Jump to content
I Forge Iron
JHCC

Helium Tank Super Sucker

Recommended Posts

Background: as some of you know already, my forge is in my garage and has no provisions for removing the smoke. I've been using primarily anthracite, which is relatively smokeless, so that hasn't really been a problem. Of late, however, I've been using a couple of different kinds of bituminous, and the smoke has required me to wear a respirator while forging. Works, but inconvenient.

A week or so ago, I salvaged about a dozen feet of 10" flue pipe with some flexible elbows. Realizing that I could run this horizontally out the door of the garage, I set to work making a scaled-down version of the Super Sucker hood discussed elsewhere on IFI and other blacksmithing fora. However, I realized that I could save myself some hassle by simply using a helium tank (acquired for a now-shelved gas forge project) that already had a 10" hole cut in one end. 

(Side note: for the horizontal flue to reach outside the garage, I had to rotate my entire setup 180° to get the forge next to the door. That meant draining the bosh, shoveling out the sand and ash fill, moving everything (including the anvil and treadle hammer), and figuring out any changes to my layout while I had the chance. Why do simple projects always get so complicated?)

The original Super Sucker was designed for use with a 12" dia. flue, with a 10" square opening. On the scaled-down version, that opening is about 8" square, which is roughly the same proportion. The key design concept -- a smaller opening connected to a larger volume that creates a stronger draft -- remains the same.

Here's the tank sitting in the forge. You can see where the top had already been cut off and one of the marks for cutting the front opening.

D5526C6D-B3D7-4902-8A3B-53B7B6290E95.jpeg

Here's a test burn with some brown paper. Decent draft.

35799A10-B388-46EB-9CA8-D39C1C4DA743.jpeg

This is the new hood set up with the horizontal flue. Note the nice clean sand, which won't stay that way for long.

4810333B-1316-4B1F-8C96-E00B2AE290CA.jpeg

Here's the horizontal flue seen from outside the garage. It ain't elegant, but it appears to work.

FF6E2D67-95FD-4E0E-B8DD-2E086FADED2A.jpeg

I took a video of another test burn once it was in place, but I couldn't get it to upload to YouTube. I'll try again later.Initial observations: decent draft. I suspect it will be better with a full-size fire pulling hot gasses up the flue. Also, the fit of the flue in the hood is pretty sloppy, and I think it's leaking smoke out and draft in. I have an idea for fixing that, though, and will be trying it soon. More to come!

 

Share this post


Link to post
Share on other sites

Suggest you round the corners of the opening to the tank. This creates less opening area and increases the suction a bit. Once clear of the garage door, a more vertical chimney will also increase the draft.

Share this post


Link to post
Share on other sites

Good thoughts -- thank you. I still have the cutout from the opening and can easily make a couple of arched corners from that and tack-weld them in place. As for the vertical pipe, we'll see what the salvage gods send my way.

I think if I make the sawhorse support somewhat taller, that will increase the upward slope of the flue and improve the draft a bit as well.

Share this post


Link to post
Share on other sites

JHCC. my original flue was smoking up my shed horribly, so I ran a slanted 12" flue out the end.  Works like a charm.  Your outside double elbow might be restricting the flow a little (maybe none at all) so you might try a straight slanted flue without the double elbow.  If it's a problem with the upright supports, maybe you can modify them.

 

New flue pipe Nov 2017 01.JPG

Share this post


Link to post
Share on other sites

The double angle in the middle is jammed, so that’s about the best I can manage. I’ll try tweaking the bends at the ends, though. 

Here’s a piece for the arch, awaiting welds. 

A47702C8-E2D8-4F72-8EF2-7545641AE702.jpeg

Share this post


Link to post
Share on other sites

Sometimes trying to adjust those elbows will drive one to the nuthouse!

Share this post


Link to post
Share on other sites

Update: welded in the arch (messily, because my welder setup is a bit overpowered for this thin steel, even at its lowest setting), switched out the flue supports for something taller, and made a gasket to tighten up the connection between the hood and the flue. Performance is definitely improved.

The gasket is made from the bottom of another helium tank (currently doing duty as my slack tub) with the center cut out:

D49164A1-21E9-4857-94EE-7FD3C500DC15.jpeg

The edges are notched, with three of the tabs bent down to keep the ring in place:

4F78475B-10C6-42DE-8BB3-79ADA60AE3B6.jpeg

The flue, gasket, and hood are not attached together, so each can be jiggled around to get the best possible fit. Gravity holds the whole thing together very tightly:

D0C9704A-5292-457F-BC62-86F906C18252.jpeg

And here are the new flue supports:

E80F18E7-7AF2-464E-8B6E-382C449CB6D3.jpeg

(The astute reader will observe that with the old motto largely obscured by the new hood, it has now been rechalked on the other side of the bosh.)

