Gas burner

This topic has 16 replies, 8 voices, and was last updated 21 July 2011 at 09:38 by doubletop.

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20 June 2011 at 15:00 #1019
clive swinney
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@cliveswinney28133
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20 June 2011 at 15:00 #70589
clive swinney
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@cliveswinney28133
I have nearly completed my first locomotive, it is ERIC from Steam trains in your garden. The gas burner is a10mm brass tube with fine slots cut into it and one end sealed. This fits into a 19mm tube running lengthwise through the boiler. The burner lights well outside the boiler, but will not light in place, the flame coming out of the end of the boiler tube in the smokebox. Does anyone have any experienceof this or suggestions. Thanks Clive

Edited By clive swinney on 20/06/2011 15:00:56
20 June 2011 at 15:49 #70591
David Clark 13
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@davidclark13
Hi Clive

I would join the following 2 email groups if not already a member.

The first one, you have to request to join.

The second one just join.

They are both full of 16mm modellers, many who are building Erics.

regards David

Beware the list owner, stray off topic at your own risk.

<Steammodelloco16mm.yahoogroups.com>

<[email protected]>
20 June 2011 at 17:58 #70606
clive swinney
Participant
@cliveswinney28133
Thanks for the information David, I will try these groups.
20 June 2011 at 18:02 #70608
Richard Parsons
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@richardparsons61721
It looks as if you are getting No secondary air into the 19mm tube or no draft through it. A short bit of pipe in the chimney with a little bit of pipe blowing up it with a foot pump. There is a sketch of this thing in the book of the Titch by LBSC. It induces a draft through the boiler.

Rdgs Dick
20 June 2011 at 18:47 #70611
Jeff Dayman
Participant
@jeffdayman43397
Hi Clive,

Sounds like the gas pressure may be too high. Can you reduce it some way?

With small gas fired models I have built, the gas is turned on low as possible, let a few seconds go by and then I light the fire at the chimney or at the open smokebox door. The gas flares with a ‘woosh’ or ‘whump’ and then the flame front travels right back to the burner and settles down over it. After a few seconds the smokebox door is shut if open. Again gas pressure has to be low as possible for lighting up, in my experience.

Note about induced draft and exhaust blowers with gas models – I personally have not had luck with either, they tend to lift the fire off the burner and when that happens the fire can go out or at least become unstable for good steaming. Your mileage (and others’ mileage) may vary…..

JD
21 June 2011 at 11:07 #70638
doubletop
Participant
@doubletop
Clive

I have tried exactly what you have described , even to the tube dimensions being the same, and had the same results. As Richard suggests its a secondary air problem and not easy to resolve. I came to the conclusion that poker burners are only any good in any open environment say for a hedgehog or basic water tube boiler.

See link below

http://www.homemodelenginemachinist.com/index.php?topic=9111.0

I think I then moved on to a blow torch type burner pointing down the 19mm tube and the poker became a nice ornament.

Pete
21 June 2011 at 20:02 #70658
Steambuff
Participant
@steambuff
Clive,

I have poker burners in all my 16mm loco’s, and I will have in the Eric I am building.

All Roundhouse, Accucraft etc 16mm loco’s use poker burner’s, so therem is not a long with them, I admit that they can be a pain to get working correctly.

Have you joined the steammodelloco16mm yahoo group yet? They should be able to help. (Brian Wilson the books author is a member and he often offers help.)

Dave
19 July 2011 at 15:52 #72099
Dave Bond
Participant
@davebond87219
As a slight side topic are gas fired boilers the same as a coal boiler? So for example could a coal boiler be retrofitted with a ceramic or equivilent burner?

If this is the case are there size limitations for using gas, would it be practical to fire a 5″ steam loco on propane?

I ask this not because I would move away from the sight and smell of coal but just as an interesting thought as I see Maxitrack have gas fired locos and I wonder if there are differences between the two boiler types.
19 July 2011 at 16:00 #72102
Steambuff
Participant
@steambuff
Yes and No

In general a Coal fired Boiler/Firebox could be converted to fire from a Gas Ceramic burner. (In the 16mm NG world – TME do this, they can supply the 3 firing options Coal. Gas or Meths or all 3)

In the 16mm NG world a boiler designed for Internal Gas firing cannot be used for Meths or Coal, firstly it has no firebox …. the usual design is a single tube running through the lower part of the boiler, into which a ‘poker’ gas burner is inserted.

