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Dan's Direct-Flame Roaster
coffeeroastersclub
Top  #51 Print Post
Posted on 03/21/2011 9:27 PM

Quote

Dan wrote:
Beaner, Good thinking. That might work. I think I have a miniature version of that somewhere in my bins. smile I finished welding the chain on the bowls today. I would have gotten more done, but had to make some patterns, RTV molds, and urethane parts for work instead.


Dan,

If the weight of the handle was just right you may not need to have it clamped down at all; just "resting" on a greased rounded notch. I would think that the sprockets going into the welded on chain, if both sprockets were tilted back just a tiny bit, would allow the roasting chamber to stay put. Of course that angle tilted back also applied to the cut of the rounded notch for the back handle rest. B)

Len
"If this is coffee, please bring me some tea but if this is tea, please bring me some coffee." ~Abraham Lincoln
 
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Dan
Top  #52 Print Post
Posted on 03/22/2011 3:22 PM
Len, You might be right. I don't know how the drum will react with the beans jumping around; they will outweigh the drum 2:1. I'll do some tests and see how it reacts. Who knows, maybe it will sit just fine as you say. Or, perhaps a bungee cord might be enough to restrain the handle bearing.
Edited by Dan on 03/22/2011 3:23 PM
 
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coffeeroastersclub
Top  #53 Print Post
Posted on 03/27/2011 2:19 PM

Quote

Dan wrote:
Len, You might be right. I don't know how the drum will react with the beans jumping around; they will outweigh the drum 2:1. I'll do some tests and see how it reacts. Who knows, maybe it will sit just fine as you say. Or, perhaps a bungee cord might be enough to restrain the handle bearing.


Dan, I was thinking about the heat source you intend to use and something came to mind. You ever see those propane infrared heat sources they put on the ends of propane tanks:

ecx.images-amazon.com/images/I/51R3NR355YL._SL500_AA300_.jpg

I wonder how that would work in your roaster. Seems it may be a benefit having that type of heat source within the stainless drum globe you are making.

Len
"If this is coffee, please bring me some tea but if this is tea, please bring me some coffee." ~Abraham Lincoln
 
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Dan
Top  #54 Print Post
Posted on 03/28/2011 12:53 PM
Len, I have no doubt that that heater would roast coffee. It's circular design should make it work for a lot of roasters. However, for what I'm trying to do, that won't work. Some of the earliest gas fired roasters were direct-flame. It was said that these produced superior coffee than the Jabez Burns style of indirect heat drum roaster where the burner was outside of the drum. In order to verify their claim, I have to make a test model as close to their specifications as possible. The most important aspect is that the beans should fall through the high temperature flame. Since catalytic heaters don't have a flame, per se, that won't work for me. I do know that they are supposed to be very efficient and they create lots of infrared emissions.

I made a little progress on the roaster over the weekend, but not enough for a report and photo.
 
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Dan
Top  #55 Print Post
Posted on 04/02/2011 3:34 PM
Here is how I configured the rear bearing and handle. The bottom of the bowl was oil-canning, so I added the tripod bracing. The oilite bearing spins on the rod inside, so the grease won't be on the outside, less messy that way. I added some rear vent holes, too.

claycritters.com/coffee/bollinger_flame_roaster/bfr8.jpg
 
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coffeeroastersclub
Top  #56 Print Post
Posted on 04/03/2011 12:20 AM

Quote

Dan wrote:
Here is how I configured the rear bearing and handle. The bottom of the bowl was oil-canning, so I added the tripod bracing. The oilite bearing spins on the rod inside, so the grease won't be on the outside, less messy that way. I added some rear vent holes, too.

claycritters.com/coffee/bollinger_flame_roaster/bfr8.jpg


Dan,

Nice professional work. Are you a machinist by trade?

So the bearing will just rest on a rounded grove? Also, the holes on the bottom, for ventilation?

