Terms of the trade

[Helicopter Seeds]

Hello, I have been reading this site for some time now, and yes I am hooked.
last year (2014) I tapped my single maple tree, boiled the sap in my back yard using free firewood fromthe dump, open fire and a turkey fryer pot. I got 3 quarts of syrup. Not counting labor - it is a hobby, I only spent 13 dollars on some taps and lines.


So this year, I am growing. Neighbors trees, my in-laws trees, I expect 25 taps. I bought some 700 leftover second hand bricks and 3 steam tray pans, plus a pickup truck! so my investment is higher. More give-aways expected, but maybe I can sell some to break even.

Anyway, I see some terms that I am becoming used to, and others I have no Idea about. Why do they call it an "arch". does not look like an arch in shape. But I suppose mine is a brick-block arch. I suppose also it is close to a 2x3 in size.

What does AOF/ AUF mean? by context, I presume it is airflow terms.

BTW, I also made butternut tree syrup - tasted just like maple, but did not produce nearly as much, and it had the jelly stuff - pectin - that had to be strained. Not sure if I will bother with that one again.

[Potters3]

Air over fire = Blowing air over wood to get a cleaner/hotter burn
Air under fire = blowing air under the grates up thru the wood

[maple flats]

I also can't find the origin of the name "arch", I googled it but only got a definition, not the origin. Potters3 is correct, but AOF (air over fire) is little more that that. The AOF blows down into the fire with a high pressure blower to mix in more oxygen for more complete combustion. Doing that gives you more heat under the pans and less wasted in or above the stack. That means faster boil using less wood. AOF will not likely be feasible for you until your addiction grows bigger.

[markct]

If i had to guess i would say the original stone fireboxes likely had an arch topped opening in the front as many fireplaces and other stone structures did. The name likely just stuck despite changes thru the years. Just like a car dashboard no longer prevents mud from entering the passenger compartment when a horse goes into a high speed dash as it originaly did

[Urban Sugarmaker]

Regarding the term "arch". According to [I]Backyard Sugarin'[I] by Rink Mann, fire boxes are built up in the rear toward the stack to force the flames to "arch" upward and stay close to the bottom of the pan along its entire length. This helps transfer as much heat as possible to the pan. In a block arch this could be done with sand or bricks. Commercially made arches are designed this way to accomplish the same thing.

[Helicopter Seeds]

Thanks all. Glad I asked, as the air source was on my mind.

I was actually contemplating rigging a natural draft AOF out of scrap square tubes, ~2 x 2. I have seen a lot of vids out there on gasifier stoves, rocket stoves, and if I do some welding (need to get my torch fixed first) I can route fresh air through the tubes, used as a grate, then turn them back up higher right under the pan. Old fashioned wood cook stoves have two air vents, one for primary and one for secondary, so now I see that is what AOF and AUF really mean, with or without power venting. Otherwise, I will actually use a brick front with the gaps being the air source. I'll post pics when done.

[Super Sapper]

Just remember to have at least as much of an opening for intake air as you have in your stack. This is not the same as running a wood stove.