Mikey98118

Frosty, I see no stuck foot problem. First, let's talk burner versus torch. Manufacturers and dealers usually call anything running out in the open air a torch, so I could get away with calling all my burners hand torches, since they are all tested for performance in the open air, and work well as hand torches. But they are all designed to be primarily used in heating equipment, so it is less confusing to call them burners, whether hand held, or installed. Theoretically, we are talking about an all primary combustion zone torch/burner. However, the burners must be built correctly, and then carefully tuned to make that flame. Most readers can't resist "doing things their own way; just some 'minor' changes, you know?" Then too, an even larger percentage of readers don't follow directions about tuning the burners correctly, which begins with distance of the gas jet to the entrance of the mixing tube opening (; once that is done, the overhang on the flame nozzle is CRITICAL to burner performance, especially if the operator desires complete primary flame combustion. Note: I called the elongated gas jets n my first book" accelerators" for good reason , but gas jet is the accepted term, and the difference they make is now accepted far and wide, so "gas jets" they are from now on. If these two parameters are met. complete combustion from a neutral primary flame will result. In the real world this rarely happens, so I'm used to seeing a wisp of secondary flame most of the time. As a hot rodding mad scientist monomaniac, this disturbs me, but it makes no practical difference at all; especially when these burners are installed in heating equipment, because their flames actually change and improve inside a forge or furnace; you can see them elongate and their outline becomes smooth, instead of slightly jagged, as they appear in the open air. I believe it is back-pressure from the equipment the burners are installed within that improves the flames, and although I had always assumed the refractory lining absorbing sound was the reason they ran so much quieter inside heating equipment, it just now occurs to me that the change in the flame is a more likely reason for this. Burner noise is created by turbulant flame; the smoother the flame the quieter it is. I never tumbled to that obvious conclusion before, because I hadn't experienced the drop in flame noise from Vortex burners, which make much smoother turbulent flames than my tube burners produce. To explain my claim of quieter burners, we only have to remember that laminar flames, whether from air-fuel Bunsen burners, or from torches make so little noise that the sounds we associate with either tool are simply the sounds of gas flowing into the mixing tube(s); sounds which are normally drowned out by the flame noise from turbulent burner flames. Don't you just love the obvious? Conclusions, floating around right under your nose can take years to be sniffed out; this one lay dormant for a decade and a half! That should read oxy-fuel torches I think most readers falsely assume that tuning is done with the sliding choke. What the choke is really for is cold start ups, when the flame nozzle isn't heated enough to assist with fuel combustion, and for running the burner rich at times, which otherwise couldn't be done with one of my burners.

I just looked up metalbestos pipe and a whole raft of stuff I've never seen before is on the web now, including oval shaped chimney pipe, and ceramic fiber insulated pipe.

Frosty writes: "Another gas forge I really like is a SS stove pipe shell. The stuff is a little expensive but not unreasonable, you don't need special tools to work it: ruler, red pencil, tin snips, drill, bits and a pop rivet gun is your tool kit. Everything else is off the shelf. One last handy little bit about stainless steel you'll like Mike, you're as selfish about heat you've spent good money to generate as I am. Stainless steel has a high IR albedo. It reflects heat." I thought about using one of those, along with a 1" inner layer of ceramic fiber blanket (at the rate my burners eat up stainless steel flame nozzles, I wouldn't want to risk exposing a thin inner liner of stainless to flame impingement from one of them). And since we've both mentioned them, we should warn people to wear at least a double string dust mask when working on the pipe, and thoroughly vacuum the work area afterward, since it's lined with asbestos. But, I think most people would not want to spend the money for such a fancy shell with so many tin cans in the world; wouldn't stop me though. Yes, that would make a nice Formula One piece of heating equipment...

Well, now I've got a problem. This site won't accept my attempts to post my chapter notes for the 3/8" burner. How do I work around this little glitch?

Not if it's a naturally aspirated burner; they have long turn-down ranges.

I'm a little torn, between advising newbies to start with a brick pile forge, which certainly has endless virtues, and advising them to start with a miniature forge coffee-can or two gallon refrigerant cylinder sized, which is super portable and easily stowed beneath a workbench, and will always find use even after they decide on what their personal version of the "perfect forge" is. I built both and still can't decide, which is better; maybe it just comes down to what a guy thinks is the most nifty? I think for some of us its like collecting cars; more a case of greed than common sense

Venturi, It is hard to tell for sure from the photo, but that looks like an armored cable covered gas hose leading to your burner; I heartily approve of that stuff used that way.

