New build questions

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Re: New build questions

Postby matt walker » Fri Dec 13, 2013 10:00 pm

I think the more the better, but only to a point. I'd say 12" would be adequate, a bit more even better. I think the book calls for a 1.5" gap from insulation canister to outer drum, but I personally prefer a larger gap there. Also, the larger the gap there, the easier time you will have making a large transition to the horizontal flue. So, yeah, 12"-14" is what I would recommend.
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Re: New build questions

Postby mannytheseacow » Sat Dec 14, 2013 12:27 am

I'm pretty excited to see what you come up with, abarlow. I've been brainstorming for a second heater in my upstairs that could double as a cook surface in the winter; between your build, hagrid's build, and the Haiti cook stove that Guy posted, I'm getting closer to figuring out what I want to do.

I think you've got two things going for you- you've got a small space, and Seattle is a mild climate. I think a 6" will do just fine for you. What are you thinking for a mass? A bench or a counter? Warm counter might be kind of weird, but then again a warm bar- hmmmm that might be close to the greatest invention ever.

Seriously though, height will be a consideration if you are going for a cook surface. Personally, I think recessing it into the floor is what I would do, if that is an option. I don't think that clean outs would be that bad. The top of my barrel is 52" off the floor. I could have maybe squeaked it down to 48" but that's pushing it. You could try a smaller barrel? But then you're limiting your insulating width of your riser. I dunno, Matt's the whiz with the dimensions so definitely follow his lead on that.

I used standard 6" flue for my riser and a 12" fireplace collar for the outer form. Those concrete tubes would work well for both and that would be the cheapest route if you don't have time to scrounge stuff up.
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Re: New build questions

Postby matt walker » Sat Dec 14, 2013 2:31 am

Well, I just got back from Home Depot with some stuff for a new build. I might have something to show along these lines by the end of the weekend, if I don't get too distracted. I've been wanting to tackle a counter height heater for a while now. I don't want to suggest my concept to you yet Adam because it's a pretty significant departure and I want to make sure it works before I send anyone else on a wild goose chase.
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Re: New build questions

Postby abarlow » Sat Dec 14, 2013 11:00 pm

Thanks for all the replies. Going below floor will likely be complicated for me. I think i won't do that until i can't make another thing work. So at this point i am gearing up to do the normal thing. I might be delayed as our car just went kaput, but hopefully only by a week or so.

Still hoping to buy some supplies today.

Concrete tubes? For which part? Wouldn't they be too thick?
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Re: New build questions

Postby mannytheseacow » Sat Dec 14, 2013 11:19 pm

Oooh, sorry to hear about your car, Adam... that sucks!

I think the below floor thing would be awesome, but I'm speaking only as a voyeur... I could have done it at my place too but if it doesn't make sense, then it doesn't make sense. By concrete tubes I meant those cardboard tubes that they use to pour concrete footings. It's just a cardboard tube and you can get them in about any size.

Good luck!
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Re: New build questions

Postby matt walker » Sat Dec 14, 2013 11:28 pm

Ugh, car problems. Sorry man. I just finished casting a core and have a drawing for a system I'm pretty excited about. I should be able to do a test burn tomorrow and if it doesn't totally fall on it's face I'll post it up tomorrow night. Might be a solution for the height thing, maybe.
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Re: New build questions

Postby pa_friendly_guy » Sun Dec 15, 2013 12:20 am

Would it be possible to extend the sideways burn longer before the fire is sucked up the burn tube into the barrel? Would that still give you a complete burn and have the advantage of lowering the cook top? I am asking questions here, but it seems to me that the effect would still be the same. Maybe harder to get lit and to get it to draw at 1st, but once it is running I don't see why it would not draw.
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Re: New build questions

Postby hpmer » Sun Dec 15, 2013 12:41 pm

The whole 'in the floor thing' seems quite attractive on the surface. I just built one outside using Matt's bbq idea. Mine is a 4" with the top of the feed tube at ground level. That puts the bbq at a pretty good height ergonomically.

That said, it's more if a pain to light and clean out. It also doesn't work very well for other reasons (4" is too small, I think the ground is acting as a huge heat sink, etc.).

I think a better alternative, at least for me, is to build a little step up to make the ergonomics better and leave the rest of the system well enough alone. I'm going to have to rip the thing out in the spring and start over.

So, I'm with Matt. It's easier to maintain if you don't have to get down on your hands and knees.
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Re: New build questions

Postby matt walker » Sun Dec 15, 2013 5:23 pm

Guy, that's an idea I've played with a bit. The biggest flaw there is that to maintain draft through that longer initial horizontal section, you unfortunately need MORE riser. As you shorten the riser, you need to shorten the tunnel and feed as well, or the whole thing starts to get really finicky. There's the rub with trying to make a low height system of any significant size.

Hpmer, I came to the same conclusion for outdoor cooking. Rather than trying to lower the cooking surface, my solution ultimately is change the surroundings to have different grades. I picture a very nice outdoor space with different elevations of patios surrounding an outdoor system. That one will have to wait until I win the lottery.
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Re: New build questions

Postby pa_friendly_guy » Mon Dec 16, 2013 12:36 am

Well, that answers that question Matt. :D I thought there may be some problems with that idea, mainly the draw, but I did think it would work once it got hot. Thanks for letting us know from hands on experience that it won't work well. ;) There is no substitute for experience, None. :lol:
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