Mikey98118 Posted September 29, 2022 Author Share Posted September 29, 2022 Commercial forges recommended by Mikey (A) For a first forge the beginner isn't going to find a better dollar value than the single burner Mr Volcano. There is no better bang for the buck, and it is quite hot too. (B) Diamondback forge (single burner) is a hot moderately priced forge that is famous for holding up well for decades; "it takes a licking and keeps on ticking." (C) Chilly Forge is what you want after your hobby turns into a business, and production time becomes important. Quote Link to comment Share on other sites More sharing options...
BayardStrachan Posted October 7, 2022 Share Posted October 7, 2022 First long firing of my forge, and after about an hour, the shell started to bulge out at the front, opening a gap about 7 odd mm, the issue is that there is no other coating of the kaowool apart from the refractory cement. Is it still safe to use like this, or should i get rid of the gap somehow. One of the engineers at work was watching and had an idea to use som very high heat resistant stainless steel to line the interior of the forge, welding it around the openings, and leacing a hole for the burner. I dont really know if that would work but just an idea that surfaced. Quote Link to comment Share on other sites More sharing options...
Frosty Posted October 7, 2022 Share Posted October 7, 2022 The heat from the forge is warping the shell at the opening. If the gap remains open when it cools painting the Kaowool with Plistex as deep as you can reach with a brush should do it. This kind of warping is common enough, maybe someone else will chime in with how they deal with it. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted October 7, 2022 Author Share Posted October 7, 2022 If the shell is bulging because of the heat is warping it, the simple solution is to cut a slit in the middle of the bulging area; this will not harm the shell's structural integrity, and should stop the deformation. So now you know what and where. The next logical question is how much. It is safe to assume that a little deeper than the area of the bulge will be needed. So, start by just cutting a slit in the shell in the center of the bulge, and 12mm beyond the bulge; this should do the trick. If not, then slit a few millimeters at a time, until the bulging stops. the next logical question is how thick a slit. Watch the area of the slit when your forge is heated. If the edges of the slit touch at heat, widen it gradually, until they don't. Simple solutions are best Quote Link to comment Share on other sites More sharing options...
BayardStrachan Posted October 10, 2022 Share Posted October 10, 2022 I tried to cut a slit and the didint quite work, so I just made a sloppy mix of refractory cement and poured it in there. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted October 10, 2022 Author Share Posted October 10, 2022 Whatever works for you is fine with us. Lots of readers will be interested in how your fix works out Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted October 21, 2022 Author Share Posted October 21, 2022 On 10/10/2022 at 12:11 AM, BayardStrachan said: I tried to cut a slit and the didint quite work, so I just made a sloppy mix of refractory cement and poured it in there. How is your fix working out for you? We loge follow ups. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted October 21, 2022 Author Share Posted October 21, 2022 Tough enough? This is usually the last question people ask about their forge doors, but it should be the first. It's no secret that I have recommended high alumina kiln shelves as forge floors and doors for over twenty years. "Circumstances (always) alters cases." Improved refractories, Morgen K26 insulating fire bricks, and better reflective coatings on one hand, and increased prices for high alumina kiln shelves make them less attractive than they once were...as forge floors. However, their great toughness at incandescent temperatures keep them the number one choice for forge door inserts. For those lucky enough to have a large specialy store, such as Seattle Pottery Supply, there are yearly sales of broken kiln shelves at steep discounts; this is especially valuable for buying material for forge doors. Just by looking into the bin of broken parts, we are likely to start scheming on advance forge designs Quote Link to comment Share on other sites More sharing options...
