Evaporator Hood Plans

[DavyJones]

With the success of my evaporator drawing last year. I plan on making this hood in the next couple of weeks I decided to post my new drawing of the hood. A freind of mine has an HVAC shop and said he could bend this up for me no problem. I'll either rivet this together or solder it. I plan on making this from whatever galvanized or aluminum or SS he has that will be cheapest and a good sturdy gauge. I used google sketchup again. A few people have used my plans to build their own evaporators this past year I wish them all the best of luck. I'm going to post those again here in this thread just in case there are some new folks that might be interested. If anyone uses the plans for my evaporator or hood and make any modifications please let me know I will gladly post those on google sketchup. If you've got any other drawings of home made maple syrup processing equipment you've done in google sketchup I'll post those too.

The 6" vent I am hoping is going to be good enough. I plan on just putting in a 6" starter coller and then attaching several feet of straight duct probably 3'. In turn I am going to get some 7" that I will run through the roof. The 6" will fit into the 7" and I will be able to raise and lower my hood. I can keep it down low on my pan since it will have 2" clearence on each side then once it heats and starts a nice draw I should be able to raise it up. I am not sure what type of contraptrion I was going to make to be able to raise and lower it I was thinking of some angle whatever material the hood could sit in and attach some wire cable at each corner then connect those 4 cables to one and run it through a pulley to a trailer winch or something. I suppose if I get some good guage material to make this thing I can just screw some eye hooks in at the corners and attach my cable there and hoist it with the same idea of using a old trailer winch.

http://www.jonzilla.com/TheBittners/images/Evaporator_hood.jpg

There are 4 revisions. 2 of them (a + c) have the stack located on the side and I have adjusted the side length from 3" to 12" this will allow for clearence of a pre-heater. My pan and pre-heated are 8" so a 12" side will allow this to set 4" over the main pan

2 of the revisions (b + d) move the stack to the top of the hood

Revision a (http://sketchup.google.com/3dwarehouse/details?mid=c1147a19b48e4144fe99002354e8b16e)
Revision b (http://sketchup.google.com/3dwarehouse/details?mid=c4d0c27c169066f9fe99002354e8b16e)
Revision c (http://sketchup.google.com/3dwarehouse/details?mid=8983eb52d5dcfe4bfe99002354e8b16e)
Revision d (http://sketchup.google.com/3dwarehouse/details?mid=f480aabf38d56364fe99002354e8b16e)

http://www.jonzilla.com/TheBittners/images/Evaporatora.jpg


The links to the evaporator from last year are:

Evaporator all together (http://sketchup.google.com/3dwarehouse/details?mid=6d3b7aac2c1bc2ccb9dad9b1ca6d8652)
Exploded view (http://sketchup.google.com/3dwarehouse/details?mid=49beef89200472b14b1caddec242e4d5)


I hope everyone has a great season.

David

2008 Tapping Season Pictures (http://www.jonzilla.com/thebittners/dispphotos.asp?path=pictures/2008\Maple Syrup/)

[maple flats]

I don't see a drain for the hood. I hope it is on the other side. The hood will condense heavily on the inside and this should be drained to collect in a bucket for use and so you don't need to evaporate the same again.
I made my hood similar. You will want a door to see inside while using, add defoamer etc without lifting hood. Also, for the hood raising I riveted an aluminum angle piece at each corner, extended it a few inches above the corner and this is where i hooked my lift cables. I use a small winch to pick mine up, goes straight up and when I lower it the hood sets right back in place. I have the hood about 1/2" oversized both ways and the angle piece used to lift also extends about a 1/2" below my drain gutter to hold the hood aligned with the evaporator. I hope these help.
Dave

[DavyJones]

I don't see a drain for the hood.... I hope these help.
Dave

Dave, Thanks you bet it helps... I did add a gutter on the inside I just haven't figured out how I was going to attach a little drain yet. My gutter is a 1/2" lip if you have google sketchup you can rotate the pic and look up inside it. Sounds like I had the same idea with a little winch I'm glad I was on the right track. I didn't think about a little door thats a good idea. I was going to keep mine raised up. I thought once this get's hot from the steam it's just going to naturally create a draw and I could lift it up enough to be able to watch it boil. Maybe not, any reason why you keep your's down all the time? Can you raise it up once it gets hot?

