Jump to content

Recommended Posts

Hey all,

I have gotten a lot of questions locally about my self built forge burner, so I figured I would post some pictures here as well.

I designed this burner based on a hybrid of a blower burner and a Venturi burner.

My original intent was to use it as a Venturi burner until I could put together a blower assembly for it, but it works so well I have never bothered to do the blower.

 

Standard disclaimer: I can not be responsible for your actions! Please build responsibly! Propane is flammable and in just the wrong mix it is explosive! DO NOT attempt to build a propane burner without first understanding the function of each part and how they work together. This information is just that, information, please do your own homework before attempting to use any information from any source.

*Don't forget to check on any local building codes related to propane appliances or tank location etc.

*DO NOT USE GALVANIZED PIPE, use only brass and black iron piping as specified, parts of the burner will get hot and galvanized pipe releases NASTY fumes when heated.

* This burner design easily reaches temps in excess of 2,000 degrees F, producing damaging IR spectrum light! I strongly recommend the use of IR shade 3 glasses whenever looking into a hot forge (my personal thanks to Dave Stephens for this piece of advice!)

 

 

OK on to the burner, I have no way to measure the BTUs, but according to the BTU calculator on Ron Reil's burner page (ronreil.abana.org/design2.shtml) when tuned to a neutral burn, it should produce 46,000 BTU per hour at 5 psi and 93,000 BTU per hour at 20 psi. Those figures are consistent with my gas consumption rates, so I am fairly confident in calling them accurate. I will say it is easily capable of welding heat and turning 1/4 in mild steel rod stock into a sparkler...not that I have ever done such a thing: :wacko:

Parts list

1/4 in ID gas rated ball valve

2 in long 1/4 inch ID threaded brass pipe

4 in long 1/8 inch ID threaded brass pipe

1/8 in brass Female threaded coupling

1/8 in male brass plug

You could replace the coupling and plug with a 1/8 in threaded brass cap, I wasn't able to find a cap.

Brass contact nipple for a MIG welder (0.035 in; 0.9 mm)

1 1/4 in Black iron pipe T junction

1 1/4 in x 1 in Black iron reducer bushing

1 1/4 in x 3/4 in Black iron reducer bushing

3/4 in x 1/4 in Black iron reducer bushing

You can replace the last 2 bushings with 1 1/4 in x 1/4 in Black iron reducer bushing if you can find one.

18 in long x 1 in Black iron pipe

3 in square sheet steel

3/4 in #6 machine screw

largish ball point pen spring (needs to fit over the machine screw shaft)

Pipe thread sealant RATED FOR Propane!!!

High Heat spray paint (I used Rustoleum brand, rated for 1,200 degrees F)

 

Tools:

pipe wrench

tap wrench

#6 NC 32 tap and appropriate drill bit

1/4 in NF 28 tap and appropriate drill bit

1/8 NFP tap

crescent wrench or 2

 

First off, assemble the Black iron pipe as shown using a small amount of thread sealant:

0629131736a.jpg

1 in pipe off one side, 1/4 reducer bushing on the opposite side with the perpendicular opening left open.

Once assembled, clean off any excess thread sealant so the paint will stick, then paint the entire assembly with the High Temp paint.

 

Set that aside and start on the Brass fittings use plenty of thread sealant, I don't bother to paint the brass.

On the inflow side of the ball valve, attach whatever propane fitting is needed to connect to your propane source. For mine this was a 3/8 in flare fitting.

Take the 2 in long x 1/4 in brass pipe and tap one end with the 1/8 NFP tap, then thread the opposite side into the outflow end of the ball valve.

0629131737b.jpg

0629131737.jpg

Take the 1/8 in brass male plug and drill a 3/16 in hole through the center of the face and tap it with the 1/4 in NF 28 tap. Then thread the MIG nipple into it, the plug into the coupler and the coupler to the 4 in long x 1/8 in brass pipe:

0629131737a.jpg

 

Next slide the 1/8 in brass pipe and MIG nipple assembly down the 1 in black iron pipe such that the end of the 1/8 in brass pipe protrudes from the 1/4 in reducer bushing and the MIG nipple points down the pipe.

