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More stupid questions from a newbie


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Forbidden again.  gonna try an edit.

Hey Frosty.  Could you post T/Nipple/Orifice and your recommended volumes for the burner sizes?

On a side note, Plumbers have some odd jargon.  We had a propane guy come out to install the tank and jets at my Mom and Dad's new place last year and the words the guy chose were priceless when she asked what he was switching out on the dryer.  "Well lady, your orifice is too big."  I guess she had fun with that one.

 
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Nice Frosty. Do you have a pict to go with this? I understand 90% of what you typed, but I tend to be visual, and long texts with no visual references don't often equate well for me. I get the T part, it's the tip/ threaded hookup I'm not 100% sure of.

That's one of the many things I'm editing. Pics are pretty much ready but the text is really wordy like me. I have it ready to gally proof and am sending it to be proof read. It'll be up before too long I hope.

Frosty The Lucky.

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Forbidden again.  gonna try an edit.

Hey Frosty.  Could you post T/Nipple/Orifice and your recommended volumes for the burner sizes?

On a side note, Plumbers have some odd jargon.  We had a propane guy come out to install the tank and jets at my Mom and Dad's new place last year and the words the guy chose were priceless when she asked what he was switching out on the dryer.  "Well lady, your orifice is too big."  I guess she had fun with that one.

 

I LOVE the reactions of non-speakers to jargon.

I think I've posted the burner to forge volume ratios before but the ratio is determined by the sq/in. of the burner tube compared to forge volume. For example a 1" burner will bring 700 cu/in to welding heat. A 3/4" tube is approx 1/2 the area of a 1" tube and will bring a 300-350 cu/in forge to welding temp. A 1/2" tube is again 1/2 the area of a 3/4" tube and will bring 150-175 cu/in to welding temp. These ratios are approximations, some burners just work better than others, all four on my shop forge are a little different. There are other variables besides the "Homemade" factor. Shape of the chamber counts, long and narrow needs more burners of smaller output for an even temp. Forge liner counts a LOT, hard refractory like Missou or hard fire brick is a tremendous heat sink and a poor insulator so a lot of fuel will go to heating the liner. Insulating liners are much more efficient at keeping the heat IN the chamber but are fragile. Less fuel but easy to damage. Kiln washes REALLY help keeping forge liners from being dissolved by welding fluxes while preventing ceramic fibers from visiting our lungs and in some cases increasing the IR reflectivity.

Okay, that's the relation of burner size to furnace volume, you can extrapolate up or down with simple arithmetic.

Jet size can be calculated, I know because guys who can do math better than I have: Ron Reil and Mike Porter for example. Me, I just experimented till I had jets that put the most fuel in the forge and entrained enough air to burn cleanly. My chart says: A 1/2" tube likes a 0.023" mig tip jet. A 3/4" tube likes a 0.035" mig tip jet. A 1" tube likes a 0.045" mig tip jet.

A little basic arithmetic shows the jets follow pretty close to the same curve as the tube cross sectional area. Roughly anyway, scaling up or down it would provide a good departure point to establish the best jet size for your burner size.

Frosty The Lucky.

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Yeah, sorry for asking you for all that again, but I was just trying to consolidate it all in one place, from one source (the horses mouth if you will) until you get your blueprint up, so that people could be directed to this thread until that one gets pinned up (it will be pinned in this forum? that's how things are seeming to work nowadays, and it would be totally appropriate).  My first response was longer and more polite, but you know how it is to be forbidden, probably better than any of us, except maybe Steve, Thomas, Charles, and all the other "senior curmudgeons" who are probably on equal terms in that respect.

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Okay this is what i was trying to post last night when I was forbidden.

How I want to build my frosty T

Okay anyone doubting frosty's knowledge should read his comment that cursing ips dont do much good...... ive been cursing now for 24 hours and i still forbidden!

Edited by cranky
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Okay this is what i was trying to post last night when I was forbidden.

How I want to build my frosty T

Okay anyone doubting frosty's knowledge should read his comment that cursing ips dont do much good...... ive been cursing now for 24 hours and i still forbidden!

Yeah, I actually subscribed to the IPS forum and have tried emailing them directly. The ONLY reaction I get is "All issues have been addressed." IPS has their money and don't care. A perfect example of "don't pay the ferryman till he gets you to the other side."

Frosty The Lucky.

