Burners 101

[Mikey98118]

On 10/27/2020 at 6:19 PM, Another FrankenBurner said:

Both the forge and the burner are older designs.  I am currently working on updating the 1/4" burner for a forge this size.  I still haven't built a micro(nano?) forge for the 1/8" burner yet.  

I have been meaning to ask that you post a how-to that discusses the main points of your forge build; it would make a nice contribution to your own thread; I wish to see it kept active, and become permanent on IFI. To keep it active you have provide interesting contributions (salt the mine), until it becomes a point of interest. Newer designs are always a worthy goal. However, people will not wait for them; they want to build NOW.

[Mikey98118]

Air openings and other changes in small repurposed torch-head burners

It is fairly easy to add a thicker stainless steel tube snugly over the very thin (0.035" typically) stainless steel flame tube of an air/propane torch mount burner; this will protect the flame tube's thin wall from vanishing from high heat oxidation for a considerable time, if no performance improvements are sought.

Eventually the end of the flame tube will oxidize away. At this point the flame will become destabilized, and the torch-head must be replaced, or upgraded. "In for a penny in for a pound" time start then. You can either spend your money buying a new torch head, or spend no more, and perhaps a less, upgrading your torch-head into a proper equipment burner.

The first step: is to add a spacer ring around the doubling tube's forward end, and then add a third tube. around the spacer ring; this is your new flame retention nozzle. What sizes? Try for something approaching 1/16" to 1/8" thick wall on both new tubes; these become your minimums and maximums. But what about length? The amount of overhang needed for a flame retention nozzle to work properly is equal the the diameter of the flame tube, plus 1/8" extra to allow you to adjust the flame's hardness by pushing the nozzle back and forth on the flame tube. To this measurement add whatever length you found convenient in the spacer ring's length.

Second step: A flame retention nozzle is going to try to induce more air into the burner, and so you will probably need to improve the old torch-head's air openings; if they are just holes in the flame tube,  a drill little larger bit inserted into each hole, and then turned at an angle leaning toward the flame tubes rear, should do the trick. If the air openings are in a thicker walled brass fitting, do use the same method. If the air openings air oval shaped, use a small drill bit to to create the desired bevels in it rear and forward edges, without creating any appreciable changes in their sides.

Step three: If your torch-head is left on full cylinder pressure, chances are that its gas jet will need little or no modification; in that case, use nothing more than torch tip cleaners to enlarge it. If you enlarge the gas orifice too much, than you will have to add an adapter hose, regulator, and POL refillable fuel cylinder to the burner, to get it back under control.

[Mikey98118]

If no one thinks they have questions on this subject, perhaps Frosty will at least debate some points with me to raise reasonable doubt? I know there are people who are using cylinder mount propane torches in micro forges. You would be better served to ask questions before your torch starts deteriorating. or it goes through a lot of fuel canisters, needlessly.

[Mikey98118]

Flame king Dual 1-pound Propane Cartridge Carrier with female P.O.L. outlet ($36.12); this device securely holds two one- pound propane canisters, screwed into two male QCC inlets (for throwaway canisters), which are part of a gas manifold that ends with an external POL inlet; this works exactly the same way as the main valve on a refillable propane cylinder. The whole unit is contained in a hard-plastic carrier; including handle. At last, a legal way to transport propane in your car; not to mention legally store and use it inside your garage.

    Flame King also has refillable (D.O.T. compliant) 1-pound propane canisters ($19), along with a D.O.T. compliant refill system; available on their website.

[Steve Sells]

Safety discussion on Power tools has been split off and relocated to the safety section

[Frosty]

So long as we can go on about what terrifying carnivorous monsters rotary tools can be, anytime the subject comes up, we're okay with the move, Steve. 

Frosty The Lucky. (to have all his fingers, eyes and such.)

[Mikey98118]

I'm not not okay with the move, Frosty

[Frosty]

You weren't talking about safety other than as part of normal operation of rotary tools. I'm sure Steve will move yours back if you ask. 

Then again you were getting away from building burners and more into operating and evaluating rotary tools. Thinking about it maybe you've drifted far enough for a rotary tool section of it's own. You were posting identical posts in two sections too. Maybe if you brought it back to building burners.

Now I just don't know, Brother. 

Frosty The Lucky.

[Mikey98118]

You know, all that sound reasonable. Just a little late coming after the fact, and from the wrong person.

