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I am a beginner smith and have some work to do. I am not super educated on gas forges, but I did some research and built one of my own. It is made of a propane tank canister, 2 in. kaowool, and 1/2 in refractory cement (Meeco's Refractory Cement, from Menards). I know that the cheap cement isn't ideal, but I am on a tight budget, and am no expert. My burner is made from 8 inch pipe, a reducer, a coupler, and the propane end (with nozzle) is from an old weed burner. It has a strong regulator built in.

I am open to any and all criticism, thanks for your experience and guidance. I can get some closeups tommorow if you would like. God Bless!


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How does it run?? a pic or two of the flame would be most helpful for everyone her to give an opinion and advice.

your forge shape is interesting, usually the flat part is at the bottom to give you a 'floor' to set things on. would be interesting to see how your variation works.

from what i can see your burner is similar in principle to a reil burner, depending on what you gas flow is like out of that weed burner tip it may work satisfactorily but the pics will tell us more. 

most importantly does it run safely? and does it get metal hot enough for you?

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Thanks for replying. It works pretty good. I don't know at what pressure to run it at. Ill attach some pics, but I usually run at about half pressure, and it brings the metal to a bright orange. I bet if I ran it at full I could get to yellow. However, I don't know if I could budget that so I don't want to waste propane. Also, I don't know if this is frowned upon, but i do use forced air with it. Withiut it the flame chokes. I didn't think my hose was too short but I am here for advice so I'll take it. Any suggestion on a new length? Anyway, here are some pics.First is at half pressure (what I usually run it at) second is full throttle (other than boost). And sorry, there is a small section of ceramic wool exposed, I haven't got to repairing it yet. I know it isnt good for lungs, but by my understanding that much wont really do much to me. Also for the first two pictures I didn't have the air on. Any suggestions or advice much appreciated. -Daniel the Newby





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well that "cheap" refractory is costing you a lot of fuel.  I know that kastolite seems expensive but the money you save in fuel makes up for 100's of times over.   Also IFI sales it in 5# bags for only 15.  That is more than enough to properly coat your forge and do repairs.  https://www.iforgeiron.com/topic/61871-kast-o-lite-30/

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Ok, and a couple more questions if you dont mind, you are helping a LOT. Do I need to by rigidizer for the wool, and if so, where cheaply? Also, I have heard about ITC 100 coatings, but they cost way too much. Do I really need it? And last but not least, at what pressure should I run my forge. Low, quiet heat or high throttle? Anything you have got to say I will gladly listen to.

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Most of us make our own rigidizer, using fumed or colloidal silica. It can be found at most fiberglass supply stores it's used to thicken resins. Make sure you buy the Hydrphylic type it's easy to mix with water. Do NOT buy the hydroPHOBIC type it doesn't like water at all. It's inexpensive, I bought a 8oz. can for IIRC $12 and change. That's a pretty large can more than a pint and I've used maybe 2-3 tbsp. it mixes with water and you spray the kaowool then cure it with a torch or the forge burner. A couple drops of food coloring is a good marker so you know how evenly it's covering. 

ITC-100 is too expensive and not as effective as folk used to think. Buy some Plistex from Glenn it works way better as a kiln wash, another layer of armor. 

The weed burner is a poor forge burner it runs way too lean. They're designed to light weeds on fire so allow lots of oxygen through so there's plenty for the weeds. The second picture is WAY oxydizing . 

Pressure? Your burner adjusts with a needle valve not a pressure regulator. Needle valves control the flow, how much gets past. It's running at tank pressure, figure around 200 psi to the needle valve. Do NOT try to count turns it's open just tune it by eye adjust until you have a good flame. There's no other way to tune your set up as it stands.

I'd recommend you read through Forges 101 for a while then Burners 101. There are hundreds of threads discussing various forges, how they're made work, etc. Same in the burner thread. 

You really need a better burner, even if it gets your steel hot it's going to burn it up, too much free oxygen is blowing through it. 

Frosty The Lucky.


