RichT Posted July 28 Share Posted July 28 Hoping for some help. I have built a two burner forge out of a 30# propane tank. The inside diameter of the forge is just under 7 inches. The burners are Frosty T style with .035 mig tips cut down 1/8 inch. I can get the first burner to ignite, but have to have it at a very low pressure. The other burner will not ignite at all. I'm guessing its not getting enough oxygen, but its only a guess, and I am looking for some suggestions before I start making changes. Any help is appreciated. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted July 28 Share Posted July 28 You need to replace your "T" fittings, which are completely WRONG, with the right fittings. Your present fittings have the same size center exhaust hole as the two end entrance holes; it is supposed to be at least one size smaller than the two entrances. Why? Because this little bit of constriction increases the swirl that the opposed entrances create. This swirl is needed to properly mix the incoming air with propane. So, your present fittings will never work worth beans!!! Quote Link to comment Share on other sites More sharing options...
Frosty Posted July 29 Share Posted July 29 Ditto Mike. The plumbing Ts need to be 3/4" x 1", the 3/4" mixing tube screws into the drop, the two 1" runs are the air intake. This allows the burner to induce sufficient combustion air for a larger propane jet, a 0.035" mig contact tip. The mixing tube to bore ratio is 8:1 meaning you multiply the ID of the pipe x 8. Do not bother miking the id of water pipe it's not THAT accurately made just use the as sold dimensions. The length of the mixing tube on a 3/4" T burner is 8x.75" = 6". I see you tried to use the same fittings on your forge I use on mine. The difference that makes yours incorrect is, you are plumbing to rubber hose where I'm plumbing between a multi burner manifold to the burner with 1/8" copper tubing. You'll probably have to lose the fitting you screwed into the Pipe T and redrill and tap it for the mig tip. Oh heck, I'm not going to try writing this from memory nor am I going to look up my T burner instructions for you. It's in the gas burner section probably still pinned to you don't have to go looking. Follow the directions that does NOT include Copper tubing! Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
RichT Posted July 29 Author Share Posted July 29 Thanks for the response. I had to check to make sure, but I actually did use a 3/4 x 1" T. I pulled the directions from the site and tried to stick to them up to the manifold. Pardon the welds. It's a group project with one of my kids Quote Link to comment Share on other sites More sharing options...
Irondragon Forge ClayWorks Posted July 29 Share Posted July 29 It's funny the first picture looks like the sizes are all the same, probably just camera angle or something. One thing I would check is to make sure none of the Teflon tape has gotten into the orifices of the mig tips. Another thing is what regulator and propane tank are you using? The new BBQ size tanks have a flow restrict-er in the valve. I can't control the wind, all I can do is adjust my sail’s. Semper Paratus Quote Link to comment Share on other sites More sharing options...
RichT Posted July 29 Author Share Posted July 29 I pulled the mig tips to make sure it is clear. Its currently a 20# tank with a high pressure regulator. It seems like I'm getting plenty of flow, as when I try and light it with a propane torch the flow is pushing the torch flame. I can get one of the burners lit, but I have to turn the pressure way down and only partially open the 1/4 turn valve I have in line. Quote Link to comment Share on other sites More sharing options...
Frosty Posted July 29 Share Posted July 29 Is the regulator "high pressure" or a 0-30 psi high flow? The highest the burners in my forges will run is 12-13 psi. The 2/3 T burner is a low pressure/velocity high volume device. Do you have a gage on your regulator? If so what psi are you running? How about a pic of the whole forge from propane tank to burners so we can get a look at your fuel circuit. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
RichT Posted July 29 Author Share Posted July 29 The regulator is actually a 0-100psi, as that is what the propane supply place had. I've had to get the psi below 5 to get the one burner to light., but that was with the 1/4 turn only partially open. The photos are attached. I can swap out for a regulator that came with a devil forge furnace if that is worth trying. Quote Link to comment Share on other sites More sharing options...
swedefiddle Posted July 29 Share Posted July 29 Good Morning, Do you have doors for the ends? You need room for a vent/exhaust, you also need to contain the flame inside. After you get it started, you may find the single bottle freezing up, get ready to connect 2 or 3 bottles in parallel. Welcome to the world of Learning. Pay attention and make notes of what works and what doesn't work as good. Don't be afraid to try little changes/adjustments. You can use your fingers to create restrictions for your air inlet. Try, Try, Try. The only failure would be walking away. Try little things!! Neil Quote Link to comment Share on other sites More sharing options...