0629131738.jpg

Thread the 1/8 in brass pipe into the end of the 1/4 in brass pipe that was tapped earlier:

0629131740.jpg

Then slide the brass assembly into the black iron pipe threading the 1/4 brass pipe into the 1/4 in reducer bushing:

0629131743.jpg

The 1/8 in brass pipe and MIG nipple assembly should point down the center bore of the 1 in pipe extending through the T and into the 1 in black iron pipe.

0629131744.jpg

The careful observer of that last picture will note a small hole in the rim of the open end of the Black iron T. That is drilled and tapped with a #6 NC 32 tap. Drill a 5/32 hole in the corner of a small piece of sheet steel, place the spring over the shaft of the #6 machine screw then put the screw through the corner of sheet steel and thread into the drilled and tapped hole on the rim of the Black iron pipe. This provides a damper for air control. Note, the spring needs to be stiff enough to keep the sheet steel in whatever position you slide it (open; closed; partial...)

20130707_205712.jpg

Here is a pic of me and my assembled burner during it's first test burn 4 years ago (NOTE: This burner will not sustain a flame outside the forge unless the damper is closed, robust air flow will literally blow the flame out. I have my hand covering the opening on the T since I had not yet fitted the damper.)

Burner Test.jpg

 

I will cover the flare nozzle in a reply post since it is integrated into the forge design.

Hope this helps someone, any questions shout em out.

 

James

Edit to add orfice size on MIG contact nipple and to correct thread count on the 1/4 NF 28 tap.

Finally added pic of damper assembled.

Edited by James Spurgeon

Share this post


Link to post
Share on other sites

Sweet! thanks for sharing!

Share this post


Link to post
Share on other sites

Timely for me as I just got a large scrap propane tank today and I'm planning on making a vertical forge out of it. Just starting to look at my burner options. If this will work for a blower powered unit I would need to know how to attach it. This looks very good and something I can do.

 

Thank you for sharing.

 

20130703_141100.jpg

Share this post


Link to post
Share on other sites

Timely for me as I just got a large scrap propane tank today and I'm planning on making a vertical forge out of it. Just starting to look at my burner options. If this will work for a blower powered unit I would need to know how to attach it. This looks very good and something I can do.

 

Thank you for sharing.

 

 

No problem, to use this with a blower, omit the sheet steel damper and plumb your air source to the T fitting.

 

One thing to point out with this burner compared to the burners in the blown burner sticky:

This burner has a focused nozzle for the gas relative to the 1/4 inch nozzle on the other. So this burner needs higher pressures in the gas line to supply the same gas volume.

 

The increased pressure is essential for operation as a venturi as the velocity of gas injection determines the strength of the draft it creates through the air inlet.

 

As a blown burner the velocity is not critical, but pressure still needs to be higher to maintain the volume of gas.

 

James

Share this post


Link to post
Share on other sites

Thanks for posting this info

Share this post


Link to post
Share on other sites

James,

 

I will keep that in mind.

 

Thank you,

 

George

Share this post


Link to post
Share on other sites

Just to let you know, that is a great variation of the Modified side arm burner that I have seen from another site (actually bought mine from the site, as I don't have the tools to build one just yet). I belive the capable BTU output you are seeing is right around 15,000 btu's, which is well enough power to bring a 350 cu. in. forge to welding temperatures.

Share this post


Link to post
Share on other sites

I got PINNED!?!

I feel honored, or is that humored, can't tell some days. :mellow:

 

Headed out to the barn now to get a pic of the damper.

 

 

I didn't paint the forge and burner the first time around and I do a lot of welding in it. So between flux damage and rust on extremeties, it was time for a rebuild. <_<

I will add forge build and in use pics as soon as I finish putting it back together.