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One more thing. I looked thru some of burners and forges 101, but it was a little to complex for me to read. Is there a condensed place with info in even simpler terms? (I dont know a whole lot about propane, different cements, thermodynamics, etc.) I guess what I mean is there a place for people with limited understanding about gas forge building? Any help much appreciated. God Bless!

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I think any condensed versions turned out to be too complex to be much help. A couple tips. Skim the subjects by title, when you see one of interest skim the threads under it by subject, when you see one of interest skim the messages. That way you only have to read a few hundred instead of thousands. 

Forges 101 and burner 101 are the most recent sections, if you want some perspective take a look at Gas Burners under gas forges under forges.  In places the basics have been boiled down but are buried in layers of subsequent posts.

There are a few basic things to decide before you start planning your forge and burner. You already have a good start on a forge, a few tweaks and it'll serve you well.

What is it's volume in cubic inches? Volume and shape will determine what size and how many burners you'll need. If a forge is long and narrow it'll need more burners of smaller size to get an even internal temperature. 

Then there is what you want to use the forge for, some of us like having a hot zone and cooler zones to allow you to heat smaller sections of your work. Sometimes you don't want the whole thing yellow or it'll get floppy on you when you take a hammer to it. Then there are the guys who NEED even temperature everywhere, say heat treating blades. 

That's just a couple basic types and reasons, there are more, lots  more. 

Not everybody needs a multiple outlet (ribbon) burner, most folks do just fine with one or two single outlet burners. We're getting back to even vs. spot heat. Yes?

The basic ratio where  burners per volume is: one each, well tuned 3/4" naturally aspirated propane burner will bring 300-350 cu/in of well built forge to welding temperature.  Gun (blown) burners can be pushed farther and hotter simply because it's forcing air in mechanically and you tune it as you go. Guns are easier to build but take tuning every time you change temperature. Naturally Aspirated (NA) burners entrain combustion air using the propane jet, "Primary" as the driving force to draw air. They operate on a relatively flat curve, double the propane pressure doubles the combustion air induced into the burner and blown into the forge. Adjust a NA burner is just a matter of turning the regulator or as discussed in another thread, needle valve up or down. However a NA burner is harder to make, it takes some shop skills and tools.

Some NA burners are darned close to rocket science some just tricky others are pretty simple but they're all harder to make than guns, easier to use though and you don't need electricity, the propane "Primary" is all the power necessary. 

There are trade offs to everything. Just do NOT get in a hurry, the only thing rushing does is make your mistakes permanent more quickly.

Ah HAH! Buzz did one of the consolidations! Thanks for the link, I know I'm an hour behind but I'm making a pot of chili for dinner & leftovers and had some chopping and frying to take care of. 

Frosty The Lucky.

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I couldn't find the post on Iforge. The following is a Word doc copy, hope it works.

NUTS, couldn't attach the file only the link to my computer downloaded. Guess I'll try a cut and paste. Sorry about the bandwidth. I'll have to get with Glenn or Steve and see about repairing the Iforge file or something.

Frosty The Lucky.

T Burner Build

The T burner is a naturally aspirated burner built with plumbing parts a few tools and some basic skills. The greatest demand is precision, it isn't a watch but the build needs to be done well for it to function well.

There are basic ratios for making them work properly and once you understand them you can apply them to virtually any size induction device (burner). All the ratios are derived from the throat diameter. The "Throat" is the beginning of the burner tube where it meets the air intake structure. In the case of the T burner where it screws into the T.

The ratios are. Tube length L = 8D (D= Throat Diameter)

Air Intake port area AI = 2 D.

The initiation Set back distance of the jet S = .5 T

The jet diameter was determined by trial and error so I don't have a ratio to offer.

I'm using a ¾" burner as an example in this document.

The parts list:

One each, 1"x 3/4" black iron plumbing T. The first dimension is the "Run" diameter the second is the "Chase" diameter. Looking at the Letter T the "Run" is the cross bar on the top and the "Chase" the vertical. This bit of jargon is how plumbers designate a T and will help you get what you need.

One each, ¾" x 6" black iron nipple.

One each, 1/8" mpt x ¼" flare fitting. This needs to be gauged with the correct drill bit so it can be tapped ¼"-28.