[Haynes Forest Products]

DavyJones; What size is the evaporator and why so big and tall ? I can pick up my 3X10 hood by myself. I understand you need some room for preheater. Bucket Head has nice potos of his rig doiling and it shows how steam doesnt raise the way we think it does. Steam is heavy and in a coold sap shack it will sink check out the syrup pans and the steam drifting away frum under the hood.

[DavyJones]

DavyJones; What size is the evaporator and why so big and tall ? I can pick up my 3X10 hood by myself. I understand you need some room for preheater. Bucket Head has nice potos of his rig doiling and it shows how steam doesnt raise the way we think it does. Steam is heavy and in a coold sap shack it will sink check out the syrup pans and the steam drifting away frum under the hood.

Hmmm.... not sure why it's so big. My primary reason for the dimensions I choose is first off my pan is 2'x3' so I made it fit over my pan. The height I choose because it's pretty close to an 8' sheet. I figured the height to be about 3' just a guess though. I'm certain I'll be able to pick this up.

[maple flats]

You can pick it up by hand but when hot I don't like to. I can raise mine while operating but have only done that to show visitors what is inside. To run a preheater you are best to keep it lowered. And for optimum results you should ever have a damper. Mine however does not have a damper. And mine has 2-10" stacks (actually 10" take offs increased to 12" which goes up 6', above this and suspended from up in the cupola on a steel rod thru the center I have 10" and this telescopes into the 12, I get almost 100% steam removal on mine and neither steam stack goes outside, only up into the cupola and adjacent to the open doors) My hood is 3' wide x 90" long on a 3x8 evaporator, with the part over the syrup pan about 12-16" above it.

[Bucket Head]

Davy,

Those are nice plans! I thought I was doing good with my pencil, paper, ruler, and a big eraser!!

You should try to make your hood as low as you can, but still leave enough room for a pre-heater. I drew up my pre-heater before I started the hood. That way there was no wasted space, wasted aluminum, and additional height.

I like the arch. Just try to get the fire up to the bottom of the pans as best you can. My arch was all open when I got it. I welded in a partition that forced the fire/heat up to the rear pan.

Also, your going to want a bigger outlet/stove pipe opening. Or better yet, an actual base stack that has the correct sizing to it. You can add a damper if you think your losing too much heat. Mine had only a 6 or 8 inch stove pipe on it originally. We had a lot more fire and smoke than we had pipe to handle it. Every time we opened the door the first season, we got a facefull of flame and smoke.

Surprisingly, our eyebrows did grow back. LOL!

Again, looks good and good luck.

Steve

[DavyJones]

Davy,

Those are nice plans! I thought I was doing good with my pencil, paper, ruler, and a big eraser!!...
Surprisingly, our eyebrows did grow back. LOL!
Again, looks good and good luck.
Steve

Steve, Thanks I actually built this evaporator and used it last year it worked great... I've had email from a couple others that have built this, this past year, and will be using their's this season. I drew up the plans after it was built. I was probably boiling down upwards of 5 to 6 gallons an hour. Last year all my boiling was done outside as you can see in the pictures. The reason for the hood is I will be moving the evaporator inside my shed this year. So far all my "design on the fly" has worked out ok. I might add a layer or 2 of fire brick on my slope to see if that improves anything, get the heat close to the bottom of the pan I've read a few people have done that. I'm pretty happy with the 5 to 6 gallons an hour though. We're not tapping allot of trees and with that rate I can keep pretty much ahead of things. Evaporator Project Pictures last year (http://www.jonzilla.com/thebittners/dispphotos.asp?path=pictures/2008\Maple Syrup Evaporator Project/)

[Bucket Head]

Davy,

It looks better in action than it does on paper! I like it more now!!

That is a great photographic documetation of start to finish and then in use.

