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Discussion Starter #1
Does anyone have experience or heard of or have any ideas on adjustable alcohol burners?

The reason for trying to make an adjustable alcohol burner, is that quite often my Aster P8 (BR38) keeps running with the safety constantly blowing steam. This uses water very wastefully, and under these circumstances the feedwater pump simply cannot keep up. I think I spend to much time, and too often, pumping water manually, even compared to my gasfired Maerklin S3/6 (BR18) - wich has no feedwater pump at all! But with that locomotive I very seldom waste steam through the safety - hence my idea. Also, it seems rather common that people run their alcohol fueled Asters with safetyvalves blowing "all the time".


Having run this my first alcohol fueled locomotive - as opposed to gas fueled - I've grown more and more fond of alcohol fueled operation. The only thing I miss in comparison to gas fueled operation, is the ability to adjust burner intensity effectively.


The fact that the auxilliary blower cannot be shut completely, maybee aggrevates the situation. But I have a feeling this added "constant minimal draught" makes only slight difference.


I use a traditional 3-cup burner. I'm thinking of adding a lever mechanism that can slide the wicks inside the burner cups, lowering or raising the wicks some 5 mm (1/5").


Any input?!?

Thanks!
 

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If it is a chicken feed burner, just make the air pipe a bit longer so that the level of spirit in the sump is lower. A bit of push-on flexible tube will do and is easily adjusted.

I would not expect altering the wick position to help, but I may be wrong.

David
 

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Try capping off one of your burners, which is easily done by removing the wicks and placing a little silicone in the top of the pot.
I did this on my Aster Pannier, and the safety blows off less and the run time on a tank of fuel has been extended.

Rob
 

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Pauli, I slide a section of hose over the tank outlet, copy the angle of the pipe. Try sliding it down 2-3mm and adjust as needed from there. I do this on all my Aster engines, the early ones have this from factory.
 

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Discussion Starter #5
@ Jeff and David; I did lower the air-inlet with a bit of rubber tube for a while. However, I then got too little heat. Anyway I wasn't satisfied with the experimenting results. Also, I'm not sure the heat requirement always is the same...So I think I pretty much decided to go for maximum flame / heat ;-)

@ Rob; I'm not sure I understand. Are you effectively making the top opening of the burner cup smaller in diameter?

If so, this kind of reminds me of spirits fired pot-heaters. (Used for example for "Fondue" / melted cheese and other dishes heated on the serving-table.) These pot-heaters have no wick, and you can adjust the flame by turning a ring with air-holes, adjusting how much air is inlet around the actual burner hole in the center. (The burner-hole remains constant.)



Wouldn't it be nice to be able to turn the heat up during steam-up and cold days, and kower it while running a warm summer's day?! :)
 

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I just reduce the outflow of the main tank into the chicken feeder sump. If there is less fuel to the burners there is less fire.
 

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Discussion Starter #8
Charles, doesn't "strangling" fuel supply cause the wicks to burn themselves / incinerate?
 

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I've tried extending the bottom of the pipe on the chicken feed system as Jeff describes with a short length of tubing but I'm not honestly sure it makes that much difference as I think the rate of feed into the burners is determined more by pull (capillary action) than by push.

One idea I've considered is to build a waste valve into the smoke box to control the draught. We all seal our smokeboxes to produce maximum draught but if we could add a controlled air leak then we might be able to control the draught and thence the fire more precisely. Not something I've tried as it means cutting holes in expensive models but the theory seems appealing!
Robert
 

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Posted By Pauli on 11/09/2008 11:36 AM
Charles, doesn't "strangling" fuel supply cause the wicks to burn themselves / incinerate?


After 5 or 6 years running one of my Mikes the wicks "look" pretty bad, they are mostly heavily stained with the red food coloring I put in the alcohlol. Yet, I have not had any problems with them or the fire.

As to putting a damper in the smoke box... I have, in the past, had too much problem with the fire hunting for air by coming out the bottom of the fire box (and subsequently buring the wires to my reverser servo under the smokebox) to want to experiment with that too much.
 

