Arch build, what thickness/type angle for frame ?

[smokeyamber]

Did some searching on the site, but couldn't find a recommendation. Planning a small arch build to replace the barrel. Not sure what size/thickness for framework. Since it would be lined with firebrick, can it be a bit less thick ? Cheapest solution is recycled bed frames :lol:Also looking for a door solution, currently scoping our old wood stoves or possible the tried and true barrel stove door...

Also wonderiing on skinning the arch with galv sheet instead of stainless... any issues other than it will eventually rust ?
:confused:
Arch would be a 2x4 to 2x6 depending on how much my shack can be expanded. :)

[RileySugarbush]

I built mine with 1.25 x .125 angle. Even a little smaller than typical bed frame stock. More than strong enough. I skinned it all with 16 gage carbon steel, painted black. With proper insulation, the paint holds up fine. I used firebrick splits and arch board in the firebox, and ceramic blanket elsewhere.
I welded the frame and attached the skins with self tapping sheet metal screws. Simple.

Front is 12 ga and the door is home made and airtight.


http://www.mapletrader.com/community/attachment.php?attachmentid=3534&stc=1&d=1304541831

There are some photos here:

http://gallery.me.com/jabushey#100085&bgcolor=black&view=grid

[jrthe3]

i used 2x2 1/4 inch angle i skined mine with 28 ga galv. sheet metal it ben going for four seasons an still good

[smokeyamber]

Thanks ! Sounds like the bedframes win! I have them along with the galv sheetmetal. Looks like the door will be hardest part.

One other question. I was planning on building the pan's first then the arch to make sure as I built the arch the pans fit well ( may try the drop flue with copper pipes on it per your build a while back Riley :D )

I can also size as I build to use mainly full firebricks and minimize my cuting and fitting this way as well.

One last design question, I was thinking of making the rear flue collar come out the back instead of the top of the arch, it would give me a bit more boiling surface and since my chimney goes out the side wall and not through the roof that's how the current arch works. Do you have any input on how this affects the performance on an arch ?

Thanks again for the great info, I would not be building this in my 4th season of boiling without all the great info you guys have supplied !

[3rdgen.maple]

The only thing I would change on that diagram is put a ramp in it instead of the flat vertical wall at the back of the firebox. THis would allow an easy transfer of the heat up under the back pans.

[RileySugarbush]

Smokeyamber,

If you want to try the copper drop tubes, you need to check out what Bill Warner ( Warners Point) did with that design. He stopped out here and talked a bit and then went and made a super 2x6 with it that really works great. I think he was getting 40gph out of it. Look for some of his posts of contact him for details. As far as the stack exit, I think it will work OK as long as your were going out horizontal anyway. I've seen some that have cold corners in the back of the flue pan. Maybe a wide transition to round would help that, like most vertical stack bases are.

3rdgen,


I've heard both sides of the ramp/vertical firebox argument. I went vertical on mine for several reasons:


I had forced draft, so the flow restriction was less of an issue than on traditional arches.

I wanted the flue gases to get up to the bottom of my pans as quickly as I could after the fire.

It gives a good location for my AOF manifold. along the back of the firebox.

I gives lots of room under the arch for my blower assemble with noise control and inlet damper box

It is easy to build and brick, with all right angles.

The results have been fantastic, with evaporation rates rivaling any 2x6 I have heard of, even with the short flue pan.

[warners point]

The guy that built my arch used what ever angle iron he had laying around. Mostly 3" that had come out of old fireplaces The back of my firebox is also vertical and I had absolutely no problems getting the entire flue pan to have a raging, even, consistent boil. I have to agree with riley, that you want to have a square to round base stack the entire width of your evaporator to get even heat on the flue pan.

[smokeyamber]

Thanks for the added information, I will likely have a square back since I like to keep things simple. Drop tubes may happen as well since I have a limit on the shack so the evap will be around a 2x5ish...drop flues will give me more boil for less length:)

I was going to connect the flue to the syrup pan with 3/4 fittings, is this big enough ? I have seen everything from 1/2 to 2inch mentioned here. Also the syrup pan may be kinda small 2x2:confused:, what is the smallest you can have dividers in ?


Can't wait to get this built for next season and this site is awesome for us diy'ers !

[warners point]

On my 2x6 I have 3/4" connecting pipes and my syrup pan is 2x2 with three 8" channels. I didn't have any problems with gradient when it came to drawing off syrup.

[fishman]

I used 1 1/4 x 1 1/4 x 1/8 inch angle and skinned it with 20 ga. steel pop riveted on. Painted it with black heat resistant paint. Got the plans on here. Works great.

[smokeyamber]

Thanks for the info fishman and warnerspoint I will go with the 3/4 connections, I will also be doing the drop flue with tubes so the 2x2 sap and 2x3ish flue pan will likely be my setup. What kind of boil rates do you get on your setup warners point ? My goal is 10-15gph. Higher would be nice since I will likely expand to more than 50 taps.

More I read on this site the more I get hooked on this whole thing, Next I will be needing to find people to actually PAY for the syrup instead of giving it all away :lol:

[RileySugarbush]

Smokey,

If you put a good number of the drop tubes in your 3' pan and add a small under fire blower you will get at least 25 gph.