RyanMo Posted September 11, 2016 Share Posted September 11, 2016 So I just build my first propane forge and got it going pretty well and it will barely melt aluminum in my crucible but the design should put out more than what I'm getting any suggestions on what I could do to get more heat besides keeping the gas around 7 psi and pulling the burner tip back around 3/4 of an inch! Anything would help! Quote Link to comment Share on other sites More sharing options...
Charles R. Stevens Posted September 11, 2016 Share Posted September 11, 2016 First off, unless your converting raw ore to metal, you are not smelting, second what are you insulating your furnace with, and lastly somthing looks just wrong with your burner set up, it should not be glowing red... Quote Link to comment Share on other sites More sharing options...
RyanMo Posted September 11, 2016 Author Share Posted September 11, 2016 I'm insulating it with the refractory cement and I don't know why the pic did this but it is blue actually @Charles R. Stevens Quote Link to comment Share on other sites More sharing options...
RyanMo Posted September 11, 2016 Author Share Posted September 11, 2016 The burner is a jet torch with compressed air and propane so it burns inside of the fire tube. If that's what your suggesting? @Charles R. Stevens Quote Link to comment Share on other sites More sharing options...
Charles R. Stevens Posted September 11, 2016 Share Posted September 11, 2016 Your digital camera/phone uses an optic that works in to the infer reds spectrum. So hot serfaces look wonky. After insulating with a refractory insulation (cement would be a heat sink) revisit your temp. Quote Link to comment Share on other sites More sharing options...
RyanMo Posted September 11, 2016 Author Share Posted September 11, 2016 Ok so would like the kaowool work for that I guess? @Charles R. Stevens Quote Link to comment Share on other sites More sharing options...
Charles R. Stevens Posted September 11, 2016 Share Posted September 11, 2016 Depends on the temp rating, use two 1" layers, as the flame directly on the insulation will erode it (and replacing 1" is cheaper than 2") You will still want a rigidizer and a radiant reflective coating. Once you do that you should have no problem melting the end of your burner tube... Quote Link to comment Share on other sites More sharing options...
RyanMo Posted September 11, 2016 Author Share Posted September 11, 2016 Ok do you suggest any particular brad of either of these I'm pretty new into the gas forging world so I don't know much about it and I would take all the helpful suggestions I can get! Quote Link to comment Share on other sites More sharing options...
Charles R. Stevens Posted September 11, 2016 Share Posted September 11, 2016 Honestly Mike and Jerry are gas forge guys, I lend more tord solid fuel. Now as this isn't a forge, but a melting furnace I image it will have its own perticularies. Their are castable insulating refractories that Wayne may recomend. Truthfully read up as much as you can, casting can get exiting fast, just one drop of sweat can send molten metal all over. Propper PPE and technich is paramount. Many way I will chech back in the daylight Quote Link to comment Share on other sites More sharing options...
RyanMo Posted September 11, 2016 Author Share Posted September 11, 2016 Also it may be too late but is it going to be bad to put the blanket around the clamor because I have already(stupidly) put the ceramic in the forge and would rather not have to scrape it off and then buy it again so could I just use the blanket with the reflective coating and what was the ( ridgidizer)?? Where can you get that and what is it? Thank you so much for the help sir! Happy forging! @Charles R. Stevens Quote Link to comment Share on other sites More sharing options...
swedefiddle Posted September 11, 2016 Share Posted September 11, 2016 Good Morning Ryan, Please add your location to your Avatar. Welcome to this Forum. Your air /fuel ratio is all wrong, you should be able to hold your hand on the burner tube. The flame is burning back inside the tube, not enough air flow. Are you trying to Forge or melt soft metal? Neil Quote Link to comment Share on other sites More sharing options...
RyanMo Posted September 11, 2016 Author Share Posted September 11, 2016 I would like to be able to achieve both with different heats in the furnace to forge knifes but mainly for casting as of right now and the design that I acquired has the main burn inside of the tube but would it be more productive to cut it off more so you get the majority of the flame in the forge it's self. @swedefiddle Quote Link to comment Share on other sites More sharing options...
swedefiddle Posted September 11, 2016 Share Posted September 11, 2016 (edited) All your heat is in the tube and not in your fire-box, your Air/Fuel ratio is wrong. You have no flame in the fire-box. Turn up the fuel and the air!! you should have some flame coming out the mouth of your fire-box (OK, the center of your brake rotor). You do not want the heat going back to your fuel tank!! turn up your fuel and air. Turn off the burner, light the flame at the inside tip of the burner tube, slowly start the air flow until you have the ROAR!! If the air blows out the flame, turn up the gas pressure at your regulator and relight the flame. You NEED TO HEAR THE ROAR!!!!!! Neil Where are you making a shadow?? Edited September 11, 2016 by swedefiddle Quote Link to comment Share on other sites More sharing options...