I hope all the do it yourselfer's here take a look at your photos.

Good luck this season.

Steve

[SeanD]

I second Bucket Head. The pictures are great and the google program looks awesome. I can;t wait to tinker around with it. One question I have for you or anyone else who built their evap. with an angle iron frame.

What do you do on top of the evaporator to keep the pans from getting bumped/slid off accidentally? Is it just not an issue or is it a good thing to be able to slide it straight off? I'm going to be trying my hand at welding this spring and was hoping to get far enough to make an evap.

Could the top rails of angle iron be turned 90 deg. to make an L - shaped seat for the pans without any structural problems below?

Sean

[Haynes Forest Products]

Full pans are hard to bump of the arch plus you get used to not walking to close because there "HOT" my pans tend to space out over and hour or so and I didnt have clamps on them so I have to push them back every so often. Its not vibration that does it its the ends of the pans during a hard boil pushing against each other. Depending on the size of your pans I think your arch will be stronger if the angle forms a overhang and allows for brick or blanket to fill it the void under the overhang. I like the ability to slide my pans off the arch by twisting them so you can get your hands under them. If you had to pick them up and over it would be a pain.

[Bucket Head]

I agree with Haynes. When I first started to modify my arch, I contemplated changing the angle around. I too thought about the added hasle of getting the pans off. We originally "batched it", so we would pull the pans when we got to syrup.

I do not know how much the pans weigh with liquid in them, but they stay put.

Steve

[lpakiz]

On my home made system, I welded a short piece of 1/4 inch rod (about 2 inches) on each of the four sides of the flat pan rail. Tack on the outside edge only and leave a 1/16 or so of wiggle room.
It's easy to lift the pan over them and then lower and drag the pan over the rods. They center and locate the pan very nicely when returning the pan to boil position.

[MFarmall]

SeanD, on the evaporator I made I cut some 1" angle about 1 1/2" long (8) and put one on each front corner, 1 on each side at rear of syrup pan, and 1 a fourth of the way back and from the rear of the flue pan. Tapped the frame with 1/4-20 so can swivel them down if not needed or move them up in case pans try to move. Put them down to remove pans by slidding them off. Not sure if will need them but at least they are there.
Mel

[Smitty]

Sean,
Turning the angle iron 90* will not weaken the structure, it will also eliminate
coping the vertical supports, but i think a lip or seat will make removal the
pan more difficult. The pan with sap in it is fairly heavey, and would require
a hard bump to move it.

[Smitty]

Davy,
You can pick up a brass nipple at your local hardware store, 1/4" pipe thread on one end and 5/16 hose barb on the other. Bore the perfect size
hole in the outside of your hood (in the bottom outside corner of your condensation rib) and thread that nipple right in. Than your 5/16 sap tubing
goes right on. I made a 8" wide tray with 1/2" lips on each end that runs full
lenght of my hood to catch condensation dripping down from my preheater.
The lips at each end of my tray catch the condensation rib on the inside of my hood. I also had a issue with the steam going up the stack, so i installed
a large squirrel cage fan in my steam system (works great).

[DavyJones]

One question I have for you or anyone else who built their evap. with an angle iron frame....
Sean

Sean, Thanks.. My 2x3 pan probably weighs about 20 pounds if not more when it's empty. Add a couple of gallons of sap and add 15+ more pounds. The pan's not going anywhere even empty. I cut some strips of that 1" insulation blanket to use as a gasket. It won't slide around I would not worry about changing the angle iron to keep it in place.



David

[DavyJones]

Davy,
You can pick up a brass nipple at your local hardware store, 1/4" pipe thread on one end and 5/16 hose barb on the other.... (works great).

Smitty, Thanks! I was wondering what I was going to get. So your gutter inside is 1/2" x 1/2" The picture I did I have it 1/2" wide by 1/4" high but It's should be easy enough to change. I gave my drawing to my friend last night and I think he said bending that 1/4" might be a little difficult on his equipment and he might make it a bit bigger, I told him ok. How did you attach your squirrel fan? Did you put it inline with your stack? Any pictures of how you have that hooked up would be great.

