First, let me apologize to Marlyece. I blame my inadequate abilities to communicate succinctly. From you responses to my posts, I can see that you don't have a good grasp on my points. Please, for safety sake, pre-roll all your DP greens before your roast....small grid basket or not. That may very well help prevent a fire...or worse. I'm going to go on with my post. Because the following is based on my previous posts, you may want to skip them to avoid further confusion.
I've included a pic of the ~14gm of Harrar that went through the Behmor large grid screen. This is the sum total for ~2282gm of green coffee. This is about 0.6% dropped beans. As you can see, many of these beans are very small or broken. The current grid size of the Behmor basket Is .080". The new grid will measure .071" A spot check of the beans pictured here indicates that over 25% or at least 4.5gm are small enough to pass the .071" grid. That means that a 1lb roast will still drop about 1gm of beans with the small grid basket. In my mind that is significant enough to warrant concern. Joe B. seems to be under the impression that .071" is small enough to prevent bean drop. I don't think so. I doubt that the roaster could utilize a much smaller grid than .071" and operate properly. The thermal mass would increase significantly and the bean exposure to heat would be less. I believe that such change would require significant re-programming to be utile. That might not even work. This all becomes mute if one simply does a pre-roast 'dry roll' to drop undersized beans and fragments. Especially for DP, decaffe and robusta beans. In support of Joe B. , I feel that this machine is very well thought out and engineered. Personally, I still see no need of smaller grid baskets.
I did make one more very alarming discovery. It's potentially fire and even serious injury producing. I noticed a rather large quantity of fine dust among the dropped beans. The 5# of Harrar produced about 3gm of fine dust like material. Microscopic examination showed the material to be nearly all organic in origin. I surmise that most would be berry, chaff and bean dust. I wondered about flash-over volatility. I tested the powder like one would test lycopodium powder, over an open candle flame. The powder was nearly as volatile as lycopodium powder. In other words nearly explosive. I would worry that this dust could, under a rare circumstance, concentrate near the quartz lamps and flash-over. This would be similar to a mini coal mine dust explosion. The resultant explosion could blow the door open thereby releasing flame and heat. I have heard of similar mishaps among commercial roasters. Again, this scenario could be easily reduced or eliminated by simply pre-rolling the greens and vacuuming the resultant dust before the actual roast. For me, I will never roast a DP bean without doing this first.....with any size grid basket.
Phil
