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Burners 101


Mikey98118

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Gotcha. I wonder if the same effect can be achieved by parting off the small end of a bell reducer, choosing the position of the cut to select the depth of the bullnose. Might have to try it when my lathe shows up.

Edit: When you say a mil, does that mean (since it's a 20% reduction in the outlet) that it's for a 5mm ID mixing tube?

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I will do so, Mark.

Twigg ,
I only mean to describe their general shape. But, yes, the commercial versions of flame tube do have a thicker cross section of wall thickness at the end orifice; I assume this is from spinning them into shape; whether the thick edge is also used for deliberate advantage or not, I don't know.

Let us not forget the probable use of refractories in making some of these heating tips.

Are you reading this, AFB?

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Mark,

Just read your letter on the other computer, but it isn't on this one (the wife bought me a laptop, so I'd keep her company in her garden room :-)

So, while I/m trying to deal with it fully, my best advice about essential books for a guy like you (or me) is:

Metalwork & Enamelling by Herbert Maryon. It was the inspiration behind my own poor text. No, they have nothing in common contextually, but his utter honesty was the shinning goal before me during the 2-1/2" I wrote away on Gas Burners for Forges, Furnaces, & Kilns. It would take another decade of writing to match the amount of useful information in his.  BTW, don't change the spelling of the title; it's English (not American), and so is the publisher.

That should have read "2-12 years"; obviously the burner instruction writing in the present text is starting to get to me :rolleyes:

Do you want to build a 3/8" canister mount burner?

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Making miniature gas jets from capillary tube & MIG contact tips

Miniature burners (3/8” and smaller) bring up an instance where friction of the moving gas molecules down their tiny jet orifices become a major design factor. In larger burners, the smaller the gas orifice diameter the leaner a given size of burner tends to burn, in even the longest available threaded MIG contact tip. But, due to increased friction, you will find cutting a 0.020” I.D. capillary tube 9/16” long and mounting it within a MIG contact tip (drilled to match the capillary tube’s outer diameter, if necessary) will make a hotter output flame than a longer capillary tube, in these orifice diameters. Then, sanding the trapped tube down to a finish length in the MIG tip of .406” (13/32”) long with 0.020” I.D. capillary tube (or a little longer for 0.023” I.D. tube) will gain the best result from this part.

    Torch tip cleaners are made from a harder stainless-steel alloy than capillary tubes, but it isn’t so much harder that they can be successfully used to enlarge orifice sizes in stainless steel tube; but they are perfect for getting rid of internal burrs, so that the holes where the gas inters and exits the tube can be made round; a lighted magnifying glass is recommended to help elderly eyes check that all burrs or gone.

    For building a gas jet from miniature tubing (thick wall capillary or thin wall hypodermic) and a MIG contact tip, I recommend using a (Tweco style) Tweco, Miller, Lincoln, or Radnor (1-1/2” long tip, with 1/4-27 thread). If you can get a tapered tip, that’s good; otherwise, you will have to spin it in a drill under a file or sandpaper, to taper it yourself.

    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, even if they’re available. 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. Chances are that the shipping charge will amount to less than the gas you may waste receiving a rotten experience, while trying to buy them locally.

    Radnor and Tweco Model 14T-052 (1-1/2” long) MIG contact tips have an approximately 0.064” orifice size. Depending on tolerances, 1/16” (outside diameter) heavy wall capillary tube will fit the orifice loosely or tight, but the work of mounting it won’t be much either way; these tips are available from amazon.com and eBay, and through online welding supply sites.

    Stainless steel 1/16” tube can vary from .060” to .065” outside diameters, depending on the manufacturer, and MIG tip tolerances can vary by up to .003”. So, you may end up with an interference fit that requires little effort to mount. Or you may need to swage the MIG tip down around the capillary tube, or else silver braze the tube into the MIG tip, or you could even need to drill the MIG tip hole a little larger.

    Heavy wall brass or even copper capillary tubing, normally employed as electronic discharge machining (EDM) tubes, can also be used as gas orifices. Even thin wall stainless steel hypodermic tubing can be used, so long as both its inside and outside diameters are listed; it is available as dispenser needles, and as 3’ to 5’ lengths. MIG contact tips come in limited orifice diameters, as do capillary, hypodermic, and EDM tubing. You must begin your search for a convenient tube with the desired orifice size (inside diameter). Next, you try to find a MIG tip with as close a match to its outside diameter as you can. Saturn Industries, Inc. has been a practical source of EDM tube in the past.

