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Fluid Bed Roaster Build - bye bye Heat Gun and Flour Sifter
jbrux4

Quote

CK wrote:[/url]

An image of the internal layout when installed.

Here's an image of how the transparent roaster is wired on 3 circuits. No issues whatsoever.


Thanks CK. This provides some clarity for me. There is an additional cost for the additional SSR, but the way this is going, I might as well.

BTW - your build is so clean and inspiring.
R/
Jared
 
jbrux4
IN-LINE HEATING ELEMENTS QUESTION:

Since I have decided to do the heating elements in parallel, each with their own SSR, I am now concerned with mounting the elements in-line in the heating tube.

I do have 12gauge high temp MG electrical power wire with mica sleeving and fiberglass overbraid to connect the elements from inside the tube to the outside of the tube. However, if the elements are in line, will the top element's terminals have too much exposure to heat? The elements are HAS-043K, 1750W, 14.5A, 110V. Both terminals for the element are located at the bottom of the element. As I understand it, the intent for the element in a heat gun is to have the terminals at the "cool" end of the element where the air flows past it taking the heat away from the terminals. With an element in line, essentially on top of the bottom element, those terminals will get a lot more heat. Am I risking terminal failure or melting if I do these in line? Any other risks here?

Pic of element: https://www.amazo...B015E6CTRG
Edited by jbrux4 on 11/04/2019 1:34 PM
R/
Jared
 
greencardigan
My opinion is that it will be easier to have the elements AND airflow in parallel. That's how I went with my builds.
 
jbrux4

Quote

greencardigan wrote:

My opinion is that it will be easier to have the elements AND airflow in parallel. That's how I went with my builds.


Thanks for your very qualified opinion.

I need the blower to get here before I see the options for a manifold or not. It is on the way.

I don't have a 3D printer to create a custom manifold though.

It is an option that I will definitely consider. But, do you think the in-line method is dangerous for the top element?
R/
Jared
 
greencardigan
I'm sure an in-line solution could be designed to work safely, I've just never seen it done or tried it myself.

I think the terminals on the element you linked to would be fine. It would be the wires connecting to them and any insulation on the wires. Somehow you'd have to keep the two wires electrically isolated and get them out through the element chamber which would presumably be made of metal.
 
jbrux4
I think I have a solution. I will replace the metal nuts with ceramic at the terminals. I will secure/house each element in a ceramic tube. Then, secure the tubes inside the pipe. There will be a gap between the elements to allow cable egress through a drilled port in the tube.

Elements will be conductive and thermally insulated as well.
R/
Jared
 
CK

Quote

jbrux4 wrote:

But, do you think the in-line method is dangerous for the top element?


Inline hasn't been a problem for my roaster. You can see how they are stacked in post #29
https://forum.hom...owstart=20
and #47
https://forum.hom...owstart=40

The top element and wire connection should only see 50% of the net heat value if the heaters have equal output, so at 250C ET the top element and wires shouldn't see more than about 125C. This hasn't been a problem for the high-temperature rated wires in the transparent roaster.
 
jbrux4

Quote

CK wrote:

Inline hasn't been a problem for my roaster.


I guess I am always looking for something more familiar to what mine will be using which is a SS 2" or 1.5" pipe. I have seen all of your pics and I personally would call that a sandwich because I think the elements, I think, are disc shaped and more layered. The same concept applies, and thanks for the explanation of the element utilization under a typical scenario.

The problem, I see, for my in-line pipe is the acquisition of an appropriate ceramic tube or mica tube. I would want a friction fit for the tube inside the pipe. Even if it was somewhat loose, I could use a set screw to prevent movement. I could then perform all heating element work outside of the heat pipe and then just slip it in. This will allow for ease of maintenance/replacement/modification in the future.

Ceramic seems expensive and less workable while Mica seems less expensive and easily workable - just need to find it in the right OD and thickness. As an added bonus, I will have a fire sleeve on the outside of the heat pipe as well to help insulate - and prevent forest fires.