BayardStrachan Posted October 21, 2022 Share Posted October 21, 2022 1 hour ago, Mikey98118 said: How is your fix working out for you? We loge follow ups. Haven't had a chance to fire it up yet unfortunately Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted November 3, 2022 Author Share Posted November 3, 2022 Angle grinder common sense I remember Makita starting the small angle grinder revolution back in the early nineteen-eighties when they brought their 5", 4-12", and 4" angle grinders in quick succession; their 4" grinders were considered a little under powered for heavy steel work, and suffered from the high prices charged for their grinding discs. It was probably that short sighted pricing that caused the market to prefer 4-1/2" angle grinders. However, 4" flap discs, which are superior to grinding discs, are a cheap and easy alternative price gouging, nowadays. Over the intervening years, constant sales pressure have turned the perfectly adequate 4-1/2" angle grinders of those days into over amped monsters today. It is bad enough to grind with one of them, and quite dangerous to use one of them with a thin cutting disc. Fortunately there are still 4" angle grinders available; I just purchased a 3M 4" grinder through Amazon.com. It has power equal to one of the original 4-1/2" grinders, and a 10mm spindle; these allow you to mount a low cost drill chuck on an angle grinder and use it as a right angle die grinder. Thus, for about $50 total you end up with all the tool you need to cut, grind, and sand steel forge parts, including the shell. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted November 27, 2022 Author Share Posted November 27, 2022 FEBTECH - Propane Gas Forge Single Burner I ran across this littl $76 oval forge on Amazon forge pages. Since ihis is a knife maker size oval forge, and costs less than I could by its parts for... And since one of the pieces of equipment I must buy or make, to stuff a new series of miniature burners into will be this size and shape... And since it will make a perfect little garage heater this winter, will build burner parts, I purchased one; it is due Friday, but since it hasn't even shipped yet, we'll see. I promise tp give a totally ruthless evaluation of it Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted November 27, 2022 Author Share Posted November 27, 2022 Yes, a lot of little forges come and go in the market; those that survive usually start raising their prices a lot in their second year; all the more reason to pay attention. On the other hand, helping the losers to exit the marketplace is a public service Quote Link to comment Share on other sites More sharing options...
Frosty Posted November 29, 2022 Share Posted November 29, 2022 I like the looks of the burner on the Fast Melt propane forge. Any thoughts? Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted November 29, 2022 Author Share Posted November 29, 2022 To start with; a confession. I input "the Fast Melt propane forge" on the Amazon.com search page, and on the Google search page and got nowhere. So, unless you can email their address to me, no answer to your question is possible In general, I have found that some of the latest burners that people come up with seem to burn much hotter than I ever expect. Unless I see a design flaw that is guaranteed to ruin burner performance, I have a wait and see attitude. On the other hand, anyone who believes the 'flames' shown in most burner adds must not have heard of Photoshop It has been hilarious at times to see the identical Photoshoped baloney flame supposedly coming from various Chinese drop shipper ads for air-butane and air-propane torches Quote Link to comment Share on other sites More sharing options...
Frosty Posted November 30, 2022 Share Posted November 30, 2022 I couldn't find a site with the name either so I PMed the pic and link because I can't tell if it violates the rules or not. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted November 30, 2022 Author Share Posted November 30, 2022 This is a very old burner design; When coupled with a fan, it is pretty standard for gas heated kilns and hot gas working equipment. What the fan blown version is basically good for, is creating soft enough flames on gas heating equipment, so that an automating gas shutoff system can be run from a pilot flame; this is waaaaaaaaaay cheaper than black light or other modern safety shutoff systems are; most of those cost more to buy than a kiln, glory hole, or day tank is to build. Gibberson Jr. patented the first multi-flame ceramic burner head to make an end run around that problem back in the nineteen-sixties, because he made his own burners, rather than just buying fan-blown burners. Anyway, his ceramic heads were a screaming success, as they turned out to be very efficient. On these older burner designs, a miniature burner is slung below the fan-blown burner, or a burner with a multi-hole ceramic head (usually on the same kind of fan-blown burner body) to provide a pilot flame for the shutoff system. I think it would also work on a ribbon burner, and have long wondered if a "T" burner that is fitted out with one of the classic flared flame retention nozzles might be able to run a pilot flame system successfully. Quote Link to comment Share on other sites More sharing options...
