Mikey98118

Good article, Frosty. This statement was what jumped out at me: "... which is one of the main reasons why much ceramic technology is based on the use of fine-particle materials."

An improved cast flame nozzle from your hardware store A page or two back, The Legend posted a photo of his first (?) burner attempt; and it is worth a second look-see, because, instead of screwing the pipe fitting that he used for a flame retention nozzle directly onto the burner's mixing tube, he screwed it into a short section of the next larger pipe than the mixing tube. In return for this extra step, his burner gained the ability to be tuned somewhat by moving the nozzle back and forth along the mixing tube; creating still another type of slide-over flame nozzle. While not my first choice for flame retention nozzles, cast iron pipe fittings serve many of the functions of nozzles, which are deliberately constructed for the purpose, including the ability to last longer than mild steel; they are cheaper and simple to buy, when picking up the other pipe parts at your local hardware store. Legand's additional step brings them much closer to being a practical choice.

Not very detrimental in such small percentages, and the zirconium silicate has such a high-temperature rating that Veegum's lowering to temperature use ratings are more than compensated by its likely being the only plasticizer and binder that will do the job?

That should have been near side, or burner side of the floor.

I think all the development going on is with its use as refractory; the reflective coating is pretty straightforward. The latest wrinkle seems to be trying to substitute cerium oxide for zirconium silicate; this is on another thread. I hope they decide to post on this thread when they feel ready.

Whatever kind of cast iron article you start with, you will end up with white hard cast iron once you heat it up like that. What does that mean; white hard? Think just this side of Stellite; think totally useless for anything. You wanna mess with steel...fine. Leave cast iron to professional foundry workers, who know what they're about.

Or crucibles for warm-glass projects, once it is converted by a gas burner.

The guy who came up with this trick (so far as I know) uses a rod connected to a reciprocating power hand tool. Lots of guys have built their own vibration pad by adding an off-center wieght onto a motor shaft, which is screwed onto a steel pan; low-tech is my favorite magic

Oh, that was good; snarky enough for a Brit!!! I loved it

I presume you already know about placing the wet tile on paper towels to help leach water from them while they are becoming greenware. You may not have heard about using vibration to liquify refractories with a lot less water...

When and if needed? Isn't a heat reflective coating always a good idea? Yup; but whether you add it right now or "someday" can be your personal choice, if you have a cast refractory hot face, but dut someday better come soon with a thin seal coating.

So far so good

A belated hanks, Alan. I intended to write back, but forgot to input the message

Floor flanges are excellent for mounting burners onto brick or cast refractory surfaces; to use one to mount a burner on a cylinder shape would be doing things the hard way, to the max! You want your flame to impinge either before or after your workpiece when possible. Keep mulling over what I wrote. Don't bolt your food

Burner Position: Why comes before where The first question asked about burner positioning should be why; not where; their positions are always derivative. NOT primarily for best circulation of hot gases; that is a secondary concern. Impingement comes first. The targeted point where a burner's flame strikes, must be physically tough and thermally up to wear and tear. If your forge insulation is only protected by by rigidizer and a thin seal coat, the flame needs to impinge on a high alumina kiln shelf or an exceptionally tough cast refractory floor (like Kast-O-lite 30). On the other hand, if the forge's hot-face is a 1/2" or thicker layer of Kast-O-lite, wall impingement is no longer a big issue; it's a minor issue, to be balanced against other concerns, and aided by re-emissive coatings; when and if needed. Only secondarily, comes circulation; fortunately, this takes nowhere near as much encouragement as commonly supposed. It is a strong natural tendency for the fame to circulate within most forge shapes, including box forges. In fact, the only burner position that would effectively interfere with the circulation of hot gases within a forge would be to aim the flame directly toward the exhaust opening! Note: Positioning burners near the front of a forge makes a close second to the previous example of bad planning. So, we see that circulation is a weak secondary concern, which should be balanced against other factors, such as how far the flame can go before impinging on first surfaces. With a hot-face wall that is only a thin coating, you must aim the flame to impinge on the cast refractory or kiln shelve floor. You would still want to avoid your workpieces, but would also want it to strike as far from the wall it will bounce toward at possible. In that case, I prefer to aim the flame at the near edge of the floor, with only enough angle to assure that it will bounce toward the far edge of the floor, and continue up the wall.