[Frosty]

Ah, it's easier to be objective from the outside. 

It's never too late and there is no wrong person for pointing out reasonable. 

Iforge is a fluid place that self corrects, things will settle out and adjust. 

Frosty The Lucky.

[Glenn]

68 posts were moved into its own thread "Power tools"  in the safety section so it would be easier to find in a dedicated discussion.

[Irondragon Forge ClayWorks]

Along with the duplicate posts are still in Forges 101, which is a good place for them also.

Good move with the Power Tools thread, that way other forum users who never look at the Gas Forge section will benefit from it.

[G-son]

This thread is a gold mine of burner designing & building information. The upside to that is that the information you need is very likely in it, the downside is that just like a gold mine if you are looking for one specific thing you are going to spend hours looking through material you may not have a use for. 

It's great, but as a single forum thread can't really be divided into chapters and sections like a book it's impossible to make the information structured and easy to find, you WILL have to read it from start to finish, and probably more than once to absorb the information. 
An in depth discussion about power tools is probably great too, but it doesn't really fit well under the topic of how burners work and are designed, so I support the decision to move it to a better place. As I said, Burners 101 is a gold mine, but it doesn't make sense to add more rocks to it to make it harder to find the gold - even if that rock happens to be top quality marble it won't do you much good when marble isn't what you are looking for.

[Mikey98118]

S0, abandoning the how-to, and back to the what and why to...

Why Reducers

It is necessary for incoming air to sufficiently mix with fuel gas. A swirling motion provides the most mixing for the least interference with flow. Pipe reducer fittings is a convenient ready-made form for this purpose.

It has been well established that the gas pipe and whatever MIG contact tip, etc. is used for a gas orifice should be axially centered in the reducer's large opening by, whatever means is convenient.

BUT, "the devil is in the details," because how you choose to mount the gas assembly, is your first and best chance, to gain that something extra that we all want in the flame; don't waste it!

Why such emphases on a minor detail? You have an energy budget; it's limited to the air induction that your gas orifice supplies to the gas stream, which is that burner's main air engine. It takes energy to get air moving, and energy to change air motion. So. starting that change of direction at the same point that  that the motion begins, will require the least energy from your tiny budget.

So why not install a big old high powered fan; compressor; atomic bomb;etc. at the opening?

How much breath is required to blow out a candle? That is about the maximum power input--at the wrong place--it takes to blow out a burner flame too. You want burner magic? It comes from CONTROL.

Another important factor to consider; as with a whirl pool, all of the incoming air motion is going to be near the periphery. Little to no air will move down the center of the opening, So what? So this should tell you where streamlining matters, and where it  doesn't.

[Welshj]

On 11/28/2020 at 2:46 AM, Mikey98118 said:

I'm not not okay with the move, Frosty

I'll take the blame there Mikey- as it was my suggestion to do so. So I apologize. Steve merely agreed and followed up on that request.

As I stated when I suggested it, there was alot of merit in that twist of the thread. Between the excellent, more technical information you posted... (I learned a few things I didn't know about tools ive used for decades) and our battle scar stories... I thought it should probably not be buried in a thread that was relatively off topic to that part of the discussion.

It was/is important info- and should be easier to find.

I still have yet to make it entirely through this thread!

[Mikey98118]

It's past. On with the new.

[Mikey98118]

So, mounting a gas assembly has two facets; what is easy versus what is best. There can be no "perfect answer to fit all," because, aside from tooling and skill levels, we all have our "druthers." I would 'druther' have maximum control of the parts being put together. Someone else will prefer one method of assembly over another. It all depends.

But, starting from the desired end, and moving backward toward a necessary beginning point, let's start with a flat sheet metal disc (yeah, year, some of you are already changing that out for a flat washer; good on ya mate). Cut the disc large enough to completely cover the reducer's lip, or just large enough to fit snugly within the opening, depending on whether you want to tack-weld,  silver braze, solder, glue, or screw it in position.

[Mikey98118]

Cut a hole in the middle of the disc for your gas pipe, or threaded gas tube to slide through. Mark out three roughly equal spaces for ribs between the air openings. You need nothing more than a hex nut to show you where. Drill 1/4"  or smaller holes between the areas of the ribs and  well outside the area of the nut,  Remember that there is no air flow in the part of the opening, so don't shortchange yourself on material in this area.