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Lets try again

One thing I have learned from working as a tool maker for a major aerospace manufacture is this.....Anything can and will be over designed and made overly complicated if you allow an engineer to look at it.....This is where I come in.... let me introduce you to my comic book superhero character his name does not exist....I'm more of the villain type, My comic book villain name is "THE COMPLICATOR" able to make the simple to build simple to use simple to own Frosty T difficult to create!

The first thing we are gonna do is acquire our box of goodies, in our box we will find

(1) 1" by 3/4" T this T will have a 1" run and a 3/4" chase (see I do pay attention)

(1) 3/4 by 7" pipe, threaded on one end, both ends, or sans threads if you can cut them yourself (can you all hear Frosty yelling at me? I can " I said 6 inches you idiot not 7, 8 x the diameter of the pipe stupid that's 6" not seven sheesh what an idiot")  I'm gonna put in my ear plugs and pretend I can't hear him for a bit

and finally (1) 1/8 by 3 inch schedule 80 pipe same deal as last time threaded one or both ends or thread one end yourself..... yeah i know this stuff can be a bit hard to get but i have an abundant supply of it thanks to my uncle that worked for a railroad way back when as a pipefitter and managed to find a few odds and ends in his lunch box on occasion. And as my girlfriend, now wife has always said about breasts...."if you got em flaunt em" so go ahead fellows gawk at my pipe all you want 

first we are going to put our 3/4" by 7" (Frosty's face sure gets red when he yells) pipe into our lathe and we are going to cut that pesky weldment from the inside of the pipe, this is a twofold good thing as it will align the OD with the ID and smooth out the ID so there is no turbulence as the air and fuel mixture rush down this pipe.

after this we will install our 1" by 3/4 " T onto our pipe.....make sure you don't take the pipe out of the lathe chuck, we want to keep that perfect alignment. Use a bit of pipe dope (but not the same pipe dope from high school days) and tighten pretty snug.....drill an appropriate hole in the top of the T so you can tap a 3/8 24 thread in the top of T and of course tap the hole..... Now we can remove pipe from lathe.

now we are gonna put the 1/8 inch pipe into our lathe and turn one end down to .375 OD for about 2 inches.....I bet I'm not the only one saying "hey 3/8"... we could thread it 3/8 24"  so lets do that, on the same end we can tap the ID 1/4 24 (or whatever size the mig tip is, I cant remember off the top of my head)

insert mig tip into freshly threaded 1/4 inch hole and tighten, now install a jam nut onto 1/8 pipe and push a rubber washer for sealing on next

now insert 1/8 pipe into 3/8 24 top of T and turn until you have reached an approximate length into the fitting.....tighten jam nut slightly

Okay now this part I have not figured out all the way...Measure from the _________ (please fill in the space) down the pipe 6" and cut pipe. the space could be from the mig tip? (not very repeatable) the bottom of the T? top of the T? suggestions please

thanks for your help and time

Dave

I'm sure I will think of more comments but much too tired right now

For the flairs my plan is to cut a 12 degree angle onto a 1.5 inch heavy tube. heat some 1.25 SS tubing and using a press push my angled tube into the SS pipe....viola we have a good start on a flair....top side of this flair we will make a swage block and run the pipe down though the swage block reducing the Id diameter of the pipe till it slides on and can be held in place by friction fit

these are my plans to try maybe they work.........maybe they won't? wont know till it is tried

 

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Sounds good, but have a couple of notes.  First, at the velocities we are talking about I'm not sure that turbulence inside the mixing chamber is an altogether bad thing.  I see this turbulence serving two functions: first more thoroughly mixing the air and propane, and second potentially reducing the friction effect of the pipe walls to flow (Note that laminar flow is not always your friend as far as friction in piping goes, and no, I'm not going to go through all the calculations to figure the correct Reynolds number to validate this at this point, just going with my gut).  Of course it will probably not be a big deal if you want to bore out the weld seam on the pipe, it could work to make the flow more uniform and symmetrical.  Just seems like added work to me, but would be interesting to have a side by side comparison.

Second, you may find that a threaded fit for the flare is a better idea.  There is going to be a lot of thermal expansion and contraction at that point as you cycle your forge.  A slip fit, like you are suggesting, may not hold up without some kind of further mechanical method of joining.  Typically I try to keep the far end of my flare just inside the first 1/2" or so of the forge insulation, with a small annular step protecting the edge of the flare.

Third, I'll let Frosty make a final decision here, as it is his burner design, but as far as I know it shouldn't make a great deal of difference if the mixing portion of the burner is a bit longer than specified.  There should be a minimum length for adequate mixing and "flow straightening", but I don't see how an extra inch would effect the burner operation unless the induced flow from the ventauri doesn't have enough static pressure to overcome the extra pipe friction in the mixing chamber.

