Mikey98118

Silver Brazing to S.S. Funnels Being able to silver braze funnels to pipe or tube products is a great convenience. Unfortunately (even with sausage stuffing tubes included), working with what is available in the market restricts your possible repurposing selections, because the funnels that can easily be mechanically trapped within (or on) mixing tubes are very limited. Also, some funnels of superior size and/or shape have spouts that are way too small for your purposes, and must have their small ends cut off, and then be silver brazed onto the mixing tube, without benefit of a tubing in tubing joint to fill. Once you have the mixing tube cut to length, measure how long it and the funnel are together; Buy a long enough length of 5/16-18 threaded rod from your hardware store, (or an online source) to extend comfortably beyond both funnel and mixing tube, with room to spare for a nut and large flat washer on the tube end, and another washer or sheet metal plate to cover the funnel’s large opening. This arrangement keeps the parts trapped tightly together, in straight axial alignment. Preparation for this work starts by laying a free-flow burner’s gas assembly’s mounting plate and rivet nut, or drilling and threading a force-flow burner’s aluminum fan mounting plate, because it will be used, after lay-out and before cutting out is completed, to help hold the funnel and mixing tube in correct position for brazing. Using flat washers to trap the funnel and mixing tube together for silver brazing: The mounting plate can be employed, together with a rivet nut to secure the forward end of a mixing tube against a funnel, for silver brazing these two parts on free-flow burners. The funnel on smaller burners can be secured with a second washer and hex nut. Larger burners will use the rivet nut on a mounting plate cut from sheet metal on the funnel bottom, and a flat washer secured with a hex nut over the front of the mixing tube. Using a flat washer and aluminum plate to trap the mixing tube: Forced-flow burners use a flat washer and hex nut on a threaded rod, to trap the mixing tube against the funne. The bottom of the funnel is trapped in place with a ½” thick aluminum mounting plate, which is drilled and threaded with a 5/16-18 tap, so that it can be used, instead of a rivet-nut, to hold the threaded brass gas tube. First lay the aluminum plate out in a square, which is 1” wider and longer than the outside dimensions of the axial fan. Then, scribe lines are from corner to corner, in both directions to establish the plate’s center. A prick punch is used to mark where the lines cross, and a circle is scribed, using dividers; the circle is equal to the funnel opening—never more; although it can be smaller. If you are going to use a hole saw to cut the center hole, go ahead, and cut into the plate ¼” deep at this time, since you while not be able to use the saw’s pilot bit to keep it centered, after drilling out the hole to screw in a 5/16-18 threaded rod. Afterwards the existing trench in the plate will end the need to use the saw’s ¼” pilot bit. At this point the pilot hole is drilled and threaded, to screw a 5/16-18 threaded rod through, so that this part can be temporarily employed as an aid for braze work. If you are going to use a line of holes, the divider is narrowed 3/16”, and a 3/8” smaller inner scribed circle is also made, before drilling and threading a 5/16-18 hole. The mounting plate can be used “as is” on free-flow burners. Forced-flow burner fan ½” thick aluminum mounting plates are first laid out in a square, which is 1” wider and longer than the outside dimensions of the axial fan. Then, scribe lines are scribed corner to corner in both directions to establish the plate’s center. A prick punch is used to mark where the lines cross, and a circle is scribed, using dividers; the circle is equal to the funnel opening—never larger, although it can be smaller. If you are going to use a hole saw to cut the center hole, go ahead, and cut into the plate ¼” deep at this time, since you while not be able to use the saw’s pilot bit to keep it centered, after enlarging the hole to screw a 5/16” threaded rod into. Afterwards the existing trench in the plate will end the need to use the saw’s ¼” pilot bit. At this point the pilot hole is drilled and threaded, to pass a 5/16-18 threaded rod through, so that it can be temporarily employed as an aid for braze work. If you are going to use a line of holes, instead of a hole saw, or jigsaw to get rid of the center of the plate, the divider is narrowed 3/16”, and a 3/8” smaller inner scribed circle is also made, before drilling and threading a 5/16-18 threaded center hole. Note: It is vital that the center hole be drilled perpendicular to the aluminum plate. Otherwise, the funnel will not remain axially true to the mixing tube during silver brazing. A brazing assembly consisting of the 5/16-18 threaded rod is used, along with the aluminum mounting plate, mixing tube, aluminum plate, plus a nut and washer, is used to hold the