HomeRoast Digest


Topic: turbo melt down (38 lines)
1) From: petzul
Today I preheated my Turbo Beast..
...and walked away.
When roasting it is a good idea not to get distracted.
Just keep an eye on things.
When I got back, the thermo couple read 540F.
Fine says I, a quicker ramp to 300F.
The glass is all covered with coffee deposit on the GG, so I could not 
see what was going on inside, and I thought it was weird that I got some 
first crack on my 588 Gr batch at only 370F.
When lots of cracking started at only 400F I removed the lid to see what 
was the matter.
At first glance it looked okay. The beans were sloshing, kinda, but then 
I noticed they were not really moving enough!
The stirring arm had come apart!
When it had cooled down enough (with the hair dryer) to dump everything 
I found some burned beans, some raw beans, and the arm of the main 
stirring rod had melted!
Scrap that batch :-(
Not sure what metal it is made of, but it melts below 600F.
What happened when I dumped in the beans and turned on the mixer is the 
arm bent backwards from along the radius to almost a tangent to the 
center hole. A nice sweeping curve, so then the ramp part I had made 
just detached. Interestingly, the HT silicon sealer holding everything 
together did not fail, but what it was glued to did. It deformed enough 
to come apart.
The motor and belt seem fine, and the mixing bowl chamber is not affected.
Right now I am in the process of rebuilding the stirring arm, and 
cutting a hole in the glass lid of the GG so I can add another heater.
PeterZ
Another lovely roasting day, here in LHC, AZ.


HomeRoast Digest