Edited by latticino
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I'm not sure who said it, but one of my favorite engineering quotes is "the sign of a good engineer is the simplicity of his design."

I find this correlates directly with the KISS principal. (For those not familiar "Keep It Simple Stupid")

With both of those being said, I think you're just playing with your abundance of toys by boring out the pipe weld. Black smithing, inherently, is an imprecise precise science. What that means is you use imprecise equipment to make exactly what you/the customer wants. It isn't a precision machine shop where variances are within .003" all the time every time. that's what gives forged items character. Can perfection be achieved? absolutely. But is it always needed? not really.

Also, I see no need for the rubber washer/o-ring on the outside of the T fitting. your fuel air mixture is pulling air into the holes so any air leak at that fitting would just be sucking air into the burner. not leaking out of it.

I too am in the process of building my first T burner, and I think you definitely fit your alter ego with some of the steps you plan on for making yours. Carry on and forge beautiful things.

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once again forbidden

Thor I love the quote has anyone ever met this engineer with the simple design? My favorite engineering quote is " An engineer is the person that walks into a room full of people and immediately knows he is the smartest person in the room" I once had a friend in our engineering department at work tell me I would be a great engineer based on this description......I think it had something to do with my renaming his department "The Herd Of Stupid People" or THOSP as aerospace loves their acronyms.

In my life I wear a number of different hats as a farmer I subscribe to the KISS principle, time is money when something breaks get it fixed fast as possible who cares about form, fit or function, just get back in the field and make some money!

At work form, fit and function are king. I get a overly complicated print to hold some overly complicated part that will repeatedly hold plus or minus .010 results for years to come, this is manufacturing tolerances. Tool Fab (my department) tolerances are 1/10  of factory specs so if a feature has +/- .010 the fixture I make must meet .001 +/- Everything I make at work first goes to Inspection to verify my work, and then goes Io Precision inspection to get double checked and then certified as meeting spec.

So there I was at work, once again grinding down a 4" by 8" by 1" chunk of steel because it was .002 too thick, daydreaming about making a frosty T when I saw a picture of my mustang in my toolbox and thought to myself, If you port and polish the air intake and exhaust of a motor to increase airflow and hence increase power...... why not on a Frosty T. Then my mind just went to town and remembering a comment from Frosty that said, no two burners are the same or something close to that I thought.....Why not?

I agree with the rubber washer O-ring not being needed but this goes back to my car days where sucking lots of air is good.....sucking air from the wrong spot bad.

Today I am at the farm so new rules... It would appear that getting the proper T for a Frosty might be a bit difficult looking online the three big stores Menards, Lowes, and Home Depot don't carry the reducing T needed. looking though my own supply of crap shows none and the three hardware stores in my town don't carry them, my only choice is a plumber shop that has lots of them with a price nearly equal to the number of parts on hand...15 bucks each.... not to worry folks I have them ordered and on the way from www.supplyhouse.com 3.95 each

so now we go full circle....has anyone ever made one of these using a standard T with a reducing bushing? 

Latticino Thanks for pointing out the flaw in my friction fit flare.....gonna have to rethink this one. I was tired, had just gotten off a 13 hour shift at work and driven 3.5 hours to get home (my "job" is 3, 12 hour days friday saturday sunday) and is about 200 miles from my house see I told you I really do live in two worlds

Turbulence might have been the wrong word.... reducing friction and making the flow more uniform and symmetrical was my only thought.... as for Laminar Flow I have never met the guy so will withhold judgement rather he is friend or foe till a later date

I think just for fun I will make a super duper Frosty T, a standard Frosty T as well as a sidearm burner and a super sidearm, hookup an air compressor at 15 pounds of pressure and just measure the amount of air flow from each as a comparison should work? now how to measure without involving a friend that uses a flowbench daily at work?

 

 

 

Edited by cranky
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You bet I get red if I'm yelling but I can't find anything to yell about here. Try harder will ya Dave!

The tube L = 8D is a rule of thumb. 7" will work just fine, now if you wanted to push it to 12" you'd need to engineer in a taper or skin friction would lower induction and you'd need to use a smaller jet to keep up flow.

