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The Basics - tools, capabilities and concepts
Alchemist
Top  #21 Print Post
Posted on 08/25/2007 11:17 PM
I suspect it may be something else. Do you want to work with it since you have it or get a George Forman with the square bores?

I will touch base with you via PM with shipping, etc.

OK, we can work with self contained. It will make the foot print larger, but that is workable. My thought with an outside control box is not kludge like. It would be a neat and tidy, well labeled control box. ONE. Thinking the variac it is large to fit inside, but doable. Since you are thinking triac, let's talk that a bit.

My understanding is they are basically timed units. You may find you get too much of a temperature flux, but I really don't know. I thought about them at some point but didn't like the lack of fine control.

But in this case, it is YOUR roaster. We can do the triac. Maybe worthwhile to set the design to accomodate both, test both and go with the one you like.

As for "Zen", in my world that means balance. If self contained makes it large and ungainly, then that isn't zen. But that may well be in the eye of the beholder.
 
Alchemist
Top  #22 Print Post
Posted on 08/26/2007 10:05 AM
Just so we are clear, when I said external control, this is the kind of thing I had in mind. Attached, but separate if you see what I mean. Modular more than anything else. Heck, the whole polished look is a nice goal in my mind. It is virtually everything we are talking about.
Alchemist attached the following image:
sampleroaster[475].jpg
 
Alchemist
Top  #23 Print Post
Posted on 08/26/2007 10:24 AM
I know before we started the thread you mentioned using encased heater elements instead of bare nichrome. The more I think about it, there is a lag time anyway with enclosed elements and the triac is mostly built for those anyway. With nichrome, I would say no way, but maybe in this case it would be fine (and definatley cheaper and NOT overengineered). I saw we give them a try.

I may go ahead and test one out with my Zen II since it has two of those elements and I use a variac. I know how it should behave so any differences should be apparent.
 
David
Top  #24 Print Post
Posted on 08/26/2007 5:50 PM

Quote

Alchemist wrote:
Just so we are clear, when I said external control, this is the kind of thing I had in mind.


Wow! That sure is red. Shock

I see what you mean about the external control box.
I don't know if I can replicate those embossed letters. ;)
So, I was thinking something more like this. It has the integrated controls. And it's a cool blue.
Note the dump mechanism.
David attached the following image:
Probat[485].jpg
 
Alchemist
Top  #25 Print Post
Posted on 08/26/2007 10:35 PM
Well, it was more the shape I was thinking. But yes, it is red. Personally, I was thinking Purple

OK, I was thinking just that style for the dump mechanism as you call it, except I would put it at the front.

Give me some feedback. I was really thinking the general shape of the red one would do the trick. The main issue I see with the blue one is frankly the compactness. We are going to be insulating the drum quite heavily (1-2" depending on what we need/want) and that is going to bulk it right up.

Is there something in particular (aside form color) that you want to attempt to incorporate into this one, or on the other hand, that you don't like (aside from the color) in the red one? And I would not say the controls are so much integrated as the roaster is sitting on top of one huge control box ;)
Edited by Alchemist on 08/26/2007 10:36 PM
 
Alchemist
Top  #26 Print Post
Posted on 08/26/2007 10:50 PM
Now, just a couple numbers to toss out to you. I mentioned I use a drum very similar to the one we are proposing in the Zen II. If I lift the end of the roaster up 3", the 2 lbs of beans I had in there stop touching the edge of the drum. The roaster is 15.5" wide. That gives us a drum tilt angle (arctangent(3/15.5)) of 11 degrees (well 10.95 but who cares).

Our first "real" number Grin
 
David
Top  #27 Print Post
Posted on 08/26/2007 10:52 PM
All kidding aside, I think both of those pictured roasters are absolutely beautiful.
So, I really have no objections to either one -- in any color, including purple! Grin

As for insulation, I have a roll of insulating blanket material, KaoWool, I think it's called. I haven't rolled it out to see how much there is. I know that enough for one home roaster like Dan's was taken from the roll. Otherwise, I think it's all there.
 
David
Top  #28 Print Post
Posted on 08/26/2007 11:07 PM
When you say "wide" you are referring to the long dimension, right?
Zen I goes north-south and Zen II goes east-west, IIRC.

Would Zen 4.2 go north-south like the red and blue ones above?

The tilt you describe certainly sounds like it would be adequate to keep the beans inside, add a little horizontal movement, and perhaps even look a little bit sexy. Nicht wahr?
 
Alchemist
Top  #29 Print Post
Posted on 08/27/2007 6:59 AM

Quote

David wrote:
All kidding aside, I think both of those pictured roasters are absolutely beautiful.
So, I really have no objections to either one -- in any color, including purple! Grin

As for insulation, I have a roll of insulating blanket material, KaoWool, I think it's called. I haven't rolled it out to see how much there is. I know that enough for one home roaster like Dan's was taken from the roll. Otherwise, I think it's all there.


