Diy home roaster question

[yenemy]

So I built a very hacky drum roaster for home use, and I'm running into an issue where my beans will hit first crack just fine, then they will stall and eventually burn before I ever hear a rolling first crack phase. I've encountered this with a wide variety of beans, mostly from South/Central America, washed or natural.

I know I have a ton of variables that I'm not providing, but generally in this situation would someone be roasting too hot/fast, or too cool/slow?

Thanks!

 

[Musicphan]

You don't list times so its hard to tell... are you sure your not hearing 2nd crack?

 

[yenemy]

For what is worth, I am using a 5x9 cage on essentially a diy rotisserie spit, in a 12" terracotta pot as an enclosure. My heat source is a Wagner 750 heat gun, with the duck bill attachment, blowing through a port cut in the side of the pot. The pot is covered during roasting so aside for one or two peeks in the middle to check for blonding, I'm going by sound and smell.

The last few rounds I've been purposely overloading the roaster to see what I can get away with; so using 500g of beans I am starting with a "medium" 800F temperature setting for 10-14 minutes to get it to a light blonde stage, then pushing the temperature up to high (1100F) for the final roast, which has been anywhere between 10 and 12 minutes (so 20-26 minutes total). With those settings I am hearing a first crack right around the 22 minute mark, depending on ambient temperature and the bean I'm using. My thermo setup isn't working yet, or I would have actual roaster temperatures for you, rather than just the heat gun setting, sorry.

I am pretty sure what I'm hearing is first crack; it is quite pronounced, like popcorn popping but sharper.