Burners 101

[Mikey98118]

Aligning pipe fittings to mixing tubes

Most burner designs are considered easier to make with threaded plumbing parts; that can be true, or far from it; depending on the quality of those parts. Cheap imported fittings are becoming the rule as steel water pipe is marginalized by copper and plastic. Cheap pipe fittings are often made from marred castings, which don't thread properly, producing axially misaligned threading in the finish part; such parts make misaligned burners, which cannot be properly tuned, and thus produce poor flames. Here are some answers to this problem:

 

(1) Avoid buying threaded fittings from large generic hardware stores. They don't have a good selection of fittings, and tend to use cheap imported stock. Look for regular plumbing supply stores or HVAC supply stores, instead.

(2) Hand screw fitting and pipes together, and inspect them before purchase; crooked fittings are easily spotted this way. Don’t stop with screwing the reducer to the smaller pipe that will be used as its mixing tube; add a larger pipe on its large opening and revolve the assembly in your hands. Whether the parts are axially true or not quickly becomes apparent.

(3) If you must buy your fittings online, consider using stainless steel instead of cast iron; stainless parts are likely to be much higher quality.

(4) In the end, the surest answer to a problem, is to avoid it. Every threaded pipe fitting has a much higher quality butt-weld equivalent. Pipe can be used in the next smaller size to the fitting's opening, slid into position (after a little power  sanding, or filing if it is oversize), and held in place with socket-head setscrews.

    This is a little more work than screwing together threaded fittings, but gives much better part control, and superior flow. Don’t forget to grind an internal bevel on the end of the pipe that slides into the reducer fitting.

[Mikey98118]

Using Air/fuel torches as mini burners

Note: the self-igniting option on air/fuel torches doesn't usually work very long; its piezo eclectic crystal is durable, but the spark wire portion of the unit can fail in short order. What happens is that for a split second during ignition there is some blast force generated on the wire’s end; this gradually moves the wire enough to prevent the spark from jumping the gap between wire and the torch body (which provides its ground). You can push the wire back into position two or three times, and then it breaks off.

    There are a large variety of air/fuel torches, new and old, that can be remade into  equipment burners. Recently, I have been seeing MAP gas hand torches marketed online (AKA dual-use torches) that are rated to burn propylene as well as propane); some of them feature a stainless steel mixing tube, with makes them fit for use as equipment burners, with the addition of a doubling tube to prevent them being oxidized away.

    Some air/fuel torches now come with a short fuel hose, instead of just being mounted on a 16 oz. cylinder. Separating the torch from its fuel cylinder allows it to be easily positioned at any angle, while the cylinder, which must remain upright, can do so unhindered; but its value when mounted on a forge or casting furnace is that the fuel cylinder can then be kept a few feet away from the hot equipment.

    The latest versions of air/fuel torches also feature two needle valves. One valve is part of the cylinder fitting, while the other valve is mounted on the torch head. You may wonder why two valves? The answer is safety. With a separate valve at the fuel cylinder, the hose and torch can be exhausted of positive pressure after shutdown, while a second valve on the torch can then be closed, preventing ambient air from mingling with fuel gas in the hose.

    Without positive pressure, even a needle valve is unlikely to leak, while pure fuel in the gas hose is no more flammable than pure air is. We might think that simply detaching the assembly from the fuel cylinder will do the same job, but the reason that 1 lb. fuel cylinders are not supposed to be refilled is that, once opened, their valves are no longer reliable; they can leak.

    The whole point of discussing air/fuel torches is that they can be used, with some modification, as a practical substitute for 1/4" burners, which can be built, but would cost more than these torches, to do the same job; that job would be running two-brick and coffee-can forges; at less than $30 they are a bargain.

 

Note: there are fuel hoses of different lengths available, which have various fittings on their ends; some of them have female fittings on one end to connect with a fuel/air torch and a male fitting, with a needle valve included, on the other end to attach to a fuel cylinder; these allow you to use the torch of your choice to do the same jobs cylinder mount torches.

 

    “Flame tubes” are one of the various names manufacturers hang on the combination mixing tube and tip that their air/fuel torches use as flame retention nozzles. I have seen double, and even triple flame tubes on air/fuel torches; so long as their flame tubes are stainless steel, they should work okay inside miniature forges and casting furnaces, for a while. But, even when their flame tubes are made from stainless steel, things "are no slam dunk." My torch has a single stainless steel flame tube, which has an internal fin for helping to mix the fuel air mixture; that appears to also be stainless steel, but it might have been made of brass in a cheaper torch; this would have made it undesirable as an equipment burner.

