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Part 10 - Convections
Alchemist
Top  #21 Print Post
Posted on 09/24/2007 9:56 PM
BTW, I just realized something. Assuming we do gang these, we don't ever want both dampers fully in A/C mode. If we do, all cooling effect stops as all convection to and from the drum is cut off. 50% - 75% flaps may be all we want/need. That way we always have air moving through the system.
 
Alchemist
Top  #22 Print Post
Posted on 10/30/2007 4:22 PM
Alright, I have been thinking about this a lot and am confident that the blower fan from Grainer I speced out and piece of sink plumbing (the 90 degree bend drain pipe - $7-8) will let this work just fine.

Would you review the blower $$'s vs building our own from parts and let me know what you think. Are you good going with the off the shelf unit with modifications?
 
David
Top  #23 Print Post
Posted on 10/31/2007 2:26 PM
I went by a local Grainger outlet today and looked at some of their small centrifugal blowers. I checked out the one you mentioned above [4C761] as well as it's replacement, the 1TND4. I also compared the 1TDN3, which has a smaller wheel and motor. It has about the same cfm rating via faster RPMs. I chose it because I thought the lower profile would be better for our use.

Here's the link for this small blower. It was $41.95. I hated to spend that much, but we'd end up spending close to that if we did it piecemeal after counting shipping.

They had a high-temperature model for only twice the price!!
I asked about shaft extenders, but they did not have any in their catalog.
So, we'll need the ones that you sourced as while back.

I'll take some pictures as I disassemble it so you can design the ductwork.
 
David
Top  #24 Print Post
Posted on 11/04/2007 12:33 AM
You said in another thread that you found that a kilo filled your 11.5 inch bake pan to a depth of about 2 inches. How big a pan diameter would we need to reduce that to about 1 inch?

The cooler blower --
I am a bit spoiled in this regard as my two coolers are powered by 1) a leaf blower and 2) a blower assembly salvaged from an old clothes drier! Shock

Along those lines, I found this blower the other day and got one to try out. Actually I got mine via Amazon for a better price/shipping combo. If someone goes looking for this item on eBay, beware, as it is offered by at least three sellers at three different prices and three different shipping costs. YMMV. I wouldn't pay over $15 for it. I thought it looked lke a toy at first. But I saw that it had a place to insert new motor brushes, which is more than I can see for my full-sized leaf blower.

In any case it is a lot smaller than a regular leaf blower, but it puts out a substantial volume of air at a pretty good pressure. The problem with it for our purposes is that the motor sticks out quite a ways from the impeller blade. Actually the full depth [from base to the top of the volute] is a little under 6 inches, but I still think it's too tall.

And, you may not even want to consider something with a universal motor with all its noise.
David attached the following image:
Compare2GF[571].jpg
 
David
Top  #25 Print Post
Posted on 11/04/2007 12:38 AM
I looked for sheet metal a few days ago and found that the Big home improvement stores only carried 24" x 30" stock. I think we need a sheet that is 48" to put a skin around the front of the cooler, right?

BTW, what thickness shall I look for next trip out? Please tell me in inches and/or gauge for aluminum and for galvanized steel. Tnx.
 
Alchemist
Top  #26 Print Post
Posted on 11/05/2007 2:02 PM
I was a little off on the 2" deep. It was 1 1/2". To drop that to 1" the diameter would have to increase to 14.75".

As for the sheet metal, don't get ahead of me. smile the 24" x 30" will be fine. We'll lap it on the sides if we need. I don't know thickness or gauge yet.

I like the looks of the blower. Do you want to consider designing it in in lieu of the tangential blower. For cooling, I could hardly care less about noise. It is a fine size to fit in if you test it out and think it will cool well.
 
David
Top  #27 Print Post
Posted on 11/05/2007 3:27 PM

Quote

Alchemist wrote:I was a little off on the 2" deep. It was 1 1/2". To drop that to 1" the diameter would have to increase to 14.75".

And you said that we'd have room for that size.

Quote

As for the sheet metal, don't get ahead of me. smile the 24" x 30" will be fine. We'll lap it on the sides if we need. I don't know thickness or gauge yet.

Ahead of you? Hah! I was just looking. Didn't even have my wallet out. ;)

Quote

I like the looks of the blower. Do you want to consider designing it in in lieu of the tangential blower. For cooling, I could hardly care less about noise. It is a fine size to fit in if you test it out and think it will cool well.

Yes, let's try it out.
 
Alchemist
Top  #28 Print Post
Posted on 11/06/2007 7:03 AM

Quote

David wrote:

Quote

Alchemist wrote:I was a little off on the 2" deep. It was 1 1/2". To drop that to 1" the diameter would have to increase to 14.75".

And you said that we'd have room for that size.


Meaning you do or don't want that size? And did I? Right the moment the width is 16" total, and we need 1.5" (3/4" x 2) for the angle aluminum frame. So 14.5" is what we have to work with, minus a little for tolerances and clearance. Do you want to see if you can find a 14"?

Quote

Quote

I like the looks of the blower. Do you want to consider designing it in in lieu of the tangential blower. For cooling, I could hardly care less about noise. It is a fine size to fit in if you test it out and think it will cool well.

Yes, let's try it out.


OK, can you get me some more views, dimensions, etc. I need to work out how to mount it. Anything obvious since you have it in hand?
 
David
Top  #29 Print Post
Posted on 11/06/2007 9:09 AM

Quote

Do you want to see if you can find a 14"?

