Just wondering out loud, here - are those grates too close together? Just looks like limited air flow between each grate. I could be wrong - it happens a lot...
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Just wondering out loud, here - are those grates too close together? Just looks like limited air flow between each grate. I could be wrong - it happens a lot...
The spacing and arrangement look perfect! Nicely built.
The only comment I have is it looks like the grates and firebox are very long. If they are much longer than 20 inches you are going to have a hard time keeping wood over the whole area and if there is an empty area, draft air will bypass the fire and cool your flues. Even if you keep it filled it is really not the most efficient setup.
If you can figure a way to shorten up the firebox and raise the arch floor under the drip flues you will be way ahead.
Grates are 30", i was trying to figure out how to end it shorter, but figured if i left a gap at the end it would be hard to close off. I guess i could cut it off shorter, and then weld flat plate from the top of the grate down to the floor of the arch.Quote:
Originally Posted by RileySugarbush
Or... I could just leave it that length and weld the flat plate blocker on the underside at around 20", that way as the fire burns down i can push some of the old coals up under the front pan (8" below), but the air will be coming up through the grates in the 20" or so closest to the door?Quote:
Originally Posted by striker3636
At this point, a good possibility would be to cover the back 10 or 12 inches of grate with bricks. Stack them right up to within an inch of your flues, and face the side towards teh fire and the top with firebrick splits.
That would get you where you want to be, with a reasonable sized firebox, and good grate and the flue gasses going up through your drop flues.
So, I have a couple more questions that I thought I would add on to this post since it already has some pics of my setup.
I tapped 100 trees on the weekend, and although a little slow right now, probably half the trees are running. I collected maybe around 8-10 gallons of sap yesterday. Looking at the weather, hovering around freezing or very slightly above for the next little while, I doubt I will be seeing any major flows for a bit, so I hope to try out the new evaporator when I get to maybe 30 or 40 gallons. This isnt an awful lot, it takes a fair amount of sap just to fill the flues, so I'm wondering how to manage the three pans after an hour or two of boiling when the level gets low and I don't have enough sap to add. Should I dump the whole works from all three down into one pan and continue that way? (I have some flat steel plates that would allow me to take off one or two of the pans and replace with a plate). If I do this, should I put it all into one of the flue pans, or the flat pan? If I do it all into one of the flue pans, I assume I need to stop when level gets down close to the top of the flues (bottom of the pan) and finish in the flat or over a propane finisher?
Also, since my last post I've welded up some mods to the evaporator and brought it up to 8" stovepipe, and added some more air intake to the door awaiting a suitable blower, I'll post some pics when I get a chance.
Thanks for any assistance, still trying to get this figured out.
A new evaporator will take some getting used to. Just make sure you don't run out of sap with a raging fire going and you will be okay. Also, have some water on hand in case of emergencies.
Ditto on the previous comment about stacking bricks up under the flues to within 1 inch. You want to force the heat through the flues to make it boil properly. You could maybe make a ramp out of the bricks (just dry-stack them) to help force the fire up into the flues and cover up some of the back of the grate area. Personally, I would use 16" wood for that size evaporator. Using onger wood and a longer firebox just seems to waste wood as lots of flame goes up the stack.
I would boil until I was almost out of sap and then stop firing and leave the contents of the pan until I had more fresh sap to boil (this is called sweetening the pans). As long as the raw sap has been brought to a boil, it will kill any bacteria in the sap and it will keep for several days (longer if cold temps).
If you are itching for some fresh syrup, you could combine some pans and just run water in one (or put in the metal plate) and boil some more until you have reduced the volume to something manageable to bring inside and finish on the kitchen stove.
In general, you should never finish syrup in a flue pan, so I would keep the more dense syrup in the flat pan and eliminate one of the flat pans.
For the record, I run with about 1" of sap over the tops of the flues and run about 2" deep in a flat pan.
I use 21" wood on my 3x8. Look at std evaporators, a wall and a ramp to the flues is needed for efficiency of burn. My flues are only 1/4 above the surface, forcing the heat into the flues.