Frosty Posted November 30, 2022 Share Posted November 30, 2022 Boy do we have different opinions of a full length taper mixing tube! A flare nozzle is a relatively recent thing, say 20-25 years. It's not necessarily a good thing but it's doable for a home built burner. I think it's unconscionable that commercial burners are being made from plumbing instead of using designs that have been in service for hundreds of years. Without need for a blower. If you have to put a blower on a NA burner its either badly made or you're doing it wrong. The pic I sent may be a lousy burner but it's at least designed as it should be, the execution may suck of course. The T burner is anything but high performance, it's easy to make and works okay. I'm shocked it works so well on ribbon burners, you are aware it's driving about half the outlets an inducer that size should. Yes? One of the things the accident put probably out of reach was my desire to set up a spinning lathe and make linear burners like they should be. Trumpet intake, proper wasp wasted "throat" and a mixing tube tapered less than 1:12. In the old days the only place you saw plumbing part "burners" were on ranches usually used to heat branding irons or burn weeds. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted November 30, 2022 Author Share Posted November 30, 2022 1 hour ago, Frosty said: Boy do we have different opinions of a full length taper mixing tube! I am not speaking about mixing tube lengths at all; it's the other end of the constriction I'm concerned with. If you want a strong linear burner, the diameter of its air opening should be a minimum of 2.5 times the diameter of the mixing tube. With the strong breaking forces available in a tapered mixing tube, I would double that figure. Do I think that fully tapered linear burners still have an important niche in burner design? Absolutely; however, only someone into 3D printing is likely to be able to pursue them these days Someone quite stubborn could construct a usable spinning lathe, and learn to operate it. But then would come the rather high cost of sheet-metal for each and every burner design experiment. Plumbing parts and steel tubing can be handled with hand tools, which are well within a novice's reach. As to flare versus slide-over stepped nozzles: Let the nozzle match the burner design. One of my favorite flame photos came from a classic flared nozzle design on a "T" burner. I term them classic to distinguish them from the nozzles with radical tapers that have been peddled in the last four years. 1 hour ago, Frosty said: The pic I sent may be a lousy burner but it's at least designed as it should be, the execution may suck of course. Without seeing the forge running, we can only dare to state that the burner might suck 1 hour ago, Frosty said: The T burner is anything but high performance, it's easy to make and works okay. I'm shocked it works so well on ribbon burners, you are aware it's driving about half the outlets an inducer that size should. Yes? Yes, but then the difference between under-powered and flame extinguishing mixing flow is so small that I have wondered for years why builders resort to such strong motors on fan- blown forges... Quote Link to comment Share on other sites More sharing options...
Frosty Posted December 1, 2022 Share Posted December 1, 2022 1 hour ago, Mikey98118 said: the diameter of its air opening should be a minimum of 2.5 times the diameter of the mixing tube. With the strong breaking forces available in a tapered mixing tube, I would double that figure. Without being able to measure it the best we can do is estimate and it sure looks like the intake diameter is at least 4-5x the throat. One of the old commercially made linear burners were way stronger than the 3/4" to 300-350 cu/in forge rule of thumb. The throat dia. in the one that heated the pan in the asphalt patch truck at work was maybe 5/8" dia. and heated a 4' x 8' steel pan and we had to keep it turned down to maybe 2psi. The main reason I got involved with it was the mechanic couldn't get it to work properly, he kept turning up the psi which made it worse. Spray off the truck tires had all but completely blocked the gap in the choke. AND because some genius used a weed burner to heat the burner the road dirt was baked hard so I had to take it apart. I cleaned the throat with my index finger which is about 5/8" where it wanted to get stuck. The output end was about 2 1/2" dia and the gap in the choke plate was less than 1/8". The heat tube under the pan is a "ribbon" burner a piece of 2 1/2" pipe with a piece