Arch Design

[NW Ohio]

9645I visited several sugarhouses and talked to different people about their pans and arches before we bought/built our own. I talked to people about raised and drop flues, thinking that I preferred drop until I heard about the damage firewood did to the front of the flues. I really didn't want raised flues because of the extra float, I figured that as a hobby we would be better off if we kept it simple. The picture that I included is what we came up with. We bought a 2x4 Smoky Lake with drop flues and built an arch with a cast refractory cement shelf. The heat leaves the fire box goes back/up the ramp under the syrup end of the pan, travels through the flues then up the chimney.

I am posting this because I wonder if anyone else has an arch like this. We are pretty happy with it for a couple of reasons: 1) we can't hit the flues with fire wood, 2) the length of our wood doesn't really matter (there is about 5 feet of length going up the ramp that could accept wood, although we try to keep it in the fire box, off the ramp), 3) we were usually around 20 gph.

For next year we are thinking about taking the top row of full bricks out and replacing them with splits. As it is right now the wall of the arch is about 4 1/2" (full brick + K-FAC). The problem is that the brick is right up against the sides of the outside flues, so we feel we are losing surface area that could be improving our evaporation rate.

Any thoughts?

[Bernie/MA]

Inovative things interest me. I think you were brave to build this not knowing if it would work having never seen one. I don't quite understand where the bricks are. Under the pan on the shelf? Also, what's holding the shelf up? Being next to the stack and the open door loading wood must get pretty hot. I'm curious, when you start boiling what areas get hot first? You may have hit on a really good idea. I'm a retiredwelder/fabber and I've built a lot of diffrent things, including evaporators.

[NW Ohio]

Some might say brave, others would call it something else... The truth is if it didn't work I figured I could "reconfigure" to a more traditional arch easy enough.

The lower portion of the arch is bricked as usual. Above the door though, and extending towards the "back" of the arch, one of the rows of bricks is replaced with the shelf. Above the shelf (sitting on the shelf) the bricks continue to the top of the arch (~6 inches above the shelf). The flues fit between the two sides of the arch a little to snug and take away from the surface area that gets heated from below. It actually doesn't get too hot around the arch. I read about arches that you couldn't stand next to too long because of the heat. We didn't want that, which is how the walls of the arch ended up 4 1/2" thick (K-FAC and brick). The outside actually stays cool for quite some time into the boils. The base stack is 1/8" steel which is lined on the inside with ceramic. It will get hot enough you don't want to hold your hand on it but incidental contact isn't going to cause a burn. The door gets hot. In fact it will glow. We used a Barrel Stove door so it is the only part of the arch that gets super hot. We might have to change that but figured this would work the first go-'round. We didn't have a blower but used a fan and left the ash door open (poor-man's AUF). 9666 9667 9668 9669 9670

The boil starts at the front (syrup side) of the flues and it stays the hottest there throughout the boil, sometimes splashing over the sides of the pan in that area. Although the boil spreads across the whole flue pan (actually seems to intensify at the back (stack/door end), it does almost look like the boil roles across that part of the pan, front to back (not sure how better to describe it). The heat still hits the bottom of the syrup pans first.