Share this post


Link to post
Share on other sites

Okay, here's the video of the initial setup.

I'm still trying to get the video I took of the hood after modifications to load.

Share this post


Link to post
Share on other sites

And here's the performance after modification.

 

Share this post


Link to post
Share on other sites

When you have a chance, add a say 3 inch piece of sheet metal to the arch like a porch roof. Then add wings to each side. The wings will help keep the room air from getting into the helium tank, allowing only the smoke from the fire to enter. The wings do not have to go all the way down to the forge if the wings interfere with heating your metal. In fact the wings can be just pieces of sheet metal that lean up against the helium tank. All this increases the draft up the chimney and should keep most of the smoke out of the shop.

Bending the chimney to vertical (or near vertical) as soon as it is outside the shop will increase the draft. You may want to make a connection point at the door of the shop so the chimney would be in two sections for easier handling, and storage.  

Share this post


Link to post
Share on other sites
2 hours ago, Glenn said:

When you have a chance, add a say 3 inch piece of sheet metal to the arch like a porch roof. 

Like this?

4E77E156-E10D-4861-9B81-C0F56A26FFA2.jpeg

Share this post


Link to post
Share on other sites

I have to wonder though if it will suck too much and that some of the flame will go up the chimney.  My wood stove, if not dampered, would such the flames right up the stove pipe and into the chimney.  It seems with a normal side draft hood that it's not enough draw to actually draw a large flame out of the coal, but if it's a super sucker maybe it will draw out a lot longer flame.  Being a propane guy, perhaps I'm just asking a dumb question.  

Share this post


Link to post
Share on other sites

The last time I fired it up, it sucked the hammer right out of my hand, up the chimney, and into the neighbor’s yard. I was standing there with my mouth open, and it sucked the fillings out of my teeth. 

Share this post


Link to post
Share on other sites

Guys, put your hip waders on... it's getting deep in here!!!!!!!!:o

Share this post


Link to post
Share on other sites
3 hours ago, JHCC said:

it sucked the hammer right out of my hand

JHCC: what size hammer?

The draft from the 55 Forge with the supercharger will suck the fleas off a dogs back.

Share this post


Link to post
Share on other sites

Now that's funny JHCC.  Thanks guys for letting me down easy with my dumb question :D

Share this post


Link to post
Share on other sites

MC Hammer: Not to worry. There's a critical difference between a forge chimney and a woodstove (or fireplace) chimney. With the latter, there's a balancing act between enough draft (to keep the fire going and the smoke moving out) and too much (where you overheat your chimney and burn up all your fuel). The goal, after all, is to heat the room.

With the former, on the other hand, the goal is to heat your workpiece, and you really don't care what happens with the heated air and the smoke, so long as it clears out of the shop. In that context, as long as your flue is durable enough to withstand the heat of any flame, you don't mind hot gasses going up, because that's never going to be heating your workpiece.

Glenn: the one on the left. 

F5D865EB-AFE1-4054-8001-DDAA06E8605D.jpeg

Share this post


Link to post
Share on other sites

JHCC :  Yes, that makes sense and is in line with what I've seen and read about coal forges.  Being a gas for guy, it will be a whole new experience when I inherit a farrier friend's coal forge that passed away recently.  I really did want a coal forge and a gas forge so this will be a good thing.  Now when I finish off the new shop I can plan on both forges as far as stacks go.

Share this post


Link to post
Share on other sites

Okay, first actual forging fire with the new hood:

 

I am VERY happy with this. There was practically no smoke anywhere other than headed up the flue (or burning off the outside of the helium tank, but that didn't last).

The only change I think that I will make will be adding about an inch of sand underneath the bottom of the tank. I think the hood is sitting just a hair low on top of the fire, and this should help. Other than that, everything is great.

Share this post


Link to post
Share on other sites

That worked very well...  congrats on becoming smoke free..  Or is it smoke less.. :) 

I don't really care what kind of fuel it is. .   having a lack of smoke with it all going up the stack is a good thing.. 

I love the last video..  Something that always gets me in the " Coolness zone"..   

Share this post


Link to post
Share on other sites

Thanks, Jennifer. Pretty much the only smoke that wasn’t going up the stack was the smoke coming off the outside of the stack!

After the fire really got going, a lot of the paint burned off the outside:

CA2A4F58-804B-45E7-ADC6-C17FF45C9C93.jpeg

Share this post


Link to post
Share on other sites

Yup, nicely done..    I really love the inventiveness..     One of my first forges was an oil pan from a Semi tractor..   On another forge i used an old fashioned wash tub.. :) 

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...