    A double or triple flame tube isn't going to be easy to mount in a burner portal opening. More than one flame tube is going to be hard or even impossible to slip a doubling tube onto. My burner's flame tube wall is only about .030" thick. When mounted in a forge or casting furnace, the super heated portion even stainless steel tubing will oxidize away. Without a thick walled doubling tube, that torch wouldn't last very long. Also a doubling tube allows us to use thumbscrews in the burner portal’s tube to securely hold the torch in place. What it boils down to is that just because we can get away with a thing (for a while),  doesn't necessarily mean we should try to.

 

 

The STK-9 air/fuel torch: I choose this air/fuel torch, not because it will make the cheapest or hottest burner to build, but because it allows the easiest miniature burner to constructed, and is a reliable model. Aside from fitting a thicker doubling tube over its flame tube, all other parts are purchased with the torch, until you construct a forge or casting furnace and mount the torch in it.

    Building miniature burners from scratch are only fun for diehard enthusiasts. Furthermore, once you get down to a 1/4” homemade burner size, reasonably priced propane torches can more than match their output for less money that you would spend on building materials to construct a burner from scratch. So, for use as air/fuel hand torches, building such burners are largely a waste of time.

    Until recently, canister-mount air/fuel torches didn’t get mini forges and casting furnaces hot enough to be a practical choice; the problem was that their brass flame tubes had to remain outside the equipment’s burner portal, to keep from being melted; this led to excessive secondary air being inducted into the equipment by the flame,  interfering with proper heating.

    Stainless steel tubes have been appearing on some air/fuel torches in recent years, so that they would able to also burn propylene fuel safely (since the Canadian plant was switched over to it in 2008, all so called MAPP fuel has actually consisted of propylene since then).     

    A stainless steel tube also allows, “dual fuel” torches to heat miniature forges and casting furnaces (coffee-can size and smaller) efficiently, through mounting in a burner portal exactly like commercial and homemade propane burners; this also holds true for “two brick” miniature forges.

[RToons]

On 3/11/2019 at 6:53 PM, Mikey98118 said:

.025" MIG contact tips are perfect for some 3/4"  burners

A Tweco (or Tweco style in another brand) 14T 0.025” wire size MIG contact tip has a 0.034” orifice that is as close to perfect for a 3/4” high flow speed burner as parts ever get; Tweco style 14T tips are 1-1/2” long and tapered. The threads on this series of tips are 1/4-27 (their taps are available in welding stores, and online); however, they will probably be plug taps, and you want to use a starting tap (AKA tapered tap) when threading into mild or stainless steel, to ensure that you don’t break off the tap in a hole; this will ruin your day. A MIG contact tip, being soft copper, can be threaded into a standard 1/4-28 threaded hole, if it is carefully screwed into place the first time; thereafter it will screw in easily.

I have the .025 or 0.6mm Wire Contract Tip or the MIG .025 tip.  I drilled a 1/4 hole and placed threads to ensure I had the correct size. Well they fell through? Driving me crazy! When you suggest a 1/4-28 tread count that seems incorrect or I am going nuts here attempting to tap for these tips to screw in?  Any ideas!

[Frosty]

3 minutes ago, RToons said:

I have the .025 or 0.6mm Wire Contract Tip or the MIG .025 tip.  I drilled a 1/4 hole and placed threads to ensure I had the correct size. Well they fell through? Driving me crazy! When you suggest a 1/4-28 tread count that seems incorrect or I am going nuts here attempting to tap for these tips to screw in?  Any ideas!

You don't know how to tap threads is the problem, not the tools nor instructions. 1/4" hole is not the correct pilot hole to tap 1/4" x 27 or 28. 

Download and print a chart for taps and dies so you can refer to it in the shop. This is as basic a shop skill as using a hack saw or file.

I'm not going to try conducting a metal shop 00.1 class online. I'm not trying to discourage you but this is too basic a question to ask from someone attempting to build a forge and burner. Please do some reading and maybe take a shop class. College extension classes aren't too expensive for the knowledge and practical, marketable, skills offered.

Frosty The Lucky.

[Mikey98118]

Thands for saving me the effort, Frosty. I deleted my answer when yours appeared. 

[Buzzkill]

22 minutes ago, RToons said:

When you suggest a 1/4-28 tread count that seems incorrect or I am going nuts here attempting to tap for these tips to screw in?  Any ideas!

You can probably find a set which contains both the tap and the correct drill bit size for that tap in the same package.  I've never used any, but there are also combination drill bits/taps available.