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Pauli,
The simple answer is to open up the blast nozzle to reduce the draft. It may take a few tries but the results will be well worth it. Anyone that scratch builds comes upon this issue and reducing the burner is a last resort.

The best wick to buy is Dick Abbott's Ultimate Wick material which is far superior to any other. Contact me off site if you want more details.

Best regards

Alan Wright
Orangeville
Ontario
 

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Rob Meadows'idea to cap a burner is the way to go I think.. Cap the frontmost pot. Another thing is trim the wicks a bit shorter.

Alcohol fuel is great sport.

Take care, Bob
 

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Discussion Starter #13
Alan, you mean that I should try and make the hole in the blastpipe larger, right? Now that does seem clever!

Funny thing is I've considered extending the blast-pipe all the way up to the chimney rim the way it's done on my Maerklin S3/6. This prevents hot exhaust-gases to heat exhaust-steam, wich increases condensation = the Maerklin always produce great plumes!

Only consideration, is that it kills all draught created by exhaust-steam, making completely dependant on the auxilliary blower.

So maybee it will be solving two tasks at the same time?!? :-D
 

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Pauli,
I would suggest doing things in this sequence.
[1] Reduce the hieght of the wicks above the holders by 2mm
[2] steam and see if the safety valves blow less,
[3] if still blowing too much, trim another 2mm off the wicks, try again..

If you get down to ,say 3mm total wick hieght and its still blowing too much, then you could consider increasing the blast pipe nozzle size, dont attempt to do this with the nozzle in place, remove it , measure the diameter of the hole , open out by , say 0.1mm, re-install it and steam to try the result..you may have to do this 2 or 3 times.going out 0.1mm each time. I would not extend the blast pipe to the stack top.. negates the whole "Stephenson" boiler system.

There is an additional change and that is to repack the wicks, with more strands ie: tighter. this also reduces the alcohol take up and reduces the fire strength..try one thing at atime and note the result. good luck.

Gordon.
 

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One thing that I have also noticed is that if you replace your wicks with stainless mesh (As per Jeff Runge article at Southern Steam Trains) they seem to not burn as hot. I do not understand why, but have noticed this in my Mikado. All these suggestions will help, but it is what it is. Alcohol, in a chicken feed system will never be as adjustable as a butane burner. But it's advantages are the fun of using a blower, no burner roar and not having the problems associated with butane in cold weather.


Thank's Jeff Runge for your stainles mesh wick article, and Jim Pitts for providing at your own expense such a great web site as Southern Steam Trains.
 

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At one time there was a rather long thread about this, but just for the record ---- I have a factorky built lP 8 that runs great with the standard Aster fire box for this engine.

You might try going to the Aster design to see what happens.
 

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You could do all the adjustmenst suggested but it is much easier to match the train to the locomotive. I have had this problem also and it was solved by matching the size or length of train to the locomotive. Aster have designed this loco to perform with a certain sized train so just keep adding stock behind the loco until all the steam is needed for the cylinders. The train you have behind your locomotive is not heavy enough so the excess steam that is being produced has to go somewhere and that is out through the safety valve.

Also why cannot the blower be closed? The only reason to have the blower working whilst the loco is moving is beacause it is travelling very slowy and pulling a very heavy train and therefore the exhaust from the cylinders (blast pipe) is not enough to keep the fire burning. By running the locomotive at fast speed with the blower on combined with the two cyliders working will of course use up water at a prodigious rate, much more than an axle pump could keep up with.

A locomotive at stand still with the blower on uses alot water, in fact it is possible to empty the boiler at standstill with just the blower slightly on, this is why the handpump is used to fill the boiler as the axle pump will not work until the locomotive is moving. When my loco starts to move I never need to use the hand pump, the blower is closed completely and the axle pump takes over the job of keeping the boiler at the correct water level. The speed of the locomotive is then controlled through the bypass valve.
 
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