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· 07/04/2020 10:27 AM
Happy 4th of July! jazzyhands

· 06/24/2020 7:58 AM
@Mark McCornack, Please post your question in the forum.

Mark McCornack
· 06/15/2020 9:28 PM
Hi! Looking for a legacy inlet temp sensor on 13 yr old Gene Cafe. It seems they've changed it and now you need new mother board and new sensor. Any ideas where I can find compatibile old one? Mark

· 06/09/2020 6:39 PM
Wich thermometers Can i buy for my roasting machine compatible with usb or macbook?

· 06/05/2020 5:38 PM
peveleth, It is better if you start a post in the forum with your question. These shouts go away in time.

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Dereks 1-2Kg drum roaster build
I can't see why not, and it really doesn't look like that much effort.
I wish I would have included a removable baffle in my drum roaster. One bean may be better with it in while another may be better with it out.
All you need in life is ignorance and confidence, and then success is sure. Mark Twain
Looking forward to see the final one, looks very promising
Thread had to be parked for a time. Things are ongoing now albeit at a slower rate.

The process of converting the 3D to 2D drawings to get steels cut and various other parts fabricated has required to me reconsider a few things - normalizing some of the dimensions, aligning various holes for sake of simplicity etc.
I have also updated the 3D with other ideas I've had and it's looking better. I'll share the 2D files at some point once more complete.

I have a 20K BTU burner. A UK company came up with a bar burner with the best dimensions for my unit and were able to modify just a little as well to increase the flame proximity to the rear plate.
dmccallum attached the following images:
2d_scrape_2.jpg 2d_scrape_1.jpg

Edited by dmccallum on 07/18/2016 8:02 AM
And a photo of my burner..
dmccallum attached the following image:
Can you tell us about the burner? Where'd it come from and what did it cost? BTU output?

I love everything about this build, great design and 3D computer design work! Keep it coming!

BTW, I plan to steal as many of your ideas as I can!! Grin
Clever Coffee Dripper
Grinder: Macap M4
Roaster: Nearly complete drum roaster shown on this forum
I got the burner from this crowd in the UK,

Its 10-20K BTU although as I've asked them to TIG a piece across the first few holes it'll be a little less. The base item is about £50 and I think I paid about £20 more for the mod.

This particular burner just fit my cabinet better than the Polidor models I'd identified.
I love the quality and the price seems very reasonable! What's next on the agenda?
Clever Coffee Dripper
Grinder: Macap M4
Roaster: Nearly complete drum roaster shown on this forum
Cyclone Question:
One thing that has occurred to me is the direction of the vortex in the cyclone and should I be concerned about northern -vs- southern hemisphere coriolis effect. I suspect not, the force of the motor will overcome this although I've also seen comment that the vortex should travel in the same direction as your blowers impeller so that the motor does not have to work against it. Again though Bill Pentze suggests this is more of a problem once you go over 2HP, which I am nowhere near with the blower I'm intending to use:

So I suspect I can ignore these issues, but can anyone share some insight here or describe the config of the cyclones they're using?
Edited by JackH on 08/17/2016 5:41 AM
It will be important to get the cyclone right, in my experience if you're not getting 100% separation and have a squirrel cage fan "pulling" air through your setup it will chaff will clog it very quickly, they often cant handle the heat as well............. my search for a suitable fan started with blowers made for "pellet fires" or combustion fans, they have a radial blower which doesn't clog up... r.e cyclones the ratios are very important.

Google this "Performance Characteristics of Cyclones in Cotton–Gin Dust Removal" its a very good research paper to start expanding your cyclone knowledge with a product more "chaff" like what were dealing with (stuff around wood chips aren't really relevant in my opinion) my latest system uses a modified 1d3d arrangement and works perfectly 100% separation.....
Also Google "thien separator" if you want another angle to take........ I went the cyclone way my self given the los mass of the average chaff particle....... but didn't built one to try it out... :-)
Thanks very much Broeker.

That paper is one of the better ones I've seen and I wasn't aware of the Thien approach - might be worth experimenting with, fabrication is probably easier. In fact you could possibly incorporate the concept into a barrel cyclone depending on the dimensions.

For the most part I have duplicated the design/dimensions of the San Fransican SF-1s cyclone and made it a little taller (a chap called Moshe from Seattle was kind enough to take his SF-1 cyclone apart and give me very detailed measurements and photos). So I have 'assumed' SFs design is solid and will work for my purposes - might be wise, it might not. I've also assumed the high-temp squirrel cage blower I intend to use will not suffer unduly.

I'll digest the paper some more, hopefully I'm good to go as I am.
dmccallum attached the following image:
Ah cool, you are fortunate to have a good working start point, It gets very scientific very fast the cyclone game. All I can add is my first effort worked ok (like 1d2d with a very basic tangentel circular inlet) with some chaff 1-2% getting through to eventually block the squirrel cage fan, but my new ones ( the 1d3d proportion with the rectangular inlet that slowly over 180 deg merges into the body) are 100%. But the taller more efficient cyclones do require the air flow to work properly....

