I've been roasting on a Diedrich IR-7N for the past couple of weeks and am having trouble creating a good profile....I've been roasting an Ethiopian Kaffa Forest from Atlas Coffee Importers in Seattle. 

I'm roasting at about 5,300 feet elevation in dry colorado air.

Started off following manufacturers recommendations....Here's a breakdown of my 1st couple 5lb roasts

#1 

Gas on WC meter: 2

Charge Temp: 422

Drop Temp: 225 (forgot to log)

Air 50/50 280degrees: 2:27mins

1st crack (switch to roasting thru Drum):  390  (forgot to write time as I knew it happened way too quick!)

Roast finished: 425 in 7 minutes!!  

#2

Gas on WC meter: 1.25

Charge Temp: 402

Drop Temp: 203 @ 1:20mins

Air 50/50 280degrees: 3:50mins

1st crack (switch to roasting thru Drum):  385 @ 9:40mins

RAMPED UP gas to 1.5 @ 12:40 mins since it wasn't climbing

Roast finished: 422 in at 16:09 which is an insanely long roast development stage. 

#3

Gas on WC meter: 1.5

Charge Temp: 418

Drop Temp: 213 @ 1:20min

Air 50/50 280degrees: 3:12mins

1st crack (switch to roasting thru Drum):  390 @ 7:25

Roast finished: 423 @ 10:25mins  

#4

Gas on WC meter: 1.4ish

Charge Temp: 420

Drop Temp: 211 @ 1:27min

Air 50/50 280degrees: 3:20mins

1st crack (switch to roasting thru Drum):  390 @ 7:43 

Roast finished: 422 @ 11:00mins

#5

Gas on WC meter: 1.4ish

Charge Temp: 383 (was trying to slow roast down, this way....good idea??)

Drop Temp: 209 @ 1:18min

Air 50/50 280degrees: 3:13mins

GAS LOWERED to 1.25 @ 3:33mins

1st crack (switch to roasting thru Drum):  383 @ 10:45mins

ROASTING seem to stall at 383 so I brought gas up to 1.5 @ 11:15mins then 3 @ 12mins and then to full bore which is a 6 @ 12:30mins

 

Roast finished: 423 @ 15:25mins

#6

 Gas on WC meter: 1.4ish

Charge Temp: 377 (was trying to slow roast down, this way....good idea??)

Drop Temp: 195 @ 1:30min

Air 50/50 280degrees: 4:07mins

1st crack (LEFT AIRFLOW AT 50/50 to try for a steady climb???):  383 @ 9:35mins 

Roast finished: 422 @ 13:10mins

I'm having a hard time finding out the ideal way to create my initial profile.....seemed to get the steadiest temp climb leaving it at 50/50 from 280degrees on?? What sort of effect does this have on the beans?? 

Based on my numbers, what variable should I try changing 1st?  At what roast stages should I be increasing the gas or decreasing?? From my very little experience, it doesn't seem like I'm gonna be to keep the gas steady throughout the roast??

Thanks in advance for any suggestions!  I'm gonna be roasting again on Saturday and would love to have some new things to try!

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