So, the ribs would be fairly narrow if you kept their line parallel, but that isn't desirable. You want them to become wider as the extend toward the periphery of your disc. You will either bend them downward at an angle (one-quarter inch is plenty), if you kept the disc small enough to fit inside the opening, or you will  cut part way through their ends, and bend most of the width downward, leaving part of it still connected to the outside of the disc, Why would you bother? To ensure that everything remains in a flat plane. Thus, helping to ensure that the gas assembly will remain axially true to the burner. Once again, what you do will depend on how you like to proceed toward the goal.

[Mikey98118]

What kind of nut? That would be a nut for 1/8-27 NPS, better known as lamp thread. What is a 1/8” IP thread? 1/8” IP or IPS (iron pipe, or iron pipe standard) thread dies and taps can be used to make lamp rod thread (1/8-27) on the outside of 1/8” water pipe (designated size; actual outside diameter of 1/8” pipe is .405”). This is parallel thread, and is not to be confused with the tapered 1/8” NPT (national pipe thread--which is tapered); this is used on the ends of pipe nipples to mount your gas fitting or needle valve to. This means that your gas jet can be easily installed on your burner, with a flat washer for a choke included. Be sure to use an "S" letter drill bit; not an "R" bit, which is recommended for tapered thread; not parallel thread.

    1/8” schedule #80 pipe can be directly threaded with ¼-27 (best) or ¼-28 (acceptable if you’re careful) taps, to accept a MIG contact tip.

    For people who can’t find or afford “doing things the right way,” or find all these parts and tools, there are brass pipe, steel tube, etc. that can be slid into lamp thread from your hardware store, where it can be trapped in place with silver braze, solder, or even resin; it’s the lamp thread that has to move back and forth, for proper tuning. A nut snugged up on either face of the hole in the sheet metal can keep everything tight, so there is no need for tricky solder or brazing work.

    Finally, no you don’t need to match up the inside of whatever you use for a gas pipe with the inside of the lamp part. Adding inner and/ or outer spacers are just fine so long as you solder, braze, or, glue them, to prevent movement between your parts. Inner spacers don’t even need to be gas tight; just the ends of the gas tube need that. Inner spacers are just there to improve flow. 

[Mikey98118]

Circumstances always alters cases. Lamp thread is too large for use in micro-burners. Fortunately, the same mounting scheme can be carried out by threading brass tubing; thus allowing ever smaller parts to be installed in ever smaller burners.

MIG contact tips can be replaced with refrigeration tubing and needles as gas orifices.

[Mikey98118]

Gluing gas assembly parts?

Anyone who has played around with oxy-fuel or air-fuel torch parts will have noticed that a few of them are glued together with some kind of black resinous substance. And anyone who has rebuilt an engine knows that gasket sealant is black and quite tough. Two and two makes…

    Thread sealant comes in hardening and non-hardening types; both kinds are resistant to vibration, and, like gasket sealant, thread sealant for fuel lines, are rated for use with petroleum products.

LPG stands for liquid petroleum gas; that includes propane, butane, methane, and propylene fuel gases.

[Frosty]

You got my attention with that one Mike. I THINK the goop is sealant rather than glue.

I could be wrong I admit, I don't see the inside of many commercial burners or torches so I don't actually KNOW. I have stripped my All States oxy propane rig down pretty far and it's all precision ground connecting surfaces, no sealants. There are a couple plastic components away from the torch head where things flex or twist. I'm not counting the O rings on the tank fittings and hose connections, they're not really the subject.

If there's a glue being used in burners I'd bet it's a phenolic resin, the higher temp formulations can take high red heat without breaking down. Neat stuff, expensive but neat.

Frosty The Lucky. 

[Deimos]

something like loctite?

[Mikey98118]

Frosty,

I used the term "gluing" as an attention  grabbing device, which isn't factually wrong, if pushing the point somewhat. But, yes, I agree that it is properly called  sealant, as that is its primary purpose; but, not its only use; it is equally important to keep the parts trapped in place; thus it is gluing them together. I strongly suspect what the product is, but "don't actually know" either, but I think it is gasket sealant

Deimos,

I believe some Loctite products would work well enough for this proposed use. Would I use them on oxy-fuel torches? No; just about everything on a torch has to be done in an approved manner, with approved materials, and in some states, by certified people.

[Deimos]

I thought as much, only ever used Loctite for bolts and bearings. Hated it when people used it for hydraulics. I take it oxy fuel torches keep pretty cool right?