Umm don't over look making the collection volume large enough, if you make it to small when it fills up to a certain point the chaff will get re-entrained and get sucked out of the cyclone were it isn't wanted....

Try to make things were you can clean every surface..... Because internal crud will rob your fans power and reduce the performance of the whole deal...
Another thought I've had is the throughput of the two 1 3/4" pipes I've got going to the cooling tray and whether they're enough.

The area of the 3" inlet pipe is 4,200mm2 and the combined area of the two 1 3/4" pipes is 2,666mm2. Even if I squeaked another pipe in its only going to 3,999mm2.

If I put box section in I can equal or exceed the 3" inlet pipe.

I rather prefer the asthetic of the pipes over box, but functionality comes first and don't want to build this to find the pipes are a choke point. The cooling tray has a much larger area around 45,000mm2+ and so I want to ensure I get adequate flow.

Anyone have any thoughts ?
dmccallum attached the following images:
cooling_tray_draw_capacity_options2.jpg cooling_tray_draw_capacity_options.jpg
I have been minded to do some further research and testing on how well my proposed cyclone would work, so I’ve mocked up a model of my design and this is what we’ve got so far.

I’ve kept it simple for the first round of testing with no additional cones, air ramps or Thien baffles.
I’m using my Dyson vacuum and figure it has roughly the same CFM as the blower I plan to use. It has quite a bit more power though, and you can see what it did to my model within 2 seconds of having absent-mindedly put my hand over the inlet to test for leaks.

To test initially I’m using about 600ml of finely cut up tissue wrapping paper. This is a pretty close approximation of chaff although I will have to find a source and test with this also.

Pleased with first pass and remarkably only about 10 pieces of tissue made it through to the vac. Noted however that this got worse on repeated test and wonder if static-electricity is playing a part.
dmccallum attached the following images:
initial_components_1.jpg initial_test_setup_1.jpg initial_result_1_1.jpg initial_result_3.jpg initial_top_view_1.jpg

Edited by dmccallum on 09/28/2016 5:39 AM
Next up I put in what approximates a Thien-baffle about 120mm from the bottom, and I get a repeat of about 10 particles making it through to the vacuum.
dmccallum attached the following images:
thien_baffle_120_result.jpg thien_baffle_120_setup_top_view.jpg thien_baffle_120_setup.jpg
Then I move the Thien-baffle up to 160mm from the bottom, and with 3 complete test sequences I get 100% separation on each run – no bits of tissue pass to the vacuum.
I’m amazed, and possibly getting ahead of myself. There’s a roaster not far from me who I’ll look to for a source of real chaff.
dmccallum attached the following images:
thien_baffle_160_result_1-3.jpg thien_baffle_160_setup.jpg
Dyson damage
dmccallum attached the following images:
blown2.jpg blown1.jpg
A South London roaster kindly provided me with the contents of his (much larger) cyclone from the mornings roasting. Obliged me also with a tour of his operation where he uses a 1950s Vittoria 30Kg roaster.

So first test with the same Thien up-ended conical baffle at 160mm from the bottom and a 600ml jug of chaff, fed slowly over a couple of min and I'm amazed that nothing got through to the Dyson at all. Even the fine dust all went to the bottom of the cylinder where it mainly adhered itself to the sides.

I'll do a flat Thien baffle over the next day or two and see how that goes - would be easier to fabricate. It's hard to imagine it's worth going to the trouble of doing a regular conical cyclone at this stage however there are a few variables which I haven't tested against yet, like lower air flow rates etc - up to this point I'm testing with the full Dyson suction.

Does anyone have an idea as to how many Kg of beans you'd have to roast to produce 600ml of chaff?
dmccallum attached the following images:
thien_baffle-cone_160_result_wth_chaff_4.jpg thien_baffle-cone_160_result_wth_chaff_3.jpg thien_baffle-cone_160_result_wth_chaff_2.jpg thien_baffle-cone_160_result_wth_chaff_1.jpg chaff_from_s-london_roaster.jpg

Edited by dmccallum on 10/06/2016 7:25 AM
Wow, you've taken the R&D on cyclones for roasting to the next level! This will be great information for others here to use as a jump start to get their own cyclone fabricated. It would be interesting to see how much of a reduction in complexity you could go and still pull all of the chaff and most of the fines out.

I'm not sure where, if anywhere one would go to find out the answer to your question on chaff volume per kg. You might have to offer a free chaff removal from the Vitorria in return for getting chaff quantity data.

1/2 lb and 1 lb drum, Siemens Sirocco fluidbed, presspot, chemex, cajun biggin brewer from the backwoods of Louisiana
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