One each 0.035" Tweco mig contact tip. When buying a mig tip, be careful you KNOW what threads it uses to mount to the welding gun. Tweco uses ¼"x28 but other brands use a metric thread, some are available in either. Be SURE of what you buy so you can use the correct drill bit and tap to match!

Lastly is a burner flare of your choice, if you need one. Different applications have different needs. For my general shop forge I use "thread protectors." These are similar to a pipe coupler being threaded from both ends but are NOT intended to couple pipe, they are used ONLY to protect the threaded ends of pipe during shipment. They are often throw/give away things in plumbing supplies but you might have to convince them you aren't going to use them as a coupler.

You can buy stainless steel flares I believe Larry Zoeler sells them as do others. Of course you can make your flares if you wish. No, a bell reducer does NOT make a good flare, they expand much too abruptly and induce bad turbulence. If you're making one you need to observe a maximum rate of increase of 1:12 or a 12% angle as cut with a lathe. The ratio 1:12 means that the beginning diameter will increase once (double) in 12 times its length. For instance a 1" diameter flare will increase to 2" diameter in 12". 1 in 12.


Tools: A drill press is high on my list of most desirable tools for this project. A metal lathe with a 2" spindle pass through is really primo. A hand drill works well with a little different technique.

You'll need a:

          5/16" drill bit.

          1/8" pipe tap.

          #3 drill bit.

          ¼"x28 tap.

          Tap wrench, the large one in a set is much easier to keep aligned and is more desirable.

          To drill the hole to mount the propane jet requires the greatest precision of the whole build. If you have a drill press, drill vise and experience then this is pretty straight forward. However if you don't have a drill vise there's a trick that works very well.

You'll need a 3/4" "Floor flange" and a ¾" "Close Nipple."

The Floor Flange was designed to anchor pipe to a floor like railing pickets. It works perfectly to anchor the T to the drill table. Screw the close nipple into the floor flange and screw the T onto the nipple, make them tight but don't take a pipe wrench to it you just don't want them moving while you're drilling and tapping.

Measure the center of the top of the T carefully. There may be a die/mold ridge in the center and this will help get the mark as close to perfectly placed as reasonably possible. No, a good scale is gust fine put the micrometer away.



Mark and center punch center on the "T." With the drill bit chucked up in the drill press position the T and floor flange on the drill table and clamp it securely. Be careful not to shift it when clamping, checking it repeatedly is a good thing but keep tweaking till the bit rests dead center in the center punch mark.

Put a couple drops of oil in the punch mark and with the press on slow speed, drill the hole to be tapped, 5/16" OR as recommended in your tap and die set.

There is an alternate method if you don't have access to a drill press. You'll need to find a hole saw that will slip into the T and replace, it's pilot bit with the 5/16" drill bit. The hole saw will act as a guide to center and align the drill bit straight down the center of the burner tube. You might have to grind the teeth off the hole saw to get it to fit and move freely in the pipe T.

With the hole drilled unplug the drill press and carefully remove the drill bit Without moving the T!  Carefully chuck the 1/8" pipe tap in the drill chuck. Now against every safety rule I know leave the chuck key in the chuck. <SHUDDER> This is to give you a good grip to hand turn the tap. The drill press is UNPLUGGED so it's not unsafe for this process.


Apply light pressure with two fingers on the feed handle turn the tap into the Pipe T. Do NOT tap to full depth, getting it well started will align everything and you can finish tapping in a bench vise. You want this hole tapped just to the point the brass 1/8"mpt brass fitting screws in tightly without bottoming hard on the shoulder.

Once the tap is well started, loosen the drill chuck and let the spindle rise off. Now you can remove the T and flange from the drill vise and finish tapping for the brass fitting on the bench.

If you used the hole saw alternative to drill the hole go directly to the tap and wrench being careful to tap straight into the T.

