Small Gas Poker Burner

[Tony Bird]

Hi Gus,

Sorry I cannot help withyour glow plug problems.

Please advise silver solder rod content. I use higher silver content for ease of brazing. Air conditioners' silver solder rod can be tough to melt and run. Plan to buy a double torch Mapp Gas Torch after watching demo.

At the moment I am using Easyflo No.2 silver solder and flux which melts at about 640C. Sorry I don't know how this compares with solders used in the USA. The pickle I use is Citric acid which I get from Home Brew/Wine stores. The powder is mixed in hot water until the mix is saturated. I.e. when crystals that won't desolve appear in the mix. I use a plumbers gas torch with interchangable heads fed from a large bottle of Propane. I always use a torch head that is too large so the job heats up quickly.

Your silver brazing looks good and the pickling good too. Very professional.Mine tends to run all over.

Solder will run over any part of the job that has flux on it so paint the flux on carefully where you want the solder. Warm the joint slowly so the water content of the flux mixture evaporates rather than boils and runs all over the place. Hope this helps.

Regards Tony.

 

[Tony Bird]

Hello again,

Plugs for several burners have been made, I hope the photographs convey how they were made.

Regards Tony.

 

[gus]

Plan to make same boiler.Have plans from from old issue ME magazine.

Plan to buy the twin torch MappGass Burner. Will need two burners from experience gained from past boiler projects.Living
in a low rise flat and locked up in small balcony space limits my expansion plans to go into bigger projects.

Copper pipe bought years ago but need to make end cap former.

 

[Tony Bird]

Hi,

Yesterday made a sleeve to fit into the plug to hold the poker. The sleeve is made from a 9/32" K&S brass tube with a piece of 1/4" K&T brass tube inside it as a stop for the poker. The 1/42 tube is made a little too long to form a shoulder that works as a guide for the soldering, this shoulder is turned off after soldering. The 1/4" tube is slightly deformed using a 3 jaw chuck so it is a friction fit in the larger tube. Doing this shops the smaller tube moving into the larger tube while soldering. The sleeves made were then soldered into the plug making sure that they are fitted the right way around with the soldered tube on the outside!

More to come.

Regards Tony.

 

[Tony Bird]

Hello again,

Having a bit of a problem with Photobucket so doing it in sections.

With such a small burner commercial gas jets as supplied are too large so have to be altered. If a threaded bush has been fitted in the sleeve they can be made to screw in as on my test rig. Or as in the case of the sleeves made a slide fit. The test rig one is screwed for safety as during tests it would be easy to pull out. Most of my burner jets fitted to models are a slide fit it makes them easier to take out if a jet blocks, thay are held in place by copper pipes not silicon tube as used on the test rig. Photograph shows a jet as bought and altered to either a screw or a slide fit.

Regards Tony.

 

[Tony Bird]

Hi,

To finish describing what was completed yesterday.

Creating the air hole in the sleeve, the soldered brass is very soft so it has to be carefully done. First a round file was used across the sleeve to create a flat section for the drill. A round not flat file is used as it is easier to get the flat in the correct place also it is easier to lightly centre 'pop'. A small drill (2mm) was used to create the two air holes. The holes were increased is size by either using a round file or a tappered broach, I used both. The raised ridge created by opening the holes both inside and outside of the sleeve were removed with a fine file, this helps smooth the air flow into the burner. The photographs show the effect of increasing the size of the air holes from the 2mm drill hole to 4.3mm when the gas/air mix is OK. The burner was then checked working inverted in the boiler and then with a smaller poker fitted. This pug will now be capable of supplying the correst gas/air mix to most burners that can be fitted into it.

Five more to do today!


Regards Tony.

 

[Tony Bird]

Hi,

Unless there are any questions it looks like it is the end of this thread. Today finished the six plugs and fitted some of them with pokers and put them in the three boilers that are finished.

I now have to make the rest of the fittings for the boilers. Goodall water top-up valves have already been made and fitted so it is safety valves, water gauges, regulators and save up for some pressure gauges.

Hope you enjoyed the thread.

regards Tony.

 

[Tony Bird]

Hi,

Very short video of the control of the burner fitted with short 2 hole poker.



Regards Tony.

