Home made stack.

[Woodsymiles]

Been researching stacks, looking to put one together for a 3x10, found some 24 gauge 12" metal duct pipe, any one use this for making a smoke stack, most 12" is 26 gauge but was able to find some 24g, I have 24g on my wood stove so thinking this duct pipe should work.

[CampHamp]

Galvanized steel duct? It worked for me before I got a SS setup -- it did start to rust fairly quickly. Careful you don't breathe in the zinc as it burns off (someone here mentioned it as a very serious concern).

[Woodsymiles]

Yes, galvanized metal duct. Sugar house is pretty vented but would be a good idea to leave door open and a fan on until she cooks for a bit, I have taken our last stack down after the season was over, this should help it last, high heat spray paint may help some too. Making the base, now that will be fun!

[maple flats]

Unless you have AOF I doubt you will find a hi temp paint that will hold up to the temps you will get in an arch stack. 26 Ga is going real light for a stack. I don't think I'd trust it to work even for 1 season. If you must make your own go at least 24 ga. but 22 and 20 ga is std for evaporator stacks is galv.

[Michael Greer]

The burning zinc is a pretty serious concern. it will make you deathly ill if it doesn't kill you. If you can't yet afford stainless, then use black stove pipe and throw it away after a few years. Don't poison yourself.

[lpakiz]

Michael is right. Burning galvanizing can make you very ill. I was affected years ago, as a young fella that didn't know that. I cut a 48 inch galvanized culvert in half. Headache, nausea, stiff sore joints, etc. Be careful there.

[Woodsymiles]

Ok, what's up with the pipe from maple suppliers being galvanized too, is it less of a coating or something, it will burn off after a firing?

[Woodsymiles]

Also where could I find 12" diameter black stove pipe?

[MaxJ]

It's just bad burning anything that zinc coated, it was of the one coatings that welders and to archers always used cartridge masks for the fumes.
3-Respiratory System :

Most zinc salts irritate mucous membranes of the upper respiratory tract after inhalation.

a-Zinc chloride :
Inhalation of zinc chloride may cause :
-cough,
-dyspnea,
-adult respiratory distress syndrome, death, resulting from delayed pulmonary vascular fibrosis.

Ten deaths and 25 cases of non-fatal injury occurred among 70 persons exposed to high chloride concentrations of zinc chloride released from smoke generators. Of the 10 fatalities, a few died immediately or within a few hours with pulmonary edema, whereas those who survived longer developed bronchopneumonia. On dissolution of zinc chloride, both hydrocloric acid and zinc oxychloride are formed, contributing to the corrosive action.

[Woodsymiles]

If evaporator stacks are not stainless they are galvanized, they are advertised as galvanized on the web sites. Thinking of burning the duct stacks in a bon fire first to burn coating off, that should work, I'd hope.

[Woodsymiles]

Yup, going to scrap the galvanized duct pipe and go another route.....any good deals out there on custom 12" black stove pipe?

[SanfordSyrup]

I read a few articles that said that galvanization is only harmful to you if welded on (or heated above 2360C). This is because welding can have a higher heat input than a wood fire. The zinc will form an oxide layer at lower temperatures (as seen by a grayish/white discoloration of the galvanized steel surface) seen in wood fired applications. This zinc oxide layer will not release any zinc oxide fumes (which would cause "weld fever") until the metal reaches 2360 degrees C. If that is in fact true and you are not getting your galvanized pipe up to those temps then you should be fine.

[lpakiz]

Sanford
I did not know that. Very helpful to lots of folks, I'm sure. THANKS!

[michael marrs]

okay , I got some questions.( newbie, 2nd year) My block arch is 4ft. x 20 in. I will be using steam table pans. Last year, I did not have a stack, and am curios with my arch a bit drafty, why I need one? Also if I go to one, can I use galv. as I do not have a shack , and am outdoors? Last year, when I made my syrup, I sent some to my daughter, who said it was the best she had ever had, because of the slight smokey flavor, ( which I could not tell.. We just cooked it over an open fire, not a tight arch, or confined area. so this year, with my pans , I will have a small gap for any smoke to escape. I can get black 6in. chimney pipe from my hardware if needed.

[LoghomeShooter]

On my block arch I used hollow 8" cinder blocks that I stacked to use as a chimney, it seems to work okay, a 6" metal might work better.