Mikey98118

I should never have made that comment; it is true, but misleading. Have I mentioned enough times about being "a notorious picky butt"? To me a flame is either perfect or its something less. In reality a flame is good enough to serve well in your forge, or the burner maybe needs a little help. A normal human being would probably never notice the difference between the flame from a 1/2" burner, with an .023" MIG tip (.031" orifice) and the same burner with a MIG tip fitted with a capillary tube inside, which has a .028" orifice. Doing all that extra work can only make a hopeless geek happy. No, no! Don't listen to that slob! I, Dr. Frankenburner say you must do my burners just right!

Well, luck or not you have developed the knack of producing hot flames. As to the orange streaks; my belief is that they are from oxidation of the flame nozzle, which is why they are more severe with mild steel nozzles. In the past, guys have even found these streaks to be more pronounced with #304 stainless nozzles than with #316; in any case they do no harm.

"Galvanized" pipe fittings are a YES! Zinc coating, which is what "galvanized" usually means these days, is a good idea: unless the part is getting very hot. In that case, the coating can be stripped with a few hours in a pan of vinegar, or burned away in a charcoal grill. It is important not to say "no" to a source of threaded pipe fittings, in the face of ever shrinking sources. Furthermore, you are a lot less likely to end up with bottom-of-the-barrel fittings (with crooked threading), with a part you must pay a higher price for than in black pipe fittings.

Not really; in fact zinc coating. which is what "galvanized" usually means these days, is a good idea: unless the part is getting very hot. In that case, the coating can be stripped with a few hours in a pan of vinegar, or burned away in a charcoal grill. It is important not to say "no" to a source of threaded pipe fittings, in the face of ever shrinking sources.

Frosty, Just after I wrote you back, the Net go down.

Rigidizer is usually sold in one quart containers, which is enough to rigidize about two five gallon sized tunnel forge. Fumed silica is sold in much greater amounts. You are not likely to find other sizes available, so your question turns out to be a none issue. So, after being sidelined with a bad splitter, I'm back on line, only to see you others doing a great job, keeping up with the stickies.

Please understand that this burner has been modified with air slots; not air holes. What other changes have been made I don't know; but that is a big one. Frosty, I stand corrected.

Muffler forges are used to come up with a convenient shell to build into an oval forge; such a forge is meant to give a maximum amount of parts space in a small area; this is why the burner is positioned at an angle from one side of the forge; never straight in. Once you re-position the burner, that brick won't work either.

We all tend to forget that only refractories with high amounts of silica in them can be claimed as water resistant. High alumina kiln shelves have no more than trace amounts of silica, and therefore will absorb water vapor over time; they, as most refractories, must be forced dried before being taken to incandescent temperatures, after long periods without use. And here you thought your oven was for cooking dinner When it comes to doors, you are best off with a hard refractory; even fire brick; for these parts insulation value is a small matter. Mechanical toughness is a major factor.

Well, I see a nice hot forge interior, so you are doing fine. Could you do even matter? Yes, you can always do better...for years, and years. Or, you can just be happy with what you made

thank you again for posting this series of flames someplace where people can benefit from them over time. ...now, k If you can somehow be sweet talked into writing up an account of your burner build, my day will be complete. If anyone disagrees with your choice of design or construction methods, let that flame shut their mouths; it certainly shut mine

In a 3/4" Mikey burner, shortening the mixing tube from nine diameters to eight, will shorten, and harden, a leaf shaped flame into a club. Lengthening the mixing tube up to a maximum of 10" will soften the flame into a smoother laminar flow. How much lengthening or shortening will cause these effects changes by tube diameters. How much is too much? When you don't like the results you've gone to far. Isn't hindsight wonderful?