 

[metal]

Hi Tony,

Thanks for the very useful pictures. Once I'll get a lathe again I'll certainly use them!

Some remarks: at the first (?) page you refrain from the use of cross tubes because of turbulence, however heat transport improves with turbulence. I would advise to make the crosstubes out of solid in order to have enough wall thickness and choose the steam pickup point carefully (avoid too wet steam).
Further: when I'm making a flue with cross tubes I do the hydraulic test on the flue only first, so I'm sure it is sound before soldering it in the boiler (which is necessary with my solder skills ).

Further I was wondering if you are aware of the concept of a radiant poker burner, as can be seen here: http://www.southernsteamtrains.com/notes/radiantpokerburners.htm. These burners seem to be more efficient compared to the default blue flame poker burners.

Cheers,

 

[Tony Bird]

Hi,

Some remarks: at the first (?) page you refrain from the use of cross tubes because of turbulence, however heat transport improves with turbulence. I would advise to make the crosstubes out of solid in order to have enough wall thickness and choose the steam pickup point carefully (avoid too wet steam).

I'm sorry I didn't make myself clear. I didn't use cross tubes as they would have had a very small hole through them about 1.6mm (1/16"ish) apprantly according to the late Colin Binnie these small tubes would work like 'pop-pop' engines and create a lot of turbulence. I haven't prooved this myself but it seems logical. Certainly convection currents in a boiler are a good thing but not too much turbulence. When steam is released from a boiler there is a certain amount of turbulence in the area of collection hence steam domes or perforated pipes fitted to the top of the inside of the boiler. The boilers described have their regulators on the top because of no steam dome being fitted.

Further: when I'm making a flue with cross tubes I do the hydraulic test on the flue only first, so I'm sure it is sound before soldering it in the boiler (which is necessary with my solder skills

).

I usually do the same but I don't have a rig for such a small tube and as it might well have been a one off, I relied on a good visual check. As a horizonal boiler using a 15mm flue tube is being made some plugs will be made so that the flue can be pressurised from its inside.


Further I was wondering if you are aware of the concept of a radiant poker burner, as can be seen here: http://www.southernsteamtrains.com/notes/radiantpokerburners.htm. These burners seem to be more efficient compared to the default blue flame poker burners.

Yes they are but I don't know of a design that will work in a tube with an ID of 13.5mm. If there is such a design I would be very interested in it. Photograph shows a radient burner designed to fit under a pot boiler.

Last evening the boiler fitted with cross rods was used to power an Accucraft Ruby chassis which it did easily. The boiler with no cross rods only managed to turn the chassis over continuously at very low speed. So a small diameter boiler using cross rods will be made for the Ruby also a pressure test rig for the flue will be made.

Regards Tony.

 

[Tony Bird]

Hi,

Test rig made to check 15mm flue tube of boiler to be made. As the fitting of cross rods seems to improve a boilers performance it was worth making a test rig.

The flue fits over a plug to centre it and seals on a fibre washer, the test pressure is the same as the boiler 120psi for a working pressure of 60psi.

Regards Tony.

 

[exairman]

Hi I am building a Darj & Him class B the boiler is 42mm od by 200mm long and has flue tube 18mm od it is more or less a copy of Keith Bucklitch,s design with the raised fire box. I bought gas burner from Roundhouse but on testing it in the boiler the flame shot through to the smoke box threatening to set every thing alight within it,s vicinity(wife not impressed I was using the potting shed table at the time). Could it be that the flue tube is too small for the poker dia0.375"? Perhaps my boiler is too long for this burner?.I was very interested in the idea of inverting the burner as with such a small diameter boiler with a fairley large flue tube there is not a great deal of water coverage above the flue tube. Grateful for any advice on this problem . Regards

 

[Tony Bird]

Hi,

Welcome to HMEM.

Hi I am building a Darj & Him class B the boiler is 42mm od by 200mm long and has flue tube 18mm od it is more or less a copy of Keith Bucklitch,s design with the raised fire box. I bought gas burner from Roundhouse but on testing it in the boiler the flame shot through to the smoke box threatening to set every thing alight within it,s vicinity(wife not impressed I was using the potting shed table at the time). Could it be that the flue tube is too small for the poker dia0.375"? Perhaps my boiler is too long for this burner?.I was very interested in the idea of inverting the burner as with such a small diameter boiler with a fairley large flue tube there is not a great deal of water coverage above the flue tube. Grateful for any advice on this problem . Regards

I am not familier with the Roundhouse poker burner but I will try and help. It could be any or a combination of all your suggestions. A couple of questions;

Does the burner work well out of the flue and does the gas valve allow small adjustments to the flame?