Frosty, You also asked about air opening position and size. I made my slots about 40% larger (when the area of all of them was added together) than the area of the flame nozzle; this turned out to be unnecessary, which became obvious when the burners were tuned As the choke was opened on these burners it would reach a point of maximum efficiency before coming even with the front of the air openings. I was being very conservative in my construction methods, because I wanted "some of everything to spare" when readers built my burners, which brings us to your other question... All air openings were laid out in odd numbers (3, 5, so that they were never positioned opposite of one another. so as to insure that each entering air stream was less likely to interfere with another stream; I thought that necessarry becuase spin was imparted to the air streams. I also used more openings than needed, to ensure smooth operation (longer thenner openings tone down the performance a bit more than shorter wider openings do). Of course the optimal number of openings on any jet-ejector burner is three, but I was a lot less concerned with maximum performance than in ensuring maximum stability in an entirely new burner design. After years of retrospection, I would not recommend more than three air openings on these burners; but that is now; not then. The difference between what we picture in the mind's eye and what happens is the reason for experiment, but looking back on it all, I am still "taking some of my mental pictures" on faith; I did enough experiments to design good burners, but not enough to prove everything I 'know' on the subject. After two years the publisher wanted a finished book. I probably will run smoke test, etc. on the Vortex burners, though.

Okay all, I will post my book notes on the 3/8" burner, which can be used in a Coffee-can size furnace by turning it down most of the way, and is quite capable of heating a properly built Freon cylinder forge, to yellow-white heat. This chapter is text only; there are no drawings or photos in it yet, but those of us who are involved in building these burners can post photos, and relate our experiences as we go. And, of course, you all can corner the author and insist on further explanations as we go. Lets keep it all on this thread for now, and when we are finished with the subject, it can be given its own thread; maybe along with better instructions on constructing miniature forges. Forging Carver, It would be silly to break apart your forge's filler at this point; better to build your burner and use it to test out whether or not the burner port is too close, instead. Also your port pipe isn't placed at the right angle to get good swirl, which means the combusted gases will exit the forge faster; that can cost you as much fuel as poor insulation This also gives you something to use while you collect the materials to insulate the forge with the correct way, next try. This is also your opportunity to place a high alumina kiln shelf in front of the forge opening at a variable distance, and use it as a baffle plate. You've already paid in labor to put that insulation in it, so put it to some good use as a test bed, before breaking it down.

Frosty, Well, that gets us back to brick pile forges again; after all, I can't think of any other forge that would allow someone to play around with size, shape, and completely different burner systems. So, to the list of their virtues we can logically claim they are the best (self) teaching tools

Harry, My answer was expert, but also flippant; so I apologize for that. Adding charcoal won't just create a reducing atmosphere in the forge; it will create a carbonizing atmosphere, which is no big deal, unless you've gone to the expense and trouble to paint a high-emissive coating in it, in which case that nice rich carbon source will do a wonderful job if covering it up. I learned this lesson the hard way by using a propane additive that was meant to be used in an oxy-fuel flame; not air-fuel. Thereafter, I had lousy performance for the several heats it took to completely burn that coating away (ITC-100 is too delicate to be wiped clean). Also, all you have to do in order to know your flame isn't oxidizing is look for any trace whatsoever of secondary flame. So long as you can see the nearest trace, than your flame is still reducing or neutral; not oxidizing.

Probably; but remember you'll be working right next to a forge, so it probably won't be all that cold.

Frosty has it right

Frosty asked "Is Rex still machining his burners from billet?" I haven't communicated with him in nearly fourteen years, and have no interest in his problems. You know those little curled arrow symbols at the back end of airplane wings in drawings of what happens to air flow over one of them? Imagine for a minute that if you can get that much drag from what, for all practical purposes is a knife edge, with the air running past it in parallel on the bottom side, and at a very close angle on the top side, how much more drag you get with air running past an edge at close to right angles. How much drag is in direct proportion to how fast the air flow is, but naturally aspirated burners only use tiny forces to induce air flow, so a little bit of drag goes a loooooong way in interfering with burner operation. Round edges produce more drag than straight edges, and a row of holes has a whole lot of round edges. So, you would naturally assume that reducing those round edges down from many to just two in a slot shaped opening would get rid of all that drag, yes? NO; it gets rid of a lot of drag, but one of those round edges is right at the mixing tube entrance and just forward of the gas jet; the amount of drag a round edge creates there is a REAL BIG DEAL! Even at the back of the air opening you can see a definite performance difference between straight edge and curved. So, I cut out rectangular air openings, but didn't get as big of a performance leap as expected...until I went the extra mile and beveled the forward and rear faces of those rectangles to knife edges. it was like driving down the road, and finally remembering to release the safety brake; big difference. Orange and red streaks are not uncommon in high speed flames coming out of a stainless steel nozzle. I had occasionally noticed them in one of my burners, but paid them no mind, until a couple of glass artists posted a question about it on one of the casting groups; I invited them to send me their burners (with return postage prepaid). The burners were correctly built and worked beautifully, but their flames made a lot of red and orange streaks. The flame nozzles were also highly reflective. They had used #304 stainless. On a hunch, I replaced the nozzles with #316, and presto; no more streaks. I will have to visit the Hybridburners.com site and look at the flames; that's what I get for throwing in an out of date memory...suppose we need to refresh them every decade or so It is fine that you're interested in burner mechanics, but just remember that your burner has probably been built by more blacksmiths than all of mine. It takes about eight hours and a lot more money to build a high speed tube burner, or over $200 to buy one; that can be discouraging for people just starting out. I'd much rather they built an easy to construct burner and come play in the pool. I get to lure more people down to the deep end that way