funnel and mixing tube in line while they are being joined. The funnel and mixing tube are held tightly together and axially true for silver brazing this way. Before placing the mixing tube against the funnel, check both tubing ends to see if one is cut more squarely; that is the one to place against the funnel; this assures a good match up with the funnel, and should be used for the joined end; the other end, which you might have to cut to length, must be double checked with a square, and power sanded to a reasonable proximity to perpendicular with its axis. How close is close enough? Without a lathe you will not even approach perfection; nor do you need to. Double checking your work with a square will bring you more than close enough for your needs, because the flat washer allows a little play in the parts. The mixing tube must be ground to mate up closely to the funnel’s taper; this is very important for easy whetting of the silver braze alloy into the tube/funnel joint. 60 grit wet/dry sandpaper can be attached to the funnel with double sided tape (sticky on both sides), to finish shaping the tube end exactly to it, and the mixing tube is turned back and forth on it. Next, the end of the funnel must be scribed, to mark where it meets the tube’s end; use the dividers to measure the length of the internally beveled area on the tube’s end, and then a mark a second line 1/8” further up the funnel wall than that. Cut the end of the funnel away at the second line. The 1/8” the excess material is ground away after the joint os silver brazed. You want to leave enough excess funnel wall to catch any excess filler alloy, while the filler completely covers the joined area. After brazing, the joint must be cleaned, and the rest of the excess material must be ground or power sanded back even with the inside surface of the mixing tube. It takes a minimum of 53% silver content for filler alloys to be effective when silver-brazing stainless steel parts, and those are difficult to find. However, 56% and higher silver content brazing alloys are easily available on the open market, and will work better on stainless to stainless, or stainless to mild steel joints; they have the lowest temperature flow range (around 1200°F; 649°C), and best wetting characteristics. High silver content filler alloys are the only ones that are going to work well on S.S funnels. Procedure for joining thicker mild or stainless-steel coupling or mixing tube to thin S.S. funnel: Both tube and funnel are cleaned, scoured and fluxed before being secured tightly together with fender washers, etc., on a carriage bolt or length of all-thread, and placed on a level surface. Using a propane or propylene torch with a brush flame, mostly heat the thicker tube with the primary flame at least ¼” away from the parts. Only allow the secondary outer flame envelope to touch the part surfaces. Pass the flame back and forth along the joint. Once the flux indicates the correct temperature has been reached (black flux by bubbling; white flux by bubbling and turning clear), dip the filler onto the joint area, and heat the drop or so of silver braze filler with the torch, while allowing the flame to also heat the funnel a little bit; as you again pass the flame back and forth, the heated joint will suck the filler in, spreading it along the joint. Turn the parts to expose an area beside the one you just finished, and repeat this process, over and over until the entire joint is filled. Note: Make sure to buy threaded rod (AKA all-thread) that matches the size and type of external thread on your gas tube. When you silver braze pipe or round tube onto a funnel, it is important to ensure a very close fit for a good braze job, leaving a gap of no more than 0.005” anywhere that you want the filler metal to flow. Take all the time you need to ensure the best possible fit between tube and funnel, that you can manage. It helps to finish the fit-up by placing sandpaper between the mixing tube and funnel, to finish matching their surfaces closely. Any convex curvature in the funnel wall will increase your work (but is likely to be well worth it). When the tube or pipe is a close fit, note how wide the area of contact has become; this is what caused all that extra work, and is also the reason why this joint will end up strong enough to serve. If your brazed joint ends up with gaps in it, consider closing them in with silver solder. Grind or power sand a bevel in the end of the tube as close as possible to the funnel’s shape, and then scribe or ink an outer line where the two parts meet. Remove everything that hinders your view of the funnel area you are going to remove. Measure the widest section of the tube’s inner bevel, and add another 1/8” of distance to it; then mark points along that distance for an inner cut line. Cut away the funnel up to those points. Place the tube back on the funnel, and ink a line on the funnel where the inside surface of the tube meets it. Grind or power sand right up close to, but not touching, that line; this is to keep your finish sanding or grinding work inside the funnel to a minimum, after the brazing is finished. But, a slightly smaller opening in the funnel than the inside surface of the pipe or tube, provides a ledge to help prevent the filler metal from making a mess; it is well worth a little extra grinding or power sanding afterward, to prevent that. Sand or wire brush the area that you want to braze, to roughen part surfaces (promoting capillary flow), and then flux both parts; but only on the areas where you want the filler to flow. Clamp both parts together, to keep them securely trapped in position during brazing. You will have to use a silver braze alloy with at least 56% silver content, and flux meant for use on stainless-steel. 