New Barrel Stove

Alternative energy sources
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The usual. As I have two large solar PV systems here, and my lab assistant just put one in, and others are interested in things like this, here's where that stuff goes. This is mostly for things that work now, not "gee someday a fusor will do this" -- we know that, but it's not someday yet.
The hope is to save anyone embarking on this sort of thing a lot of wasted time and money, as at least I have been off the grid since 1980 and have had a lot of practice (and made mistakes you won't have to).

New Barrel Stove

Postby Doug Coulter » Mon Jun 22, 2015 3:52 pm

What do we do around here in late June when it's too hot to breathe? We get ready for when it's too cold to breathe, that's what. Due to an improvement in the fusor, I'm moving to my old office trailer, and due to some feminine influence, I'm nicing that up. Well, the new gas range took the place of the old stove, so the add-on we're building will require a new stove (the old one wasn't great anyway). I got a barrel stove kit from Amazon and did the basic thing, "burning it in" literally, here.

To the guy on Amazon who complained that the damper hits the flue pipe - you obviously have no clue and haven't done this before. They always do unless the flue pipe is perfectly round, and the damper is in the flupipe, not the mount as it is in this kit. The real defect (if any) is that it's in a place where you WILL get burned if you touch it. I rarely touch mine once adjusted for my basic draft conditions, and use air-intake control, but if you are the diddling type - use a .22 or something to shoot a hole about a foot or so up the pipe and install the damper there - like everyone does. To the guy who thought he saw a leak in the above video - there's this thing called draft, all leaks are "innies" - convection, go look it up. That was oil burning off the barrel and kit, and the top bung gasket giving its you'll see in the following pix.

I can't live without a big fat door on top looking into the very pit of hell. There is no freaking way I'm trying to hand in 28" long sticks through that tiny door horizontally. It doesn't work, you get burned or cut on the door, and you get a lousy fire stack. Gimme a big hole and a good view. This might take all day to do (and has, but a short day and I'm not quite done) but it will save more than that in the first couple months of use - not to mention the burn factor. So, since I couldn't find another nice old Ashley cast iron top (the first one took two decades of cajoling to acquire) - I decided to just make a top door.

Since this involves a bit of good ol boy get 'er dun kinda tricks, I thought I'd document them here - if you really need this info, you might have trouble doing this sort of thing, but it should help you understand why things are the way they are.
Based on drum dimensions, I decided I wanted a 14" square hole, and a 16" square top (some fudge and overlap). here's the top. If I'd had thicker metal I'd have used it - but this cut super easy with the Bosch saw, since I carefully used the edge of my tractor cart as a support so no bouncing monkey-motion while sawing. I've had, I think, about every jigsaw made at one time or another - this one is "the one" - blades too, they just rock - so sharp they are a danger even without power. One use of this and you will swear off all use of the Chinese B&D and other crappy brands forever (if not, have you considered giving your self the additional pain of self-flagellation, I'd guess you like pain).
Top door cut from 1/8" mild steel in about 2 minutes, easy

Accept no substitutes

Ok, so I then laid the stove out for cutting it up. Remembering that it's not a flat surface, it turns out that instead of 7" each side from center along the surface, it's about 7-3/8" (I kinda eyeballed this - it ain't rocket surgery and there's fudge built into the design). So, here's what that looks like. Not a pure H cut, as that would make the sides too long and stick up too far - and I'd have issues with that convection thing most likely. We want this only about 2" above the normal drum top, which results in wings about 4" long each. So we will have some extra metal in the top as scrap. I left some small wings on the front and back to bend up and have as support to weld on the front and back pieces, which I'll probably cut out of the same piece of 1/8" thick scrap - 4" by 14" about - I may or may not round off the bottoms, it won't actually matter to the use of this very much.
Barrel markings for sawing

Note there's an opportunity for a little bit of process engineering here. Anyone who has used a jigsaw on sheet metal knows that it's a real pain to be working unsupported - the blade grabs, things bounce up and down, you break blades. We want to do our cuts in an order that leaves support in place till as late in the game as possible to make this easier. Work smart, not hard.
So, make this cuts first - the ridge makes it hard enough anyway.