Actually, a bean can forge would use a 1/4" burner. A 3/8" burner would only work even in a coffee can forge by turning it down most of the way. There is something to be said for using some kinds of jewelry torches in miniature forges, but you must be careful to keep them from overheating. Forging Carver, If you want to get hold of a two gallon size helium cylinder or non-refillable refrigerant cylinder and build a proper knife forge, I will post instructions on this forum for building my latest (generation six) high speed tube burner.

I suppose people can find some benefit in almost anything, but if you should ask whether or not there is any practical benefit the answer would be no.

Frosty, BTW, It is no surprise that you have difficulty with the idea of complete single primary wave combustion; everybody does to begin with; that included me. Back in 2002 Ron Riel requested that I teach Rex Price all about my burners, because Rex wanted to make burners for sale, and Ron had wanted someone to offer g-o-o-d gas burners for sale for some time; this is how the three of us came together and Hybrid burners were born. After about two months of emailing back and forth, Price sent me his version of my burner for evaluation; it was hilarious...and awesome. The hilarious part was that he built it two feet long! The awesome part was that by exchanging my rows of holes for slot shaped air openings he had completely changed the nature of the flame it put out; there was no secondary flame present at all! Anyone who has run oxy-fuel torches will immediately understand how mind blowing that is to see in an air-fuel flame. I cut down the various parts of the burner to the minimum length it could work at, and sent it back to him. In following months I sent him models for all but his smallest burner, and let him build finished versions of them. We discussed the technical details of my 3/8" "pocket rocket," which he shortened to "Rocket" burner, but I never sent him that model, as we had a falling out about then. Anyone can see total primary flame combustion, by going to the Hybridburners.com web site. What you don't get there is the feeling of magic that only comes from seeing that flame exit a burner that you built with your own hands. I went Price one better, after doing research on why an air slot performed better than a row of holes, by making rectangular openings, which were beveled for and aft for laminar flow; this final improvement sped up mixture flow so much that the burners no longer needed a built in funnel shape, allowing me to cut air openings into a single tube structure; it also allowed tapered flares to be replaced with the more effective tube and spacer ring found on my burners. Most importantly, it enables the burner to put out a neutral single primary combustion wave. Hybrid burners put out lightly oxidizing flames, which is why they are dark blue, instead of light or medium blue. Price is not one of my favorite people; I took a lot of abuse over the first few years from morons who assumed that I stole his burner design, and then made a few "insignificant" changes to it. But no one can take this away from him: Rex Price made the first all primary combustion flame come out of a fuel-air burner; one look at that flame completely changed my thinking about burners, and the rest is history.

Frosty, I do make up some terms to describe equipment built, and you have every right to be suspicious of them, and ask for their justifications; "Cage" is the term I used for the outer structure which holds my Multi-hole glass furnace in chapter 10, in order to distinguish it from "A" frames (the most common way to suspend a tilting furnace), and square frames used to make the forge cart and its 6" thick insulated table top. Making up terms for things that aren't easily described correctly with usual terms is an inventor's privilege; one that should never be used without necessity, and which is quite often ignored or even overturned by the public. My fifth generation high speed tube burners are now called Mikey burners; a completely unintended consequence of my own actions, and a good joke on me However wave fronts is a term invented by combustion engineers; perhaps to reflect the nature of flames as semi-controlled explosions. Also an explosion's wave front within a gas filled tube (of an extended length; usually nine feet) is the phenomena which is electronically timed, to determine a given fuel's flame speed. Flame speed is one of the factors used to determine adiabatic flame temperature; the maximum (and utterly theoretical), flame temperature of a given fuel. According to combustion engineers a flame burns from its outside envelope (the boundary between mixed gas and oxidizer with ambient air) inward from all directions, but because a gas flame proceeds out of an orifice at speed it also has a very strong tendency to burn from its front backwards; thus, I suspect began the term "wave front." Wave front is also a more useful descriptive term for my purposes than envelope, because all my burner designs are deliberately made to speed up mixture feed, and then to ignite it well inside the flame nozzle in order to modify the natural tendency of a gas flame to burn from front to back with a constant source of ignition from back to front; this is how a burner can achieve complete combustion of propane (and all other LP fuel gases) in a single primary "envelope." One of the things that's so handy about this group are the constant reminders that being "right" is only as valuable as the ability to communicate that "right" answer to others; when there is such a thing as one right answer...and when you challenge mine, you sharpen me. Thank you.