65% silver filler is even better, because the higher the percent of silver in your filler alloy the better it wets part surfaces. Wetting is the necessary first step to the filler flowing over part surfaces and into the joint. Note: Both soldering and brazing use capillary action to move filler metal over part surfaces in the joint area; For the process to begin, filler metal must start combining with the metal on the surface layer of the part; this is called wetting. Without wetting, the filler metal will just ball up on the part surfaces, and drop off. Silver content in the filler alloy promotes wetting. Stainless-steel’s chromium content is why it requires a filler rod or wire with a high percentage of silver to promote wetting. Chromium is hard to wet, which is why 18:8 is easier to silver braze than 18:10 stainless. Procedure for joining a thicker mild or stainless-steel mixing tube to a thinner S.S. funnel: Both tube and funnel are cleaned, scoured, and fluxed before being secured tightly together with fender washers, etc., on a carriage bolt or length of all-thread, and placed on a level surface. When you silver braze pipe or round tube onto a funnel, it is important to ensure a very close fit for a good braze job, leaving a gap of no more than 0.005” anywhere you want the filler metal to flow. Take all the time you need to ensure the best possible fit between tube and funnel, that you can manage. It helps to finish the fit-up by placing sandpaper between the mixing tube and funnel, to finish matching their surfaces closely. Any convex curvature in the funnel wall will increase your work (but is likely to be well worth the added effort). When the tube or pipe is a close fit, note how wide the area of contact has become; this is what caused all that extra work, and is also the reason why this joint will end up strong enough to serve. If your braze job ends up with gaps in it, consider closing them up with silver solder; this flows at much lower temperatures, so the braze job is in no danger of being ruined. Grind or power sand a bevel in the end of the tube as close as possible to the funnel’s shape, and then scribe or ink an outer line where the two parts meet. Remove everything that hinders your view of the funnel area you are going to remove. Measure the widest section of the tube’s inner bevel, and add 1/8” more distance to it; then mark points along that distance for an inner cut line. Cut away the funnel up to those points; this is to keep your finish sanding or grinding work inside the funnel to a minimum, after the brazing is done. But, a slightly smaller opening in the funnel than the inside surface of the pipe or tube, provides a lip to help prevent the filler metal from making a mess; it is well worth a little extra grinding or power sanding after brazing, to prevent that. Mount a wire brush in your rotary tool, to remove oxides and roughen the surface of the area that you want to braze, and then flux both parts; but only on the area where you want the filler to flow. Clamp all of the parts together, to keep them securely trapped in position during brazing. You will have to use a silver braze alloy with at least 56% silver content, and flux meant for use on stainless-steel. 65% silver filler is even better at whetting part surfaces. When using an air-fuel flame, mostly heat the thicker tube with the primary flame at least ¼” away from the parts. Only allow the secondary outer flame envelope to touch the part surfaces. Oxy-fuel flames should not touch the part surfaces at all. With high-speed air-fuel burners, which can be tuned to a single flame envelope; keep the end of the flame tip ¼” away from part surfaces. Pass the flame back and forth along the joint. Once the flux indicates the correct temperature has been reached (black flux by bubbling; white flux by bubbling and then turning clear), touch the filler on the joint area, and heat a drop or so of silver braze filler with the torch, while allowing the flame to also heat the funnel a little bit; as you again pass the flame back and forth over it, the heated joint area will suck most of the filler in, spreading it along the joint. Turn the parts to expose an area beside the one you just finished, and repeat this process, over and over until the entire joint is filled.

