Mikey98118

AFB, your naturally aspirated vortex burners are stronger running than any naturally aspirated design of mine. Nevertheless, they don't come up to the point where two different flame retention nozzle diameters are needed--yet. It would be fascinating to find out what the inclusion of angled fins at the air entrance might add to your design... "Just when you thought it was safe to go back into the water."

You might just be falling a little behind, Frosty I still size burners by schedule #40 pipe internal diameters. That came from the narrowest point in wasp-waste burners; this has not changed. What has changed, just a little bit, is that fan-induced vortex burners can run two different flame retention nozzle diameters; no other burners, including naturally aspirated vortex burners, can use more than one flame nozzle diameter. So, for fan-induced vortex burners ONLY, it is true that flame nozzle diameters are the limit of burner output, rather than mixing tube inside diameters; its a very limited exception to a rule that normally applies. It is still another case of circumstances altering cases This only applies to fan-induced vortex burners; these must use more than one flame retention nozzle diameter. No other burner needs more than one flame retention nozzle diameter; not even naturally aspirated vortex burners. So, these particular burners prove the only exception to the rule--at present

About burner sizes (1) A 1/8” burner’s nozzle size is 0.493” I.D; this is sufficient to heat 22 cubic inches on naturally aspirated burners. (2) A 1/4” burner’s nozzle is 0.622” I.D.; this is sufficient to heat 44 cubic inches on naturally aspirated burners. (3) A 3/8” burner’s nozzle is 0.824” I.D.; this is sufficient to heat 88 cubic inches (4) A 1/2” burner’s nozzle is 1.049” I.D.; this is sufficient to heat 175 cubic inches on naturally aspirated burners. (5) A 3/4” burner’s nozzle is 1.315” I.D.; this is sufficient to heat 350 cubic inches on naturally aspirated burners. (6) A 1” burner’s nozzle is 1.61” I.D.; this is sufficient to heat 700 cubic inches on naturally aspirated burners. Note: “Sufficient to heat” means that it can raise a properly built forge interior of those cubic inches to welding heat, or melt cast iron in an equal size casting furnace. Are these figures legitimate? In fact, they are under stated; not over reaching. What about the optional second (larger) flame retention nozzles on fan-induced burners? Whatever inside diameter is used with one of them, with the gas pressure turned up to match the fan running at full speed, can be considered as producing a flame equal to that nozzle size in a naturally aspirated burner. You can more than match the maximum output on the next larger size naturally aspirated burner. The number of cubic inches that can be brought to welding temperature in a properly built forge, or the number of cubic inches in a casting furnace that can be brought to iron casting temperatures (from a burner with a neutral flame), depends on the inside diameter of its flame retention nozzle; this is limited by the diameter of a burner’s mixing tube, in naturally aspirated burners, but nozzle diameters on fan-induced vortex burners must be larger, when the fan is running at full power, and the fuel gas is increased to match its increased air induction, so the amount of cubic inches a fan-induced vortex burner will sufficiently heat depends on the internal diameter of its flame retention nozzle; not on its mixing tube diameter.

Five-gallon forges Five-gallon propane cylinders were used for most of the early home-made gas forges and casting furnaces; they are still the most popular container size for “tube” and “D” shaped forges; these forges are at their most efficient, when run from two 1/2” size burners, placed low on the wall a little higher than the forge floor; aimed up and inward, so that the flame has the longest possible path to combust all oxygen in incoming air, before it can impinge on heating parts. With the burners placed at one-third and two-thirds of the distance to the rear of the forge, the far burner can be shut down, and a movable refractory baffle, placed midway between the burners, portioning off one-half of the forge, to save fuel, when heating small parts. This strategy works best on forges with a hinged and latched end door. 20-quart stainless steel canning pots are available on eBay for $26; this is equal to a five-gallon propane cylinder in area, and is a slightly more convenient shape. Five-gallon steel paint cans have also been employed. Five-gallons is the favorite size container for casting furnaces, and the main difference between a tube forge and a casting furnace is that the forge is positioned horizontally, and the furnace is vertical. With a little added work on its legs, and the addition of a rear hole to let liquid metal escape into a metal sand box (in case of crucible failure), a forge, with a hinged and latched door, can be made to do both tasks.

