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1lb FB hopper roaster
I think I see some issues, scorching and tipping in the middle and a bunch of under roasted beans in the top section of the picture, they can't all be Quakers.

I want to add that when I download the picture and zoom in it does not look as bad as on the site, I do think you have some much darker beans and some much lighter. Some variation will always occur.

I definitely think the bean movement needs to be improved, sorry.
This might help.

Now this is more about a drum but just think of the bean movement, more air in this case.
Edited by HarryDog on 10/30/2023 11:24 PM
Bummer.... I've got some experimentation I'm going to try before building new hopper. Thanks for feedback!
nickr, if you are thinking of using a deflector I was thinking of using a cabinet stainless steel knob but my current chamber is too small. Use some threaded rod, put a couple of nuts on it so it can be moved up or down for different loads.

Just a quick item to see if it makes enough of a difference?
What is the purpose of the bean deflector?
It's one way to have the beans directed from the spray to the edge of the chamber so they can return back to the bean mass. Hopefully creating a faster bean rotation and keep them heating as evenly as possible.

So in the FB if you increases the air flow it sprays up cooling the beans and keeping them out of the hotter bean mass, you want to keep them moving but in the hot bean mass as much as possible.

This is a video demonstrating this from progen.
Figured, just making sure I understood the concept. I just purchased these

Edited by allenb on 11/02/2023 6:32 PM
Dollar store stainless steel bowls would work? Lots of sizes. Just a few taps from the inside in the bowl would give it a much rounder base.

Coffee Crafters talks about the conical hopper, some info might help if you want to make other changes.

Edited by HarryDog on 11/02/2023 3:05 PM
Tried a roast with higher airflow, 60% the whole way. This is a wet process Bali. Was able to keep within good roasting parameters, FC at 7:50, drop at 9:50 (435f). Not sure it improved much.
nickr attached the following image:

Edited by nickr on 11/16/2023 8:42 AM
If you watched the Coffee crafters video he talks about a more conical hopper to help with lofting the beans. This keeps the bean mass over the air flow. So he has a 1 7/8" inlet. The screen holes I used are 7/64 and biggest might be 1/8" if roasting smaller Peaberry beans.

If the evenness of the roast is still poor then if you have a smaller cylinder 1-1.5" smaller slide it into your roast chamber and see how the beans will loft, it should improve. The other change you can do is use a deeper funnel for your base giving you more of a conical funnel shape to your roast chamber.

I enjoyed my last order of Bali, just got some more in and will start roasting that again soon.
I did watch the video which I found very helpful but not I think I’m going to build air curtain type hopper next lol.
The screen I use has no holes, but is actually a spiral. I’m also considering going to a mesh screen
I also changed to a glass cylinder that’s is slightly smaller in diameter. Can really see what is going on now. The graph attached is from the video. I was running more loft to get better movement but did notice a dip in BT in the middle. youtube.com/short...npJYqpCBW1
nickr attached the following image:

Edited by allenb on 12/08/2023 11:47 AM
Meant to attach screen photo also
nickr attached the following image:
The video was to show the relationship of the funnel type design (Shape) on how much easier it is to control the bean flow. I do like the curtain chamber and think it might be a good option for a 1KG FB.

Interesting spiral plate, I would tape the outside 1-1.5 inch of that plate to concentrate the air more in the middle. Just as a flow test to see the change.

The bean movement is all over the place, beans are returning close to the middle all the way to the edge? Keeping the air more in the middle might help the bean flow on return. I would also lower the air for this size of bean load to help keep the beans in a tighter movement pattern if that makes sense.
I just posted another video on my YouTube with lower airflow. Looks much smoother, but still all over the place. The spiral screen in the roaster is cut down to just the center portion, my inlet is 1 3/8" OD.
I think that is a much better pattern!!! Making a drilled screen might be better but I think that is a good improvement.
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