The simple answer is NO! I have been to their site, and can say in their defense that their product looks to have been improved. But, Diamondback forges have also been improved; I suggest you look there for your forge, to get your money's worth. As to the idea that 'mass production' is doing anything to keep commercial forge prices down; the answer to that is a big fat NO too. Prices are based on what the market will bear--period. Yes, you can save money by building your own gas forge; however, how much is saved is directly dependent on how much reading and thinking you do before starting work. Bottom line is that building to save money isn't a smart plan for most folks. Building your forge will do a fine job of increasing knowledge of one of your shop tools, and if you are careful, your forge will be better than anything you can buy; that is the only way to "get your money's worth" by building a gas forge. You also need to do some reading, to get your money's worth when buying. After designing and building this equipment for a quarter century, that is my well considered opinion.

I havent had knife greed since I was a kid; untill I sow yours

Adjustable pressure regulators The first piece of equipment attached to a refillable fuel cylinder, should be a variable pressure regulator. You cannot use an old acetylene regulator for any other fuel gas; they are illegal, and unsafe to use with LPG fuels. While you can use an industrial multi-fuel gas regulator from a torch set, LPG regulators are less expensive and better suited for use with these fuels in cold weather. I recommend using a 0 to 30 PSI model, with a pressure gauge attached, although a 0-20 PSI regulator will work okay, for most people, most of the time. You can find good quality 0-30 PSI propane regulators offered on Amazon.com, or other online sources; or find them locally at most large hardware stores. If you end up with a regulator that does not have a pressure gauge, or a side port on which to install one, you can add a “T” pipe fitting at the regulator’s outlet and install a pressure gauge there, using s short pipe nipple in its end opening, a regulator outlet bushing in the other end, and the gauge screwed into middle opening. A pressure gauge should be a helpful training aid, for the novice; once familiar with their equipment, most people ignore them.

The exit hole on a Frosty "T" burner's gas orifice, faces straight toward the opening of the burner's mixing tube. Maximum air induction is obtained by filing the gas tube's MIG contact tip shorter; creating more distance between gas orifice and the opening. The exit hole on a Mikey burner's gas orifice, faces straight toward the opening of the burner's mixing tube. But, maximum air induction is obtained by sliding the gas tube's MIG contact tip closer; creating less distance between gas orifice and the opening. Why would apparently opposite moves create the same outcome? Because the incoming air stream flows past the gas orifice from behind in a Mikey burner. Two incoming air streams are induced into the burner from right angles to the gas orifice in a "T" burner. So, the method is different, but the reason why, and the outcome is the same in both kinds of burner. The reason why being maximum air induction.

So, if all we need is more interior room to complete combustion in, and if we would rather have bigger forges anyway, its a freebee, right? WRONG! I'm telling you what you can get by with; not what is the best move. "There ain't no free lunch." The larger the forge interior the greater the area of heat loss by conduction, which requires more fuel to keep internal surface temperature sufficiently high, which bites you right in the fuel bill. Latitude is a good thing, when you're just getting started. Efficiency is the right move in the long run.