The Two-gallon mini-forge Mini-forges have been built for years from empty non-refillable helium tanks (sold for inflating party balloons), or empty non-refillable refrigerant gas cylinders used by HVAC companies; so far as I know, Ron Reil first posted one of them to the Net. By law, empty nonrefillable cylinders must be properly disposed of (which costs money), so they are not hard to talk businesses out of, once you explain what you want to do with them. This size forge can be run from one ½” burner, or two 3/8” burners. A more recent knife-maker’s variant on two-gallon tubular forges, are mini-oval forges; these were first made from truck mufflers that were cut in half. But stainless steel oval trash cans can be made to serve with a lot less effort, with superior results; they should be run from two 3/8” or three ¼” burners, placed high on one side, and aimed slightly up and toward the forge’s far side. 2.09-gallon stainless-steel oval trash can; 10.9” wide, by 9” long, by 6.4” high. Use three ¼” or two 3/8” burners; ($23.49 through Amazon.com).

Note: Dual-fuel torch-heads (emplyed with propane and propylene gases) usually have thin-walled stainless steel flame retention nozzles, which can be slid into thicker walled stainless steel tube, to protect them from high heat oxidation losses.

The two-brick forge Box shaped forges are the logical choice, when you use insulating firebricks, or ceramic board insulation in a forge. If you employ hard ceramic board as the flame face material, with ceramic fiber blanket for secondary insulation, then a sheet metal shell is needed. If you choose insulating firebricks, nothing more than four threaded rods and four pieces of steel angle stock are needed, to hold the larger “brick pile” forges together, or furnace cement, Plistix 900, etc. to glue the bricks together for a mini-forge. The two-brick forge is merely chiseled out of soft insulating firebricks; since the bricks are wider than they are tall, carving out two halves of a cylindrical shape is ill conceived; it is just as easy to carve two halves of an oval into the bricks; creating a larger chamber to work in. It is also best to leave one end of the hollowed-out area closed. Drill the hole for your burner two-thirds of the way toward the forge’s closed end, and slanting upward a little bit, to encourage the hot gases to swirl its way toward the forge’s open end. Seal the brick’s internal surfaces with Plistix 900, so that they will last well, and the forge will get hotter. Note: The burner hole should be about 1/16” larger diameter than the burner’s flame retention nozzle, to keep its expansion from cracking the brick, during heating cycles, and to provide a little secondary air, which most burners need for complete combustion in the forge.

Why and why not to choose a coffee-can forge There seems to be some confused ideas about coffee-can forges being a super cheap way to get into blacksmithing. What they actually are is an economical way to forge small parts, after the forge is built; their real economy comes in minor fuel use. They are also highly portable and compact tools, for those with limited space. The only savings encountered in their construction will be in the economies of scale. You can find ceramic wool blanket offered in squares that are large enough to work in a C-C forge, so you spend less money for it. But you end up paying a lot more per square foot. Castable refractory can be purchased in five-pound bags, but at double its usual price; these are the smart choices. Mixtures of Perlite and water glass (sodium silicate) are going to melt in short order, if you heat the forge up full blast. Perlite and furnace cement are going to break down more slowly, but they still cannot hold up to flame impingement. You would need Perlite and castable refractory to do the job, and then you have just spent enough almost enough money to buy that square of ceramic wool blanket and a five lb. bag of castable refractory. The infamous plaster and sand 'refractory formula' is such a major heat sink that you will end up throwing your forge in the garbage before this so-called refractory has a chance to crack apart! The second cheap and easy idea about C-C forges is that you can simply run them with propane canister-mount torches. There are only a few higher priced propane torches that have stainless steel flame nozzles, and those nozzles are so thin that they quickly oxidize away inside of a forge. Most of these torches have brass nozzles that will melt inside a forge. So, the torch cannot be placed in a sealed burner port. Instead, it can only be placed in an oversized hole, if it is weak enough, or aimed toward the hole from outside of it, if it is one of the hotter models. Either way you go, the torch is destroyed, or the forge is under powered; the answer for this is to replace propane with propylene fuel, at twic the price! So, you need a real burner. But, if you're going to the trouble to build a burner, you want it placed in a forge that is worth it, right? Now you have another problem, because a 3/8" burner is the largest size you can use in a C-C forge, but by the time you have constructed it, you will not want to waste it in a cheaply built "temperary" forge. There are plenty of burners you can build in the 1/2" size, if you are willing to put them in a typical mini-forge (built from a two-gallon non-reusable Freon or helium cylinder). Coffee-can forges have their place, but trying to use them as a cheap and easy way to heat some steel isn’t very bright; that's what charcoal if for. 3 lb. coffee-cans (used for years in coffee-can forges and casting furnaces) are about equal in size to 1 gallon paint cans, or #10 tin cans, or four-quart kitchen pans.