Len
"If this is coffee, please bring me some tea but if this is tea, please bring me some coffee." ~Abraham Lincoln
 
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Dan
Top  #57 Print Post
Posted on 04/03/2011 5:06 AM
Len, I'm an Industrial Designer, so I'm comfortable with machine tools, at least as far as making models, patterns and molds. A REAL machinist wouldn't have run a piece of allthread through all those parts, he'd have threaded the ends of a rod. smile

The bearing will drop into a U-shaped holder, probably with a quick release clamp holding it down.

You are right, the holes are for ventilation on the rear of the machine. From what I can tell, direct-flame roaster drums had a decent air flow through them. Who knows, I might have to add a second ring of holes later.
 
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coffeeroastersclub
Top  #58 Print Post
Posted on 04/03/2011 1:53 PM

Quote

Dan wrote:
Len, I'm an Industrial Designer, so I'm comfortable with machine tools, at least as far as making models, patterns and molds. A REAL machinist wouldn't have run a piece of allthread through all those parts, he'd have threaded the ends of a rod. smile

The bearing will drop into a U-shaped holder, probably with a quick release clamp holding it down.

You are right, the holes are for ventilation on the rear of the machine. From what I can tell, direct-flame roaster drums had a decent air flow through them. Who knows, I might have to add a second ring of holes later.


Dan, do you feel secure that beans will not escape through the holes?

Len
"If this is coffee, please bring me some tea but if this is tea, please bring me some coffee." ~Abraham Lincoln
 
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Dan
Top  #59 Print Post
Posted on 04/03/2011 2:17 PM
Len, I think it will be OK. I plan on angling the ends of the vanes a little toward the center.
 
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Dan
Top  #60 Print Post
Posted on 04/17/2011 7:11 PM
I made some progress. The drive train is installed and running, and I have the rear bearing support. All I need to do next is install the vanes. I made a cardstock pattern for them today.
claycritters.com/coffee/bollinger_flame_roaster/bfr9.jpg
 
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seedlings
Top  #61 Print Post
Posted on 04/18/2011 8:09 AM
I love the drive system - how elegantly simple it is - just lift off the drum. Very, very nice.

CHAD
Roaster: CoffeeAir II 2# DIY air roaster
Grinder: Vintage Grindmaster 500
Brewers: Vintage Cory DCU DCL, Aeropress, Press, Osaka Titanium pourover
 
JETROASTER
Top  #62 Print Post
Posted on 04/18/2011 10:20 AM
Gorgeous! -Scott
 
Dan
Top  #63 Print Post
Posted on 04/18/2011 10:37 AM
Thanks, guys! The sprocket/drive is a bit herky-jerky. That's because the sprockets were designed to run inside the curve of the chain, not on the outside. It spins OK, even with no beans in it, but it is noisy. I can deal with this later. I need to add a clevis pin to trap the bearing in the slot.

I can't wait to try this out and work up some profiles. I should order some cheap Brazilian beans for testing.

 
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seedlings
Top  #64 Print Post
Posted on 04/18/2011 3:01 PM
VFD for motor control?

CHAD
Roaster: CoffeeAir II 2# DIY air roaster
Grinder: Vintage Grindmaster 500
Brewers: Vintage Cory DCU DCL, Aeropress, Press, Osaka Titanium pourover
 
Dan
Top  #65 Print Post
Posted on 04/18/2011 3:15 PM
I thought about a VFD, too. It would work fine, but I'm not prepared to invest too much in an experimental roaster, at least not yet. Finding fractional horsepower 3-phase motors can be a challenge, but when you do, the used ones are dirt cheap. The advantage would be being able to direct drive the sprocket.
 
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coffeeroastersclub
Top  #66 Print Post
Posted on 04/30/2011 9:24 AM
Hello Dan. How's the roaster coming? I was wondering if you were finding the chain/sprocket system jumping a bit; and if so I was wondering if some high temp food quality lube on the chain may help in that. smile

Len
"If this is coffee, please bring me some tea but if this is tea, please bring me some coffee." ~Abraham Lincoln
 
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Dan
Top  #67 Print Post
Posted on 04/30/2011 9:44 AM
Len, Thanks for asking. I'm making slow progress right now, cutting out the vanes. I ground the sprockets slightly, which helped with jumpiness a lttle. Funny thing is, the faster the drum spins the less the jumpiness! I'm not too concerned, this was just a test unit anyway. If this proves to be a good roasting machine I'll redesign and convert it to a direct-drive gearmotor with the drum supported by phenolic rollers.
 
