Mikey98118

Charlotte, Now that's what I call an impressive background!

A "T" burner will have completely different dynamics from one of mine, so most of the advice I can't comment on, but you definitely DO NOT use the same diameter gas orifice in two different burner sizes.

I'm simply not that trusting of foreign made tools. An American manufactured tool exposes the manufacturer to devastating law suit losses, if the tool is defective and proves dangerous. But, try suing a French manufacturer in a French court "Yankee"! So, when I see normal safety concerns ignored by a manufacturer, who is beyond retaliation, I "just don't go there."

To all here, You don't have to buy my book to discuss it knowledgeably; in 2006 it was pirated and elctronic copies of it are still available "free" all over the net. At one point I counted 120 different sites offering free downloads; a few of them can even be trusted! And why would I mention this? Because my original contract expired; the guy who bought my publisher out sends me royalties in return for the PRIVALEDGE of publishing it, but I have no contractual obligations to him. Besides, book sales have nearly doubled since it was pirated! Just input Gas Burners for Forges, Furnaces, & Kilns followed by PDF. The percentage of people who felt they were getting full value for money spent always bought their own copy, and others never would. Pirating has more than repaid a few lost sales in maximum free advertising. Seldom does something good for so many come about from such bad intentions on the part of a few :-)

You're welcome, MP. Hope you've been following along recently on all the gas forge discussions, If so, you'll already know that you want to buy extra MIG contact tips and insert .028" inside diameter dispenser needles into them. You will then have the ability to fine tune the forge even further; not that you won't also want a pair of .023 MIG contact tips with the original .031" holes left as they are, to give a slightly softer flame for forge welding. What you will not have heard, because it is only mentioned in the updated version due out next year, is that I've modified my original advise about employing 4-1/2" angle grinders for all the work, to include hand held rotary tools for cutting out the air openings. In 2004 these tools and their accessories were just too expensive for most of the starving artists the book was dedicated to; today this isn't true. If you feel that both tools are too great an expense, choose the rotary tool over the angle grinder. Also Dremel's 1-1/2" spring loaded EZ mandrel, unlike much of their overpriced stuff, is worth every penny on this kind of work.

I've looked at the photo, and it seems unlikely that uptake of exhaust gas into burner intakes is the problem; not with the burners offset like that. But, he doesn't say whether or not the burners have flame nozzles attached, so lack of sufficient back pressure just could be his problem. I think the addition of flame nozzles will prove to be the simplest solution for it. Of course your idea of redirecting exhaust gas further away the the burners with temporary structures is painless enough to be worth doing, just to eliminate the possibility. Stuffing a firebrick under the burners within the furnace should be a fairly painless way to check out the back pressure possibility, too.

The ignition temperature of propane is 470 C; well below even the heated air figures, so I would not trust the safety of this tool.

Frosty, i should have pointed out that MIG contact tips are labeled according to the wire size they feed. .023 contact tips are sized to feed .023" MIG wire; their actual hole diameter is .031" to buy something with a hole diameter of .028" or smaller the builder must use capillary tube, buy a standard gas jet (too short), or drill the hole smaller, and then employ torch tip cleaners to smooth away internal scarring, while bringing the hole up to finish size. So, if a person wanted to improve an existing 1/2" burner with minimal trouble, they would buy capillary tube in the form of a dispensing needle from eBay, drill out an existing .031" orifice a few thousandths, insert the needle into it, and swage the copper MIG tip down tight around it. Afterward it could be screwed into the burner's gas pipe just like the tip it was replacing. Do not increase hole size in copper more than a few thousandths at a time or it will cease the drill bit and snap it off.

Frosty, I know you didn't, but most of what I explore these days are post publishing discoveries, and the main value of the book is all those piles of background information that most people who've built forges already found out the hard way. I wrote the book for art majors who are being cheated by our not so wonderful school system, and who discover the hard way--after graduation--that they don't posses the tool skills to do much with their 'education.' That was my mission, but once it was accomplished I was free to pursue more advanced methods, which take basic shop skills to employ; much more fun.

Charlotte, In the first place, congratulations on accomplishing a very difficult task; especially if you are getting the resultant gas jets long enough. But a twist drill will leave internal scarring in the hole, which will interfere with with laminar flow in the gas stream (a definite no-no). You will find capillary tube to b e more efficacious, and a lot easier to deal with in future. Frosty, There is a lot to be said for using a jewelry torch to heat coffee-can and smaller forge sizes. But the torch nozzle will overheat and become an expendable, unless a flame nozzle is attached to it.

