ForgeNub Posted March 9, 2017 Share Posted March 9, 2017 Hey Everybody, I just barely started getting into the forging game, and built my own forge. I am actually on my second design since I believe my first was WAY too big, but even now with the same venturi burner set up and a 240 cubic inch chamber I am still getting huge flames, no real concentrated burn and the forge is only getting up to about an Orange heat. The first forge I built was...ambitious and not well thought out and came out at 906 Cubic inches, it would get to orange too but took forever to get there and heat anything. Using a .030 mig tip, have 0-30 psi regulator with gauge as well as an in-line needle valve for further adjustment. No matter what I do it looks like a camp fire inside the forge, no real sound other than hissing from the orifice and to even try to control the dragon's breath I need to adjust the needle valve to almost full closed to not have 12" flames kicking out the front and back of the new mini forge. Any ideas? I knew the first one after taking 8-10 hours to forge tongs was just too big to run on less than like 3 burners, but curious why the heat hasn't improved with a better built and smaller forge. Thanks for any assistance in advance! Quote Link to comment Share on other sites More sharing options...
Crytin Posted March 9, 2017 Share Posted March 9, 2017 Your air mixture sounds to be off. Typically with gas burners of any type, if your flames are yellow, you're getting too much gas in your fuel/air mixture. Make sure your air intake ports are appropriate for your mixer Quote Link to comment Share on other sites More sharing options...
timgunn1962 Posted March 9, 2017 Share Posted March 9, 2017 Too much gas, not enough air. Try a .023" MIG tip and see if it gets hot enough to do what you need it to do. Quote Link to comment Share on other sites More sharing options...
AnBello Posted March 9, 2017 Share Posted March 9, 2017 I would say that some pictures can be quite helpful. Pictures of your forge, your burner, and if possible, your forge running at night, so that we are able to see the dragon's breath and the flame profile. Quote Link to comment Share on other sites More sharing options...
ForgeNub Posted March 10, 2017 Author Share Posted March 10, 2017 I rebuilt the orifice and got a smaller size MIG tip think I got it nice and running properly now!! Getting up to what I think welding heat, glossy yellow with some scale on the piece. Running at 10 psi and have a proper jet don't have my itc100 yet am waiting to coat my current refractory once it shows up. Quote Link to comment Share on other sites More sharing options...
Frosty Posted March 12, 2017 Share Posted March 12, 2017 Welcome aboard Nub, glad to have you. If you'll put your general location in the header you might be surprised how many of the Iforge gang live within visiting distance. We need some details to be able to help you in any meaningful way. It's burning too rich is obvious. Telling us you're using a 0030 mig tip is only a small part of the equation. What is the basic type burner? What's the tube diameter and length. How large is the intake area? Where are THE PICTURES! These things are easy to make and tune but we gotta know enough to help or you're on your own. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
ForgeNub Posted March 15, 2017 Author Share Posted March 15, 2017 K so, I went out on a limb and made a few changes to the forge after being told it was all about Air/Fuel Ratios. Burner Set up is an 8 x 3/4 " Tube to a Stainless 1 1/4 x 3/4 Bell Reducer. Orifice is now made with 1/2 inch street elbow with brass plug tapped with a .025 MIG tip, held in place by set screws tapped into a 2 x 3/4" Bell reducer for air flow. 1/2" Pipe all the way back with a bunch of reducers down to 1/4" Needle Valve to a quick connect 6 foot hose to my 100 lb propane tank. Used to look like a campfire because I think the plug I had tapped for the MIG tip wasn't even cast straight it was all skewed and made it hard to center, so after rebuilding that It came out great, instead of a contained campfire, I now have a mini jet engine! Thanks for the help guys, heres some pics of the current forge set up after taking your advice. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted March 15, 2017 Share Posted March 15, 2017 There can't be much wrong with your forge, or its burner by what I see in the last photo; just keep going and tweaking your results; you are a good way down the right track. Start thinking about getting better control of your exhaust opening, and using a good heat reflective finish coat inside the forge. Quote Link to comment Share on other sites More sharing options...