[RToons]

3 minutes ago, Frosty said:

You don't know how to tap threads is the problem, not the tools nor instructions. 1/4" hole is not the correct pilot hole to tap 1/4" x 27 or 28. 

Download and print a chart for taps and dies so you can refer to it in the shop. This is as basic a shop skill as using a hack saw or file.

I'm not going to try conducting a metal shop 00.1 class online. I'm not trying to discourage you but this is too basic a question to ask from someone attempting to build a forge and burner. Please do some reading and maybe take a shop class. College extension classes aren't too expensive for the knowledge and practical, marketable, skills offered.

Frosty The Lucky.

Very mean reply Frosty! True I do not know how to tap threads! As a mechanic, burner, welder, Field Artillery Gunnery Sergeant, IT professional and 60+yrs of life I NEVER had reason to utilize a tap other then STANDARD dolly leg screws. Suggesting this is to simple of a question for anyone building a forge lacks consideration and respect for individuals!  I guess many can tap like crazy but ask to weld tie downs on trailers, work on a maxi-break without getting their head taken off, Lay in a Howitzer as safety NCO or change a tire and they stare into the deep. Not impressed with your understanding that if tap skill lack they do  NOT belong anywhere near a forge!!!  

25 minutes ago, Mikey98118 said:

Thands for saving me the effort, Frosty. I deleted my answer when yours appeared. 

Sorry you delete your GOD like standing in TAP eternal knowledge! A good thing to be all knowing on all forging topics leaving you above ANY question you feel is to basic! 

[Mikey98118]

I understand you're feeling heated, but I haven't taken a poke at you, so why not calm down and continue your quest?

[RToons]

40 minutes ago, Frosty said:

You don't know how to tap threads is the problem, not the tools nor instructions. 1/4" hole is not the correct pilot hole to tap 1/4" x 27 or 28. 

Download and print a chart for taps and dies so you can refer to it in the shop. This is as basic a shop skill as using a hack saw or file.

I'm not going to try conducting a metal shop 00.1 class online. I'm not trying to discourage you but this is too basic a question to ask from someone attempting to build a forge and burner. Please do some reading and maybe take a shop class. College extension classes aren't too expensive for the knowledge and practical, marketable, skills offered.

Frosty The Lucky.

Without your intension to assist me I did take NOTE of the suggestion to look at a TAP & DIE chart.  This chart answered the basic question I had and was better they just a reply on what size to use!  Thank You in any case!

[Frosty]

Thank you for serving.

If you can't take a straight answer feel free to block me. I'll not bother you again if I can help it.

 

 

[ThomasPowers]

Wow; I've been smithing 38 years now and when I need to tap something I go get my metalshop text book and read up on it as I know it's not one of my basic skills.  I suggest to my students that they keep an eye open for such a text for their own use. I think I paid US$1 for mine.   I also have a copy of Machinerys Handbook to look up machine tool feeds & speeds.   I know I lost a bunch of info my last couple of concussions and at 60+ myself I don't know how much I will get back.  I tend to go to my books first and post questions when they don't provide me the info needed.

Note that they do make inserts if you have already over-drilled a hole and need to make it smaller.  I can usually buy *1* off my local mechanic.

Being told to hit the books is a compliment---means they think you can learn from reading up on it.  Not everyone can.  (Remember the 3 types of people and the electric fence?)

[Mikey98118]

While there is a lull in the fighting, are there any other questions? I promise not to get peppery (having had my Valerian)

[ThomasPowers]

Valerian Steel---best for spoons and other non-weaponized items...

[Mikey98118]

Don't feel bad Thomas. I check my thread figures on an online tap& drill chart constantly.

[RToons]

4 minutes ago, Mikey98118 said:

While there is a lull in the fighting, are there any other questions? I promise not to get peppery (having had my Valerian)

You are a man after my own heart!  I did download the TAP & DIE chart as suggested by Frosty and it more then answered my question. Your reference advise is appreciated and I should have done some looking before I submitted that question!  I blame my laziness on the RA meds. Lol!

[ThomasPowers]

I hopefully haven't picked up RA yet---but my endocrinologist tells me that once you have one autoimmune issue you may go on to collect the whole set over time and I already have Diabetes and Hypothyroidism and probably a few others in development.   I can't retire anytime soon as I have to maintain my health insurance.  Hurting does make one peevish in my experience; not to mention the side effects. (I love those ones which mention DEATH as a possible side effect!) I had an insulin crash earlier this week and a convulsion---luckily I made it to my bed before I blacked out.   

