# How to repair radiant gas poker burners, plus improving your burner by installing a radiant "tent"...



## clifforddward (Jan 2, 2008)

*How to repair radiant gas poker burners, plus improving your burner by installing a radiant "tent"...*

Several folks have asked for information about repairing the wire mesh radiant "tents" on gas burner tubes, as well as adding this radiant feature to burners that did not have it originally. Below are photos from my recent repair to the gas burner on my Mike Chaney Climax. This great running little engine has been our "go to" locomotive for running not only at hobbyist steam-ups, but also runs at our local garden railroad group meetings....it has had many hundreds of hours of run time, perhaps as much as 1000 hours before the gas burner finally gave up the ghost and performance started suffering. The pictures tell the story, but what happened was the 304 stainless steel inner mesh finally corroded to the point that it literally fell apart. This caused the burner to start acting erratically. This is to be considered a natural event, the result of many hours of run time. Like a light bulb, things like this on our live steamers will need to be renewed from time to time.








Like so many projects with our engines, just getting to the part needing repair is more than half the battle...here it took me nearly a half hour just to take the rear half of the Climax apart to get to the gas burner so I could pull it out of the boiler. Lots of loose tiny screws, so use tubs and be careful with everything!









OK, so here you can see the culprit...the 304 stainless inner mesh is completely burned up...as I disassembled the unit the mesh fell apart in my hands...time to fix this!









Here you can see the sheet of 304 stainless steel (100 mesh) that I'll be using to make a new replacement...this mesh for both the inner and Inconel outer mesh is available in a variety of wire gauges as well as mesh sizes. It is an industrial product, available typically with minimum buys. The minimum purchase I made gave me several lifetimes of the stuff, so I have some available (details below) for any others that may want to do repairs to their burners or experiment with using a radiant tent to help improve a gas poker burner that does not already use a radiant tent. Please note when experimenting you'll need to test the burner in the boiler tube itself, as the burn characteristics are different when these burners are in open air as compared to burning inside the intended tube. Experiments in the actual boiler are best.









Pieces cut and formed by simply pressing around the tube of the burner...the inner mesh wraps tightly around the gas tube....be sure to make the outer burner with enough of a "V" to leave some space between it and the inner burner...it is the outer mesh that will become radiant and glow red during operation.









Here's the finished assembly, using inconel wire to hold everything together...the wire goes through the outer mesh to help hold everything in place.

So that's it!....an hour re-assembling the locomotive and she fires up good as new...I expect many more hours of run time before I'll need to do this repair again.

For those who may not want to acquire inconel and ss mesh to do this repair yourself, I can offer a service to install new inner and outer mesh to your burner at a price of $25 including return postage in USA (International slightly higher to cover extra shipping costs). Interested persons can contact me at: [email protected]

Best Regards and Happy Steaming...






Cliff Ward
Cary, North Carolina
USA


Here are the details of the "kits" of mesh I have available:
-One 8" x 8" piece of Inconel mesh 40 x 40 screen size (for outer "tent" around burner)
-One 8" x 8" piece of Inconel mesh 30 x 30 screen size (for outer "tent" around burner)
-One 8" x 8" piece of 316 Stainless Steel 100 x 100 screen size (for inner wrap around burner)
-Approx 6 feet nichrome wire (.025" diameter) for holding above screens on burner
Should be enough material to repair a handful of burners.


I have a couple of kits to above specifications, plus another 2 kits with two pieces 4" x 8" of each type instead of one 8" x 8" piece...same square inches of screen, just two pieces instead of one for each screen type.

Available first come, first served, priced at $50 each plus shipping for the 8' x 8" screen kits, and $45 each plus shipping for the kits with 4" x 8" screen. 

I can ship one or more kits in a USPS small flat rate box within USA for $5.15. International shipping at cost...examples for UK or Australia using the same USPS small flat rate box is $16.95.

Payment via PayPal.

Interested persons please contact me offline....


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## roadranger (Jan 6, 2008)

*RE: How to repair radiant gas poker burners, plus improving your burner by installing a radiant "tent"...*

Cliff- How does the screens improve the burner? More heat? Does it cut down on burner roar? 

Also, I can see how the outer screen would work to radiate more heat, but what is the purpose of the inner fine mesh screen? 

Finally, should the outer screen actually touch the boiler tube at installation, or is a space required between screen and tube? 

Thanks for any info!


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## clifforddward (Jan 2, 2008)

*RE: How to repair radiant gas poker burners, plus improving your burner by installing a radiant "tent"...*

Hi Jim:

I can only provide a theory as to the exact purpose of the inner mesh...as you can see from my Catatonk Climax example, it was the inner mesh that was worn out and needed to be replaced. Before repair the burner had become difficult to light, erratic burning, and quick to blow out on a regular basis. Immediately upon replacement with new inner mesh excellent burning characteristics returned. I believe that the inner mesh helps to spread out the gas/air mixture and provide an even surface for the actual ignition to take place...the outer mesh then burns in a radiant fashion. I do not think it would be possible for the outer mesh to obtain a radiant burn without the inner mesh.