    Typically, a dispenser needle with an inside diameter of 0.020” will fit into a .023” MIG contact tip. MIG tips are designated by welding wire size. The actual inside diameter of such a tip is between 0.031” and 0.033”. If it turns out a little undersized, a wire file from a torch tip cleaners kit will adjust the tip opening in its soft copper easily.     

    If a MIG tip’s diameter is within .005” oversize to the tube, it is easily swaged down to trap heavy wall tube in it; with a tapered MIG tip, you may be able to create a fit by running tape around its tapered end, and squeezing plyers around the thin tapered section.

    With a plain (none-tapered) MIG tip, even thin wall tubing can be swaged into the MIG tip, but you have to drill a 1/4” diameter hole into two 1/4” x 1/2” or wider 1” long mild steel flat bars; clamp them hard together in a vice, and drill a 0.246” hole (with a size “D” drill bit) completely through the bar, and then clean off all burrs. Power sand the open edges of each half- hole a few thousandths of an inch, so that a ¼” O.D. MIG tip will drop freely into the drilled-out troughs, but can be swaged down, compressing the MIG tip tightly around the capillary tube.

    Slide the desired length of capillary tube into the MIG tip, and place it within your new swaging die; Tap the top bar with a hammer. Cut off the excess tube to within a 1/8” beyond the tip’s end, and hand sand it back to within 1/16” of the MIG tip’s face. Then clean out any internal burrs, with torch tip cleaners. Final shortening is done during tuning.

    If the MIG tip’s orifice is only a little too small for the capillary tube. You can use torch tip cleaners to enlarge it a few thousandths of an inch. You will find one of the wire files in the set to be small enough to push back and forth within the MIG tip, while turning the tip slowly. You need to frequently check the enlarging hole against the capillary tube, during filing.

    Wire gauge drill bits can be hand spun in a pin vice to enlarge holes in MIG tips to within a couple of thousandths of an inch of your capillary tube; keeping the hand filing (with torch tip cleaners) from becoming tedious. It is easiest to only increase the size of the orifice a couple thousandths of an inch at a time, when filing copper.

    Don’t depend on your eyes for guidance, when drilling in copper. Pay close attention to the amount of tension felt in your fingers. Start drilling by barely touching the end of the tip’s hole. Stop frequently to clean burrs and dust out of the drill bit, and blow them out of the MIG tip, from the hole’s other end. When you feel a sudden increase in tension on your drill bit, reverse its direction until the hidden inner burr in the hole is knocked loose, before continuing.

    Drill from the front end of the tip to 1/2” deep. If you don’t have a miniature drill press and drill vise ($$$), your hole is going to end up slightly oversize at its opening, and will taper down smaller as it gets deeper. You should be able to push up to a 1/2” long length of hypodermic or capillary tube into it with just enough interference to trap it in place with the help of a few light taps on the tube.

    Ink mark the tube at 9/16”. Cut the capillary tube 1/16” beyond the ink mark. Tap the tube into the MIG tip, and screw the tip into place on the gas pipe. Tap the whole assembly against a metal surface, or (ex. one of the pipe parts), until it comes within 1/8” of the MIG tip’s front face.

    Use a circular motion on a sheet of very fine wet/dry sandpaper (#400 grit) to reduce it down to within 1/16” of the tip’s face; use the torch tip cleaners to remove the tube’s internal burr. During tuning, try the burner to see if it has a satisfactory flame; keep sanding the tube a few thousandths shorter at a time, until it does.

    It is important for the outside of MIG contact tips (in small burners) to be tapered for proper flow of incoming air, as it passes by the gas orifice, on its way from air intakes into the mixing tube. How important? How small is your burner? The smaller the burner the more important it becomes. On a 3/8” burner it is fairly important, and will matter ever more as you build ever smaller burners.

    Although capillary tube can be made to serve as proper gas jets in small burners by varying their lengths to match output velocities of different gas orifice diameters, lengths and diameters will remain a matter of trial and error, because of tolerances; plus or minus .001" of an inch is a lot of difference when the orifice is between .020" and .023”..                                                                                                                                                                                            

  Remember, the mounted capillary tube should be closely inspected under a lighted magnifying glass to make sure all burrs are completely eliminated from the tube’s orifice; it needs to be completely round; not jagged. Otherwise, the gas stream won’t be smooth.

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Thanks Mikey!

Sorry to drag the conversation back to heating tips, but I just want to make sure I follow. Narrower, longer flames are faster (higher flame velocity), correct? Assuming every other aspect of the burner is equal

Haven't forgotten about castable refractory. Just prototyping and playing around for now

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On 3/7/2021 at 1:14 PM, Mikey98118 said:

Are my fellow Frankenstein types listening?

I caught this one but I didn't want to presume it was directed at me.  I am indeed reading this.  