Thanks
David

[Smitty]

Davy,
My hoods have 1/2" x1/2" Channels for condensation. My back pan (2'x4') has
2 8" duct pipes that rise about 2', merge into a single 10" pipe, 90* and go through the wall into my wood shed,than it ties into the squirrel cage, and than
goes through the roof. Very importantly, the fan is belt drive(some fans have motors built in) so the condensate does not smoke the motor.In the tops of my hoods,were the duct pipes set, i welded collars in and inserted nipples with hose attached that run down into my condesation channels on the hood to catch the condensate from the steam pipes as well. I am still trying
to figure this chat forum thing out (bare with me). Iwill send pictures when i figure out how to do it.

[SeanD]

I cut some strips of that 1" insulation blanket to use as a gasket.



David

Thanks everyone for the feedback. David, you answered another part of my question with the gasket. Sounds like the weight of the pan plus about an inch of blanket makes an air smoke tight seal.

I wasn't originally planning on building an evaporator, yet. I was just hoping to put some dividers and nipples on my stainless flat pan. But hearing how tricky welding with stainless can be, maybe I should work with a bunch with straight steel first.

I hope to get far enough in the class to have such concerns. I'll probably just end up with a grate that looks like a kindergartener's art project.

Sean

[Smitty]

Smitty, Thanks! I was wondering what I was going to get. So your gutter inside is 1/2" x 1/2" The picture I did I have it 1/2" wide by 1/4" high but It's should be easy enough to change. I gave my drawing to my friend last night and I think he said bending that 1/4" might be a little difficult on his equipment and he might make it a bit bigger, I told him ok. How did you attach your squirrel fan? Did you put it inline with your stack? Any pictures of how you have that hooked up would be great.

Thanks
David
DavyJones,
I did not get a chance to put my pics on yet,802maple(very smart man)
has influenced me enough to build an air injection draft system. its been keeping
me busy(between all the other stuff i am trying to get ready). Ihope to get the
pics on here sunday nite. I did not forget.

[DavyJones]

My friend had me pick up the hood he made from the plans I drew up. I'll have to say it was impressive and big. I thought at first to big but after installing it and firing up the evaporator today I am glad it is oversized. I was able to keep it elevated off my pan about 6" or close to it without having steam leaking out the sides. A little steam does escape when you walk past and create a little breeze but nothing to really even consider. A cigarette in burning in an ashtray probably puts off more smoke....

Initially I thought I was going to have to solder the sides on but they said it was easy enough for them to put them on with a Pittsburgh seam. It looks like a seam how you put a regular piece of duct together. How they did they I'm not sure but it's nice. The entire thing cost me $125 for the metal and him to put it all together for me. I have is suspended by some wire from 4 eye hooks I put in the top at each corner. The cable is a little thin but it works. I can't lift it by myself by the cable alone. I have to have my son grab one end of the hood while I grab the other end and then we can lift it and I can hook the cable onto a nail I have on the wall. If I can pick up a winch at a garage sale or something I'll probably mount that on the wall to make it a one man job until then it's not bad you're not lifting it up and down all the time so I can live with the 2 person method for now.

Here are a couple of pictures. The first one was just when the sap was about to start to boil and the second one was when it was boiling pretty good and allot of steam was coming off.

You can check out the rest of the pictures at our web site thebittners.net (http://www.jonzilla.com/thebittners/dispphotos.asp?path=pictures/2009\Maple Syrup Season/)

http://www.jonzilla.com/thebittners/pictures/2009/Maple%20Syrup%20Season/100_744709.jpg http://www.jonzilla.com/thebittners/pictures/2009/Maple%20Syrup%20Season/100_744911.jpg

[Haynes Forest Products]

Nice job I like the cross bending it sure looks cool. Oh on the seams power tools its always about the tools. If anyone wants to know about radiant heat you will notice the young lad falling asleep in front of his arch his back is cold and his knees are ready to catch fire thats radiant heat at its best.