So, it would be reasonable to ask just how good a burner qualifies for these figures? We are not discussing some perfect burner, with a compact neutral flame (even though I'm a notorious picky-butt). All the burner needed to reach these goals, is what was considered a good burner a quarter-century ago. If the burner can put out a good enough flame to not have any tinge of green in it, and not produce an exit flame from the equipment exhaust opening, it will be good enough to succeed, so long as the the equipment is properly made. Even a 40/60 flame will do the job; that is forty percent primary flame to sixty percent secondary flame. The point of striving for a superior flame from your burner, is to reduce the area needed for complete combustion to occur within the heating equipment. But there is a lot of latitude between a perfect flame and an acceptable one

Mixing tube sizes The first thing you must decide about your burner is what size it will be. Home-built burner sizes are based on schedule #40 pipe sizes (or its equivalent inside diameters in round tubing) which are used as the burner’s mixing tube. These burners were built from fractional water pipe for many years (and many still are). So, it is handy to know what actual inside diameters these nominal pipe sizes have, since it is the inside diameter, you are trying to match with the right gas orifice diameter. Actual Imperial (fractional) pipe diameters are larger than their nominal pipe sizes, both outside and inside. If you choose tubing instead, it will seldom be an exact match with schedule #40 pipe sizes, so choose a little larger inside diameter, when possible (rather than a little smaller), for your burner’s mixing tube. Imported stainless-steel tube can be a handy alternative to fractional tube in the smaller sizes, and is more likely to match up well with most stainless-steel funnel shapes. Imported cast stainless steel pipe, while being advertised in inches on Amazon.com, are nearly all made to metric dimensions; not fractional, no matter what their online advertisements claim. Pipe dimensions: (A) 1/8” schedule #40 pipe is 0.405” O.D. x 0.270” I.D. 10x8mm tube (0.390” O.D. x 0.312” I.D.). The burner’s flame retention nozzle size is 0.493” I.D; this is sufficient to heat 22 cubic inches on naturally aspirated burners. Turn-down range for this burner size i 1,875 to 18,750 BTU per hour, when burning propane, and 2,494 to 24,937 BTU per hour when burning propylene. It would take two of these burners to heat even a two-brick forge on propane. (B) 1/4” schedule #40 pipe is 0.540” O.D. x 0.364” I.D. 12x10mm tube (0.468” O.D. x 0.390” I.D.) tube. The 1/4” burner’s nozzle is 0.622” I.D.; this is sufficient to heat 44 cubic inches on naturally aspirated burners. Turn-down range for this burner size is 2,500 to 25,000 BTU per hour, when burning propane, and 3,750 to 37,500 BTU per hour, when burning propylene. Two of these burners will easily heat a coffee-can or one gallon paint can forge to welding temperatures. A single burner this size must be perfectly made, in a properly designed forge to reach welding temperatures. (C) 3/8” schedule #40 pipe is 0.675” O.D. x 0.493” I.D. 14x12mm tube (0.546” O.D. x 0.468” I.D. tube. The 3/8” burner’s nozzle is 0.824” I.D.; this is sufficient to heat 88 cubic inches on naturally aspirated burners. Turn-down range for this burner size is 5,000 to 50,00 BTU per hour, when burning propane, and 7,500 to 75,000 BTU per hour, when burning propylene. Two of these burners will easily heat a non-refillable two gallon refrigerant or helium cylinder forge to welding temperatures. A single burner this size must be perfectly made, in a properly designed forge to reach welding temperatures. (D) 1/2” schedule #40 pipe is 0.840” O.D. x 0.622” I.D. 18x16mm tube 0.702” O.D. x 0.624”) I.D.) tube. The 1/2” burner’s nozzle is 1.049” I.D.; this is sufficient to heat 175 cubic inches on naturally aspirated burners. Nearly 5/8” actual inside diameter. Turn-down range for this burner size is 10,000 to 100,000 BTU per hour, when burning propane, and 15,000 to 150,00 BTU per hour, when burning propylene. Two of these burners will easily heat a five-gallon paint can, or used propane cylinder, forge to welding temperatures. A single burner this size must be perfectly made, in a properly designed forge to reach welding temperatures. (E) 3/4” schedule #40 pipe is 1.050” O.D. x 0.824” I.D. (imported cast stainless pipe is 1.026” O.D. x 0.831” I.D.). 20mm pipe nipples and couplers are 0.78” The 3/4” burner’s nozzle is 1.315” I.D.; this is sufficient to heat 350 cubic inches on naturally aspirated burners. 0.075” larger than ¾” diameter. Turn-down range for this burner size is 20,000 to 200,00 BTU per hour, when burning propane, and 30,000 to 300,000 BTU per hour, when burning propylene. Two of these burners will easily heat a five-gallon paint can, or used propane cylinder, forge to welding temperatures. A single burner this size must be perfectly made, in a properly designed forge to reach welding temperatures. (F) 1” schedule #40 pipe is 1.315” O.D. x 1.049” I.D. 1” schedule #10 pipe’s outside diameter is 1.315” by 1.109” inside diameter; this is sufficient to heat 700 cubic inches on naturally aspirated burners. Single or multiple one-inch burners are used in commercial forges, and pottery kilns. Note: “Sufficient to heat” means that it can raise a properly built forge interior of those cubic inches to welding heat, or bronze, in a properly built casting furnace, to pouring temperatures. Are these figures legitimate? In fact, they are under stated; not over reaching.