As the gas is turned up does it blow the flame out?

Is it possible to see a photograph of the burner lit?

Regards Tony.

 

[exairman]

Hi Tony many thanks for your kind assistance l have tried to send you some pics but l suspect they won,t go. Got the wife a tablet for Christmas and l am using that as the regular is not talking to me anymore. I have real idea how down load the photos and l have found the forum rather difficult. So l don,t know if they have gone or not. Hope to from you shortly Best Wishes

 

[Tony Bird]

Hi,

Alas no photographs or PM's.

Does the burner work well out of the flue and does the gas valve allow small adjustments to the flame?

As the gas is turned up does it blow the flame out?

If the flame outside the flue tube burns well and is controlable then the burner is possibly too large in diameter for the flue.

See if you can manage to post the photographs.

Regards Tony.

 

[exairman]

Hi sorry to be a pain but l am having troubles find my way around this forum. I did try and send some pics but they must have gone into hyper space or some thing so l shall try again. When the valve is cracked open the flame evenly displaced but as the valve is gradually fully opened the flame moves along the poker and eventually forms a triangular shape the base being about half the length of tube from the end.lt would appear that the gas at the jet end is not igniting until it meets the flame at the aft end. If l can get the pics to you it will probably be lot easier to understand than my ramblings. Just tried again l still don,t seem to be able to attach the photos l gone through the relevant instructions but to no avail just hope you can make sense of my text. Regards.

 

[Tony Bird]

Hi,

When the valve is cracked open the flame evenly displaced but as the valve is gradually fully opened the flame moves along the poker and eventually forms a triangular shape the base being about half the length of tube from the end.lt would appear that the gas at the jet end is not igniting until it meets the flame at the aft end.

The valve does not have to be opened full, it is often the case that the flame will blow out if the valve is opened beyond a certain point. A smaller jet or a valve with a smaller delivery hole using a needle like the jet in a carburator can reduce this effect. But this might not be the answer.

Regards Tony.

 

[joeb]

Just read the thread - very informative thanks
I am about to do a refurb on a Cornish boiler that I got on ebay
I started a post on it before I read this (search is your friend) and it does not have a burner
the boiler has cross pipes in the burner tube that start about 50mm to 60mm in which would block the type of burner your using
any ideas on what sort of design I could use
Cheers
Joe

 

[Tony Bird]

Hi Joe,

Just read the thread - very informative thanks. I am about to do a refurb on a Cornish boiler that I got on ebay. I started a post on it before I read this (search is your friend) and it does not have a burner. The boiler has cross pipes in the burner tube that start about 50mm to 60mm in which would block the type of burner your using, any ideas on what sort of design I could use.

If it is an old boiler it might well have used a blow-lamp type burner. What size is the flue tube and the over-all size of the boiler? I will try and find your thread. I am away in a warm country which has power cuts using a very slow computer in a foreign language. but back in the UK next week sometime.

Regards Tony.

 

[Tony Bird]

Hi Joe,

Just read the thread - very informative thanks. I am about to do a refurb on a Cornish boiler that I got on ebay. I started a post on it before I read this (search is your friend) and it does not have a burner. The boiler has cross pipes in the burner tube that start about 50mm to 60mm in which would block the type of burner your using, any ideas on what sort of design I could use.

If it is an old boiler it might well have used a blow-lamp type burner. What size is the flue tube and the over-all size of the boiler? I will try and find your thread. I am away in a warm country which has power cuts using a very slow computer in a foreign language. but back in the UK next week sometime.



Back in the UK. A lot colder and damper but the computers are reliable!

I have found your thread on the boiler. From the photographs the flue looks about 35mm ID? A suitable burner might be a ceramic plug type. I have never made one but have a friend who has made many successful ones that produce a lot of heat. I think that several companies that make model boilers in the UK can supply some. If you like I will contact my friend and see what he thinks.

Regards Tony.