At present, both propane and butane are readily available in Asian metropolitan areas. But while butane was available in the past, LPG (a combination of propane and butane, with traces of methane) is what is readily available in Europe now. In the U.S.A., propane is readily available, but butane is not. Except in 16 oz. cartridges

Gas Assemblies for linear Burners It has been well established that the gas pipe and whatever MIG contact tip, 3D printer nozzle, or other gas orifice is used, should be centered with, and aimed parallel to a burner’s reducer funnel; and that this part must be centered on, and parallel to the mixing tube’s axis, by whatever means is convenient. BUT the devil is in the details, because how you choose to mount the gas assembly, is your first and best chance, to create an intense burner flame; don't waste it! Why such emphases on a “minor” detail? Your burner has an energy budget; it's limited to the air induction that the gas jet creates; this is a naturally aspirated burner's air engine. It takes energy to get incoming air moving, and to change that air’s direction, to create spin. So, starting that directional change at the same point where forward motion begins, will require the least energy from your gas jet’s tiny budget. So why not install a high-power fan or air compressor fitting at the opening? How much breath is required to blow out a candle? That is about the same amount of excess force—input at the wrong place—needed to blow out a burner flame too. If you want an intense flame, it comes from control and balance—not from thoughtlessly pushing incoming air. There is another important factor to consider; as with a whirlpool in your bathtub drain, nearly all air motion is going to happen near to the opening’s periphery. No significant air will move down the center of the entrance. So what? So, this tells you just where streamlining matters—and where it does not. Mounting a gas assembly has two facets; what is easy and what works best. There will be no "perfect” method of balancing these aspects, because, aside from tooling and skill levels, we all have preferences; mine is for maximum control of the parts being assembled; having found that we get the best results for the least work, if Murphy’s law is never given a chance to muck anything up. Gas assemblies are best mounted on naturally aspirated linear burners, by suspending them in the center holes of fender washers, of up to 2-1/2” diameter, keeping your work at a minimum, by doing only part of the work needed to fashion a mounting plate from scratch. For larger openings than 2-1/2” you must completely fabricate your gas assembly’s mounting plate from sheet metal. So, why start with sheet metal, or a fender washer to make a mounting plate? Why not braze together separate parts instead? When you begin with a flat surface; all you need do, is avoid bending it, to assure that the gas assembly mounted to it, will remain perpendicular to the air opening, and therefore axially true to the burner’s mixing tube. Fender washers come in various thicknesses, over which you have little control; because they all have 2-1/2” or smaller diameters, that is okay. But the larger mounting plates that you make from sheet metal need a minimum thickness, to ensure that they stay flat while being worked. 0.079” thickness in stainless-steel plate is strong enough to stay flat when being silver brazed to a funnel, but not so thick that it is too difficult to cut, grind, drill, and thread the center hole, and three air openings. Use a divider (best) or compass (workable), and a prick punch, to lay out a disc of the same diameter as the outside of the funnel’s flange. whether you want to silver braze, solder, screw, or glue it in position over the opening. Drill a hole in the middle of the disc for your threaded gas tube to screw through. Mark out three equal spaces for ribs between the air openings, using the divider or compass (or just estimate using the flats of a hex nut). Drill small holes between the areas of the ribs and outside the area of the gas tube’s two nuts. Remember that there is no significant air flow in this central part of the opening, so don't shortchange yourself on material in this area. The ribs would be too narrow if you kept their lines parallel; that isn't desirable. You want the three ribs narrower at their outer ends, and becoming wider toward the center of your disc, to balance maximum air flow with sufficient material strength. A small brass gas tube needs to have thread, run down its exterior, allowing this gas pipe to move back and forth within a nut, which should be silver brazed on the bottom side of a fender washer, or hand cut mounting plate; this allows the gas orifice on its end to be positioned at the perfect distance from the opening of the mixing tube on a funnel. A second nut is screwed down to the upper side of the mounting plate, to keep the gas assembly rigidly held against it, with the gas orifice at the right distance from the burner’s mixing tube. If the mounting plate is screwed onto the burner funnel’s flange plate (practical with sausage stuffing tubes), then the bottom nut need not be silver brazed in place.