Volcano Forges are just a memory, so why do I bring this forge idea up at all? Because some ideas take years to become popular; but, if they are good ones, there is no stopping them. Oval forges took more than a quarter century, but now they are all over the place. You know how fond I am of complicated construction choices. Nevertheless, I recognize that "simple as a mouse trap" whens out over time

Volcano Forges were an excellent example of how well doghouse forges work out. I few further thoughts on the matter: You can mark the forge’s outline on cardboard, or some other flat surface, and then draw lines parallel to the forge bottom at the same height that the materials of the forge floor will make. Next, move a square and ruler, up and down the roof line, to determine where to cut holes for the burners. You want the flames to impinge at the far end of the floor, but short of the far wall, for maximum swirl in the forge atmosphere, while missing the parts being heated.

It is a description of the forge shape, which I picked up yesterday, from an old (2014) IFI post, which I stumbled across out there on the Net. I thought it was apt enough to bear repeating, so I did

Doghouse forges Pentagon shapes can be easily bent, welded, or silver brazed in position from sheet metal, but their advantages do not end there. When one or more burners are mounted in one side of its roof, they can be aimed at a convenient angle into the forge interior, while remaining perpendicular to the sheet; thus, allowing steel conduit connectors, or pipe fittings to be employed to trap burners in place. Volcano Forges were an excellent example of how well this design works out. This forge’s pentagon shell is easily filled with ceramic wool, and then rigidized into an interior shape like that found in “D” forges. But, unlike “D” forges, Doghouse forges can be lined with ceramic board, under a heat reflecting finish coat. Baffle walls made of firebrick against the rear opening, and about 1” away from the front opening complete these forges, without need of sheet metal on either end of the forge.

To complete the thought; cheap also means cheap to replace, if it doesn't turn out durable enough, to defend itself from students

I just hate it when the "circumstances alters cases" rule forces me to totally go against all my favorite advice First overturned advice is "do not choose a Majestic forge." I hate their design, as it creates lots of opportunities for trouble. However, it also allows the most choices for what can be heated in any given gas forge. This being a school forge... Second favorite advice is "do not use a half break for a forge floor." However, that is exactly what I would use in a school forge, as it is cheap and fairly durable. Finally, I generally do not think that ceramic board insulation is worth the investment, and feel ceramic wool is a better use of funds, in a first forge. However, with students, the more rugged board would make a wiser choice.