I went a little off my lines at the right end, so now is the time to fix it - not later when there's no support.
Ugly now, but who cares, it'll fit perfectly.

This beats having to use an angle grinder to remove lots of stuff...
Now we make the circumferential cuts.

We save the scrap cut for last, - finish doesn't matter, and this way we only have to make one cut with a bunch of dangly metal (and yes, I broke one blade and did the last bit with a dremel and cutoff disk).
Almost there and the glitch is in a don't-care place. Ideal.

Next post will handle the metal bending. Perhaps one after that for the welding, hinge design, and of course final testing and re-burn outdoors, as various things are sure to fume heavily (the high temp paint I'll be adding if nothing else).
Posting as just me, not as the forum owner. Everything I say is "in my opinion" and YMMV -- which should go for everyone without saying.
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Doug Coulter
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Re: New Barrel Stove - continued

Postby Doug Coulter » Mon Jun 22, 2015 4:09 pm

Just for reference, perspective.
Showing the melted bung gasket that someone thought was a leak.

Now on with the metal bending. This isn't something I can put in the shop's brake, so we get a little creative with persuaders here.
That's not a wrench. THIS is a wrench.

If you adjust the jaws just so - slightly loose, you can use an adjustable end wrench to get pretty decent results. You don't go for the entire 90 degrees at a time - just a little, move over, a little, and so on, making around 4 passes over the entire bend, then clean up at the apex with a bit of "mr persuader" otherwise known as a 3 lb hammer.
The sharp-eyed will notice I drilled a hole in the stiffening ridge. It's easy to stretch mild steel, but hard to shrink it - so the hole is a place for the metal to go into when I do that bend. Since I will be welding front and back ends on anyway, I'll just plug whatever hole is left there.
Some metal-convincing tools.

Once you get the knack, you can use another hammer for a dolly (backstop) and swing them both at once for simultaneous hits - works better and faster with less effort. I used a welding clamp here as I didn't have anything with deep enough reach but this was close. The trick here is to bend (add hammer to taste) the ridge first - buckle it into the hole and the rest is easy. Here is one side done, with front and back weld-support flaps also bent.
All bent up. Bent into shape for once.

As I mentioned before - it's hard to shrink metal. It IS possible (ask a good bodywork man) this case I just happened to do it accidentally, and imperfectly on the last side. Note the steel has to go somewhere, and rather than getting thicker (possible, but ask that body guy how hard that is) - it got wavy. No biggie, the door covers it all up fine.
And, it does cover the hole. Now I need a front, back, hinges, handle.

More when I cut the front and back, design the hinges so the door will stay open till I close it (gravity and lost-motion in a slotted hinge hole, along with door overhang) and get it welded up.
Note that the front door on this would need a better handle too if I ever opened one other than to get ashes out. it gets WAY too hot where it is even with that spring handle. Spiral burns hurt just as bad as any other kind.
Posting as just me, not as the forum owner. Everything I say is "in my opinion" and YMMV -- which should go for everyone without saying.
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Doug Coulter
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Joined: Wed Jul 14, 2010 8:05 pm
Location: Floyd county, VA, USA

Re: New Barrel Stove

Postby Doug Coulter » Mon Jun 22, 2015 4:35 pm

Just one more for today, as the sun is going down so I can't weld on solar power - why not keep this "pure"? This is also swords to plowshares - it really was an oil drum in its previous life.
Look upon the pits of hell and repent! Or it will be real close once there's a fire in there.
Posting as just me, not as the forum owner. Everything I say is "in my opinion" and YMMV -- which should go for everyone without saying.
User avatar
Doug Coulter
Posts: 2944
Joined: Wed Jul 14, 2010 8:05 pm
Location: Floyd county, VA, USA

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