I decided to jump an upgrade my current heat gun: Master Proheat LCD ph-1400



This one has digital controls for both airflow and heat. Once the dryphase is finished, I turn this puppy on and it is like launching a rocket to the moon. You can control acceleration, speed, etc, which adds much more speed control to profiles as well as batch capacity.



It comes with two reducing tips, one big and one small. If you buy one, get the small one. The big one fits in the Q3 but the airflow is too big even at the smallest setting. The smallest restricts the airflow. A setting of 2 is ~ what I was using in my previous heatgun. A setting of ~700F is a good start (temp will drop with distance from tip).

You would also need a 1/8" X 3/4" x36" piece of aluminum from HomeDepot. You need to bend it at the edge of a table (round edge). Then cut the length.



The benefits are huge in terms of flavor. I know that it breaks the idea of a "perfect roaster" design but it gives the extra punch. Basically you end up with the most controllable roaster.

For best results, get the thermocouple adapters from Eric and a two channel thermocouple logger (to plot the profile in a computer). Once you try the results, there is no way back

Cheers

Yes, you can preheat the incoming air but with very minor results. I spent much time doing that last winter (when preheating the air was important) before I jumped in to the heat gun method.

The heat gun method is better, no fuss, easier, and with much more control. It is like having two different roasting methods but both are used. I use the heat gun only in the second phase (ie. from 300F to ~ 1C).

Cheers

Are you running that heat gun off the same circuit as the M3? If you are, then it ought to be possible to build an M3 just with beefier heating elements and maintain a "perfect roaster" design....
Roy

Hi Rmongiovi,

I use a different power feed for the Q3 and for the heat gun.

The problem is not that the Q3 is weak. A more powerful heater would not do anything . If you use more power, the drum heats too much and the beans scorch (too high drum temperature). What was needed was a way to run the drum colder but at the same time deliver more heat to the beans. The only way to do this is to use air convection. You can still do fine roasts in the Q3 without a heat gun, but you have to watch the batch weight, the ambient temp, and it responds slower in the profile. This is more an enhancement than a fix.

Cheers

Arpi
What batch size are you running with the HG added?
farm

I've been using around 300 grams. It can do more but that is ~ the the volume limit of my small vacuvin canisters.

This is a picture of the drum with two cups of green beans (~300 grams depending on bean density). Don't remember for sure the volume, but I think it was two cups.



Maybe I could fit 3 cups (450 grams), not sure. I think the weight limitation with a HG added would be the volume.

Cheers

Blowing air into the trier hole will reduce the airflow over the M3 heater elements. Be careful to not burn them out by overheating them.

Hi Márcio,

I have only preheated the air with the heat exchanger mod. Never tried to put a controlled heat gun in the intake hole.

JohnM,

Good point. I am lucky that I have PIDed heating elements, but maybe someone without a PID could burn them. I think that the fan of the Q3 would need to run higher than the fan of the heat gun.

Cheers