I am still tinkering with nozzles.  Currently, I am playing with FAM velocity at the ejection point to see its effect on flame propagation velocity and forge temperature.

I have not played with the bull nose shape.  I have a dual fuel bernzomatic torch which employs one but it also has a baffle to cause what they call a swirl flame.  As far as I can see, the baffle causes the FAM to rotate and slings it to the outside wall of the nozzle which then hits the bull nose, I think to prevent it from continuing to sling outward.  

I have one of my burners as a hand torch but it has a standard nozzle on it.  I have not thought about nozzles specific to hand torch use.

 

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I have quite a collection of various propane and dual fuel torch-heads; all but one of them purchased in recent years, irregardless of flame tube design, contains the internal swirl device. The single exception has a pattern similar to butane blue-flame lighters (radically different then the rest of the pack).

It is possible that the bull nose tip shape merely serves as a similar purpose to oxyacetylene welding tips: in  part to create a high pressure area at the end of the tip to discourage burn-back into it.

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4 hours ago, twigg said:

but I just want to make sure I follow. Narrower, longer flames are faster (higher flame velocity), correct? Assuming every other aspect of the burner is equal

More often than not; but not absolutely, with air/fuel equipment. Mainly, we are after longer narrower flames for more targeted heating. In brazing, as well as torch welding, the flame heat is used to control filler bead formation by capillary attraction. Intensely hot tiny impingement points equal fine weld bead control :rolleyes:

This means little for silver brazing, or soldering work. But braze welding, is the goal.f I am gradually sneaking up on low cost braze welding as a practical technique for newbies :D

Twenty years ago my very best burners were able to, just barely, braze weld pipe parts together. Now, I'm making canister mount torch-head burners. Now there are propylene fuel canisters available in hardware stores, which should increase flame heat about 600 more degrees in air-fuel burners. Now, there are oxygen generators sold for about $250 to get another 300 degrees through oxygen enrichment. All this means I can reach oxy-propane torch temperatures, and braze weld INEXPENSIVELY--and teach others to do so too!!! Am I there yet? Almost; just need to come up with some welding tips.

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On 3/4/2021 at 10:20 AM, Quitemanforge said:

thank you all for the information and the tips on the photos..

i will get some sharper ones put up when i get back to the house  thanks again everyone

hi all I was gonna put pics up but me and the computer are having a slight disagreement so guess its me trying to paint ya,ll a picture lol,

ok so i got the burner pipe moved and lengthened a bit so that's good now I'm just going around noticing places I'm losing heat from ah yes the fun continues.. or as Walter Sorrels says turd polishing lol 

have a good day all!! hammer on 

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1 hour ago, Quitemanforge said:

or as Walter Sorrels says turd polishing lol 

Speak of the devil. This is half of a set of polished dinosaur coprolite book ends. Nice polish eh? :)

Frosty The Lucky.

1981813000_Coprolite02.jpg.c4cf99b706f3c6a525b1a92be5848b9d.jpg

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Save your pics to a folder on your computer. You can resize them there by doing a "Save As" to a smaller file size. I just tag the original file name with 01-02, etc. Some pics I make a few different size files.

I attach a pic or other file by selecting the Choose File link at the bottom of the text window.  There's a choice, the paper clip drags files to attach, I have no experience using it though. I use what I'm familiar with.

Select "choose files" and locate the file you wish to attach in your computer and double click it. It will appear below the text window as a thumbnail with a + in one top corner and a trash can in the other. The file will be placed in your post where the curser is blinking WHEN you select the + button.

They usually appear in the text window way over large size wise. Double click on the pic and a window will open with resizing, rotation, line position, etc. options. Select maintain ratio button and the pixel count can be adjusted.

For example the pic is 800 x 625 and takes up the whole page select the 800 window and change it to say 400, the other aspect will automatically change accordingly when you select the update button below.  

You can't make the pic larger again if you over smallafied it. so double click and press the delete button and start over. At any time you select the trash can button the pic and thumbnail is gone. You'll have to start fro your computer files if you didn't mean to do that. Ask me how I know, I dare you I'll laugh at you though.:P

I'm sure I've gotten a couple details wrong, I'm not loading a pic while I type. That's the general method, it won't take much experimenting to figure out. It's a lot simpler than my description. 

Frosty The Lucky.

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On 3/8/2021 at 2:27 PM, Mikey98118 said:

Do you want to build a 3/8" canister mount burner?

That sounds right in the wheelhouse. Thank you! Sorry you’ve worn out all your computers writing this great stuff ...but as a beneficiary it’s very appreciated! :D

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On 3/7/2021 at 4:58 PM, twigg said:

Edit: When you say a mil, does that mean (since it's a 20% reduction in the outlet) that it's for a 5mm ID mixing tube?