Mixing tube lengths effect flame shapes the "rule of thumb" on mixing tube lengths, whether eight times the inside diameter ("T" burners), nine diameters (most burners), or fourteen diameters (Vortex burners), are given to achieve sufficient mixing of a burner's gas and air mixture--primarily. By considering these rules of thumb as a ballpark figures, mixing tubes can be lengthened and shotened to effect flame shape. Longer tubes will soften the flame; bringing it closer to laminar flow, which is important for brazing purposes. and as a method to help achieve stability in miniature burners. Shortening the tube will harden the flame, which will shorten it; this can be very important to keep superheated oxygen from creating scale on the work. So, you would most often find yourself shortening the burner's mixing tube to stop scale formation in a forge with very limited space for the flame path; for instance in a short square square shaped forge, with a burner facing directly toward the work. Just remember what the ballpark is for the burner design you are modifying, and change lengths in small increments. It should go without saying that you should not kid yourself about the results you see; if you can't do this, than stay on the beaten path, by following instructions. This technique cannot be used to strengthen a weak flame. You get a strong flame by choosing a burner design known for producing them, and fottowing the designers instructions. You need sufficient potential in the burner's mixture flow, to have something to successfully manipulate. Kidding yourself is no substitute for being in the ballpark before choosing between a fastball and a slider.

I am a notorious picky butt about burners. I practice this not to build a Bentley, but so that when all the things that can go wrong have done their worst, the result will end up satisfactory; that includes the equipment the burner is mounted in. The idea is to start off aiming high, so that you can live with the result. Their have been burners of marginal design that put out marvelous flames, but I would rather not gamble on that; it is a rare exception; not a happy rule..

No; you may be trying trying to reduce my designs to mathematical formulae. but that won't work. In the real world burners have to be made from available parts, if possible. Even if you had the equipment and time to drill your jet orifices using wire gauge drill bits, you would find that there is no straightforward progression of sizes with them. You simply come as close as you can, and live with your results in an imperfect world.

I hope you will give us your impressions of your new forge. One of the questions that many people want anwered is what owners think of the various different brands of commercial forges out there.

thank you. I think ceramics sources that are cooperative, and easy to work with are the very best kind.

Here's another ballpark number for you: the actual WORKING length of the flame nozzle, that is the amount of overhang of a flame nozzle beyond the end of the mixing tube, will usually turn out to be roughly equal to its inside diameter of the nozzle, plus somewhere between 1/16" to 1/8", depending on how large the nozzle is. The rest of the nozzle's length is just used to assure it stays parrallel to the burner's axis.

Thank your for sharing these photos, which show how small changes in a burner can make huge changes in the flame. Folks the shortened club shaped neutral flame, is a fine example of total combustion of a primary flame.

I would sure appreciate those flame pictures, and a write up of the changes you made to get from one to the others, on the Burner 101 thread. Otherwise, they become much harder for people to see at the end of the month, when they will join all the other old files. I want people to see that they don't need a perfect burner design to end up with a great flame. Also they make a fine example of how much, some tweaks in a finished burner can radically change its flame. I can post perfect flames coming out of perfect burners forever, without doing as much good for people who are struggling with tuning problems, as your photos can.

Love the cart! Round kiln tiles make cheap and easy forge doors; it's like they were made for the purpose. BTW, have I mentioned that you are crafting a very nice forge? I'm excited to see how its going to turn out.

Maarten, As a binder for thin hot-face coatings, I don't think there would be any practical difference between Bentone, bentonite, or Veegum; all should work fine for that.

My take on things is along the same lines as Frosty's. Going by Digitalfire.com's materials section, there is a long list of purified Hectorite clay products; all with one kind of advantage or another. However, they are all likely to come with limited availability, just as Veegum, which the author calls the king of binders, does. So, starting with bentonite clay, the purer products will have to be researched area by area, to see how good a plasticizer/binder is available in each. On the other hand, bentonite clay should be available in most places, and will due handily for many purposes; just not for crucible or flame nozzles. I too look forward to what you can come up with locally. No doubt many sources of Veegum and other refined binders will be listed here, as more and more people become interested. But, this subject is going to take people all over the globe, and many years to even make a good beginning at answering these questions.

I am easy to find right here, and I also answer emails. Next step will be looking into Bentone. Yes, what he said about building thermally tough crucibles rocked my world too. It immediately sent my imagination into overdrive about using this stuff as high temperature burner nozzles and muti-port burner heads. In the past, using word searches on the various types of crucibles, had been my main source of PRACTICAL information about refractories; now such searches can be cross referenced on Digitalfire.com. It's been a very good week, thus far

We don't want to forget humble ordinary bentonite clay either. I will be looking into mixtures of bentonite and Perlite for use as lite weight castable secondary insulation, bricks, etc. Waste not; want not