Vid of my homemade evaporator in action

[Loun]

I am probably doing a lot of things wrong :) but this is what I spent 7 hours doing Saturday

Video Link:
http://vids.myspace.com/index.cfm?fuseaction=vids.individual&videoid=&release=104038555

Boiled 45-50 gallons in that 7 hour period. 2 hours of it was very little boiling as the wood that I bought wasnt seasoned as it was supposed to be... so I was using the shop vac to start the combustion process. I need to move the pan back on the arch as the front half of the pan wasnt getting as much heat as it needed to. A lot was wasted, as evident at night by the jet turbine like flame shooting out of the chimney pipe.

comments, suggestions?

-Lou

[RileySugarbush]

Looks great, wish sap was running here!

A couple of comments that may speed things up:

The wood could be split finer.

Try blocking off the top 3/4 of the front and blowing the air in under the grate. That will cut down on the cold air running over the fire and under the pans. That may be why the front of the pan wasn't boiling well.

is the firebox the whole length? If so, stop it after about 20" and build up the rest to within a couple of inches of the pan.

Make sure any condensate on the bottom of your preheater isn't dripping into your main pan!

Good luck and have fun!

[Loun]

Very good points! The firebox is 18 - 20 inches deep then its a metal arch that raises up to about 4-5 inches below the pan. The real heat didnt really seem to be starting until halfway through the pan. I am going to shift the pan back some regardless, this is possibly because of not having the top portion or the front blocked off as you mentioned.

I moved the preheater backwards so the edge was on the pan allowing full steam off, and capturing some of the wasted heat better, it preheated better than the steam, there was that much heat being wasted at the back of the arch. theres a good 15-18 inches of arch in the back not being used for anything otherwise.

I will heed your advice with splitting smaller, I was actually splitting all the wood I was starting with smaller but then when I was mixing the dry wood i had and using the shop vac size wasnt as much of an issue for combustion.

thanks! Definitely have some work to do, id like to try to tighten up some spots so its closer to air tight.

[wegnerwelding]

Look pretty sweet Lou!! I'll be doing the same in a couple weeks. BTW is that your TT doing the burnout?

[BarrelBoiler]

couldn't see your video (dialup didn't want to wait) trying to remember the pics from before
how high is the firebox - bottom of the pan to the grate? could be yuor fire is to low -- from your discription you got a boil where the slope started getting close to the pan i'd try getting the fire closer to the pan and also makeing the exit a little closer maybe 3inches below the pan
if i was tweeking that's what i'd check
good luck

[RileySugarbush]

Oh now I remember your description of the arch from an earlier post. That 4 to 5"space under your pan is really too big.

I like to try and keep the cross section area of the flue about constant from the back of the firebox to the top of the stack. With your stack, which looks to be about 6" diameter, has an area of about 28 sq inches. If you close up the gap under the pan to about 1.5 inches it will still be a bigger area than your stack and you will get much better heat transfer.

[Greg Morin]

try setting more blocks along the sides of your pan to protect it from the wind it made a huge difference on mine

[SeanD]

Hey John,

I remember you giving me similar advice when I had issues with my back pan not boiling. I think part of my problem then was also stack size and height, but the trouble I'm foreseeing again this year is that I have to vent the stack out the back like Lou, so I need 8" for the stack to fit in between the top of the arch and the bottom of the pan. Should I bring the arch within a couple inches of the pan most of the way and then drop down for the pipe at the end?

Next year, I'm going with a base stack.

Sean

[BarrelBoiler]

yup that is just what you do---slope 'er up and slope 'er down to the stack and may be even pile som stuff in the back corners to keep the heat up near the pan also some put a baffle of some sort in front of the stack hole to take away the direct route up teh flue

[RileySugarbush]

I agree with Boiler. Do what you can to keep the flow up by the pans but make some sort of transition to the stack opening.

[Loun]

sorry was MIA for a couple days. Andy, thats my 01 TT at a local bike event. Thanks again for making up my pan. Hopefully im doing it some justice :) If anyone needs stainless, you wont deal with a nicer guy that Andy over at Wegners.

I want to setup a wind break in general and definitely trying to the protect the sides some is a great idea. My wood was wet since the guy I bought it from lied about it being seasoned so I was actually putting wood against the pan to try to dry it out a little bit.

Boiler and Rileys I think you are right, I set it up to efficiently flow the air which actually very efficiently flows the heat as well lol. I will take a look and see what I can do to alter that a little bit making the heat stay in the box and work for me just a little bit longer. with the setup I have it would be hard for me to raise the arch up but will see what I can make happen.

I cant wait to get a real arch someday :) I also and a stickler for efficiency so I bought a digital refractometer to measure the sugar content and try to find some different ways to increase % to hopefully end up being more efficient even before boiling.

Thanks again for all the help guys, I really appreciate it.

-Lou

[BarrelBoiler]

loun
run the video nice job on the setup went back and looked at the build pics too
as you know when you ask for suggestions on here they come out of the woodwork like relitives at a millionaires funeral--- ssssoooo:) IMHO i'd

add another birck under the grate (where did you get that anyway) so you have more space for the blower and under fire air

figure out a way to set/hang your door so its closer to the arch and blocking off the heat escape at the top, make the bottom even with the bottom of the grate leaving your self a draft slot that can be closed and opened by use some loose bricks

as far as squeezing the heat toward the pan, did you stay with the window well idea? is it just in the back or covered with firebrick? can you add another layer of brick to bring it up closer to the pan? where its level crushed stone will work to bring things up.

some of the folks on here like to get the gases/heat swrilling by setting bricks slightly higher than the level area headed for the stack the draft will take the shorrtest route out so by baffleing you can spread out the heat

good luck and have fun it is always an "aahhaa" moment when things really start rolling even at 7gph