tinkertim Posted July 29 Share Posted July 29 Hi RichT, Another thing to allow for when using 2 or more T-Burners in-line is turning the air intakes so that they do not face each other and potentially affect each other's air intake flow. You currently have them both set East-to-West. Try turning them both North-to-South to minimise unwanted interactions. Hope this helps. Tink! Quote Link to comment Share on other sites More sharing options...
The Jeff Posted July 29 Share Posted July 29 When it does light, what color is the flame? Is the flame blowing off the burner? I can't help with this but that might be helpful information to others. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted July 29 Share Posted July 29 My bad about the "T" fittings. Lesson learned I like the work you did on the insulation and flame surface. Ending up with a "D" shaped interior inside a cylinder is smart. It won't end your burner problems, but turning the air intakes ninety degrees would probably help. Hang in there; things will all work out. It might help to figure out what is going on, if you change out the MIG tips for smaller sizes... Quote Link to comment Share on other sites More sharing options...
Irondragon Forge ClayWorks Posted July 29 Share Posted July 29 I really think the problem is in the tank shutoff valve, which all the new exchange tanks like Rhino have the flow limiter. You can try and opening the tank valve slowly, if opened too fast the limiter kicks in. Also have the regulator shut off and open it slowly. Here is a thread on them from the Bladesmith's forum. https://www.bladesmithsforum.com/index.php?/topic/40609-propane-flow-limiter/ I had that problem with our single burner forge until I found some older tanks with the valve that does not have a limiter. One way to tell is the shape of the handle the valves with a 3 wing handle have the limiter, a round handle are the old style without a limiter and ours work fine. I can't control the wind, all I can do is adjust my sail’s. Semper Paratus Another thing is turn the quarter turn valves off then slowly open them while lighting the burner. Quote Link to comment Share on other sites More sharing options...
Frosty Posted July 29 Share Posted July 29 Good call Randy, his tank has a 3 wing handle on it. Try it Randy's way, it's a good suggestion and remember the 1st rule of trouble shooting. Change ONE thing at a time and test the results. Changing more than one leaves you not knowing what did what. Flow limiter valves on propane tanks has been a problem since they came out! Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Buzzkill Posted July 30 Share Posted July 30 Low pressure is not his issue. On 7/28/2024 at 8:27 PM, RichT said: It seems like I'm getting plenty of flow, as when I try and light it with a propane torch the flow is pushing the torch flame. If it was a low pressure issue he'd be getting burn back in the mixing tube or similar results. This sounds like blowing the flame off the end of the burner. If it were me I'd be looking at axial alignment of the mig tip and the mixing tube. Just for troubleshooting purposes I'd also cover one of the inlets on the T and then partially cover the other with my hand while trying to light it. If the flame stays on the end of the burner with most of the intake air blocked off, but blows off the end of the burner when you remove your hand then at least you know for sure it's not a low pressure issue. From experience I can say that without a flame retention feature on the end of the mixing tube some T burners are difficult to keep lit until the forge starts glowing. While I don't necessarily recommend a 3/4" to 1 1/4" reducer fitting as a permanent flame retention feature, it can be useful in troubleshooting. Check the easy things first. Quote Link to comment Share on other sites More sharing options...
Frosty Posted July 31 Share Posted July 31 Flow limiters are not a low pressure issue, it's not operating the device correctly issue. Opening the shut off valves SLOWLY prevents them activating. And NO, do NOT use 1/4 turn shut off valves for flow limiters! It will erode the seats in the valve so they leak. Use needle valves for flow limiters, it is what they are made for. From my experience T burners are easy enough to light and keep lit if built and tuned correctly and you open the valves slowly. A thread protector is all the flare necessary. If that. I'm not going to try trouble shooting burner problems further until I see some pics of the problem. There is no way I can tell what's going on from a description by someone who doesn't know what to look for or how to read the flame. Until then we're just guessing. I'm not dissing anybody but I'm not going to make random guesses and hope. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
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