Frosty Posted March 15, 2017 Share Posted March 15, 2017 Looks like a fine working forge to me too. Ditto Mile's suggestions, closing the openings off appropriately to the work will only increase the efficiency and temperature till it hits the limit of propane / air flame. Kiln washing it will increase efficiency and effectiveness. There is a difference you know. Kiln washing will also make it much more resistant to HOT chemistry like borax fluxes. I'd REALLY like to see the LONG pipe sticking horizontally off the burner replaced by a much shorter one. That long creates a large moment of leverage against the fitting on the burner so even a small bump on the hose can break it off. Your propane tank is quite a ways from the forge and the hose is swinging between them. Eventually someone WILL walk into it or drop something on it. Even if you never let others in your shop then you'll drop a piece of stock, ladder, sub sandwich or something on it. Mr. Murphy will NOT let an opportunity like that rest forever. Honest, I know, got a number of T shirts. It's a good looking forge, well done. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
ForgeNub Posted March 16, 2017 Author Share Posted March 16, 2017 Thanks for the tips guys! I did weld a couple pieces of flat 3/8' bar stock to the rear opening to block it off and a porch on the front door for stock as well, I have a Pint of ITC100 coming, was horrific to try to find any in stock but ended up getting some from www.anvilfire.com and it will be here beginning of the next week, the guy there said i would have no problem coating my current cement with the ITC and to also coat a large portion of the Kiln shelf floor i used as well, but that I should leave the rear of the forge floor uncoated to help release any moisture that may be built up after cooldowns on next fire up? I've read VERY little about Kiln washing, how does it work and where do I get it? There is a pottery supply store near my home that I can use if they have any though. Also - Any ideas on what I should do about exhaust opening? Like maybe a hinged door flap insulated that can create a better seal? Also having trouble developing a choke plate or something for the burner, the opening is so big with 2" x 3/4" it won't start up unless i block off the venturi because of so much air flow but once its hot I can remove it and it runs great Quote Link to comment Share on other sites More sharing options...
Frosty Posted March 16, 2017 Share Posted March 16, 2017 ITC-100 is a kiln wash and one of the better ones for gas forges. Start it by throwing a little wad of burning paper in the forge then CRACK the 1/4 turn valve on SLOWLY and open it to full gradually. This is how I light my burners and they're tuned correctly. I don't see anything in the pics of it running that says it needs a choke plate, it's running very nicely. It ain't broke DON'T FIX IT! Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted March 16, 2017 Share Posted March 16, 2017 There has to be an opening for the exhaust gases to leave by. What we are talking about is being able to make the opening as small as you can get away with. Also, you don't want radiant energy escaping along with the exhaust gases. The easiest answer to both questions are hard brick pieces that can be used as a wall with a variable size central opening. The wall can be moved closer or farther away from the forge to allow just the right amount of gas to escape for how ever high you turn up your burner(s). Use some of the ITC-100 on the side of the brick that will face toward the forge. Quote Link to comment Share on other sites More sharing options...
ForgeNub Posted March 16, 2017 Author Share Posted March 16, 2017 12 minutes ago, Frosty said: ITC-100 is a kiln wash and one of the better ones for gas forges. Start it by throwing a little wad of burning paper in the forge then CRACK the 1/4 turn valve on SLOWLY and open it to full gradually. This is how I light my burners and they're tuned correctly. I don't see anything in the pics of it running that says it needs a choke plate, it's running very nicely. It ain't broke DON'T FIX IT! Frosty The Lucky. Ahh see my valve isn't a 1/4 turn, its a 1/4" Needle valve that allows for very fine adjustments, i've fiddled with it when trying to light to see if I can get proper Propane pressure to not overwhelm the chamber with air flow but it seems to do nothing, to be honest, I cut the bottom off of a cheap peanut can and cut a slot to go around the top tube above the orifice it slides on and I just press it down a bit and it fires, sputters for a minute then starts running smooth and once i see yellow flames coming out of the forge opening I pull the plate off and it runs smooth afterwards. So i've basically just started leaving the valve full open and sticking a blow torch in the front when I light it and once the plate is in place I'm good to go. 10 minutes ago, Mikey98118 said: There has to be an opening for the exhaust gases to leave by. What we are talking about is being able to make the opening as small as you can get away with. Also, you don't want radiant energy escaping along with the exhaust gases. The easiest answer to both questions are hard brick pieces that can be used as a wall with a variable size central opening. The wall can be moved closer or farther away from the forge to allow just the right amount of gas to escape for how ever high you turn up your burner(s). Use some of the ITC-100 on the side of the brick that will face toward the forge. I could possibly devise something that is like an actuator with a split door for the back so I can adjust the width of the gap at the back then use an ITC coated brick to block off that gap? Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted March 16, 2017 Share Posted March 16, 2017 I am describing the front opening. Lots of guys use doors on a back opening. Quote Link to comment Share on other sites More sharing options...