Just the changes that I noticed back then, Frosty: (1) All welding has been replaced with nuts and bolts construction, which is more appropriate for fast production rates, and convenient shipping; a big plus factor. (2) The ceramic board insulation it once came with has been replaced with ceramic wool; this downgrade is a minus factor, which is more than offset by the price reduction in the single burner forge, allowing more newbies to afford a reliable entree level forge. Then, ceramic board can replace the cheaper wool, when it is time to reline the forge. However, their two burner forge is ridiculously overpriced. As you know, it is only their single burner forge that I ever felt to be worth the money. (3) No more inflammatory personal comments; the silence is golden; this change is the one that makes me suspect the company is finally under new management

Actually, I'm a lot more curious about the changes in Diamondback forges, which is the only well know forge that has dared to improve anything in the last quarter century, while I've been watching. I have to wonder if the original guy is still around... None of it sees to fit his style

Did this problem ever get resolved?

I suggested kiln shelves for forge floors for years. However, the prices of high alumina kiln shelves have become ridiculous... Circumstances alters cases, one more time.

Not really. All you want to look at is how heavy the product rating is; 8 lbs is good. Then look at what its use temperature rating is; I assume that it is 2300F, which is standard, and good enough.

I think there are people on this group who own these forges; since my introduction to them was reading people who were trying to revive old Majestic forges, with quite negative results, I must confess to being prejudiced against them. Nevertheless, I can think of one person on this group who likes his. He is the guy you need to talk to on this subject.

We all tend to look for ways to be "first-est with the most-est." The thinner the hard cast refractory flame layer outside of a ceramic wool insulating layer the faster a forge will heat up. And we assume that the only downside is that thinner hard refractory layers are fragile. But, that is only part of the picture. For, the flame face layer has has two sides; its flame side and its far side. If the flame side reaches 2300 F, the far side will likely reach 2000 F--in a one inch thick layer of Kast-O-Lite 30. With non-insulating refractory, or with a thnner layer, the heat of the far side will only increase. So, what? So, the closer your ceramic wool insulation comes to its use-rating the faster it will last. Lattiscino is also right about high alumina kiln shelves having become too expensive to make a smart choice as forge floors, these days; I just hate this fact...but facts are facts

Is that why he doesn't post here anymore? Gone fishing?

I have worried over this for some years, and decided that the addition of small springs at one end of the threaded rods, trapped between the angle irons and a flat washer would make a valuable addition to this forge design. One aspect of this idea that is pleasant,is that,, so long as additional length for the springs is included in the threaded rod, they can be added at any time.

Ron Reil's forge pages is where I started twenty-five years ago. His burners are quite out of date, but you can find a very nice little forge on his site; it's construction is a little dated too, but it will work. https://ronreil.com/design1.shtml Gas Burners for Forges, Furnaces, & Kilns is also dated, but since it was pirated, you can find its information for free on the Net. There is a chapter about building a forge from a five-gallon propane cylinder, which should give you all you need to know; just raise is floor, to create a "D" forge. You should also disregard its door, and use a movable brick wall near the forge opening instead. The are photos of brick pile forges here, and on other websites; they are quite simple to build.

The problem is that you are asking a perfectionist that question. For all practical purposes, the answer is NO. Ugh! That sprained my brain. The bottom lie is that burners will run in most forges, without a flame retention nozzle. However, that does not mean it is a good idear to do so. The any flame retention nozzle is considered to be a consumable, because the burner's nozzle will be heated up to yellow hot in that environment. So, a propane flame will slowly oxidize it away. If there is no nozzle to take the abuse, then the mixing tube will start being oxidized away instead. Do you see the point of using a pipe coupling, now? Lots of people use a stainless steel pipe reducer as a make shift flame retention nozzle. What, as a certified picky-butt, can I say about this deplorable decision? Only that they are cheap, easy, and they work. Double ugh! After that, I need aspirin. My fingers are betraying me all over the place