RyanMo Posted September 11, 2016 Author Share Posted September 11, 2016 Well this design sucks air in from the base of the fire tube and burns the gas right after the mixing chamber so would it be more productive to cover that hole somehow that way the gas doesn't burn until it reaches the end of the tube or do I just need to cut the tube or what because I understand I'm loosing the heat in the tube but the design it has is made to burn in the tube so would it be better to cover the rear air colum in the back of the tube I guess? @swedefiddle This is the torch https://youtu.be/EVTJk85M5aw Quote Link to comment Share on other sites More sharing options...
the iron dwarf Posted September 11, 2016 Share Posted September 11, 2016 there are people on here who are experts on burner designs for forges ( they could probably tell you a few things about smelting too if you really wanted to turn bauxite into aluminium but you need electricity to do that AFAIK ) personally I dont know anyone who would want to make a forge for bladesmithing that could also be used for smelting as they are so different, a bit like making a sand yacht that will as function as an icebreaker in the artic ! smelting ali is for heavy industry, copper smelting would be easier but is not something a beginner would do listen to those posters above, they know what they are talking about take care when handling the blanket as the fibres are very bad for you, this is a reason for covering it with a ridgizer, to make it last longer and to protect your lungs beware of things you see on youtube, at least 90% is rubbish and more than 50% is dangerous rubbish that can get you maimed or worse. some posters there are notorious for the dumb things they tell people to do Quote Link to comment Share on other sites More sharing options...
Charles R. Stevens Posted September 11, 2016 Share Posted September 11, 2016 From the picture, you can see the hot spot is in the tube close to the end were fuel and air meet, it should be in the furness. As the Iron Dwarf mentioned, anything in YouTube is suspect. I think backing up and redesigning your set up may be the best. Honestly, some times it's best. With proper insulation you don't need a real thick skin to house your furnace, especially with a castable. I also find any burner that runs on compress air to be sketchy. Unless you have a big industrial rotary unit you will run out of air. Blown and naturally asperated burners work just fine. Will/mite work and best practuse are often miles apart. If I was going for will work, I would back off a few thousand years in tech. But for a gas fired unit I would take advantage of the proper tools, materials and knoledge. Quote Link to comment Share on other sites More sharing options...
RyanMo Posted September 12, 2016 Author Share Posted September 12, 2016 iOk guys, so I changed a few things in the burner today and thanks to the help of you guy's comments I can melt aluminum extremely fast! I just would like to thank especially @Charles R. Stevens For the amount of time he spent helping me, being a newb in the business, and due to it the forge is achieving more than what I expected! Thanks guys and I will still take suggestions if anyone has something I would love to hear it! Quote Link to comment Share on other sites More sharing options...
Frosty Posted September 12, 2016 Share Posted September 12, 2016 Welcome aboard Ryan, glad to have you. I watched that video and there are so many things DANGEROUSLY wrong displayed I almost don't know where to start. Whoever thought up that burner was pretty clueless except for adequate basic shop skills. Please just take it apart and find something else to do with the pieces, it's a non starter. Did you notice how much welding he did on galvanized pipe? Did he grind the galvy off so the welds would be competent? Is there ANY mention of proper safety gear? Burning zinc is BAD to breathe and requires, REQUIRES the proper respirator cartridges IF you've been fitted for YOUR respirator. Otherwise it's BAD for you, bad, Bad, B_A_D. Using compressed air CAN be made to work but is a long way from a good way to supply combustion air to a burner. Safety wise do you think it's a good idea to have a RUBBER high pressure air hose attached to a metal melter? Please do some reading in the propane forge burner section here, there are a number of GOOD burner designs offered for the taking. You will have written directions, and dimensioned drawings WITH advise for SAFE operation. Blown propane burners are easy to build and require the same operator skills that mess does but work properly. Naturally aspirated burners require a higher degree of shop skills but don't require operator skills at all once tuned, nor do they require electricity. Neither require a compressor and a second regulator. If you MUST use that burner cut that big honking combustion chamber tube back to where it begins to show red and mount the remains in the melter. Then as soon as you've read a little about REAL burners made by people who actually know what they're doing you'll realize the people who came up with that kludge of a flaming thingamajig have no idea what they're doing. Seriously, you could build a couple T burners for what those brass fittings cost, you have a propane regulator and hose anyway. Heck you have everything, drills, taps dies. Piece of cake to build a burner you could be melting aluminum, bronze, etc. easily. Take a look around for a casting club or one of the online fora. Casting any kind of metal isn't to be taken lightly. A crucible of molten aluminum is a bomb waiting for one of many mistakes to splash you and everything within say 30' with 1,100f liquid metal. Then you get to try putting out all the fires it lit, if you're in any condition or aren't rolling on the ground trying to get yourself put out. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
RyanMo Posted September 12, 2016 Author Share Posted September 12, 2016 Frosty thank you for the feedback! I did find many things wrong with his design so I tweeked it a little and used it once yesterday but I changed the torch completely today to some better specs and it works much better and is just running off of propane. I did cut the combustion tube back about 4 inches as well which helped tremendously and I can melt things much better. Also I decided to not use galvanized steel because like you said it's super unstable and unsafe if you heat it up enough so I just used steel for the first gas mixer but since this I don't even use that due to my ability to get more heat without the compressed air now! Thank you for your comment though and Happy Forging Sir! Quote Link to comment Share on other sites More sharing options...
