How big of a firebox is optimal? 2x4 pan

[Loun]

The girlfriend and built our cinder block arch a few times today lol. My plans called for 4 blocks wide 4x8" as I was building it I decided I wanted it 6x8" wide. I built the whole thing and decided the firebox would be too big. 4x8"-6" (for fire bricks) = 26"w x 30"l" 24"h fire box. I decided I wanted to make it narrower since my pan is only 24" wide. So I went 5x8" wide to make a firebox that is 3x8"-6"= 18"w x 30l x 24"h firebox. Since my pan is 24" wide I left the top row of fire bricks off so the heat will get up to the outside of the pan.

I dont have the pics yet so here is a diagram... will the 18wx30lx24h firebox be big enough?
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| |..............| |
|--|--|---|--|--|

Pics coming soon!

-Lou

[Loun]

I uploaded some pics the arch piece has to but shortened and bent, it will be up against the back of the "firebox" and will be shorter heightwise to allow for a more gradual rise, like in the second pic.

Hows it look so far? Chimney will be 6 inch and will be right above the metal arch piece.

http://www.flickr.com/photos/91684118@N00/

Thoughts, suggestions, and recommendations?

[KenWP]

Actually looks good. Are you going to have a grate so you can bring the fire up close to the pan. You would need a pretty good fire to fill that space and heat a pan unless you put a grate or raise up the floor.

[Loun]

i was at home depot trying to find something to use as a pan and wasnt having any luck. Someone said they might have access to a drainage grate so im waiting to see on that. If that works out I will put it on 4 bricks so it would probably raise up about 6 inches closer to the bottom of the pan. I want to find a way to add some extra air in with a blower so im working on that part now. Chimney was setup and looks like it will work well too. I think its 8ft tall ninety on the top and will be tied off to something above to hold it up.

Thanks for the compliments. im going to have a small angle iron frame on the bottom of the pan will overlap maybe .5 inch on either side so the frame will help a ton to support it.

[TapME]

looks good Lou, your almost there and you have got this figured out pretty well. Have fun

[C.Wilcox]

Looks sharp Loun! Should work really well for you.

[3rdgen.maple]

Looks good lou, funny how much fun we can have just building the arch. One suggestion would be to fill the holes in the block with some sand to help retain the heat in the arch. You keep asking us questions and we will have you in a force 5 pretty soon. lol

[Loun]

next year I want to be into a "real" arch. We have a "potting shed" here that would be an awesome sugar house so im trying to convince the powers that be, that its a good idea :)

I will see what I can do about the sand deal, that might not be an option. I was going to line the sides with some metal flashing to make it even more tight but decided against it.

what are the odds the chicken wire wont melt? I wanted to make sure I held the bricks back just in case. I need to figure out what to use for a grate IF I cant get that drainage cover. Any suggestions there? So far I have no door, and im leaning towards just a metal sheet I can toss up on a couple blocks and bricks to hold it open for air to get in. So that part will be my tribute to the ghetto side of the hobby :)

I dont know when I will get a chance to cut and bend out the arch but I cant wait to get it all together and take some pics.

http://farm3.static.flickr.com/2762/4320028609_4aa90afbf5.jpg

The chicken wire isnt tied down yet so it looks a lot looser than it will be.

[swierczt]

I think that chicken wire will be gone after a firing or two. I tried to hold some insulation in my arch with electric fence wire and it didn't last too long.