Flame envelopes, cones, and wave fronts are different descriptions of coherent flame configurations. I got into the habit of using the term wave front, because I was reading a lot of material written by combustion engineers who were concerned with "designing" better flame configuration, for better combustion in industrial equipment. Torch experts usually speak of flame envelopes (inner and outer). I suppose flame cones would be a description more likely to be found in gas stove and hot water heater maintenance manuals. Regardless, it's all just different lingo for flame patterns. I simply say secondary combustion for what you call an outer flame envelope because my burners are designed to dispense with secondary combustion altogether at best and leave only a wisp of secondary combustion at worst; nothing that could meaningfully be described as a flame envelope, what you call the intermediate cone is my primary wave front, while a white inner flame cone doesn't exist on any decent forge burner. Instead, a clear cone shaped area should only denote the back side of a primary combustion wave (flame "envelope"). You're simply asking the wrong question about flame "types" for different smithing tasks. Unlike torch work, the last thing you want is to aim the flame directly at a work-piece being heated in a forge, where the flame should be used to heat the forge interior, which then heats the part indirectly. Always remember, that a flame is an ongoing chemical process creating heat as a byproduct. Inside that chemical process exists free super-heated molecules of oxygen, which cause scale to rapidly form on heating steel. Burners that produce secondary flames shoot super-heated oxygen molecules quite a long way. You will commonly see burners aimed at forge floors, but only to avoid direct flame impingement of insulated walls, where it would do much more damage than causing scale to form on part surfaces. However, there are ways around this problem. The short hard multiple flames created by a ribbon burner burn further away from the work than longer single flames from other burner types. And if you are willing to install refractory rings over insulated walls to protect them from direct flame impingement, your burner(s) can then be located on the forge bottom, facing upward; this gives a flame three times the travel distance before encountering parts then down facing burners. The correct question is what forge design does one want for blade smithing. Think of the burner as just one more part interacting with the rest of your forge, and you'll do much better. So, what size forge is best for the blade smithing you plan to do? will you make pocket folders or Bowie knives, swords, and axes? After you answer that we can deal reasonably with the question of what kind of burner design you need.

Burners can be run without flame nozzles (AKA flares) inside a forge; possibly because of back pressure; I don't pretend to have thought much about this phenomenon. This doesn't mean you are getting a stabil flame; just that your flame is being helped not to blow out by the forge. One of your photos shows the flame trying to do just that. The increase in internal diameter of your screw on "flare" simply isn't sufficient. A tapered flare uses pipe (stainless steel for better wear characteristics), the next size up from a burner's mixing tube, which is an internal diameter about 1/8" larger than the tube it mounts on; to this is added another 1/8" of increased diameter by hot tapering. My nozzle design uses a spacer ring between the mixing tube and an outer tube; together they constitute a flame nozzle with a different shape, but the same approximate 1/4" increase in internal diameter between mixing tube and nozzle interiors. The point of these "flairs" is to provide a drop in air/fuel mixture pressure just behind the flame, which allows the pressure of ambient air to push against the expanding flame, helping it to stay "glued" to the burner, instead of blowing off its end. This allows a burner to be turned up much higher than it can be otherwise. All you have to do in order to test this point is to saw off that coupling even with the end of the mixing tube, and slide another pipe over it so that it overhangs the end of the cut down coupling by about 1-1/4" light up the burner and slide the pipe back and forth on the coupling to vary the amount of overhang, and watch to see how it effects the flame. When you're satisfied with the results, measure the overhang, and that length to the width of the cut down coupling, and cut the outer pipe to that length. Mount your new flare with a single screw, because mild steel won't last long; but it will get you by until you can purchase that size tube or pipe in stainless steel.

Also, that burner does not look like a stabile design; it has no flame nozzle, and no funnel shape at its rear end.

Just google Gas Burners for Forges, Furnaces, & Kilns PDF

That's one-half of a good idea. You need to build a sheet metal hood with a powered exhaust to put through that window, and the exhaust needs to extend out beyond the wall a couple of feet, turning upward at its end. The CO alarms are good, but you need to cover the forge area with cement board for additional fire protection, as though it were a wood stove; hang a couple of fire extinguishers on the wall too. When finished, you should call the fire department and volunteer to have them inspect your set up and advise you on any recommended improvements. This establishes a nice paper trail to show a judge, in case your ex tries to use your hobby against you.

Kriptonite is wicked stuff, whatever form it comes in

How about Glen? How about Glen?