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coffeeroastersclub
Top  #68 Print Post
Posted on 05/01/2011 10:36 AM

Quote

Dan wrote:
Len, Thanks for asking. I'm making slow progress right now, cutting out the vanes. I ground the sprockets slightly, which helped with jumpiness a lttle. Funny thing is, the faster the drum spins the less the jumpiness! I'm not too concerned, this was just a test unit anyway. If this proves to be a good roasting machine I'll redesign and convert it to a direct-drive gearmotor with the drum supported by phenolic rollers.


Are you having some difficulty determining the curvature of the vanes as they meet the inside of the unique inside drum surface you have? If so, there is a pin type tool that you can use to push against the inside of the drum to determine the curve, then trace that to the metal you are cutting for the vanes. I forget the name of the things :@; I have one buried in my shop and use it every now and then.

Len
"If this is coffee, please bring me some tea but if this is tea, please bring me some coffee." ~Abraham Lincoln
 
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Dan
Top  #69 Print Post
Posted on 05/01/2011 12:44 PM
Len, I know what you mean, I have a couple of those template tools, one is 24" long! What I used was chipboard marked with a divider. The tips of the vanes will angle slightly, so they had to be rescribed. I have the vanes cut and tabs bent. Now to bolt them in. I'm close to testing this, but not this weekend. I have to go into work this afternoon to install a new machine PLC controller.
Edited by Dan on 05/08/2011 1:47 PM
 
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Dan
Top  #70 Print Post
Posted on 05/08/2011 1:48 PM
The vanes are ready to install. The ends are angle upward to move the beans away from the open ends of the drum and to direct the beans over the flame. I'll probably flip up the trailing edges so the beans rise up further in the drum before falling back down.

claycritters.com/coffee/bollinger_flame_roaster/bfr10.jpg
 
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Dan
Top  #71 Print Post
Posted on 05/21/2011 3:44 PM
The vanes are mounted. Finally! I tested the vane action with three pounds of green. The beans are lifted high, and cascade with a uniform pattern. It will be easy to intercept them with the flame. Now all I need is a dry day to set everything up outside and do the first roast.
Edited by Dan on 05/21/2011 4:15 PM
 
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seedlings
Top  #72 Print Post
Posted on 05/23/2011 9:53 AM
Nice! Can't wait to see this one in action.

CHAD
Roaster: CoffeeAir II 2# DIY air roaster
Grinder: Vintage Grindmaster 500
Brewers: Vintage Cory DCU DCL, Aeropress, Press, Osaka Titanium pourover
 
Dan
Top  #73 Print Post
Posted on 05/23/2011 10:43 AM
Hey, maybe I could post a video on YouTube. Does anyone know if I have to do something special to make my camera's MOV file work/compress for YouTube?
 
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JETROASTER
Top  #74 Print Post
Posted on 05/23/2011 10:47 AM
Dan, If I can do it.....anyone can do it. My Droid X spits out .mov files, and I had no problem.
...Looking forward to it. -Scott
 
coffeeroastersclub
Top  #75 Print Post
Posted on 05/23/2011 12:33 PM

Quote

Dan wrote:
Hey, maybe I could post a video on YouTube. Does anyone know if I have to do something special to make my camera's MOV file work/compress for YouTube?


Dan,

Youtube has 10 minute run time limitations as far as I know. If you have issues with it please feel free to use www.InstantMovies....

I own the site and you can post your video there (no charge), under "instructional videos". There is no time limits on that site.

Len
"If this is coffee, please bring me some tea but if this is tea, please bring me some coffee." ~Abraham Lincoln
 
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