Frosty Posted September 12, 2016 Share Posted September 12, 2016 Sir me no sirs I'm Frosty to my friends. Sing out when you want to build a forge. You can get away with that melter for aluminum for a while but you REALLY need a proper melter. Not only for economy's sake but safety's sake. A lot of folk have made multi purpose furnaces so they could forge and melt metal and before long most realized the trouble with tools designed to do everything, they do nothing well. There are enough similarities in the two beasts you can use the basic design for both and just tweak them to purpose. Now, pull up a comfy chair the beverages of your choice some snacks and get ready for some serious reading. Just the casting section here is days worth of just skimming posts and there are web fora devoted to casting on many levels. We all learn from our mistakes but there's no good reason not to learn from other folks mistakes. I gladly offer you the the things I've learned from all the mistakes Ive made and heck continue to make. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
RyanMo Posted September 12, 2016 Author Share Posted September 12, 2016 All good points and slowly I'm going to upgrade until have the money to build separate forges for knifes and then one for casting but this was also my first forge so for a start it's not bad and I keep safety at the first priority even if the forge itself is not entirely that but I am very careful with anything but thank you for the feedback! @Frosty Quote Link to comment Share on other sites More sharing options...
Riaan Posted September 13, 2016 Share Posted September 13, 2016 Hi guys, I build a new and improved smelting forge from a old water heater (Giezer in SA). I stabilised the bottom with a mixture of silica sand and plaster of paris to get a flat working base. There after I placed a layer of refractory bricks. Lined the forge with 3 layers of 25mm rated at 1200 OC ceramic blanket. For the lid I stuffed all the offcuts underneath 2 circular pieces of ceramic blanket. This is kept in place by 4 ceramic buttons and filament wire. The burner is something of my own design. I only have butane gas readily available here in SA so after a lot of trial and error I finally got it right to control the gas and airflow accurately. On my initial run I melted an aluminium ingot and realised that my flame is melting my ceramic blanket, therefore I tried installing 2 refractory brick wedges in the path of the direct flame but still keeping my flame in a circular rotation around my crucible (steel in this case) and it worked pretty good. On my second run I tried a couple of brass fittings an old brass ingot which in the end blew up in my face due to phase lock. Don`t worry I was lucky on that one an had learned my lesson. Please raise your comments on pictures added below, I would like to know what you guys think. Regards Quote Link to comment Share on other sites More sharing options...
Buzzkill Posted September 13, 2016 Share Posted September 13, 2016 I'm no expert, but your melter seems to be a heck of a lot better than a lot we see on here. You had me nervous with the plaster of paris at the beginning though. A couple suggestions: Put some rigidizer on that ceramic blanket so it doesn't send lung- damaging particles into the air while in use. Also, a drain hole for when (not if) your crucible fails inside. The the whole thing should be over a bed of dry sand to contain that molten metal when the crucible fails. I can't tell if your crucible is sitting on a plinth to get it off the floor, but that's a good idea. Usually you have to make some channels in the floor so the liquid metal can run under the plinth and out the hole. All in all though, it looks like you have the principles down that will allow you to easily melt metal in your foundry. Quote Link to comment Share on other sites More sharing options...
Riaan Posted September 13, 2016 Share Posted September 13, 2016 46 minutes ago, Buzzkill said: I'm no expert, but your melter seems to be a heck of a lot better than a lot we see on here. You had me nervous with the plaster of paris at the beginning though. A couple suggestions: Put some rigidizer on that ceramic blanket so it doesn't send lung- damaging particles into the air while in use. Also, a drain hole for when (not if) your crucible fails inside. The the whole thing should be over a bed of dry sand to contain that molten metal when the crucible fails. I can't tell if your crucible is sitting on a plinth to get it off the floor, but that's a good idea. Usually you have to make some channels in the floor so the liquid metal can run under the plinth and out the hole. All in all though, it looks like you have the principles down that will allow you to easily melt metal in your foundry. Hi Buzzkill, Thank you for the advice. I hade a discussion with my refractory supplier and he informed me that the ceramic blanket he sold me was a new type (with thinner, longer and more flexible fibres). He said that this new type of blanket should discharge very little if any ceramic particles out the exhaust and that the particles are proven to be relatively harmless. But I ordered the rigidizer as a safe measure and will install as soon as I receive it. Yes the crucible is sitting on a makeshift plinth (refractory brick off-cut) in that picture but I have installed a permanent refractory plinth in the meantime. I forgot to install a drain hole and I will do it before my next firing. I will cut and build drainage channels for liquid runoff and it will land in dry sand (Photos will be posted when complete). On that I still have a substantial amount of silica sand left from my build and also fire clay powder. Your thoughts on those to catch the liquid? Regards Quote Link to comment Share on other sites More sharing options...
Riaan Posted September 13, 2016 Share Posted September 13, 2016 Hey guys, I`m also trying to upload the video I made of my burner for your comments. Regards Quote Link to comment Share on other sites More sharing options...
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