Yes, I'll check out the 14"

Quote

OK, can you get me some more views, dimensions, etc. I need to work out how to mount it. Anything obvious since you have it in hand?

Here's another view. I'll take some more pix and post them also.
David attached the following image:
2ndViewBc[578].jpg
 
David
Top  #30 Print Post
Posted on 11/06/2007 10:30 AM
The most comprehensive source of inexpensive pans appears to be sugarcraft.

They have 14x3 for $13.46 and 14x4 for $19.46. [Certain brand names are a bit higher.]

OTOH, a great source for cheesecake pans seems to be cooksdream where the 14x3 is $22.11. I talked to them and found them to be very friendly. Plus, they take PayPal!

At the moment, I'm thinking that I'd like to go with the 4" depth. That would give us room for any bouncing beans, as well as allowing some metal to work with if we decide to put on a pouring spout or funneling lip of some kind.

What do you think at this point?
 
Alchemist
Top  #31 Print Post
Posted on 11/07/2007 7:40 AM
Well, the first thing I notice from sugarcraft is:

NOTICE: Pans are NOT returnable. Please choose carefully.

Let's be sure this time.

At this point I am going to leave you in the driver's seat for making the decision. If you want 4" deep - ok. We will have to increase the lower area an inch, but I don't have a problem with that. Same with bottomless cheesecake pan vs one we have to drill out. Your call - either will work and I will design around the parts you have. I will say let's not go above 14" though. That top edge piece of sheet metal is going to be thin enough as it is, but that is ok. I just went and sketched it out and with a 14" pan, and 16" total width, we will have to use 3/4" angle for the frame, but can eliminate the set of supports I had drawn in. There will be no need for them with the pan edge being so close to the frame edge.

As for the blower up there, it is my turn to be officially confused. Those two photos don't look like they are showing the same blower at all, except for the Blue. The nozzle is the only thing I can match up . :(

Well, I guess now that I have them side by side, they are a little closer, but some base proportion seems "off"
Alchemist attached the following image:
blowerview[579][583].jpg
Edited by David on 11/08/2007 7:56 AM
 
David
Top  #32 Print Post
Posted on 11/07/2007 8:53 PM
With the able assistance of #2 grandson, Erik,
we will now demonstrate the forward half-somersault with a quarter-twist.
David attached the following image:
Erik_Shows_How[580].jpg
 
Alchemist
Top  #33 Print Post
Posted on 11/07/2007 10:27 PM
To use this David, we are going to have to take it apart and get that switch out of there and work out mounting. Given it is just a plastic housing I don't see a big deal in attaching it. It isn't going to show so likewise I don't see a problem hacking the handhold grip off of the motor area, just so long as it doesn't compromise the air flow path.

First things first. Can you see how to get it apart?

Oh, and nice work there with the flip and twist!
Edited by Alchemist on 11/07/2007 10:28 PM
 
David
Top  #34 Print Post
Posted on 11/08/2007 1:02 AM

Quote

Alchemist wrote:Can you see how to get it apart?

The first part is child's play; just four screws. We ran out of time this evening, however, and Erik got tired of looking at the flash. c:2

Here the master of the B&D electric screwdriver holds up his work.
David attached the following image:
ChildsPlay1[582].jpg
 
Alchemist
Top  #35 Print Post
Posted on 11/08/2007 7:19 AM
Beautiful. Where does that black bag go that is in the full blower shot? Over the inlet? Seem air should blow into the bag, not be drawn through it.

Can you give me a Rotate Forward view, maybe 70 degrees so I can see "inside" at an angle.

WAY to go Erik.
 
David
Top  #36 Print Post
Posted on 11/08/2007 11:28 AM
I started to take the wheel off this morning and took this picture. I got as far as removing the central nut and lockwasher before other chores called me away.
David attached the following image:
WheelView[584].jpg
 
David
Top  #37 Print Post
Posted on 11/10/2007 5:15 PM
Returning to the scene of the Child's Play, I promptly found that I could not easily get the blower wheel to come off. I struggled mightily and yet gently as I feared that I would break it. I even called Dan for a some technical assistance. He assured me that the presence of the nut and lock washer meant that it was a press fit and that it should come right off. This news increased both my hope and frustration. He told me several ways to pry/lift/jar it loose, but to no avail.

Returning to it today with a fresh, positive point of view, I was again stymied. So I called Dan again for more advice, since my technical assistance case number was still active. He gave me more reassurance (and sense of frustration) when he told me that he had opened his identical blower and the wheel came right off into his hand. Great, that's really swell. It was all I could to to put down the Sawzall and step away from the defenseless blower.

Fortunately, #1 son came by around that time wanting to borrow the car. He-heh.
Sure, in exchange for your gear puller. Mirabile dictu, he found it without a major excavation of the garage. The feisty little blower wheel did not have a chance against the leverage of that wondrous tool.

The blower quickly gave up the rest of its secrets,
which are revealed in the pictures below. (No major rotations, sir.) c:1
David attached the following image:
BlowerDisassembly3[597].jpg
 
David
Top  #38 Print Post
Posted on 11/10/2007 5:20 PM
From the base to the upper edge of the shell is 3 1/8" and to the top of the shaft is 5 3/8"
I took three pictures, but couldn't get a good angle on it. So, I have marked the correct points in the picture.
David attached the following image:
7MotorHeight[598].jpg
 
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