Like most of my generation, I totally rejected various new math, or new anything else that "those stinking teachers"  tried to fob off on students back in the sixties; that included millimeters, etc. Years later I discovered that they were useful for quickly calculating equal picket distances in gates, where measuring in inches was a pain. Since I'm involved with imported tooling, in order to help novices construct heating equipment without "breaking the bank", millimeters are back in my life :P

But no, I wouldn't consider pet names for them; Even if I were so inclined, the need for clarity would stop me cold.

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10 hours ago, MarcBaldwin said:

Sorry you’ve worn out all your computers writing this great stuff

No; just a keyboard on this old computer. The Dell laptop om the other room has a funky operating system. Kathy has ordered a replacement for it from a different OEM. I will never touch another Dell piece of JUNK!!!

 

did you see the general instructions for building gas orifices for 3/8" burners I posted in Burners 101? They are straight out of my 3/8" burner chapter in the new book. Go ahead and start your burner by building the gas orifice, while I review the other twenty pages of instructions. When complete, I will email the whole chapter to you. This is the burner I posted a photo of last year in Burners 101.

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14 hours ago, Frosty said:

Save your pics to a folder on your computer. You can resize them there by doing a "Save As" to a smaller file size. I just tag the original file name with 01-02, etc. Some pics I make a few different size files.

ah ok thank you!

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On 3/7/2021 at 5:58 PM, twigg said:

Edit: When you say a mil, does that mean

I'm not sure how it's being used above because of the metric/standard fun but a mil in standard machinist terms is a "thou" or thousandth of an inch (0.001").  

This is needed because in standard, the smallest measurement we use is an inch before going to fractions.  Counting in tens is just smarter so when tiny measurements are needed in standard, mils are used.  I was raised on standard.  Now I use both because I have to.  How much I prefer subtract 1 or 0.1 or even 0.01 over multiply the numerator and denominator by 2 or 4 or 8 depending on how small the size change needed, subtract one from the numerator, and check for common denominator to determine the next size down.  The most annoying part is working on anything that uses both systems.  Second being needing to have two sets of tools which are almost identical but aren't. 

I'm done :lol:

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Imagine how annoying it is for us here in the Netherlands. Some companies makes 99% of their bolts and parts with a metric system. And then one little bolt is in Imperial. Had this happen so many times when I was working with hydraulic systems. All the nuts are metric, and the little hex screw is in Imperial. all you can do is bust out a file and just make yourself a new tool.

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Didn't want to write a chapter explaining the Engineer scale ruler? Just pick your scale, It's WAY easier than trying to teach someone to read vernier calipers. If you like freedom of scale try maps from areal photographs. There were times I used pins and vernier calipers to establish a scale for the prints. I still have my multi scale drafting traveler. 

Fun times and I never thought Dad insisting that as long as I lived at home I'd stay in school and take drafting every stinking semester would pay off! Yeah, 14 semesters of drafting, it got so I was helping the teacher, especially the two college drafting 101 classes I had to take. <shudder> I don't know what his regular subject was but it certainly was NOT drafting. That's the first place I saw a drafting arm, we didn't have one on our tables but there was one on the chalk board. 

I tell you, coming from T square, rule and triangles background the drafting arm was instantly understandable. I didn't get to use drafting software until I bought my own and the computer to run it.

Unfortunately what I can find is all 3D rendering software and is frankly useless for building stuff. I really don't want to have to save my allowance and BUY a copy and wade through all the bells and whistles Bull to get to the useful parts. <sigh>

Ah, Dr. Frankenburner and I have been typing at the same time. I am SO glad I didn't do architectural drafting! WHEW!

Frosty The Lucky.

 

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I had two semesters, of drafting in the senior year of high school, and then forgot all about it. Eight years later it served me well at Todd Shipyards, and from then on until retirement. Never drew a blueprint since 1964, but had to read hundreds of them in the shipyards :)

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I followed your recommendation and it was just too weird for my poor dented brain. It also made a mess of my computer memory, it wouldn't just save in the drawings folder, it used it's own seemingly random digit file system. That seems to be pretty common for programmers to want their software to appear first on any system it's loaded into.

If that were all it'd be easy to adapt to my system but my comp's operating system puts things where it wants regardless of what I want. 

I know it's mostly a Me problem but I have the brain the TBI left me. <sigh>

Reading blue prints was the reason Dad always gave for insisting I take drafting. It's come in handy my whole life. Being able to read a print has gotten me a number of jobs. I've been chalking that one up for Dad for a long time.

Frosty The Lucky.

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