Thanks, Sharpshooter, I do love hearing specific details on a new (to me) subject.

"Absorbs the heat" is correct, but can be taken the wrong way too easily. Some chemical recombination actually produces heat; its exothermic. Single hydrogen atoms combining into molecular hydrogen (H2) in an atomic hydrogen flame produces a lot more heat than oxyacetylene combustion for instance. Other recombination will absorb heat; its endothermic. As to why methane's recombination of hydrogen and oxygen atoms into water vapor in the secondary flame would absorb heat so much more than any other fuel gas, I don't know; just wasn't that interested. I'm basically ruthless about tools. I care how well they do a given job, and don't do more than minimal research as to why something is so, once I know that it definitely is so.

Frosty, All that information and I didn't directly answer your questions. Yes, different burner sizes are that important to people working other aspects of the metal hobbies. But, the main thing about Luer-lock dispensing needles is that between the gauge sizes available and the changes in orifice diameters because of wall thickness an exact match between gas accelerator and burner can be made. This will allow the long gas tubes to be deleted from jet ejector burners. I like compactness in a burner.

MP, When it comes to installing burners in a gas forge, they are interchangeable, so nobody says you need to build one of my burners, to begin with; not even me. The burners being sold on eBay at present are bargain priced and work reasonably well; there are many other choices as well. You don't have to build a Mikey burner to get your money's worth out of the book. Life is about choices; therefore options are a very fine thing. Of course, you probably will build one in the end :-)

Two 1/2" burners on a five-gallon forge will give more even heat than one 3/4"; on the other hand, the single burner will heat up most of the forge just fine, and produce less heat loss for gas used; why? Because of the kiln shelf in my design. Leaving the outer inch or two of the forge at a lower heat means less conductive loss via that shelf. Some people use a thin brick and don't extend it outside of the forge, but this makes a weak construction choice. In my next portable gas forge, the kiln shelf will extend even further outside the steel shell. this will be done in order for it to hold a sliding baffle plate, and will be featured on an oval forge, instead of a tube forge.

Advising people to check things out with their local propane supplier is more palatable than advising people to check with their local Fire Marshal, since calling on the fire department for advice alerts local authority to what you're doing, but my advice is to involve them in your plans from the very beginning. Most people fear that they will nit-pick and interfere in every way; they have better things to do. The more likely problem is likely to be a reluctance to advise you at all.

Safety regulations agree with your choice. Propane cylinders are supposed to be kept outside of a shop, with the gas piped inside or carried in a fuel hose. A propane cylinder is never supposed to be positioned near to the forge. You're also right about two regulators, although you can fine tune gas input with a fuel rated needle valve effectively and safely, if you have a regulator at the cylinder end of your hose to keep gas pressure on your hose and gas fittings limited.

tony, It seems clear that the outside chamber and air feed system (fan, etc.) for a ribbon burner will require a fair amount of space and a rigid support structure, so you might as well build a small table for it to sit on. what kind of forge do you place on the table? brick pile or square seem the practical choices.

Buzzkill, I just wrote you a lengthy reply, which promptly disappeared into cyberspace when I pressed "Submit Reply." So this one will be short. Methane is rated about one-half as effective at heating as other fuel gases. Water formation in the secondary flame is the reason given for this inconvenient fact. I've used methane heating torches, which put out really impressive looking flames, and can tell you from first hand experience that the poor heating performance quoted is so. This information is all available on the web. Mikey

Frosty, I think we're talking apples and oranges. For one thing you seem to be thinking along the lines of vortical flow in an expanding tapered mixing tube, which will produce some effects that I'm speaking of, but will reverse others. I'm recommending producing spin (not push) at the large opening of a funnel; that funnel's small opening connects to the rear end of a burner's mixing tube. One facet of vortical flow (speeding forward motion of the mix my way, and slowing it your way) are opposite effects of the same principle used in reverse; same principle but different applications. Better mixing and and lowered flame nozzle pressure will happen both ways. I don't find one method superior to the other; I see both of them proving useful, so long as they are applied deliberately. Mikey

Charlotte, Methane's theoretical flame temperature is nearly the same as propane; not its proven heating value, which is about one-half. Both the CO and H2 combustion are heat producing, so minor heat is added in the secondary flame. Formation of the H2O leaches heat from the secondary flame; it does not produce heat.

