If you are concerned about uneven roasting of beans the first thing to consider is the coffee you are roasting. Sometimes green beans are themselves very inconsistent, consisting of a wide range of bean sizes, ripeness at picking, and processing variations. Do not spend time trying to get inconsistent coffee to roast consistently.
However, if you know that your coffee is well graded and should roast consistently, but it is not, or if you are seeing a small number of obviously burnt beans in among otherwise well roasted coffee, your fan speed is most likely too low it can cause your coffee to roast inconsistently, you can adjust this by;for the coffee you are roasting. This could indicate a need for re-calibration, but it could equally well indicate an unusual coffee for which you need to make some adaptations.
In KL Studio, click on the ‘Fan profile curve’ tab, here you can make manual adjustments to the curve.
In the same tab, click on ‘Tools’, ‘Transform profile’, and in the second RPM block on the right you can enter a value to move the profile up, or a negative value to move it down.
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