6mm x 4mm (millimeter) brass tubing can be used as gas tubes for 3D printer nozzles on small burners, if tube exteriors are threaded with an M8x1.25 die; still leaving enough wall thickness for internal thread. Better yet, simply stop the external thread short of the tube end with the internal thread. Use an M6x1 tap, to create thread for the printer nozzle about ¼” deep in the gas tube. Silver-braze, silver-solder, or glue the other end of the gas tube into a hose barb. The exterior thread allows you to Silver braze an M8x1.25 rivet nut to a mounting plate, in place of a standard hex nut. These rivet nuts are 3/4” long, with an exterior lip on one end; their thread ends 5/16” short of the end of the nut with an external lip; this makes it nearly impossible to accidentally braze filler alloy on its internal thread. The rivet nut’s full length can be used to ensure proper axial alignment of the gas pipe and orifice, once a flange nut is threaded onto the gas tube. Rivet nuts are also easily press fit into 1/4” aluminum plate, that can be used to make large mounting plates. Use your digital calibers to ascertain the exact outside diameter of the rivet nut, before ordering a drill bit. It is important not to drill an oversized hole. Note: You will use two different kinds of nut. The flange nut has a hex head that can be gripped with a small crescent wrench. The vice grip pliers can hold the tube, while you start running a die down its length. The rivet nut has no head, but can be gripped by pliers; these tools allow you two jamb these two different kinds of nut together on the exterior thread you are creating, once you have threaded a sufficient length of the tube, so that you can more easily finish threading its exterior.

I must respectfully disagree, Frosty. A good shop drawing is likely to convey more information than this computer simulation, but most people will receive more information from this kind of illustration. Magazines like Popular Mechanics, and Mechanics Illustrated seems to have come to the same conclusion long ago

None of these: To begin with, you want at least the thickness of the mixing tube to form a step, even on a tapered nozzle. Secondly, you don't want anywhere near as wide an angle in the taper. Consider what has been said already about successful tapered nozzles for more than twenty years.

All of these burner designs create turbulent--not laminar--flames. The only question is how turbulent. Many of us are interested in how neat and tidy we can make those flames; especially for hand torch work, and for mounting in miniature heating equipment; this can turn out to be a significant amount, but it does not happen by chance. There is plenty of experiential knowledge to be collected about flame retention nozzle design, because what any given nozzle does changes according to mixture flow speed and pressure, so a nozzle that works well on some burners may prove to be a dud on others

Note that tapered nozzles proved ineffective when I started building high speed tube burners; that is why I went to stepped nozzles. The flame retention nozzle needs to match up reasonably well with the burners mixture flow speed.

Treat this area just like you would a regular stepped flame retention nozzle for length, diameter, and shape. Any additional length beyond the equal of the inside diameter, which should be about two pipe sizes larger than the mixing tube, plus an additional 1/8" in length, should increase at about a 30 degree taper, to keep it from affecting the flame.

No: Firstly, no to the idea that casting a replacement for a flame retention nozzle will be the easy path; it certainly will not, and the smaller the nozzle being replaced the trickier that will be to do right. Next; no to the idea that tuning a high speed tube burner in the forge, by how far forward the mixing tube is placed in a built-in refractory nozzle will be easier than tuning than such a burner, with a slide-over stepped nozzle out out in the open air. I'm not trying to hamper you in moving to such a system, for it does have many pluses; but easier tuning of a high speed burner, just isn't among them I don't think that imprvement of this burner will be found at this end; look into change the gas orifice, if you want more heat. As I said, there are real pluses; here is one Another is avoiding the cost of stainless steel tubing (a specially with larger burners), which is becoming serious, in a part that must be replaced every few months.

So, how did your "weekend" project turn out?

And that's when its time to start all over again. There is no finessing our way out of a mess.