What I like best about this group is the fresh ideas it inspires. This summer I will have to build another brick pile forge (in the heavy table this time), and install a fan-blown ribbon burner in it. Speaking of fresh ideas, its time to point out some advantages of oval forges over tube forges; they are built to provide additional width inside, but can be run with interior baffles to save gas when heating narrow stock. Yet oval forges are better than square forges because, like tube forges they will naturally shed heat from their bottom side as well as the top side, so that there is reduced heat transfer to a table top. So, why should someone claiming to have designed a powerful new kind of burner be interested in ribbon burners? Because I don't believe in an "ultimate" burner design, and don't even want there to be such a thing (Viva variety). At least one manufacturer claims interior equipment temps of 2700 degrees, and several sources claim excellent "hang time" for combustion gas, along with low noise levels. Anyone primarily interested in equipment design, and claiming to have an open mind, should be willing to investigate such claims, whether doing so is personally convenient or not.

Mine was built more as a movable hot-work surface where small welding and brazing projects could be done in a garage or off-site, but one of the abilities it has is to be used as a base for brick forges. It has UK style double gas outlets controlled by ball valves, twenty-five feet of 1/4" fuel line stripped from a torch hose, steel wheels, and a bottom shelf to store the five-gallon propane cylinder and a water tank; it also has a 3000 degree kiln shelf top supported by insulated fire brick over a layer of calcium silicate board, which "floats" on a thick layer of Perlite. The table top is 6" thick in all, and super insulated. There is a built in torch portal of 3000 degree castable refractory that can hold up to a 1" pipe burner. The whole thing could easily be lifted onto my truck bed as it doesn't weigh over thirty pounds stripped down, and all the "stuff" it carries can then be installed with it in place. The cart also features a built in variable height swinging insulated lid, so the forge can easily be used with brick for heating large scrolls and circular designs. That is the beauty of a configurable (brick pile) forge; endless accessories can be added to it for convenient heating of darn near anything, and it can be wheeled over to a corner of the shop afterward. The cart has been used for night classes at some working historical site in Maryland since 2006 along with all the other gas burner equipment that we demonstrated at the ABANA Conference in Kentucky that year. I now have a heavy duty hard fire brick work table, but then welding and brazing are more important aspects of equipment R & D than forging is; I do a lot more of that than wrought iron these days, being an old guy and all :-) Frosty, The way we missed connections was that you and Ron started out a few years ahead of me. I originally was gearing up to do wrought iron, after the shipyards in Seattle dried up and blew away, but health problems cancelled all that and left me with a lot of time for research. Originally, I started designing burners that would run completely clean in a gas forge, hoping to salvage some part of my plans, but never could recoup enough health for it, and drifted into writing instead. I imagine you felt just as stubborn after your accident, and Ron did after his long bout with pneumonia, but all three of us learned that we got old sometime while we weren't looking...bet ya every generation learns the same lesson, while "going down kicking and screaming" about it, yes? Mikey

The mortar will work fine IF you use rigidizer on the ceramic blanket first. Most rigidizer is colloidal silica (better known as fumed silica), a light inexpensive product to have shipped through the mail; colloidal means it will stay suspended in water, which carries it well into the fiber blanket. Add a little food coloring and you can see how far it is penetrating. Let it dry and then fire it hard, before adding the no more than 1/4" thick layer of mortar. Yes, definitely paint the mortar with ITC-100; the fuel you save will pay for it in a few months. Have fun and stay safe.

Tony, The guys are giving you a lot of good advice. Mine is to hold your horses and do a little more research before you jump in and start building. No amount of questions and answers will set you up with all you need to know unless you plan to spend a couple of years asking them. You can buy books on the subject too, and they will help you ask the right questions in the first place. Try looking up gas burners or gas forges on Amazon.com in their book section. If you don't have a very good idea what you want to do with a forge, I would like to suggest to either deliberately start small, like with a knife making forge, or build a "forge cart" on which you can set up various insulated brick forge shapes, while making up your mind what you really want to work with. The advantage to these polar opposite pieces of heating equipment is that they both will get used even after you decide to build a particular forge for your own passions. The forge cart is also a usefull surface for doing welding, brazing, etc. For general gas forge shapes, you should at least investigate oval forges, before making a decision. Don't forget to include a kiln shelf floor in your forge, because all the insulating materials and thin refractory coatings being recommended to you won't take a beating or stand up to flux attack, and hard brick becomes a heat sink. While two inches of ceramic fiber is a good standard thickness, you want to install it as separate 1" blanket layers to avoid rippling in the finish surface. Ceramic fiber products de-laminate so easily that they need to be rigidized anyway. Then, of course we come to burners...:-) As to buy versus build, if you're running a business already, buy a good forge. Otherwise, build; it isn't just about saving money. When you build a tool you learn a lot about it.