I finished my custom food mill design after few days of squeezing my brain out, reading built-in program help and watching lots of video tutorials. The design is so simple but it took me few days to finish it. I am hoping the cost of fabrication is within my cash reach. I also hoping that my next design would be easier.
Where is the design? I am only posting image of finished product if it materialized. My friend also need it so if he managed fabricating it first, then image of his comes first.
My next project is a coffee roaster, not because I am planning of roasting coffee. I am going to use it for cocoa roasting instead. There are not much info for building cocoa roaster but coffee roaster have. The same construction could be used for roasting cacao but their control settings are specifically built for coffee.
Cacao need initial high temperature for easy removal of shell, then a lower temperature to let temperature properly penetrate the inner part of the bean. It is totally different from coffee roasting, where high temperature is maintained throughout the roasting process. Coffee should be roasted within 15 minutes or shorter while cacao needs more than one hour.
If gas flame is used as heat source, it should not directly touch the roasting drum. It will cause metal chipping and shorten the roaster service life. There must be some kind of heat exchangers, air blower or spacer to avoid it.
Charcoal type roaster tend to impart flavor to coffee. This reminds me of oak barrel imparting flavors to wines. Temperature control is very erratic.
Temperature is such a hard parameter to control. Even with the fully computerized systems.
Infrared type roasters are rare. However, it seems to give the most desirable roast because of the more accurate temperature control. I am eying for this but wary of high electricity consumption.