The next step is tapping the 1/8" MPT end of the brass fitting to accept the mig contact tip. Very carefully clamp the fitting by the wrench flats ONLY in a smooth jaw vise or use jaw shields you must NOT damage the threads. Apply the tap to the brass fitting being careful to keep straight down the fitting. The larger tap wrench will hold the tap more securely and being longer will give you a better sight line to keep the tap going straight into the fitting. It's also heavier and enough weight to advance the tap without pressure. There is no depth target with this hole so don't worry about going too deep just don't get too carried away. Oil, apply steady turn pressure and frequently back the tap out a half turn to break and free cuttings   


With the brass fitting threaded you can screw the 0.035" mig contact tip in till it bottoms on the shoulder. JUST finger tight and be careful not to bend it or you'll have to remove the broken end and try again.

Now you're ready to screw the brass fitting into the pipe T, screw the 6" nipple into the T and the thread protector on the other and there's the basic T burner, a little tuning and she's ready to go to work.

Oh, you want to supply it with propane? You'll need a tubing flare tool and cutter and ¼" copper tubing. Slip the flare nut from brass fitting over the tubing with the threads facing the tube end. Flare the tubing, slip the nut to the end and screw it onto the brass fitting. Determine where you are mounting the ¼ turn ball valve and using brass adapter from the valve to ¼" flare you attach the now flared other end of the copper supply line. I put at least one turn in the copper tubing envision a single turn of a coil to provide give and adjustability in the line. Pictured is my shop forge showing how I coil the tubing. the manifold with ¼ turn ball valves and adapter to fit the propane hose are top right.




There is an alternative to using the brass fitting and copper tubing. Depending on how you mount your burner it may never be in a high heat area so the rubber propane hose can be connected directly. This is done using a 1/8" scd. 80 pipe nipple. Scd 80 is much thicker than your usual 1/8" nipple, the ID is almost exactly the correct diameter to tap ¼"x28. There is a weld bead and a burr on the ends where it was threaded so use the #3 drill bit and hand turn it in the nipple to chase it clean. Using oil and the large tap wrench tap one end ¼"x28 to receive the mig tip.

The 1/8" nipple will thread into the tapped black iron T and using a 1/8" FPT x ¼" MPT bushing reducer to adapt to the fitting on the propane hose it's ready to attach to the tank and light up. 6-10 psi should be a good starting point, you can adjust the pressure to suit your work and vagaries in homemade burners.

Tuning the flame is adjusting the air fuel ratio by shortening the mig tip. Out of the baggie the mig tips are a little too long so they don't induce enough combustion air. The closer they are to the throat the less air they will induce. To tune the burner you light it and observe the look and sound of the flame. It should have a light blue cone or cylinder in the center with a more transparent darker blue flame surrounding it. Lastly there should be a LITTLE orange feathering on the flames exiting the forge mouth. It should ROAR and loudly.

It should be a little rich to start with so remove the brass fitting with mig tip and carefully cut 1/8" off the end and clean it up. Mig tips are fragile and easy to break, be careful. You can cut the mig tips with a: saw, Dremel cut off wheel, etc. a torch tip cleaning file is ideal for cleaning up the burr in the orifice.

Put it back together light it up and observe. Repeat till it's running clean and hot.

Just a little practice and you can put one together and tune it faster than you can read this . . . almost.


All rights reserved. Jerry Frost





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5 minutes ago, JHCC said:

Linked on this page

Did the link work for you Jon?  I can't open it. It may be a problem on my end though. It tells me it can't be opened but as I said it could be my problem and not the link. 


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The PDF reader I have must not be compatible. I have plenty of PDFs I've downloaded and read all the time. I run into one every now and then that doesn't work. My phone is old and I don't want to download another app so I'll have to deal with it. The weird thing is is that I've seen the instructions before somewhere. Are they posted on Wayne Coe's site? 


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No Daniel, the guy makes a T burner but doesn't actually understand how it works and makes a number of basic mistakes. The still pic on his front page as seen above shows a serious mistake, the mig contact tip is out of alignment so performance would suffer, maybe even be a nonstarter.

John: That link tries to link to the .PDF file on my computer. I don't know what's going on, my Acrobat reader, etc. wants to save it rather than read it. I don't know what's going on. My .PDF files don't show the T burner file saved either. 

This is just weird.

Frosty The Lucky.



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