I am SOOO glad you you were right there with my in the kidding.

The Kaowool should be fine. I also have looked at a number of products from Fiberfrax. I have a few pieces of the fiber board around that may find it's way into this version. Similar to this
. In classic Zen, we will focus on what there is around mainly.

To some degree, the material will depend on the final shape. Months ago I saw and worked out how to get that nice half circle curve above the drum without a brake and on full support. I plan on making use of that insight here.
 
Alchemist
Top  #30 Print Post
Posted on 08/27/2007 7:12 AM

Quote

David wrote:
When you say "wide" you are referring to the long dimension, right?
Zen I goes north-south and Zen II goes east-west, IIRC.

Would Zen 4.2 go north-south like the red and blue ones above?

The tilt you describe certainly sounds like it would be adequate to keep the beans inside, add a little horizontal movement, and perhaps even look a little bit sexy. Nicht wahr?


Oh, yes, you are correct. I lifted east/west and I think you will find that with a reasonably speeded motor (40-60 rpm) the sound of the beans in drum with this vane arrangement has a certain sexy sound to it - a rather nice double beat satin on satin sashay.

And also correct, the plan is for the Zen 4.2 to go north-south so if needed, we can look down the snout.

Although I don't plan on copying exactly, what drew my attention to the red one was the basic shape fit what was in my head, but in reality, it will be a merging of the two. We will have an incline that neither has. Will will have a cooling tray as both have (I am partial to the smooth curves of the red one). We will tip (albeit from a front grip) like the blue one. oh, oh, oh, and what do you get if you mix red and blue?Shock (Actually, you are welcome to paint or not paint it what ever color you with )

OK, I want to go ahead and finish up the basic requirements of what we want and move on to a new thread. Also, in the next day or so, I am going to put up a sticky thread of a summary of requirements and where we are on them, and a list of material in probably the same thread so we and everyone else has a concise running list for future reference. It will be an edited thread instead of a running thread.
Edited by Alchemist on 08/27/2007 7:22 AM
 
David
Top  #31 Print Post
Posted on 08/27/2007 10:08 AM

Quote

Alchemist wrote:Months ago I saw and worked out how to get that nice half circle curve above the drum without a brake and on full support. I plan on making use of that insight here.

Although I don't plan on copying exactly, what drew my attention to the red one was the basic shape fit what was in my head, but in reality, it will be a merging of the two.

That sounds good. I would like to learn that shaping technique.

Quote

Will have a cooling tray

Kewl! B)B)B)

This gets better and better!
 
David
Top  #32 Print Post
Posted on 08/27/2007 12:27 PM
Not to get too far ahead, but I have been wondering about the motor for this roaster. :(

Will we have gears or belts to turn the drum?
Or will it be a direct drive of some kind?

I have several motors that are available, but they may not be suitable for various reasons.

The two 55 rpm 1/25 HP gearmotors are mighty solid. However, if our motor is going to be attached to the drum at the back of the roaster, then we'd be lifting its 6+ pounds every time we dumped out a roast!

I also have numerous bread machine motors that need new homes. They are cheap and easy to find. In the bread machine there is a belt that turns a 5" pulley thereby reducing the drive speed to about 200 rpm. Way to fast for our drum, methinks. OTOH, our George Foreman drum is about 7'' across. Help me with the math here. Would that reduce our speed to --- about 140-150 rpm? (5/7 x 200)?
Probably still too fast. We wouldn't want the poor beans pinned up against the wall like certain carnival rides i remember getting sick on!
But you may have some better ideas about how to reduce the speed, if we go that route.

I also have a sewing machine motor, possibly two. It will run at whatever speed we choose and the speed could even be changed during the roast (or dump), if it made any sense to do that.

I could also go shipping for something. Perhaps a motor like Ron Kyle uses on his Drum. Those are 55-57 rpm and are fairly light. I have seen them on eBay from time to time.

Or maybe you had something quite different in mind. s:1


Oh, yes. What about heat transfer to the motor? How do we keep that from getting out of hand?
 
Alchemist
Top  #33 Print Post
Posted on 08/27/2007 12:57 PM
Well, roughly, here is what is in my mind and what I have been working off of from an internal concept.

Barely to scale.

We will see how close it comes in the end.
Alchemist attached the following image:
zenfront[488].jpg
Edited by Alchemist on 08/27/2007 1:02 PM
 
Alchemist
Top  #34 Print Post
Posted on 08/27/2007 1:04 PM
And from the side.
Alchemist attached the following image:
zenside[489].jpg
 
Alchemist
Top  #35 Print Post
Posted on 08/28/2007 7:42 AM
In general, my preference is for a direct drive motor without a bunch of pulleys or reducers. I say let's look at the RK type motor.

