arch dimensions

[darkmachine]

My friends and I are building a 6 x 10 arch, I have recently aquired the cast Iron clean out doors, and base where the stack attaches. My question is, what diameter stack I should use, and how tall should it be? The measurements I have for the arch came from one that has "Grimm lightning" on the front on each side of the doors. But the arch didn't have a stack to measure. Any suggestions would be great! We have to get this one build before this season :)

[3rdgen.maple]

Wow 6x10 I hope you are adding alot more taps. The general rule of thumb is twice as long as the length for stack height.

[PerryW]

6x10 seems like an odd size. Usually evaporators are at least twice as long as they are wide.

But anyway....

my old 2x6 had an 8" x 12 foot stack, my 3x10 has a 15" x 20' stack. I'd say you'd need at least 16" or 18" dia x 20' long.

[darkmachine]

I was in a hurry, lol, the steam away that i dont' have yet, is 6x10 the syrup pan is 6x6, sorry about that. This season i am using two syrup pans, and a metal plate to cover up the back of the arch.

Jake

[SilverLeaf]

I don't mean to hijack this thread with my ignorance, but what exactly effect on the fire does the stack length have? I know the general rule of thumb, as mentioned here, is 2x the length of the evaporator. But why? :confused:

I'm building my first evap now to replace my old "firepit and stovetop" method, and so like you, darkmachine, will have to size the stack appropriately. But I'm missing an understanding of how the stack size helps (or hurts) the fire inside the firebox... Perry? 3rdgen? Can either of you experts enlighten me?

[3rdgen.maple]

Now Im really confused.........darkmachine
Silverleaf the stack length is what draws the proper amount of draft through the arch. The longer the arch the higher you need it in the air to get the proper flow of air.

[SilverLeaf]

So, just by adding length to the stack, that automatically pulls more air through the arch? Why is that? Is it because the smoke and hot gasses have to escape somehow, and the farther away they have to go to escape the faster they rush to get there?

[SilverLeaf]

darkmachine - how'd you come up with the 6'x6' pan? are you laying two 3'x6' pans cross-ways on your arch, and then laying a 4'x6' metal plate on the back of your arch where you don't have a pan yet?

[darkmachine]

This might clear up some things.

Here is a pictures of the cast parts that I have so far
http://images.darkmachine.multiply.com/image/2/photos/16/400x400/4/102-3978.JPG?et=zr2fa3aeu8OyT7hmScIDqw&nmid=286067603

Here is picture of the two syrup pans I plan on using this season, joining them together with fittings to effectively make one pan. That will leave about 4 feet at the back of my arch between the pans and the stack that I need to cover with a metal plate.
http://images.darkmachine.multiply.com/image/2/photos/16/400x400/5/102-3979.JPG?et=K51D4iA0tkTODuONYImLFg&nmid=286067603

Thanks for the sizing info on the stack, Just wanted to make sure it would draft properly and not be restricted by the diameter of the flue. So by using the 2 x length of Arch, that would make my stack hight 32 feet? Or would twenty be ok? I'll have to attach wires to keep it from blowing down.

Still just starting out, when we can afford a flu pan we'll replace the second syrup pan, and use it for a backup.

[PerryW]

It looks like you have two front pans from a large evaporator; probably a 6 x 16'.

Each pan looks 6' wide and 4' long.

I supposed you can build a 6' by 8' arch and make some syrup, but it is uncommon to have such a wide evaporator for only 8 feet of length.
Usually a 6 foot wide evaporator would be 16-18 feet long.

[darkmachine]

The pans did come from an evaporator that size, we are going to build an arch that should accomodate one of these pans and a 6 x 10 flue pan. Until we can afford the flue pan though, the plate and the two pans will have to work. They will be worlds above what we used last season.

[danno]

no problem cabling the stack - that's what many of us do to keep that thing from tumbling down.

[3rdgen.maple]

darkmachine 20 foot stack is good, how many taps are you looking to put on that rig once you get the flue pan?

Silverleaf your explanation sounds bought right on the gasses sounds good to me,but honestly I never really thought about it just going by the rule of thumb.

[darkmachine]

This year will be a transitional year, actually we might have a few, before the flue pan. Our plan is to put out 400 or so buckets this year, and the rest on short gravity lines at collection points,we are figuring between 500 and 800 this year, depending on the tree leases we can get. Once we get the back pan hopefully we can work our way up into the thousand tap range, shifting to mostly tubing before we have to purchase an RO. Machines this size are monsters I know, and someone who ran one told us he rememberd putting 50 cords of wood into an evaporator this size. Not to mention the amount of sap you need to keep it to keep from burning it up.

[3rdgen.maple]

That is awesome. GO man GO