I have not experimented a great deal with radiant burners...just repaired a few. I can say that for the ones I have installed there is a "tent" space between the inner mesh and outer mesh, formed by pinching the outer mesh in a slight inverted "V" shape. In my examples, at least, there also is an air space between the outer mesh and the wall of the burner tube. I can also say that the burner absolutely burns differently in open air than it does in the tube, so any experiments will need to be done with the burner in the tube in order to be of any value.

There is an article in the reference section of "Southern Steam Trains" web site that discusses radiant poker burners in some length...a read of that article would provide a good starting point for anybody wanting to investigate this matter more fully: http://www.southernsteamtrains.com/...urners.htm


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## Pauli (Jan 3, 2008)

*RE: How to repair radiant gas poker burners, plus improving your burner by installing a radiant "tent"...*

Hello Cliff,


I don't know if this is a matter of US versus European ways to express measurements, but I would like to get an idea of what the inner mesh should be like. You talk abot "304 mesh" initially, and you are offering "316". In the Southern Steamtrans link, the inner mesh is described as "40 or 50 denier". 


Looking at offerings in Sweden, none of the above measurements are used. Denier is not really used for anything but genuine textile cloth and fibre, but reading Wikipedia I get the impression "40-50 denier" would be wire strands like 0,4-0,5mm, wich sounds very thick to me. Looking at the pictures, I get the feeling the inner mesh steel cloth is almost like something in between a bed-linnen and semi transparent textile curtain-sunshade in density. And I would guess wire strands are more like 0,25mm?!?


Also, The tecspecs I find give a percentage of coverage / "let through". With a wirethickness of about 0,25mm, "let through" ranges 50-60%.


For the outer mesh, you write it's number 20, wich I interpret as 20 strands per inch, wich would be squares of 1,27mm, minus wire thickness. However, this outer mesh I guess isn't really that critical dimension wise, I would guess?!? 


A year ago, I picked up am IKEA kitchen utensile for something like two bucks. It's somekind of round mesh-lid for boiling-pans. I haven't gotten around to installing it yet, and my hope was that it would stabilize burner behaviour, especially with a cold boiler. Knowlidge of this practice around me is rather anecdotic hearsay, so reading your describtion and at Southern Steamtrains is very interesting!


Im hoping some supplier of SS mesh-cloth might give me a small sample piece, possibly for free :-D I read this kind of material is also used for screen-printing (of cirquit boards?). Have you heard? Is that possibly suitable?


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## lotsasteam (Jan 3, 2008)

*RE: How to repair radiant gas poker burners, plus improving your burner by installing a radiant "tent"...*

Free scraps(may bee a couple bucks) you'll get from an printshop who do screenprinting! They have all sorts of wirescreen available! 

Manfred


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## jfrank (Jan 2, 2008)

*RE: How to repair radiant gas poker burners, plus improving your burner by installing a radiant "tent"...*

Posted By Pauli on 18 Oct 2012 06:21 AM 
Hello Cliff,


I don't know if this is a matter of US versus European ways to express measurements, but I would like to get an idea of what the inner mesh should be like. You talk abot "304 mesh" initially, and you are offering "316". In the Southern Steamtrans link, the inner mesh is described as "40 or 50 denier". 


Looking at offerings in Sweden, none of the above measurements are used. Denier is not really used for anything but genuine textile cloth and fibre, but reading Wikipedia I get the impression "40-50 denier" would be wire strands like 0,4-0,5mm, wich sounds very thick to me. Looking at the pictures, I get the feeling the inner mesh steel cloth is almost like something in between a bed-linnen and semi transparent textile curtain-sunshade in density. And I would guess wire strands are more like 0,25mm?!?


Also, The tecspecs I find give a percentage of coverage / "let through". With a wirethickness of about 0,25mm, "let through" ranges 50-60%.


For the outer mesh, you write it's number 20, wich I interpret as 20 strands per inch, wich would be squares of 1,27mm, minus wire thickness. However, this outer mesh I guess isn't really that critical dimension wise, I would guess?!? 


A year ago, I picked up am IKEA kitchen utensile for something like two bucks. It's somekind of round mesh-lid for boiling-pans. I haven't gotten around to installing it yet, and my hope was that it would stabilize burner behaviour, especially with a cold boiler. Knowlidge of this practice around me is rather anecdotic hearsay, so reading your describtion and at Southern Steamtrains is very interesting!