[SLAG]

Thomas,

OUCH!

I hope that you are feeling better, now.

SLAG.

p.s.  Also you,  Mikey 98118,  hang in there.

[RToons]

11 minutes ago, ThomasPowers said:

I hopefully haven't picked up RA yet---but my endocrinologist tells me that once you have one autoimmune issue you may go on to collect the whole set over time and I already have Diabetes and Hypothyroidism and probably a few others in development.   I can't retire anytime soon as I have to maintain my health insurance.  Hurting does make one peevish in my experience; not to mention the side effects. (I love those ones which mention DEATH as a possible side effect!) I had an insulin crash earlier this week and a convulsion---luckily I made it to my bed before I blacked out.   

I was forced to accept LTD from my employer[I did purchase LTD benefits so with my wife working & me getting 66% of salary we are OK for now]. My better half is constantly telling me I am deaf, cannot see straight[I have MD which bends everything making reading very hard], cannot walk straight & have dementia; but she has always encouraged me to burn myself, smash my fingers & just push myself as not to become lazy!  So after 37 yrs of her I will do as she says and build a forge for pain & suffering. 

The DEATH and serious reactions warning is on every med I take and on just about every pill, IV, injection or inhaling med produced! I appreciate your understanding of the crazies in this world!

[Mikey98118]

I'm still getting over the aftereffects of a diabetic coma last week. No way I could handle this if I were still holding down a job! Hang in there, Thomas.

[ThomasPowers]

I'm holding down a job that entails crossing the border twice a day---the people here at the factory can't understand why I have to work.  The crash is only painful if you hit something---like my two bounce tests of my skull vs concrete.  Now the convulsions leave me feeling like I've be thoroughly kicked all over.  But I tell folks; if I wake up---I'm going to recover. No hospital trip needed.  If I don't wake up No hospital trip needed neither...  Now I did have to be tested for epilepsy to get my driving privileges back.  Interesting test; not much fun but interesting. Wired up with 52 leads at the max and then asked to not sleep for 4-5 days.

Anyway keeping my insulin pump away from the Dragon's Breath  helps a lot and I go out of my way to use my larger hacksaw as an exercise program.

[RToons]

Just now, Mikey98118 said:

I'm still getting over the aftereffects of a diabetic coma last week. No way I could handle this if I were still holding down a job! Hang in there, Thomas.

I agree. How can anyone be in the public working with such a serious condition? Or have to work to keep medical benefits! I lucked out but once I hit 65 it will all end and the dog food is the chow of the week and meds must end! We have been fighting with the state & fed for benefits for my mother-in-law but given she worked her entire life and now getting social security she is NOT eligible for mediCADE that pays ALL medical & medicine bills!  Crazy system that if you worked & get SS , which does NOT cover much,  you can live in distress with medical issues but if one never worked or not eligible for mediCARE you can get mediCADE and get all the medical and meds FREE?  

What type of work do you do Thomas?

[ThomasPowers]

Software Engineer.  Having worked on a number of international projects I've been exposed to a number of other systems of health care, (European, South American, English, etc)  I find I tend to overreact when I'm told that American's don't want mandatory health care coverage or coverage for preexisting conditions. Oh well; about time to head north for today!

All y'all be safe and remember "You Hold the Cold End and Hit the Hot End---and get it right next time!"

[Frosty]

Uh. . . If it's okay with you guys can we pretend this was just old farts with: TBI, stroke, etc. issues having a synchronized low blood sugar cranky coots episode? 

The part I didn't say well regarding cutting threads as being a basic skill is. You ALWAYS look up the correct pilot drill and or tap before cutting threads. My tap and die sets have the charts imprinted in the plastic cases. Yeah, sets I have SAE and Metric tap and die sets. My better drill indexes also have tap charts imprinted in them. I have a machinery's handbook in a top box and a machinist's text book up stairs. 

I keep the pilot bits and taps for making T burners in a cigar box with the necessary fittings so I don't have to remember or look anything up.

If you're not cheating you're not trying and I try to be as trying as possible.  

I'll try to be cool. Okay?

Frosty The Lucky.

 

 

[Mikey98118]

16 minutes ago, Frosty said:

You ALWAYS look up the correct pilot drill and or tap before cutting threads.

Especially when tapping stainless steel. There's nothing that can beat a broken tap trapped in your almost finished burner to give you a really bad day

[SLAG]

Frosty,

May I suggest that the  pilot bits and taps each be partially embedded in individual wine corks.

The size can then be written on the body of the cork, and the bits will not bang around and become dull.

SLAG.