if you find it is getting too hot.
Now I must say that you do indeed need to be careful as installing the sheet metal mods may allow your grill to retain far more heat than what the manufacturer had originally planned for. While, I don’t believe your grill will melt, it is more likely to have a fire either from the extra heat the grill produces, or from a runaway coffee roast that eventually will ignite. We did actually have a RK user who’s system got away from him recently causing a melting of wiring and other components. One of the beautiful things about the RK setup, is that it is completely modular and can be replaced component for component if necessary.
Another thing that will help your bottom line is making attempts to keep your roasts between Full City and Full City+. Even going 20 or 30 seconds into 2nd crack can cause so much more water to be removed from your coffee that it will require 1/4 to 1/3 more physical coffee to make up your 12OZ or your 16OZ quota in every bag. Going beyond this into French and Vienna will cause even more weight loss via evaporation and thus more green coffee removed from your precious stash to complete your order. If you have never paid attention, take a look next time at how much coffee you put in one bag of full city vs. one bag of darker roast. If coffee is $3 a pound at it’s best price (at the time of this posting) then you can think of that as nearly $1/lb you are keeping in your pocket for every pound you sell.
To summarize, by performing the sheet metal mods, you can get 2/3’s more roasts out of every tank of propane, and by keeping your roast times low, you will save that much more green coffee.
I want to put special emphasis on “Keeping your roast times low” as I hear some stories of people roasting 2LB for 20-25 minutes. This extended roast time will also cause greater water evaporation and more green coffee volume required to complete your orders. You will certainly have that customer who wants darker coffee, or your particular bean might roast better darker, or you might need it darker for your espresso blend. In those cases, by all means roast it to where you need it. I think at the end of the day however, wherever possible, when your customer “Only wants great coffee”… Keep your roasts right at the edge of 2ns crack. and at the end of the year your bottom line could be padded by an additional 1/4 to 1/3 more revenue. -Shane