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Hey Folks,

I´d like to ask for your advise on a project I want to start soon. My shop is half oudoors so I have a roof over the head but literally no walls. Until now I have always had my forge standing just free and hoped for good wind... But as you can imagine I take quite a lot smoke and dust and I mustn´t damage my body with stuff like that at my age. So I want to install a smoke hood over my forge. The only problem is that I only have a very limited budget of about 180$. So I guess I have to take a DIY-solution. After some research and discussions with some fellow blacksmiths I came to the conclution that this design (I know I ain´t very good at drawing...) would give me the biggest bang for my buck:

This is my shop:

Schmiede_Ponderosa_fuer_Internet_1_von_2

Schmiede_Ponderosa_fuer_Internet_2_von_2

And this is the design I´d like to try:

Rauchfang_Schemenzeichnung_1_1_von_1.jpg

The hood will be built from an old oil barrel, cut out on the front and bent upside to form a guiding-shield. On top of that the chimney will be installed reaching through the roof of my forge with min. 8" diameter.

Would you also advise me to do it like that or do you have a solution (any construction plans) that might be more (cost)effective?

I´d be very happy about any advise you give me!


- Daniel

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It would work to some extent but with low walls you'll still have a problem with wind blowing the smoke away from your flue pipe. I'd suggest you also put up a tarp above your short wall to minimize the effects of the wind.

Also go with at least 10" (250 mm) pipe above your barrel. Eight inches is not large enough for the volume of smoke the forge will produce.

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It would work to some extent but with low walls you'll still have a problem with wind blowing the smoke away from your flue pipe. I'd suggest you also put up a tarp above your short wall to minimize the effects of the wind.

Also go with at least 10" (250 mm) pipe above your barrel. Eight inches is not large enough for the volume of smoke the forge will produce.
Perhaps I will have to do further improvements on the shop and the forge. But I actually don´t need a perfect result. Just a little less dust in my neck and smoke in my lungs would be very nice already ;D.

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On your budget you can buy a 20 ft piece of steel culvert pipe, 12 inch, like used under driveways. Hang that over the fire. Pictures of Brian Brazeal's shop show this exact setup with no hood.

you can see it in the background of his picures
https://lh6.googleus...03/PA090034.JPG

there are a lot more to look at if you want
https://plus.google....bums?banner=pwa

Phil

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You could always lower the pipe down into the forge table and cut out the opening and flap like to plan to do on the oil barrel. You could even use the oil barrel as the hood and still use the culvert for the stack.

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The best flue i have ever worked with is brian brazeal's -
Simply a 12 inch flue pipe - the bottom of the flue pipe is about 20 inches above the fire and draws fantastically and is very affordable the pipe should cost less than 70$ - and then you will be able to invest the savings into steel or coal or further improving shop further!. i would definitely recommend this over the previously suggested design - simplicity is key!

alec

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just looked through all posts - exactly what Phil K was describing is what i am suggesting!

Please explain why you think the wind in your shop will be too strong for that though? i hugely doubt wind would change anything.

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Well I have to see where I can get these flues and how much they cost here... My point with the wind is that the opening is not "THAT" big and the flue stays quite high over the fire and gives me no protection from the sides so the wind might just blow out all smoke. But I have no experience yet with that so I will give it a try. Maybe I will just combine both the barrel and the flue...

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what fuel are you using? proper fire management skills will mean that the only point in time where there may be excess smoke is when lighting. That is the only time you may have some smoke trouble - other than that the wind wont affect it - especially with the location of your forge in your shop!

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what fuel are you using? proper fire management skills will mean that the only point in time where there may be excess smoke is when lighting. That is the only time you may have some smoke trouble - other than that the wind wont affect it - especially with the location of your forge in your shop!
Right now I am using the "Heizprofi Schmiedekohle" by Rheinbraun Brennstoffe. But the quality of them became worse so I have trouble forgewelding so I think of transfering to coke. You might be able to see some of the wind issues also in my YT-videos...

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i am currently looking at your youtube videos, the wind does not look too bad really, that amount of wind even when starting the fire should not affect the draft of the flue very much!
Coke will reduce smoke and make fire management for avoiding smoke alot easier also! it could be a wise change unless you have a very shallow firepot!
I am enjoying you youtube videos very much!
I love the videography skils! very impressive! did you say in one of your videos you were using a canon 600d ? wat lens are you using also? your videos have a very nice effect that go well with the content!

alec

youtube name - alectheblacksmith
( only the most recent video is worth watching though! ;) )

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I made my forced-air side-draft hood with some stuff I had laying around the shop. An old portaband box, a bean can, and a section of 1 inch pipe. I wrapped the 8 inch bean can with 1 inch fiber blanket and it acts as a step with 10 inch pipe slid over it.

The chimney is just barely taller that the garage door opening, much lower than the roof so it's not tall enough for the smoke to dissipate completely from the surrounding area. But it's plenty to keep my shop from filling with smoke. It even draws with out the blower once the air is hot enough and moving.

Hope this inspires some ideas.

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The most effective setups I have observed have been side-draft setups. Essentially, this is no more than a box (with a chiminey attached) with a relatively small opening adjacent to the fire.

I have a smithy outside also and it has worked very well. After I start the coal fire, I ball up a newspaper, light it, and toss it into the chimney opening. This starts the updraft and (subsequently) the draw into the opening.

Eight inches in diameter for a chimney pipe may not be enough to be effective..... 10 or 12 inches would be better. Although you may not be able to find 10-12 inch pipe at a big box store, remember you can snap two smaller pipe sections together to make a larger diameter pipe. I made my chimney using heavy tin and light angle iron (it's put together with self tapping screws).