Dave
19 July 2011 at 16:03 #72103
Dave Bond
Participant
@davebond87219
Ok the thought I had was a multi tube fireboxed boiler that would normally accept coal as a fuel. So I imagine a ceramic burner as the heated ceramic would resemble a fire bed as a coal substitute? Also it would be a more even heat ??? I am only guessing here hence exploring this idea on the forum.
20 July 2011 at 07:34 #72141
doubletop
Participant
@doubletop
Posted by Dave Bond on 19/07/2011 15:52:15:

As a slight side topic are gas fired boilers the same as a coal boiler? So for example could a coal boiler be retrofitted with a ceramic or equivilent burner?

If this is the case are there size limitations for using gas, would it be practical to fire a 5″ steam loco on propane?

I ask this not because I would move away from the sight and smell of coal but just as an interesting thought as I see Maxitrack have gas fired locos and I wonder if there are differences between the two boiler types.

I run my Rob Roy (3/.5″) on propane using a ceramic burner based on a commercial version that I believe came from Bruce Engineering. One of our club members runs his Manor (5″) on gas . And a guy in Belgium I’ve been communicating with has converted an OSLiveSteam Rocket (5″) to gas. If you trawl through the American sites you’ll find a lot of them running 7.5″ locos on gas. These are a mix of ceramic and jet type burners. The only change to the boiler is a stainless ‘arch’ which restricts the direct draw down the flues and stops the flame being drawn off the burner. Check out link here.

http://www.homemodelenginemachinist.com/index.php?topic=10883.0

Pete

Edited By Doubletop on 20/07/2011 07:59:11
20 July 2011 at 08:18 #72142
doubletop
Participant
@doubletop
An example of what I’ve called ‘jet’ type burners

http://www.livesteam.org/MartyBurners/

Pete
20 July 2011 at 08:24 #72143
Dave Bond
Participant
@davebond87219
As gas burns hotter than coal is there any issues with the proximity to boiler sides, would deflectors be used?

In your above comment I take it the deflector described would be like a brick arck in a full sized loco?
20 July 2011 at 11:46 #72168
doubletop
Participant
@doubletop
I would suggest that it doesn’t burn that much hotter than coal, it is more consistent over a larger area rather than hot spots that I’d guess coal is prone to. You have way more control and can shut down immediately which you cant to with coal.

I’ve secured my ceramic with Permatex hi temp RTV (for car gaskets) and its holding up well. It does not burn as a fiercely as the gas torch you’d use to make the boiler.

Take a look at the link I’ve posted for pics of the stainless ‘arch’. Arch what the guys call it but its probably only remotely similar to the real thing.
20 July 2011 at 12:19 #72170
Ompa Ompa
Participant
@ompaompa11814
Just to add my twopennyworth…..I currently run a 5″ gauge ‘Brit’ (Lookalike) on Propane. I use a total of six ‘Marty Type’ burners in a configuration that gives me the chance to run either two, four or six at one time. On full six I can maintain around the 90 psi mark. One issue I have is with the cost of gas, my choice to use it, so can’t complain. I am still experimenting with additional items such as an arch, ceramic infills and some others, all to improve heat retention. I do use a small amount of steam to create a permanent draught at standstill with natural exhaust when running doing the same job, just as with coal firing.
21 July 2011 at 09:38 #72224
doubletop
Participant
@doubletop
On the subject of gas. In NZ the only thing readily available is LPG which is a propane/butane mix. The trouble with this is the propane burns off first leaving the butane so the calorific value drops dramatically when the bottle gets about 1/3 full. If you get the bottle refilled at a petrol station they just top it up so now youv’e got less propane. And so that goes on until you either burn off all the butane by some other means than running your loco. Fortunately our local BOC purge the bottles before a refill and a fill of a 3kg bottle is about $12 or 6 quid so you are only chucking away about a pound or two each time.

I did ask BOC about pure propane but when they started talking about couriering the empty bottle up to their lab in Auckland it got obvious than it would be more than 6 quid a fill.

Pete

Edited By Doubletop on 21/07/2011 09:40:44
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