 

Thanks for all the positive feedback! :D

 

James

Share this post


Link to post
Share on other sites

OK nozzle for the burner:

My forge is heavily used for pattern welding, so it is basically built of fire brick set in a steel frame.

Hard Brick Forge.jpg

The frame holds the burner in position at a hole drilled through the top center brick.

Note the respirator and full faceshield. I strongly reccomend using both when drilling or cutting refractory brick.

20130707_205549.jpg

That hole is first drilled to fit the 1 in burner tube then I use a small hand chisel, masonry hammer and a couple masonry drill bits to taper the inside hole out to roughly 1.5 in.

20130707_205636.jpg

Once the general shape has been cut, I use a tapered 1 3/8 in spade bit to smooth it out.

After inserting the burner into the assembled forge, I seal around the burner tube with a mixture of fine sifted clay and fireplace ash.

 

So, now that my forge is back up and running, here are some pics of the burner in action.

In all of these pics the burner is running at just 4 psi.

Burner flame coming through the flare nozzle right after I lit the forge, while we can still see it.

Flare in action.jpg

Then I put in a large old farriers rasp I plan to turn into a few knives.

Insert steel.jpg

5 minutes later:

Heating up.jpg

Another pic so we can see the swirly in the forge. Not bad for a square forge:

Swirly.jpg

Shortly after that I noticed some steam rising from some of the bricks and had to shut it all down post haste. Guessing the bricks were stored outside at the building supply store. I will let the residual heat finish drying it all out:

Shut down.jpg

4 psi works for general forging but I tend to run it a little hotter, as high as 10 psi, just because I am impatient. Anything above 10 psi will get into welding ranges.

If I go out specifically to do some forge welding I will kick it up to 20 psi, but if I forget to turn it back down to about 15 psi once it heats up I start making sparklers instead...

 

Edit: Almost forgot to say: Don't forget to close the damper when shutting down the forge. Otherwise the chimney effect off the forge will turn all the brass into a limp noodle, if not melt it outright!

 

As always, comments and questions are welcome :ph34r:

But for now, Good night!

James

Edited by James Spurgeon

Share this post


Link to post
Share on other sites

I can't really tell from the photos, but how is this different from the Zoeller design that Chili forge used?

Share this post


Link to post
Share on other sites

I can't really tell from the photos, but how is this different from the Zoeller design that Chili forge used?

 

About $150 different, plus shipping. :ph34r:

It is also possible to remove the damper from this design and plumb in a blower to convert to a blown burner, which can't be done with either the Diablo from Chile Forge or the T-Rex from Hybridburners. B)

 

The benefit to buying one of those is quality control. If you can keep everything fairly concentric and tight, this burner is just as good as either of theirs, IMESHO. :D

 

OTOH if the threads are misaligned or over cut so things end up slightly loose or off center, it will work, but not as efficiently as the production versions. :unsure:

 

On the plus side, if that does happen and the burner is not as efficient as you would like as a venturi, adding a blower will correct it. ;)

 

 

Aside from the $ savings, I also derive a lot of satisfaction from the fact that I am using a burner/forge that I built myself.

 

James

Edited by James Spurgeon

Share this post


Link to post
Share on other sites

http://zoellerforge.com/sidearm.html

 

Zoeller posted this design many years ago. It's been linked and talked about on most of the blacksmith forums. Chili used this design on their forges until they switch to a version of the design Michael Porter has in his book. So my question still stands.

Edited by Gerald Boggs

Share this post


Link to post
Share on other sites

http://zoellerforge.com/sidearm.html

 

Zoeller posted this design many years ago. It's been linked and talked about on most of the blacksmith forums. Chili used this design on their forges until they switch to a version of the design Michael Porter has in his book. So my question still stands.

Well, that is interesting, I had not seen their page before. There are a few minor differences in actual assembly, tube diameter etc., but in practicality they have the same design. <_<

 

If you re-read some of my posts you will note that these pictures are from my recent re-build of my forge and burner...

