Oddmott
03-26-2014, 10:34 AM
Well, i found there's a bit of a blackhole out there for viable examples, descriptions and plans for building one's own evaporator. It was really frustrating as we set about building our own late in 2013 with no experience or idea of where to begin.
Figured i'd post some pics of our finished project here to add a little bit of content for someone else who may be facing the same frustrations. Unfortunately, i live/work 2 hrs away from our sugar bush and where the boiler was constructed, so i don't have a ton of pics of it being manufactured, sorry, but i'm trying to get some from my bro.
9462
9463
Essentially, we found 2 old wood furnaces in good condition and of similar size. We chopped off the tops and the heat exchangers. We used the best one for the firebox and the worst one to extend said firebox an extra 1'. Furnaces were free.
We had to buy one 4x8 sheet of 1/4" metal for general reinforcement and manufacturing the back 1/3rd of the build.
We lined the interior with 9"x4.5"x1.5" refractory (fire) bricks (54) and two 16"x16"x2" cement pads and one 24"x24"x2 cement pad. We use the cement pads to line the bottom and rear slope as they are cheap and stand up to getting hit with logs better than the fire bricks. They also insulate fairly well. They have to be replaced after 2 seasons though.
There is a significant 3" baffle between the firebox and the ramp up to the rear chamber. It helps keep quite a bit of the flame under the primary pan, but honestly, when you get a good fire roaring and maintain it, there is more than enough heat to have the secondary pan boiling hard too.
We had designed the boiler for a taller primary pan we were supposed to get for free, but it was too damaged and repairs would cost nearly as much as we paid to have a new one made. So that's why you see the warming/secondary pan sitting oddly high.
We did a test boil and cured our new pan last weekend. It was -20C (-4F) and the stove was stone cold. It took 1 hr 18 minutes and we had 5 gallons of water boiling in the secondary pan and 10 gallons boiling in the primary pan. Not bad.
If you know how to cut and weld steel... you can build this thing for pretty much $400. Unfortunately my high school shop class welding skills were a little sub-par so we needed to pay my buddy to do it. For metal, oxygen, welding rod....i think it's costing us about $550 CDN for everything.
Figured i'd post some pics of our finished project here to add a little bit of content for someone else who may be facing the same frustrations. Unfortunately, i live/work 2 hrs away from our sugar bush and where the boiler was constructed, so i don't have a ton of pics of it being manufactured, sorry, but i'm trying to get some from my bro.
9462
9463
Essentially, we found 2 old wood furnaces in good condition and of similar size. We chopped off the tops and the heat exchangers. We used the best one for the firebox and the worst one to extend said firebox an extra 1'. Furnaces were free.
We had to buy one 4x8 sheet of 1/4" metal for general reinforcement and manufacturing the back 1/3rd of the build.
We lined the interior with 9"x4.5"x1.5" refractory (fire) bricks (54) and two 16"x16"x2" cement pads and one 24"x24"x2 cement pad. We use the cement pads to line the bottom and rear slope as they are cheap and stand up to getting hit with logs better than the fire bricks. They also insulate fairly well. They have to be replaced after 2 seasons though.
There is a significant 3" baffle between the firebox and the ramp up to the rear chamber. It helps keep quite a bit of the flame under the primary pan, but honestly, when you get a good fire roaring and maintain it, there is more than enough heat to have the secondary pan boiling hard too.
We had designed the boiler for a taller primary pan we were supposed to get for free, but it was too damaged and repairs would cost nearly as much as we paid to have a new one made. So that's why you see the warming/secondary pan sitting oddly high.
We did a test boil and cured our new pan last weekend. It was -20C (-4F) and the stove was stone cold. It took 1 hr 18 minutes and we had 5 gallons of water boiling in the secondary pan and 10 gallons boiling in the primary pan. Not bad.
If you know how to cut and weld steel... you can build this thing for pretty much $400. Unfortunately my high school shop class welding skills were a little sub-par so we needed to pay my buddy to do it. For metal, oxygen, welding rod....i think it's costing us about $550 CDN for everything.