Curled evaporator top

[ahowes]

So that I don't hi-jack Matt's run thread anymore, here's a new thread :)

In case you missed it in the other thread, my evap top curled up big time. The obvious fix is to weld structural verticals to the horizontal surface, either above or below. The problem is that my welding neighbor is out of town on a business trip all week. I'm thinking of taking the top off and taking it to the local fab shop, but I'm scared to think what it might cost. So far, the entire setup has only cost me about $190, including the pans. I'd hate to go and blow two or three hundred on this fix.
The alternative though, is to maybe do some permanent damage to the top - it might not straighten out after the next boil. I've got to admit that the curl, lost heat out the sides, and the unlevel pans took a lot of the fun out of my much-anticipated first burn.

Do you think 10 concrete blocks stacked on each end will keep it from curling? There is enough flat surface to do that. I don't know how strong the curling force is.

OldGuy-the warp around the pans wasn't so much the problem as the curl over the entire 6 foot length of the top. I had a 3 inch gap in the front (between the top and the block/insulation/firebrick vertical sides and front. It also raised about 2 inches in the back, which caused even more draft to avoid the intended flow path (past the back pans and up the flue).

I'll figure it out (I'm not the kind to quit), but any suggestions would be great. Hope you all have a good run today - before and after the Super Bowl, of course.

[Sugarmaker]

ahowes,
Not sure what is going on with your pan but doesnt sound good!
A picture would help.
Regards,
Chris

[ahowes]

No, not the pan - it's the top of the evaporator that my pans sit on. It is 4'x6' and curled the entire length of the top. It's straight now, since it cooled.
The design is a simple concrete block "U" with arch board inside the blocks, then firebrick inside that. The firebox is about 2x2x2 and then the back four feet of the box is elevated to within a couple of inches of the pans. The flue comes up out of the top near the back (of course). The front of the top lifted up 3 inches and the back near the flue lifted about 2 inches. I think the stainless is 5/16" thick (not sure), but it is pretty durn heavy.

I've been down with strep all weekend, so haven't been out to take a picture. The obvious long-term fix is structural stainless welded on to give a vertical support that would resist the warp, but maybe a bunch of weight on each end would get me through...

Thanks.

[whalems]

try and protect the steel with insulation. it may help but pictures would help us understand better what you have going on.

[C.Wilcox]

Sounds like the heat is getting to the rails that support your pans? If that's the case the only thing you can do is insulate them to keep them from getting so hot. You could try cutting strips of ceramic blankent wide enough to cover your rails. That would help keep them from getting so hot.

[Haynes Forest Products]

What purpose does the rail serve? if you have a block ARCH the EVAPORATOR can sit directly on it. What is the rail made of. If its any kind of angle or C channel its going to curl up every time. Unless its tied into the blocks and I dont mean little strips of flat stock jammed into the cracks.

I have I beams that with a small amount of heat will curl up like a banana.

[ahowes]

Sorry not to have posted pics, but after I got to feeling better, I had to go back on the road for a couple of meetings.
The inside measurement of my firebox is about 4 inches wider than my pans. I have blocks/archboard/firebricks. The stainless top (5/16) goes from the outer edge of the blocks to two inches inside the firebrick; thus only two inches are over the fire, plus the rail in between the steam trays. I can easily insulate that with more archboard. The archboard will not be in contact with anything but flames, the wood won't hit it.
I am going to order the extra archboard tomorrow morning and I think it might do the trick. I probably won't receive it until Tuesday or Wednesday unless I pay for fast shipping. Thanks for the input.

[Sugarmaker]

Sounds like a flat stainless steel strip or strips along the edge of the block arch, and between the pans.
Yes I could see how these might warp due to the heat.
Chris