I designed mine "many years ago" based on a hybrid of a plumbing parts blown burner and Ron Reil's burner page, both of which predate the Zoeller design. I came to the conclusion that I could add the MIG nipple from the T-Rex to the injector on the blown burner and merge it with the Reil burner design and end up with a hybrid Venturi/blower version that would be easier to tune than the Reil burner with its cross axis gas line injector.

My forge design was completely original from the perspective that I had not seen another like it prior to building mine. I originally wanted to do an insulated tube style forge but chose to use fire brick solely because I couldn't afford Inswool and the bricks were available at the local building supply in Staunton. The metal frame on it was required to hold the burner in place and stop me from accidentally knocking the bricks over like I did with my Goddard style temporary forge.

 

Ellis Custom Knifeworks and several other sites also developed nearly identical designs. "Nothing new under the sun" as they say. :huh:

We are all after the same result, so it is little wonder that many of us arrived at similar designs.

 

Feel free to use or endorse whatever design you like.

 

James

 

BTW, I gave up on "most of the blacksmith forums" for any info on bladesmithing many, many years ago as I continually found them to be just as full of mis-information as they were of actual fact. :wacko:

When I first found this site, I automatically lumped it in with the rest and avoided it as well. :o

That is until I stumbled on a post by JPH and realized this was the same guy that covered a significant portion of my reference shelf... :blink:

Live and learn... :P

Share this post


Link to post
Share on other sites

Well, that is interesting, I had not seen their page before. There are a few minor differences in actual assembly, tube diameter etc., but in practicality they have the same design. <_<

I find that to be fantastic.

Share this post


Link to post
Share on other sites

I want to pop in and say thanks to everyone in this thread. I just made my first burner and it works wonderfully! Can't wait to start forging!

Share this post


Link to post
Share on other sites

I want to pop in and say thanks to everyone in this thread. I just made my first burner and it works wonderfully! Can't wait to start forging!

 

Congratulations on the new burner! I'm glad to be of service.

 

I would recommend you get a pair of IR shade 3 glasses to go with it. I didn't think to include that in the original safety comments, but these things get hot enough to seriously hurt your eyes. Regular smoked tint safety glasses block UV but not IR.

 

Flame on,

James

  • Like 1

Share this post


Link to post
Share on other sites

James,

 

First of all, thanks. This got me off my butt to make my vertical forge with Venturi burner. Also thanks to Geoff Keyes for his dimensions in this thread http://www.bladesmithsforum.com/index.php?showtopic=27124 as that confirmed all my thoughts for dimensions. A real confidence booster to do this and get it right. Thanks to you both.

 

That said, I do have a bit of a problem that worries me. My forge gets up over 2000F in just a few minutes and runs quite well, but the burner holder gets pretty hot. I tack welded a 1" coupler to thread my pipe into while I played with it, and I am glad I did. That coupler does not go more than .25" into the forge (i.e. not past the pipe wall, let alone the refractory) yet after 15 minutes running it starts to glow. This has me worried about running for extended periods. How hot does your pipe get and do you do anything special not listed in this post? How deep into the brick does your pipe go? Does the brick end up acting as a flame holder (keeping the flame away from the metal)? I am pretty sure my flame is pretty much starting at the end of the metal so I am thinking maybe I should add a bit of refractory clay to act a a nozzle/flame holder. Good idea? Bad idea?

 

For what its worth, I used 1.5" fiber blanket (Kaowool type, not sure on brand) lining and squished it vertically so it fluffed up to about 1.75-2" thick, then coated it with a very thin layer of hard curing ceramic. The forge body gets warm, maybe 150 or so after 30 minutes of running. I will check more on it later, but I am not really concerned with that, just my pipes over-heating. This forge is hands down way better than my horizontal forge for even heating and speed to heat up. I may have to put together a brick set-up like yours to replace my horizontal set-up.

 

Thanks!