Frosty Posted March 16, 2017 Share Posted March 16, 2017 Put a 1/4 turn ball valve right after the regulator! Buy it at a HVAC supplier and get one rated for propane. Forget the half donkey wonky fixes, you're trying to figure out things that are a mature well refined and developed technology for batter than a century. Just go with the system that works. There are a lot of versions but all boil down to the same basic thing. Your burner is working very well WITHOUT A CHOKE! Putting one in the circuit WILL MESS IT UP! Just plumb the gas supply correctly. Tank valve is ONLY the master valve. It is too slow to use as an emergency shut off ad just cracking one to act as a flow meter WILL erode the seals in the tank valve so it leaks. Do NOT crank hard on it turning the gas off that too ruins the valve seals and costs you money replacing the valve and leaked gas. Next in line is the regulator a high volume 0-30psi is the currently most available suitable PROPANE regulator. Do NOT use an acet regulator unless you have one of the new propane rated ones, even then they aren't very high flow and not so good for multiple burners. Old acet regs will have the diaphragm and or seals eaten out of them by the propane. Never use an acet reg used for propane for acet again. That's a recommendation from my local welding AND propane suppliers. I've run an "All State" oxy propane torch for better than 30 years now so I heard the sermon a number of times. A gauge is only good for making it easy for YOU to repeat temperature and atmosphere conditions in YOUR forge. What works for you doesn't make much difference to anybody else, it's not like you're using commercially built burners half a mile away. The gauge goes next in line after the regulator so you can read it as you adjust the regulated psi. Most regs have a female fitting for a gauge but not all, an appropriate street T is the better fitting in the circuit. Next in the circuit is the propane rated 1/4 turn ball valve. This is the working valve and emergency system shut off. Being 1/4 turn from full open to full closed means you can shut the gas flow off almost instantly in an emergency. They are also made so their position is intuitively obvious. The handle is a BIg flag, if it's in line with the circuit, say hose for purposes of discussion, it's OPEN if the handle is perpendicular (cross ways) the valve is CLOSED. You can see this from at least 50' away. You can close the valve with a fast slap or even a thrown glove. Putting it directly behind the regulator means it's as far from a fire as it can get and be in the circuit, it also shuts off the most circuit that is practical. Next in the circuit is the hose. Use as FEW and close fittings as possible! How you plumb the final gas supply depends on how your forge is configured. My forges tend to be multiple burner and my old soon to be salvaged out 4 burner shop forge's burners are vertical top mounted. I rarely run more than one so you'd better believe they chimney heat, shutting them down will turn the tubes blue and the copper final supply tubing is heat patina darkened. Fire safety is why I use 1/4" copper tubing for the propane supply circuit attached directly to the burner. If your burners are horizontally aligned then a rubber hose can ge attached directly to the burner as it's well away from the 2,000+ temperatures in a forge's immediate vicinity. Try HARD not to use long pipe nipples in the final supply circuit they make it much too vulnerable to breaking at a fitting! Hoses are trip hazards everywhere and the hose between the tank and final supply is especially susceptible to folk getting tangled or having something dropped on it. If the hose is connected directly to a regulator it's a pretty tough connection, you can drag a foll 100lb. propane tank behind a pickup truck by the hose without it breaking. I've only seen that one once and we replaced the reg and hose on GP. Still it didn't fail. If however there was a 10" long pipe nipple between the reg and the hose the increased leverage would've at minimum broken the nipple and possibly split the regulator. You see excessively long pipe nipples in the final supply circuit in a LOT of vertical top mounted burners. The ones on "Forged In Fire" are perfect examples. The reason is to get the hose away from the forge but how they do it increases the probability of something or someone giving the hose a big jerk and breaking the nipple or ripping the fittings out of the burner assemblies. I use copper tubing now even though the burner tubes are horizontal and well away from heat hazard for a couple reasons. First I have the copper tubing, tools and fittings at hand and have been doing it this was so long it's habit. I only consider metal tubing in the final propane circuit a real safety issue for top mounted vertical burners or burners where the rubber hose can come close to the heat. Minimizing the hose trip hazard is operator responsibility. With just a LITTLE thought you can place the tank where folk are unlikely to walk or carry things and still be close enough to kill the gas flow in an emergency. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
WoodnMetalGuy Posted March 16, 2017 Share Posted March 16, 2017 19 hours ago, ForgeNub said: Also having trouble developing a choke plate or something for the burner Here's what I've got for a choke plate. I'll be trimming the threaded rod that the plate is on, don't need it so long. One weld to attach the threaded rod to the side of the coupling nut, and a braze to attach the nut to the choke plate, other than that it all threads together. -- Dave Quote Link to comment Share on other sites More sharing options...
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