[Stickey]

Looks nice Loun, familiar too. I did mine very similar last year. For your grate, you mentioned angle iron, why not make something up with that. I like the chicken wire, but suspect at some point it will "deteriorate", who knows how long though. I just used the weight of my pan and gravity to keep my firebricks in place, so I think you'll be alright. The piece of culvert your using looks galvanized, be cautious of fumes. What ever you use for your fire door, just remember it's going to get hot. Handles and welding gloves might come in handy.
Enjoy your first boil.
Stickey

[Loun]

It is galvanized, is that going to be an issue? I hadnt even thought about that. if it is I will try to find another solution. My pan will be sitting on the cinderblock not on the firebrick which is why i was worried about them "Falling in" when the chicken wire goes I will just have to be more careful with the wood i suppose.

someone tell me more about the issue with galvi please. Will it hurt the syrup or do I just want to not breathe it in

[Big_Eddy]

Heating galvanized material gives off Zinc fumes. Very toxic, and not at all good for you. Many welders will tell you stories of Zinc-fume fever - try Google. A couple of good firings and it will all be gone, so if you must use it - do a test boil with water only and let er rip for a couple of hours. I'd suggest some more blocks to build up the "arch" instead.

[Loun]

I had searched for it this morning
http://www.finishing.com/85/35.shtml

some say they get sick and this one that i saw says that there isnt long term effects etc etc lol:

From www.sperkoengineering.com/html/articles/WeldingGalvanized.pdf

-------------
When zinc vapor mixes with the oxygen in the air, it reacts instantly to become zinc oxide. This is the same white powder that you see on some noses at the beach and the slopes. Zinc oxide is non-toxic and non carcinogenic. Extensive research(1) into the effects of zinc oxide fumes has been done, and although breathing those fumes will cause welders to think that they have the flu in a bad way, there are no long-term health effects.
--------------

(1) "Extensive Research" means Walsh, Sandstead, Prasad, Newberne and Fraker, Environmental Health Perspectives, Volume 102, Supplement 2, June 1994, 5-46. Provides summary plus 471 references.

Milk seems to help because the fumes aren't really poisonous to begin with.

Yes, ventilate, absolutely. But, no, there is no long-term health risks.


But as long as I know that a couple firings and it should be fine then I guess its not so bad. I just dont want to taint the sryup. im outside so very well ventilated of course. and it will be very closed off from the pan anyhow.

[JuniperHillSugar]

Just a note of caution. I think it is best that the fire (intense heat) not be able to make it to the sides of the pan. That part of the pan that is above the sap will be superheated and it will scorch your sap as it splashes up onto the sides.

I made 4 gallons last year in a barrel stove and large canner and it was all very scorched and dark. It did however have a very rich taste.

Good Luck

[KenWP]

Heating galvanized material gives off Zinc fumes. Very toxic, and not at all good for you. Many welders will tell you stories of Zinc-fume fever - try Google. A couple of good firings and it will all be gone, so if you must use it - do a test boil with water only and let er rip for a couple of hours. I'd suggest some more blocks to build up the "arch" instead.
I take zinc every day for myself and fed it to pigs for 20 years so I doubt if its toxic. The smell when welding zinc can turn a guy off but haveing welded it for 30 years so far nothing wrong with me unless you count maple syrup making.

[Loun]

Ken,

So I dont have to worry about using it on my arch? im more worried about tainting the flavor of the syrup. Thanks!

[SeanD]

Looks like I'll be block arching it again this year. That's a bummer about the potential hazard with the galvanized window well. It's an awesome idea. The DIY part of this hobby is one of the parts I love most. I've got an old window well like that that could have saved a lot of time and fill for my arch (and get a hunk of trash out from behind the garage).

On the other hand - Aren't base stacks, stack pipes, and roof jacks galvanized? That's not meant to sound snarky. I'm serious.

Loun, I stack my fire brick dry and it doesn't fall in, even with wood bumping it. I used half brick and they still stayed in place. Your full bricks look a lot more stable. The chicken wire will be gone in an hour and you'll be more likely to catch a piece of wood on it and pull everything in.

The other big plus about the dry fit is, you can reconfigure things between boils for better draw, heat, etc.

Good luck and thanks for sharing the window well idea.

Sean

[Loun]

Thanks Sean, I have another idea for the bricks too lol.

As for the window well, my other thought was to use a 55 gallon drum and cut the center our of it and use that since its steel, not galvanized and is already curved it would serve the same purpose.