Share this post


Link to post
Share on other sites

Back it down. I do my basic forging around 1600. My burner never gets more than warm to the touch near the forge and is cool at the other end. When I turn it up (5 psi) it runs at 1960 and gets just a little warmer. I do take about 5 mins to get to 1600 and about 3 more to a steady 1960. You don't want to burn the carbon out of the steel.

Share this post


Link to post
Share on other sites

I would like to do some welding with it, so I need hot. Never was able to get welding to work out with the horizontal forge so I'm hoping that this design will work better for heating. I figure small sections is probably a good thing for learning so I'm not worried about the small work area. Even at lower temps I get the feeling that it is going to be getting a little warmer than I would feel comfortable with when running for "long times" (over an hour).

Share this post


Link to post
Share on other sites

Jerrod,

Glad it is working, but yeah if the tip is getting to a red heat I would want to double check things as well.

The tip of my burner sits just inside the hole through the fire brick, just enough in contact with the brick to help keep it stable in its bracket.

I then seal the edges of the hole with either a refractory mortar or a good fire clay to stop forge exhaust from escaping around the outside of the pipe as that will heat it up very quickly.

The hole itself is tapered to act as a nozzle/flame holder, and that does help keep the heat in the forge. I find with my current set up that the length of pipe between the bracket and forge gets too hot to touch, not a full red heat though. The burner above the bracket never gets too hot to touch with a bare hand.

 

How long is your burner tube? I recall reading that shorter tubes, especially under 8" long, have a tendency to overheat.

James

Share this post


Link to post
Share on other sites

My tube is 12" (plus the coupler). I am currently removing (unscrewing) the tube every time I turn it off, just to make sure the heat doesn't radiate out to the brass. If I am not able to keep it cooler when runningI am thinking I will add a union with another 6" and that should make removal easier and such. I would much rather keep things cool though. Just to be clear, is your taper flaring wider inside the forge or wide side out? Right now there is a bit of a gap around the burner port; I just tack welded it in case I had to change things up. I think I see where I need to be going and will try it out tonight.

 

Thanks!

Share this post


Link to post
Share on other sites

My burner has an 18" tube, so adding another 6" to yours certainly won't hurt.

The outside edge of the hole is large enough to just fit the OD of the pipe and then constricts slightly to prevent the burner from seating too deeply, but it never gets narrower than the ID of the pipe before opening up to the wide end of the flare inside the forge.

Hopefully sealing up the burner port and possibly adding a refractory flare will bring the heat under control for you.

Let me know how it goes.

James

Share this post


Link to post
Share on other sites

Didn't quite get the hour-glass shape I was going for, but I was able to vastly improve things by building in a ceramic reducer. My forge welds didn't hold, but I think it was a surface cleanliness and temp soak issue. Forge got hotter than ever and the coupler didn't even start to glow after a half hour or so at that temp. I'll try again and longer tonight when it is dark enough to see temps better. Thanks again!

Share this post


Link to post
Share on other sites

Update for posterity: I have since streamlined my burner to be a straight tube (with a union in the middle) of about 12". Eliminating the elbow I had and reducing the overall length has helped improve the efficiency a lot, but I still need to find a way to get more air in. I am not blocking off my air at all and still get a bit more propane (flame) coming out the forge door than I would like. A little dragon's breath is good to show you are not oxidizing, but anything more than a little is just inefficient.

Share this post


Link to post
Share on other sites

Taller chimneys produce a stronger draft, up to a point anyway. I was wondering if the same is potentially true for the burner tube and it might be, but I just completed a 12 inch burner for a blacksmiths guild demonstration earlier this month and it didn't seem to have any trouble with airflow during limited testing.

 

So on to the more technical possibility.

It is quite possible that the union in the middle is disrupting the laminar flow of the combined gas stream. Turbulence reduces the gas velocity which in turn reduces the entrainment effect of the venturi, which is responsible for pulling atmospheric air into the system.

I suggest trying a singular pipe anywhere between 12 and 18 inches and see what happens.

James

  • Like 1

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...