of 3/8" IIRC pipe every few inches alternating 45* forward and backwards. The ones on one of the club member's forge are much smaller but hold the same ratios and either one will bring his forge to welding temp easily the OD at the throat is maybe 1/2" and Mark wouldn't let me take one apart even if I asked him. Breaking forces? You lost me. What makes a linear burner that follows the established design and ratios so strong is how strong the low pressure zone down stream of the throat is. You don't need very much intake diameter if it's feeding a near vacuum. My inability to come close to commercial linear burner performance is where the T Jet ejector came from. The only reason a jet ejector made from plumbing is acceptably efficient is because commercially, jet ejectors are vacuum pumps. Even a home made one develops enough low pressure differential to burn a decent amount of propane per second. 3D printer? Are we talking commercial or home built? No sheet metal required or wanted to spin burners and not something someone is likely to tinker together in their garage. I grew up in a metal spinning shop, know how split tooling works and how to spin tubing. I wasn't a proper metal spinner, before I got large enough to pull the tools, OSHA and the insurance company told us I could NOT even set foot on the floor. Still I know the dance well enough to make it work. If I were going to make them from sheet I'd stamp and crimp the halves together like they did until recently. You see sand cast aluminum products like in the Fast Melt picture because they're really cheap to make if you're paying unskilled labor a couple dollars a month to ram up molds. Were I producing them commercially it'd be on CNC spinning lathes feeding high temp alloy stainless steel tubing through the spindle, dual rollers and I bet it wouldn't take heat. The next step would be crimping the jet and choke plate assembly on the intake end and off to clean up, inspection and shipping. That Fast Melt forge burner is just the first one I've seen in quite a while with a trumpet cone intake and full tapered mixing tube. No idea is it's worth spit internally, like you say I haven't seen it burning. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted December 1, 2022 Author Share Posted December 1, 2022 I think our views on gas orifice size versus throat (restriction) diameters are on the same page; they only depart somewhat when the restriction becomes a tubular shape (mixing tube), and then only because such tubes are more affected by burner flow speeds, which are inherently different in different burner designs. 1 hour ago, Frosty said: What makes a linear burner that follows the established design and ratios so strong is how strong the low pressure zone down stream of the throat is. You don't need very much intake diameter if it's feeding a near vacuum. The difference in our thinking here is that I'm not concerned with the air opening and restriction ratio to draw intake air. I am far more interested in a linear burner's ability to create vortex flow, having found this motion to create the most expedient conditions to super-charge burner performance, overall. I am actually enthusiastic about the potential of this shape in burner designs. But only if new versions of this design are experimented with; not old designs that were thought up for yesterdays limitations. "And there's the rub." Not in building a single burner, but in building many individual burners to experiment with. The determined can build this shape in aluminum from sand castings; they can be created from ceramic by potters, and refractory cemented to refractory burner heads, or slip molded for ceramic production models. But differing individual models for a series of experiments? Ugh; that's a hard climb...thus the mention of 3D printers, such as Another Frankenburner has been successfully experimenting with These are the burners of the future, but I only try to write up possible paths for novices to tread; most of them think small power tools are a reach. Quote Link to comment Share on other sites More sharing options...
Hefty Posted December 1, 2022 Share Posted December 1, 2022 Mikey and Frosty, do you think notched "cut and shut" pipe methods could be used to make decent burners with tapered intakes and mixing tubes? I've seen youtube videos on this sort of method on a larger scale in the past (when I knew a lot less about burners) but I wondered if the inside would be too "chunky" to get good vortex mixing on smaller burners? Quote Link to comment Share on other sites More sharing options...