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post-585-0-82862100-1345667263_thumb.jpg

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You've been given some good advise on hoods, I don't have any better solutions. I do have a suggestion though. Shave the bark off your anvil stumps. Leaving the bark on will invite insects and hold moisture which will lead to rot.

Very nice couple of anvils by the way.

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I'm surprised no one's mentioned the Hofi style chimney.

http://www.iforgeiro..._+hofi +chimney

which, wind or no wind, would move the smoke away from you, offset a couple of feet back thru the wall behind the forge.

As soon as I can scrounge up some non galvanized ducting, I'll be replacing the 10 inch tube and "hood" over my forge.

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I made my forced-air side-draft hood with some stuff I had laying around the shop. An old portaband box, a bean can, and a section of 1 inch pipe. I wrapped the 8 inch bean can with 1 inch fiber blanket and it acts as a step with 10 inch pipe slid over it.

The chimney is just barely taller that the garage door opening, much lower than the roof so it's not tall enough for the smoke to dissipate completely from the surrounding area. But it's plenty to keep my shop from filling with smoke. It even draws with out the blower once the air is hot enough and moving.

Hope this inspires some ideas.
looks pretty good!

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You've been given some good advise on hoods, I don't have any better solutions. I do have a suggestion though. Shave the bark off your anvil stumps. Leaving the bark on will invite insects and hold moisture which will lead to rot.

Very nice couple of anvils by the way.
Good advise. And thanks the red one is my anvil the second one belongs to a friend of mine. Both I brought home from my visit at Joe´s shop. These are by the way Swedish made Kohlswa anvils ~200lbs.

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I'm surprised no one's mentioned the Hofi style chimney.

http://www.iforgeiro..._+hofi +chimney

which, wind or no wind, would move the smoke away from you, offset a couple of feet back thru the wall behind the forge.

As soon as I can scrounge up some non galvanized ducting, I'll be replacing the 10 inch tube and "hood" over my forge.
Also very interesting setup! But I am afraid I´ll have trouble getting the materials needed for it on my budget though.

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Also very interesting setup! But I am afraid I´ll have trouble getting the materials needed for it on my budget though.


The Hofi chimney is simply the same vertical 12 inch pipe with a box duct to bring the draft to the fire, so you do not need to penetrate the roof, but can go outside the roof. The horizontal box is all that is needed extra. It can be made from scrap sheet metal if needed.

Phil

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Go to this site for a COMPLETE discussion of chimneys and how to make them work: http://www.beautifuliron.com/chimneys.htm .
There will be something there that will fit whatever your needs are.

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OK, ... here's what I'd suggest .....

Lay your oil drum on it's side, and make 1 cut, end to end, starting at the edge near the 2" bung.

Now, ... starting at the ends of your first cut, ... cut 1/4 of the way around the ends, ... in each direction.

Viewed from the round end, ... with the 2" bung at the 12 o'clock position, ... you should now have a cut from12 o'clock to 9 o'clock, and from 12 o'clock to 3 o'clock, at both ends, ... and the side cut from top to bottom, at the 12 o'clock point.

Assuming your oil drum has the typical 'stiffening" rings, ... draw a line from where the cut ends, at the 3 o'clock points at one end, to the 9 o'clock points at the opposite end.

This is where you'll bend out the "wings" of your hood, ... but first, you'll need to nick through the stiffening rings, so that the "wings" can bend out on a fairly straight line.

This should yield a hood that's about 3' square.


Now, ... rather than cut your roof, ... cut your "side draft" pipe into what was the bottom of the drum, and turn an elbow up from there, so that it clears the edge of your roof.

Hang the hood at the desired height, from chains attached overhead.

If you want, you can now cut away half of what was the top of the drum, ... thereby eliminating the 2" bung portion, and making a fairly straight bottom edge..

If air flow across the forge is still an issue, it's a simple job to hang flat sheet metal from the back edge, or from the discharge end of the hood.

That should come in well under budget. :)

Good luck.

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On your budget you can buy a 20 ft piece of steel culvert pipe, 12 inch, like used under driveways. Hang that over the fire. Pictures of Brian Brazeal's shop show this exact setup with no hood.

you can see it in the background of his picures
https://lh6.googleus...03/PA090034.JPG

there are a lot more to look at if you want
https://plus.google....bums?banner=pwa

Phil


Been forging now under a short roof out the back doors of my shop. No vent. Very smoky. I like the 20' steel culvert idea. Does anybod have any guidance on how to mount this. It would need to go through a roughly 8' high sloped roof and then be mounted securely. I live in Southern Louisiana so it needs ot be able to withstand some inland hurricane winds. Here is a pic that might be helpful.

Any and all advice on how to get rid of the smoke with my set-up is welcome. I might even consider building a brick forge and stack. But I would like to get this done sooner than later. Also, how do you manhandle such a large item. I have a compact tractor that might be useful to somehow strap it too to ease it in place.

post-16782-0-16645100-1345824080_thumb.j

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http://www.metalculv...gweightscms.htm
this says 12 inch is about 10# per ft, so a 20 ft piece is 200#, depending on the exact product.

You may not need a full 20 ft however. Stoves recommend a minimum rise of about 13 ft of chimney, and an above the roof clearance.

I suspect they are held in by bands and hangers, supported at the roof, and by some hangers leading up to adjacent joists. It is entirely possible Brian Brazeal made the hardware.

Phil

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