It's coming together in my head - just need to get more pieces to start assembling.
R/
Jared
 
jbrux4
To all,

I came to this site with an idea and a passion to build a roaster to simply get better coffee. I know that I am mostly clueless about a lot of what the experienced professionals and hobbyists have put into their roaster designs. My idea has take shape with a lot of research coupled with guidance from many. All of the help and information is much appreciated. And, because I know that I am a newbie and there are others trying to wrap their heads around it all, I will post my build sessions as episodes. This stuff may be rudimentary for some, but helpful to others. In addition, I am not trying to find and reuse parts to throw this thing together - though I admire those with the know-how and skills to do so - but, it's not just how I am doing this project. In the end, this thing will work, and this thing will last. I will get my use out of it and bring smiles, flavors, and aromas to many.

Though I have not completely decided on some design elements, the high level is this:
  1. Fluid-Bed that can do at least 600g
  2. Utilize SS and tri-clamp fittings where possible
  3. Dual 1750w, 14.5 Amp elements electrically wired in parallel on separate 110v circuits and physically mounted in-line in the heat pipe with a mica or ceramic tube for conductive and thermal insulation.
  4. Use at least 2 K-Type Thermocouples: (1) below the perf plate or screened gasket for air temp/environment temp (ET) and (2) in the top/outermost portion of the roast chamber reducer before the glass for the bean temp (BT).
  5. Utilize the TC4 to enable the capabilities of logging, monitoring, and controlling. Install potentiometers for the capability of manual control of heating and air flow.
  6. Use a thru-flow blower to heat the air prior to heat pipe entry. Also, insulate the outside of the heat pipe.
  7. Use a cyclone separator for chaff collection.
  8. Cabinet base for heat pipe and below. Exposed Roast Chamber and Chaff collector.
  9. Use an air intake silencer and employ other silencing techniques (i.e. roast chamber silicone jacket) if unable to hear first or second crack.
  10. Cool beans in chamber post roast and hopefully have enough power to eject with a slip in tube over the perf plat or gasket area.


To see my current partial BOM/procured items, see the attached file.
jbrux4 attached the following file:
partial_bom.7z [59Bytes / 682 Downloads]

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Jared
 
renatoa
The BT probe will measure anything, but not BT, in that location you want to place it.

Even if I try and still not understanding completely your 110V culture, in this specific case I don't understand why not connecting the two 110V heater elements in series, with a single SSR, to a 220V outlet, assuming such thing exist in almost all houses.

And the most personal preference... for 600 grams my experiments lead my way toward a turbo oven lid based build, after some 2-3 unsatisfactory FB contraptions.
It's a lot faster and simpler to build, and cheaper, to have a good roast from such setup, than from a FB, at this capacity, imo.
Sorry for this last paragraph rant, but the title of your thread triggered it Grin
 
jbrux4
The 220v is not convenient for me. There is one in the basement washer and dryer room. When I get back into "my house", I will gladly modify the panel and install outlets as needed. I may go back to Germany in a couple years and then switch the set-up to 220v. For my case, right now, 110v it is and will be, but the components can remain and I would only need to modify the plug input and possibly go in series with some cabling modification and a higher amperage SSR.

With the Ametek Blower stating a max CFM of 147 and the combined wattage of 3400-3500 watts, 600g is a low estimate, and I will most likely be able to get more.

Plus, with the build pieces, it all comes apart for modification down the road to upgrade and modify. These are sanitary tri clamp fittings and I can do whatever. I dont want multiple roasters, just one that can grow and change as needed.
R/
Jared
 
jbrux4

Quote

renatoa wrote:

The BT probe will measure anything, but not BT, in that location you want to place it.