Boring out the weld bead is a good thing though being a longitudinal obstruction the turbulence it generates doesn't hurt induction significantly and helps mixing. If you're going to bore the tube do NOT use a finishing bit, leave some cutting marks or the flow will be TOO laminar. Propane doesn't mix easily with air, it ACTS like a mist of particles rather than a gas. The good oxy propane torches and air propane burners are designed to induce turbulence in the flow to mix the gasses.

A T using a bushing or bell reducer from 1" > 3/4" makes BAD turbulence and reduces the induction. It can be MADE to work but almost anything can be MADE to work.

If you REALLY want to make a high efficiency T burner use Scd 80 or heavy wall pipe and turn a 12% taper internally and you'll have a commercially efficient burner. Turn a venturi where the weld T meets the tube and start the taper from there and you'll have a proper "Ejector" type inducer.

Early in the current homemade burner phase when Ron Reil Ralph Sproul and a bunch of us old Artmetal List guys were brainstorming these things a coffee shop buddy of mine gave me a stack of literature on the things. Cruze my coffee shop buddy was looking for application patents based on existing devices and I was part of his brain storm group.

Anyway, most of my knowledge of how the things actually work including the 12% max taper rule comes from those papers. While the old Artmetal gang was brainstorming I told them the tube needs to be tapered. Well, Ron installs a taper on the end. I start to do the red faced thing but before I sent the email telling him it won't work I realized the picture of the flame was beautiful so congratulated him instead.

The Side Arm burner came from a similar misunderstanding between me and Robert Groman a caster. I forgot my pad of graph paper and we were on a sight seeing trip down the Arm and stopped for lunch. We were talking about burners and I described my (then) idea for the T burner. A week after he returned home he sent me a picture on his burner. Face went red again and I started telling him he'd put the T on the tube wrong, that won't work but once again fortunately paid attention to the beautiful flame in the picture and congratulated him.

Now I've submitted you to my old memories I'll get on with it. There's nothing wrong with taking your T burner to an Aerospace machine shop if you have one available Dave. If Dad were still around and had his shop That's where I'd build the things. Heck, I ought to get my lathes moved and finish the shop. Stupid TREE! I want to Spin a burner.

The problem with telling folk online how I'd build one to +- 0.001" (Slop for the space program by the way) just puts it out of most folk's ways and means. What I'm trying to make available is something a guy with a hand drill and a few tools can put together and make work. Believe it or not I don't know that many guys with a drill press, even a bench model.

A rubber O-ring anywhere  in the system is a BAD idea unless it's propane rated. I don't use pipe dope either, completely unnecessary if you use tapered pipe and flare or compression fittings and don't over tighten things. If you're not sure check with a little soapy water, I've never had a fitting leak in some 20+ years using these things.

Threading 3/8" OD for the jet mount is how I made my first burner but I just turned 1/2" HR round down and bored it 1/4" to tap for the jet.

The reason I don't even mention this here usually is Most folk don't have a lathe so it's again beyond the ways and means of most folk. In fact I just gave up trying to make this work with hand tools and a 1/8" pipe nipple. I can thread it 7/16" and tap the T to match but a guy would have to make a jam nut so I called it.

Too clunky and sloppy is why I don't talk about using the lamp rod jet mount. It can be MADe to work but was just too much PITA to be worth it.

The real advantage to using a Screw thread jet mount is the precision tunability it offers. You'll need to trim the mig tip jet much shorter to take advantage and be aware too much large threaded rod in the air intake will induce ungood turbulence.

If I were playing with this jet mount I'd use a Cross rather than a T. The machinist's son in me is just dieing to mount up a boring bar and clean up the inside of the Cross where it screws onto the tube. Of course if I were using a weld T or Cross I could turn it before welding it up.

There is a world of ways to make these things work and work well. The T is just easy for a shop with minimal tools and beginner shop skills.

Frosty The Lucky.

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Hey good news guys......I've been thinking again

I think the admins should rename this entire post and make it a sticky for newbies......."THE PROPER WAY TO MAKE A USELESS FORGE" CopyRight Cranky

So here is where I now stand with my great big, forge a lifesize model of the earth, forge..... 

I have a piece of 18 ga stainless steel 9 by 13 inches which I intend to roll into a 11 inch cylinder with a 1/2 inch overlap or so  which I will then pop rivet on the bottom.*with my abundance of toys the thing I am still missing is a TIG welder and I have never welded SS with a mig and not even sure a person can but am assuming it can be done.) We do have TIG at work but we have a very strict rule that any and all government work not being done for the government results in termination of employment ( gov. work is what we codename any and all home projects)

After adding in 2 inches of ceramic fiber insulation I should have have a 7" dia. by 9" long forge body resulting in a fire box that is 346 cubic inches. So according to Frosty's formula for burner size, I am in the top tier of a 3/4 inch T burner..;... easy peasy not so sleazy!  Except inquiring minds need to know some things! this is where my alter ego comes in.