Now, if you check out the rough drawing I did, there is some space in the bottom for some pulleys and might work for the cooling tray stirring motor (if you want to stir AND blow on the beans). I think 150 rpm there would be ok.

With the motor hanging off the back and in the open, heat should not be any concern at all. Good thinking though.

Aren't sewing machine motors pretty heavy also? I DO like the idea of slowing it at dump. Talk to me about weight and dimensions here. Can we control it with a dimmer?
 
David
Top  #36 Print Post
Posted on 09/04/2007 9:07 AM
New tools obtained this past weekend:
18" metal bending brake,
5" vise, and
8" table top drill press

Grin.
 
Alchemist
Top  #37 Print Post
Posted on 09/07/2007 11:28 AM
Hey, congratulations. Are you cool NOT using the brake for this project? I personally would like this doable by anyone with basic tools. The vise and drill press I think are fine. The press makes life easier but should be fully doable free hand also.
 
David
Top  #38 Print Post
Posted on 09/08/2007 2:47 PM
I agree that the design should be doable without the bending brake.
But to agree in advance not to use my new toy, um, tool, that may be too much. ;)
Edited by David on 09/09/2007 10:46 PM
 
David
Top  #39 Print Post
Posted on 09/08/2007 2:49 PM
Looking at the drawing above with the external motor and tipping mechanism got me wondering if we were going to have a wire (perhaps coiled) hanging down off the back or it would be located inside or just what?
:(
David attached the following image:
ZenPivot[504].jpg
 
Alchemist
Top  #40 Print Post
Posted on 09/08/2007 5:19 PM
I plan to keep it contained in a conduit running along the outside of the insulation but inside (i.e. invisible) the roasting case (not chamber).
Alchemist attached the following image:
ZenPivot[504][505].jpg
 
David
Top  #41 Print Post
Posted on 10/06/2007 6:04 PM
You suggested in another thread that we might build this in "tandem."

While I like the idea of working from your plans, I can see that following your lead in the actual building could be even better.

If you are willing to build a piece, take pictures and then post them; that could be a lot easier for me as I would be better able to visualize what is going on. I might need several camera angles to really understand.

:(

That said, if you are willing then I certainly am. B) Grin
 
Alchemist
Top  #42 Print Post
Posted on 10/06/2007 9:29 PM
I am good for the start at least. I don't think I can commit the time to build the whole roaster right now, but I do think I can do the cooler. My hope in that case would be that you get to see how my drawings and language turn into a 3-D manufactured item.

Does that work? If so, I will review things, see what other parts we need and get some things posted.
 
David
Top  #43 Print Post
Posted on 10/07/2007 12:41 PM
OK. I understand about the time and I have similar constraints.
Onward with the cooler! Grin
 
Alchemist
Top  #44 Print Post
Posted on 11/03/2007 12:49 PM
I have modified my Zen II to use two 500W halogen bulbs in lieu of one of the 10 amp tubular heaters.

Yesterday one of the bulbs blew. Being left is only 15 amps of roasting power, I decided to try a 1 kilo test. Basically a proof of concept for the Zen 4.2 here.

I preheated to 450 F and loaded the beans. Since I have to complete open the roasting chamber to load, th temperature dropped to 275 F. It quickly recovered to a reasonable 350+ in about 2 minutes, and steadily climbed. I had the first outliers of 1st at 11:30 and a solid 1st crack at 12:30. I started pulling the power back at the 11:45 mark so I didn't roll directly into 2nd. A kilo of beans produces quite the amount of smoke and 1st goes on and on. 1st finally finished up (as I kept pulling the power back) around 14:00. I stretched the start of 2nd out to 15:30. At the first snaps of 2nd I pulled the roast.

So there we go. I have solid data we can do 1 kilo on 15 amps in what I consider reasonable time, in a moderately insulated roaster, with power to spare at the end.

I am having 2nd thoughts about the afterburner. I am not sure if we can indeed burn off that level of smoke on the power we have. My plan will be to use that same burner as a heat source for the beans, but even so. Worst case we design it in and if it doesn't work, then we really have nothing lost.

Finally, I had a 11.5" x 3" cake pan I dumped the beans in. About 2" deep. A kilo is a LOT of beans and took quite the air flow to cool. You may be right about your concern about the little tangential blower not being up to the task. I have never cooled that many beans before. But again, it isn't wasted money. If it doesn't work I will want to use it for our motor and wiring space cooler.
 
David
Top  #45 Print Post
Posted on 11/03/2007 11:13 PM
Nice proof of concept, sir. A kilo with a single 500 watt halogen plus one of the 10 amp tubular heaters, right?

It would be nice if we could all that smoke. I'm not at all certain that we can reduce it enough for this baby to be an "indoor" roaster. Agreed: no harm in playing with the afterburner design.

Thanks for the details of the trial roast.
 
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