Im hoping some supplier of SS mesh-cloth might give me a small sample piece, possibly for free :-D I read this kind of material is also used for screen-printing (of cirquit boards?). Have you heard? Is that possibly suitable?

The stainless steel mesh is available from McMaster-Carr. They give all the demensions including the 40x40 and 100x100 sizes.
http://www.mcmaster.com/#wire-cloth/=jrvvuh


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## clifforddward (Jan 2, 2008)

*RE: How to repair radiant gas poker burners, plus improving your burner by installing a radiant "tent"...*

Hello Pauli:

Sorry for any confusion...the terms 304 SS and 316 SS refer to the type of Stainless steel in the mesh.

The terms 40 x 40 Screen size and 100 x 100 screen size refer to the wires per inch in the mesh....the actual coverage is dictated by the gauge of the wire...I opted for the finest wire for a given mesh size in order to have a more open mesh.

John is right, the stainless steel mesh is readily available from a variety of sources....but best used only for the inner mesh....in a radiant burning application like the outer mesh it will not hold up nearly as long as the Inconel material. The reason for the different mesh sizes is that experience has shown there are some differences in how different burners glow within the burner tube of a boiler...experiementation will be needed.

Hope this helps clarify.

Best Regards,
Cliff


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## Pauli (Jan 3, 2008)

*RE: How to repair radiant gas poker burners, plus improving your burner by installing a radiant "tent"...*

Hello Cliff and everyone,

What about mounting the fine inner mesh inside the poker burner, rather than wrapping it around? Or is that not possible? (Maybe because the poker burner usually is soldered together?) At least at first glance, this seems like an obvious and elegant way of mounting the finer inner gas distributing mesh. (I'm assuming gas distribution can be agreed upon as the purpose?!)

Less than ideal, the 100 mesh I was given for free yesterday, is actually from bronze material. The owner of a local mechanical manufacturer had been building prototype machinery for papermills and print industry, and laughingly, with a forklift lifted down a storage box containing mesh of varying qualities, while stating "it's always good to save the really odd scraps". I tend to agree with his reasoning, that the inner mesh is not in the flame, and only serves to distribute the gas, so the bronze could work. At lest for a while... and since he gave me enough material for at least 10 burners, I'll try it out. 

Just blowing through the mesh by mouth, it has no discerneable resistance to air/ "gas"-flow.

The finest stainless steel mesh he gave me, is roughly half as fine. Should I go with that right away? Do you think the bronze will burn away instantly? Thing is, althogh my original motive was to get a better behaving, less "unresty" burner, and getting rid of the burner roaring sound that I mind, I'll now also add the outer tent ss mesh to make a radiant burner. Even though I really don't need to improve efficiency to conserve gasconsumption. I have one warm and one extra cold extra gastank in the tender, wich easily allows me to refuel during runs, if needed.

With a glowing outer radiating tent mesh, the inner mesh is likely subjected to very strong heat, not usually found "under" a flame. Maybee this precludes the bronze material?

Well, I'll let you know how things progress.


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## clifforddward (Jan 2, 2008)

*RE: How to repair radiant gas poker burners, plus improving your burner by installing a radiant "tent"...*

Hello Pauli:
Thanks for the update...glad to hear you are going to experiment with the materials you were able to obtain for free, that is what this hobby should be all about. I've never heard of bronze mesh being used, and logic would say it may not hold up like Stainless Steel, but the price was right and one never knows until the actual experiment is done....I applaud your efforts and look forward to the results...keep us informed as to your progress!


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## jackcon (Jan 27, 2012)

*RE: How to repair radiant gas poker burners, plus improving your burner by installing a radiant "tent"...*

Stainless Steel will hold up as burner mesh screens - but not forever. 

Bronze Mesh - forget about it - will not last a year 

The best thing you can do is look for some high heat material, something like an inconel wire mesh - seen here - http://www.bwire.com/index.html 

This stuff will last a lifetime. This is what the big burner companies ex: Coleman, have been using for years. Pricier than stainless steel obviously, but will withstand the test of time. 

PS - 304 and 316 are NOT the same thing - in Europe or the US, the difference is the amount of nickel that can be found in the alloy.


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## clifforddward (Jan 2, 2008)

*RE: How to repair radiant gas poker burners, plus improving your burner by installing a radiant "tent"...*

Yep, you are correct...Inconel is the way to go...that's why I made the minimum purchase and had the extra to make the offering below in the first message of this thread. 

Best to use Inconel for the outer mesh that glows radiant...316 stainless steel seems to hold up fine for the inner mesh... 

I still have a couple of kits available if anyone has a need...

Best Regards,
Cliff


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## jackcon (Jan 27, 2012)

*RE: How to repair radiant gas poker burners, plus improving your burner by installing a radiant "tent"...*

How much was the minimum purchase? If you dont mind me asking! $100?


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