Please provide your recommendation on placement and why?
 
renatoa
Before this, maybe is a wrong understanding from my part, please explain more detailed where is this location:

Quote

in the top/outermost portion of the roast chamber reducer before the glass for the bean temp


Do you mean exhaust air temperature ?
 
renatoa
Rewiring the two 110V elements from paralel to series, and connecting them to 220V will not draw more current, conversely... you can use a lower current SSR.
 
jbrux4

Quote

renatoa wrote:

Do you mean exhaust air temperature ?


Negative. It will be at the top portion, the outer most diameter of the reducer that goes from heat pipes, to roast chamber.

Currently, I am thinking 1.5" heat pipe to 4" reducer (funnel). So, at the 4" part of the funnel. Above the funnel is the glass.
R/
Jared
 
jbrux4

Quote

renatoa wrote:

Rewiring the two 110V elements from paralel to series, and connecting them to 220V will not draw more current, conversely... you can use a lower current SSR.


Thank you. Noted and put in my pocket.
R/
Jared
 
renatoa
Got it, there is good, was thinking you mean exhaust air.
The perfect place requirements are: least airflow possible, and slowest bean movement, for the longest contact possible.
Also, probe shape is critical. I would consider such sticker model for this purpose:
https://perfectpr...cts/tl0225

Sorry for confusing you more than helping.
 
jbrux4

Quote

renatoa wrote:

Got it, there is good, was thinking you mean exhaust air.
The perfect place requirements are: least airflow possible, and slowest bean movement, for the longest contact possible.
Also, probe shape is critical. I would consider such sticker model for this purpose:
https://perfectpr...cts/tl0225

Sorry for confusing you more than helping.


Wow. Didnt even know this existed. Operating temp is up to 392F. How did you overcome that limitation?
R/
Jared
 
renatoa
I would check elsewhere for versions using a better kapton tape.
According to manufacturer (DuPont) it could range up to +400 ?C / 752 ?F
 
jbrux4
THRU-FLOW Blower Question:

Well, I feel like a dummy.

I have the thru-flow blower in-hand now, but I am not getting how to get this thing installed. Is there a housing that goes over the motor that has a blower outlet that I could then attache a pipe to?

I think I now understand why people go with the Tangential Bypass - because it already has a blower outlet.
R/
Jared
 
greencardigan
Yes it will eed to be placed in some sort of housing or tube. I used PVC tube that was almost a perfect fit for my motor.
 
jbrux4

Quote

greencardigan wrote:

Yes it will eed to be placed in some sort of housing or tube. I used PVC tube that was almost a perfect fit for my motor.


As much as I have looked, I cant find a good example- less 3d printed custom stuff.

I am still laughing at myself. "Oh, it's gonna be easier one I see it and have it in-hand." I was wrong. I dont want to give up the design principle of heated air though, so I must find a way.
R/
Jared
 
greencardigan
Here's some pics from my single element roaster build. It has the motor in a PVC tube with th PVC reducer on top where the element connects to.
greencardigan attached the following images:
img_1616.jpg img_1615.jpg
 
jbrux4

Quote

greencardigan wrote:

Here's some pics from my single element roaster build. It has the motor in a PVC tube with th PVC reducer on top where the element connects to.


Thanks. Disappointment has faded and the idea juices are flowing now.
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Jared
 
jbrux4
Questions Regarding HONEYCOMB AIRFLOW STRAIGHTENER:

For those who have the know-how with the honeycomb airflow straightener:

  1. How do you trim a square straightener to round? What tool or tools did you use?
  2. Is it best to put the straightener at the ingress point or the egress point of the heat pipe?
  3. Can this substitute a perf plate/screen at entry into the roast chamber?


My use case is the following:
  1. 3/4" thick airflow straightener: https://sep.yimg....sing-5.gif
  2. Thru-Flow blower
  3. 1.5" diameter heat pipe approximately 10-12" length
  4. 2 heating elements in heat pipe approx 4.25" length each and 1" diameter each

Edited by jbrux4 on 11/11/2019 9:43 PM
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Jared
 
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