Vortex Burner design principles Let us start by clarifying what is meant by the term “vortex burner.” Burners that swirl the flames they make are often touted as vortex burners. But causing a flame to swirl happens far too late in the air/fuel mixing process to provide much benefit; used this way, the description is mere hype. Vortex is a fluid dynamics term, describing a region where the flow of gas or liquid revolves around an axis line. The vortices generated on the trailing edge of plane wings only create drag. At the other extreme, a tornado’s funnel is powerful, but only generates havoc. The gentle current of a bathtub drain effectively employs vortex flow to good purpose, and so should your burner. Vortex burners are simply advanced linear designs; linear burners are chosen over jet-ejector types, to supply maximal vortex motion in their air flow. Good combustion requires incoming air to mix thoroughly with a burner’s fuel gs jet. A swirling motion provides the most mixing for the least drag on your burner’s air flow. When incoming air passes through a constricting tubular shape (ex. pipe reducer or kitchen funnel), vortex movement is generated, becoming an excellent air/fuel mixing aid. Most successful burners, whether linear or jet-ejector, create at least some vortex flow. High-speed tube burners are an exception; they gain swirl from three (fore and aft beveled) rectangular side air entrances; nevertheless, if you place a pipe reducer between their air entrances, and a smaller diameter mixing tube, their performance will be enhanced. Since most successful burner designs create vortex flow, why bring it up? Because the people who designed those burners, only pictured them as swirling incoming air into a stream of fuel gas, and thought no further. Both passive and fan-induced “V” burners, are designed to enhance vortex flow, and then to derive maximum benefit from it. Any device that provides lateral air movement at a funnel opening, will increase vortex flow through the funnel; this includes the two opposed air openings on “T” plumbing fixtures, disc shaped choke plates near funnel entrances, or (my favorite) impeller blades at a funnel’s entrance. If you strip the blades from a cheap or worn-out axial computer fan, and mount them on a linear gas pipe at a burner’s air opening, they will significantly increase vortex movement through the funnel, even though they are still, because they start lateral air movement (spin) at the funnel’s entrance, instead of within it. Installing axial computer fans on linear burners will supercharge vortex flow, but this requires a more complex gas assembly, and an electrical power source. So, it is easier for novices to move from passive to powered “V” burners in stages. Some part shapes used for air entrances on naturally aspirated linear burners, also work well with moving fan blades, while others do not. However, the limits on shape and size imposed by use of moving impeller blades, do not apply to motionless blades; these can be mounted on gas pipes without worry. Straight or curved wall pipe reducers, kitchen funnels, and other constricting tubular shapes provide convenient ready-made entrances for incoming air to spiral its way through, and into the burner’s mixing tube; its ever-constricting path increases its rotational speed, along with its forward velocity (by about one-half of its rotational speed). Also, the faster the incoming air’s rotation, the lower the pressure of the incoming air flow through the mixing tube; this is all very good, but requires the mixing tube to be lengthened enough to stabilize the flame (by allowing friction within the tube to slow the mixture’s swirl and forward velocity, before it exits into the flame retention nozzle). Or, internal vanes near the tube’s exit can be made to slow air spin, in order to keep the mixing tube’s length shorter. A larger diameter flame retention nozzle can break the flow’s exit speed sufficiently. Thus, you would want to exchange your smaller diameter flame retention nozzle, used at lower gas pressures and fan speeds, for a larger one, when running a fan-induced burner full-out. The first thing to keep in mind about funnels and other constrictive shapes, is the greater the ratio between the air opening’s diameter and the mixing tube’s diameter, the stronger the vortex created. Secondly, the shorter the length of the funnel the greater the drop in air pressure it creates at its opening. This drop in the pressure of incoming air is not sufficient to create a problem in naturally aspirated burners, but the low-pressure zone created at the opening with moving impeller blades, can draw some fuel gas back into the fan. Then, the fan’s electrical sparks will ignite the fuel/air mixture. So, a maximum 3:1 ratio between entrance diameter to the mixing tube’s internal diameter, becomes the first safety margin with fan-induced burners; another safety margin is provided with sufficient length in the funnel shape, or the addition of a short tube section between the funnel opening and the fan; this produces the same effect as a longer funnel shape (in avoiding back-flow of fuel gas into the fan). The SE HQ93 Stainless Steel Flask Funnel is an excellent example of such a shape being available as a safer air entrance for use on fan-induced 1/4" burners. Note: The moving fan blades you are concerned with here are impeller blades, which have become standard on axial computer fans; not the old-style flatter blade designs that are meant to push air forward; those increase the pressure of incoming air. Impeller blades lower the pressure of incoming air. This leaves us wondering how long a funnel is long enough. Only experience can answer that question, but I suggest a minimum length of one and a half times the diameter of the air opening. Furthermore, fan strength, constrictor shape (straight, convex, or concave wall) all come into play. Add to that how much curvature at what point in a funnel shape, and we are reduced to trial and error. Always remember that, if the burner you design starts backfiring into its fan, there is very little work needed to change it over to a naturally aspirated design. You do not have to rebuild the whole burner.