(1) seeing as we are near the larger size limit of a 3/4" burner would it hurt to step up to the 1" burner....other than a bit of wasted fuel usage and back pressure issue which I am assuming could be overcome with a larger opening on the ends? 

(2) Assuming the general answer to #1 is "quit being a cranky and just use a 3/4 " stupid" would it be of any benefit to use (2) 1/2 inch burners located 3 inches from the ends in order to more evenly distribute the heat throughout the chamber?  perhaps shooting one in from each side at an angle

(3) Lets assume the answer to #3 is "Cranky you're a frigging genius why didn't I ever think of that"  Yeah I know I'm pressing my luck with this thought but how bout shooting (3) 1/2 burners in,  1 centered on the length  and one each side 2.25" on center off the first, again from an angle bouncing the flame off the opposite wall, once again in order to more evenly distribute the heat and also improve the needs of heat from being at the larger end of a 3/4" allowance?

(4) Quit being a cranky and just use a 3/4" burner stupid

 

Second part of my question

Instead of a cylindrical forge body would it behoove me to flatten down my forge allowing for a bit more floor space and possible wider working area, you know in case I ever decide to forge a battle axe intended to slay dragons with, just for more clarification if needed make a oval forge versus a round one

So now I will await your answer's while I enjoy my lunch......one slice of pecan pie and one slice of apple pie with a big glass of milk to wash it all down....... no advice needed on this....

Thanks

The Humbled Dave

I also have to correct my statement about the availability of reducing T's.... I was at menards last night and bought a 1x3/4 T which they DID have on hand and a 6 inch 3/4 pipe both of which were proudly made in china and cost a tad bit more than the ones I ordered from supplyhouse.com and about the same if shipping is taken into account

hey i had one more idea last night...... what you all think about going high tech and making Magnesium burner flares Cool huh?

 

Edited by cranky
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Yeah, sorry for asking you for all that again, but I was just trying to consolidate it all in one place, from one source (the horses mouth if you will) until you get your blueprint up, so that people could be directed to this thread until that one gets pinned up (it will be pinned in this forum? that's how things are seeming to work nowadays, and it would be totally appropriate).  My first response was longer and more polite, but you know how it is to be forbidden, probably better than any of us, except maybe Steve, Thomas, Charles, and all the other "senior curmudgeons" who are probably on equal terms in that respect.

hot digity I just got promoted!

crusty I may be but I have a long way to go before I reach there level of skill, much less crotchetiness!!   

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Charles may I be the first to tip my hat to you on your promotion..... i know I'm new here put I think you were promoted quite some time back and everyone failed to tell you

I like you, your pretty gosh darn alright in my book and plenty crotchetiness as far as I am concerned may I suggest a bit of salve and a tad bit less time in the saddle sir?

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An isue that can develop is that the flame needs a given length in wich to consume the fuel before it hits an obstacle, and alowing the heated jet to swirl around the curved walls apears to provide a more even distrabution of heat. 

Some articles I have read suggest that a 12" tube, with 2" of insulation works well, and that the 1" burner is more effecent in converting gas to heat. 9" is the size of a firebrick. 

My self I am thinking a 12" arch over a flat floor with two firebricks making a 9" square flore. My Pro Forge is a fuel hog unless you need to heat 16" peices of 2" round... 

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You are joking regarding the magnesium burner flares, right?  Might want to check the flash point on magnesium first.  Even though the flare is cooled by the combustion mixture going through it while running there is always a chance you might shut off your burner while the forge is still at elevated temperature.  Since it is naturally aspirated that forge temperature will certainly heat up the flare.

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edit

Yes my bad 9 X 36 not 13...too many numbers in my head

so charles your reply gives me another question. is there an advantage using lighter walled material for the shell over heavy walled other than weight?

so how about 12" Id pipe bottom cut off with some flat plate welded in to give me 9 inch square floor 2 inches of insulation and two firebricks put on top?

this would all be 3/8 steel

actually would I even need insulation under the hard firebrick if the forge was sitting on nonflammable stand? this could prevent flux from eating the insulation, on other hand it would also make for easy repair when needed due to flux melt

Edited by cranky
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