Another FrankenBurner Posted December 1, 2022 Share Posted December 1, 2022 All this burner talk in the forge thread. This is the 101 material? The wife says when she starts to smell smoke, she knows I'm a million miles away going a hundred miles an hour. I have just recently started playing with burners again. I stopped tinkering for a while. The burner was working so well that it was time to take a break to spend more time swinging a hammer. The burner I have been using is the 3/8" nominal (0.675 throat) burner head on a tapered mix tube with a large step nozzle. It has been working great. The tapered mix tube made a giant leap in induction. I had to choke the burner down as it was too oxidizing to forge weld which means I get to play with orifice size some more. I am very pleased with the burner. I have started on my next adventures which are tapered mix tubes feeding multiple ports. NARBs, shower heads, simple splitters and whatever else comes up. Using the "burner" as an inspirator. A fuel air pump. I have not played with the tapered tube and the manometer enough to speak with experience but in my current mind's picture of things, the tapered mix tube's purpose is to do the opposite of what the throat is doing. The throat constricts, causing an increase in velocity and a decrease in pressure. We want the low-pressure zone to induce air. The tapered mix tube is decreasing velocity to increase pressure. Instead of relying on the velocity of the FAM, we are increasing its pressure from the low-pressure zone in the throat. In my little bit of playing with NARBs, without the tapered tube, there is a large discrepancy in stream velocities across the ports. Faster velocities nearest the edges. I think the FAM is coming into the plenum at high velocity/low pressure and anywhere that it slams into a wall and slows down, it increases in pressure (inefficiently). If my thinking is correct, using the slower higher-pressure FAM coming from a venturi will cause more even velocities across the ports. It would allow the burner head and mix tube to act as a FAM pump, an inspirator. You could also push FAM around some bends, down longer sections of pipe, etc. Sacrifice some throughput for orientation options or port configurations. Time to stop talking and start experimenting. Maybe I can prove all that wrong and update my thinking. Quote Link to comment Share on other sites More sharing options...
Frosty Posted December 1, 2022 Share Posted December 1, 2022 Jono: The only problem with the cut and close method is how well you can lay out the cuts and how cleanly you can weld them. I gave it a shot a long time ago but wasn't up to it nor willing to make enough prototypes to get it right. I was also looking for minimal equipment and shop skill builds so it didn't fit the criteria. Uh. . .Yeah but the thread started out talking about forges but drifted a little. I tend to agree with your reasoning on uneven NARB flames and came up with two solutions but haven't tried either. First was to put a strip of steel that ran full length of the plenum less than half it's width above the supply port. The idea being the FAM would be bisected by the "baffle", deflected towards the ends and spill over the edge more evenly than a free flow. The other idea was to use 2" x 4" rectangular plenum with the supply port as far from the burner block as possible. I haven't tried either, heck I haven't built a burner in quite a while. Frosty The Lucky. Quote Link to comment Share on other sites More sharing options...
tinkertim Posted December 1, 2022 Share Posted December 1, 2022 Glad to have you back Frank! I've still got some backburner projects to do, including a 3D-printed burner, but I need to play some more with my free CAD software, to get the spiralling aerofoil profiles how I want them, using your vortex injectors as a starting point. I'll get there......one day! Quote Link to comment Share on other sites More sharing options...
Mikey98118 Posted December 4, 2022 Author Share Posted December 4, 2022 Members 6k LocationSeattle, WA Author Posted November 27 FEBTECH - Propane Gas Forge Evaluation This little $76 oval forge is featured on the Amazon.com forge pages. Since ihis is a knife maker size oval forge, and costs less than I could by its parts for it looked like a nice choice of temporary garage heater, that could be changed into a picky-butt-approved oval forge to stuff miniature burners into, and so it is. Furthermore, it arrived on time, and their packing job was superb; there should be no worries over shipping damage. As to its use for a garage heater...maybe. And as to its probable use as a forge; probably not. To begin with all of its mild steel parts have a very nice paint job on them; but I don't think it is heat resistant paint (I could be wrong on this). The burner is well enough constructed, but poorly designed, having air holes instead of slots. Fortunately, these holes or all in line with each other, so they can at least be turned into slots. The burner's gas assembly is good enough, but ends in small gas orifices of the kind found on turkey friars, etc.; their orifice diameters are too large for my liking. However, they can probably be replaced with 3D printer nozzles, after a little re-drilling and tapping of the gas tube. The choke sleeve appears to be designed to be revolved, instead of sliding back and forth; it should be replaced. I haven't run the forge yet, but the gas regulator appears to be of excellent quality. The ceramic wool is good quality, but the refractory is only rated for 2750 F. Plistex 900 would be way better. In other words, this little guy is good for parts, but as a working gas forge...spend a little more money and get a Mister Volcano. Quote Link to comment Share on other sites More sharing options...
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