Stainless steel tube is the easiest choice to work with for any burner tubing part (although schedule #40 steel pipe nipples from a locale hardware store is cheaper); and it is the choice that is demanded for at least the outer tube of your burner’s flame retention nozzle. Since, in either case you will be unlikely to match up that outer tube with the nozzle’s spacer ring, and then the ring with the mixing tube for a sliding fit, it is good to know that up to a 1/8” a gap between outer tube and spacer ring, or between spacer ring and mixing tube can be easily tolerated.

Okay, yes, you can certainly improve on that flame. I will let Frosty talk you through that; it's his burner design. But, I suspect that you have interference with the flame going on by the surrounding refractory.

The most common source for thin wall capilarry tube is hypodermic needles; these come as two different types; sharps (used on medical syringes), and blunts (used on industrial dispenser syringes). You are far better off buying dispenser needles, rather than using medical needles, because dispenser needles are much more likely to have the nominal inside diameters expected in their gauge size. Medical needles are as likely as not to be extra thick or extra thin walled, leaving you guessing about their inside diameters . Dispenser Needle sizes: #14 Gauge is 0.072” (1.83mm) outside diameter by 0.060” (1.54mm) inside diameter. #15 Gauge is 0.065” (1.65mm) outside diameter by 0.054” (1.37mm) inside diameter. #16 Gauge is 0.064” (1.63mm) outside diameter 0.047” by(1.19mm) inside diameter. #18 Gauge is 0.050” (1.27mm) outside diameter by 0.034” (0.86mm) inside diameter. #20 Gauge is 0.036” (0.91mm) outside diameter by 0.025” (0.63mm) inside diameter. #21 Gauge is 0.033” (0.83mm) outside diameter by 0.021” (0.53mm) inside diameter. #22 Gauge is 0.027” (0.70mm) outside diameter by 0.017” (0.43mm) inside diameter. #23 Gauge is 0.025” (0.63mm) outside diameter by 0.014” (0.35mm) inside diameter. #25 Gauge is 0.020” (0.53mm) outside diameter by 0.010” (0.25mm) inside diameter. #27 Gauge is 0.016” (0.42mm) outside diameter by 0.008” (0.20mm) inside diameter. MIG contact Tip sizes: Tips for .023” welding wire have a .031” nominal through-hole diameter. Tips for .025” welding wire should have a 0.034” nominal through-hole diameter. Make sure that you aren’t being sold .023” tips as .025” tips. Tips for .030” welding wire have a 0.038” nominal through-hole diameter. Tips for .035” welding wire have a 0.044” nominal through-hole diameter. Tips for .040” welding wire have a 0.048” nominal through-hole diameter. Tips for .045” welding wire have a 0.054” nominal through-hole diameter. Tips for .052” welding wire have a 0.064” nominal through-hole diameter. Tips for .062” welding wire have a 0.070” nominal through-hole diameter. Just because there is a welding supply store in your town doesn’t mean that they will have the MIG tips you need in stock, or that they will bother to sell you one or two of them at a time, even if they do. Your sale is hardly worth their paperwork. You can buy MIG tips on line as few as five at a time for less money than they will cost at your local welding supply store, and chances are that the shipping charge will amount to less than the gas you may waste receiving a rotten experience, trying to buy them locally. On the other hand, you may do just fine at your local store. Some stores are starting to sell popular tip sizes in packages of five, from prominently displayed racks.

Well, one thing even a video can show, is that the forge interior is quite hot. There isn't likely to be any major problems going on with the burner, with such a good result. What Frosty wants is a flame photo, so that we can see if there is any fine tuning left to do, but you're safely in the ballpark BTW, know that you will actually be using that forge, I hope you are no longer using an Acetylene pressure regulator, and definitely not an acetylene fuel hose. I have listened to torch repair experts disagree on the possible dangers of using a MODERN acetylene regulator with LPG, but they both agreed on not using an acetylene fuel hose with LPG. Hose fires are soooo depressing.

Frosty summed things up nicely. I will only add that the second photo also shows a reducing (fuel rich flame); the difference is that it isn't heavily reducing, but what I consider lightly reducing. Many smiths prefer their burner flames set this way in a forge; I don't. But I prefer brazing with such a setting.