You asked for schooling on the subject, so here goes. The first question asked about burner positioning should be why; not where; their positions are always derivative. NOT primarily for best circulation of hot gases; that is a secondary concern. Impingement comes first. Where a burner's flame strikes, must be physically tough and thermally up to wear and tear. If your forge insulation is only protected by by rigidizer and a thin seal coat, the flame needs to impinge on a high alumina kiln shelf or an exceptionally tough cast refractory floor, like Kast-O-lite 30. On the other hand, if the forge's hot-face is a 1/2" or thicker layer of Kast-O-lite, wall impingement is no longer a big issue. Secondarily, comes circulation; fortunately, this takes nowhere near as much encouragement as commonly supposed. It is a strong natural tendency for the fame to circulate within most forge shapes, including box forges. In fact, the only burner position that would effectively interfere with the circulation of hot gases within a forge would be to aim the flame directly toward the exhaust opening! Note: Positioning burners near the front of a forge makes a close second to the previous example of bad planning. So, we see that circulation is a weak secondary concern, which should be balanced against other factors, such as how far the flame can go before impinging on them. With a hot-face wall that is only a thin coating, you must aim the flame to impinge on the cast refractory or kiln shelve floor. You would still want to avoid your workpieces, but would also want it to strike as far from the wall it will bounce toward at possible. In that case, I prefer to aim the flame at the near edge of the floor, with only enough angle to assure that it will bounce toward the far edge of the floor, and continue up the wall. With this in mind you tell me; how should you position and aim your burner?

I don't bother with pyrometers. Light yellow incandescence in the forge should be plenty of heat. If I were you, I'd look into all the other factors, such as what you are using for flux. Remember that Gas Forges is only one forum on IFI. Hunt as hard for welding advice as you did for advice on forge construction.

Hotter further into the forge; yes. I think you have some other problem; not temperature.

Yes!!! I had a buddy who tried to use air fittings on his propane forge. I was there when it caught fire in less than a week's use.

there is no mention of clamshell forges in this thread. Do any of you want them included?

I'm interested in that; could you clue me in as to where to look, please?

I think you have a lot of drive, imagination, and certainly good drawing skills. What you don't have is a clue why things work in a burner. You can build a good burner EXACTLY ACCORDING TO THE INSTRUCTIONS OF SOMEONE WHO DOES, or you can "wing it" successfully if you understand the why of burner design your own good self; one or the over. There are no shortcuts! Frosty has burner instructions, with drawing, on how to build his very hot burner. You even get to quiz the author. Larry Zoeller Forge has instructions and photos on his website; buy the way, he sells stainless steel tapered nozzles for eleven bucks. There is more than one kind of stainless steel tapered burner out there for sale. You should even be able to buy replacement nozzles for most burner sizes from Hybrid burners.com The minimum Two things you need from a flame nozzle is that it be made of stainless steel, and that, whether it is a traditional taper design (like Larry Zoeller's) or one of the recent short tapers, or even one of my stepped style nozzle, it needs to be a slide-over style (Thank you Latticino); not be screwed on. All I can say about your decision to add a stainless steel pipe unto the end of a minimally useful nozzle made from a pipe reducer is, "that was where you left the road completely."

Only twenty bucks a lb.? Actually, that is cheap. Now I'll have to take a second look at it for thin coatings zirconia is about ninety bucks a lb., and the stabilized version is a third more. For thin coatings(;ess than .040") is needed to use a re-emissive coating on a crucible. I think about more than forges

99 times out of a hundred, wire feed problems begin and end in the drive rolls and/or gun.

I have seen cerium oxide described as the best re-emissive agent and zirconium oxide as second best. Also, cerium oxide has no problems with phase shifting at various temperatures complicating its use in refractories. I never investigated it because I assumed it would be even more expensive than zirconia. zirconium silicate makes an end run around all zirconia's issues, so I looked no further.