# Wick Art



## SalM (Jan 2, 2008)

I am doing the wick's of a Accucraft BR Britannia......it comes with no wicks in the burner. I have it close to making the right amount of steam but I have a few questions.

How high above the tubes should the wicks be............mine are 1/2 inch

Should you "mushroom" out the top of the wicks..........mine are not....

I am using Piedmont Steam Supply wick material. I started with 26 strands and I now have 18 in each tube......On the fan it will make steam in about 4 minutes and the pressure will be about 50 lbs.

It stars out smartly but after 2 laps on the track it runs at 30 lbs. At this pressure pumping water and pulling a small train the performance is weak. There is no smell of unburned alcohol so I could remove a few strands 

from each cup but before going further I would like some comments. I know there are some members out there with the right answers....please help if you will......Sal


----------



## JEFF RUNGE (Jan 2, 2008)

Sal. make sure the smoke box is sealed.. any air leaks make for poor drafting.


----------



## David Leech (Dec 9, 2008)

Hi Sal, 
I don't know what the Piedmont material is so ..... 
Using the supplied Ultimate Wick material, I did one for a friend and about 3/8" is sufficient. At least he steamed it, although I wasn't there and he said that it produced sufficient steam. 
I just left them sticking straight with no 'messing'. 
Whatever wick material is used, it should be loose enough to 'almost' fall out if the burner is turned upside down. 
This will allow room for the fuel to 'wick' up between the strands and burn at the top. 
Each locomotive is different, weather is different, the tracks are different and the trains pulled are different, and somehow you must find the correct solution! 
I think that you have it right, it IS an art, and you may have to try a couple of times to get it right. 
Good luck, 
All the best, 
David Leech, Delta, Canada


----------



## SalM (Jan 2, 2008)

I've made a check (as best I can) for any air leaks in the airflow stream from the burner to the smokebox.......nothing obvious. The burner tubes with 18 strands were in no danger of falling out so I removed 2 strands in each tube. I did a test fire outside of the engine for balance. The fire seemed even and steady. I put everything back together and will give it a run tomorrow, weather permitting. Thanks for your input. I know of several engines out there....one with 25 strands, one with 22, and one in Canada with the OEM wick material and all make enough steam. Maybe tomorrow I'll have the answer.


----------



## SalM (Jan 2, 2008)

I ran the engine this afternoon on rollers and still could not maintain over 25/30 lbs of steam. If I stop the engine and put on the fan it quickly gets to 50 lbs. run the engine again even with some blower
and it gradually drops back to 25/30 lbs. Guess I need to look for something else.......maybe the blast pipe is not correct to maintain a draught for the burners...the fan can but not the exhaust. I am quiting for today.


----------



## zephyra (Jan 2, 2008)

I've been "wick tuning" an Aster Duchess on rollers just this afternoon. One thing which can be very helpful is to use a small inspection mirror to actually see what happens to the flame under various conditions. I use a cheap dental mirror to inpsect the burmers when the machine is up on rollers.


If the fan is creating a good draft, then is likely that the smokebox is adequately sealed. If the engine is running well under pressure then the blast pipe is probably clear. Checking the alignment of the blower nozzle and the blast pipe is fairtly easy but these are hard to get wrong.


Next run, close the blower as soon as the engine starts running. Under most circumstances - and certainly on rollers - the blast should give more than enough draft and I even suspect that interference between the blower and the blast could reduce draft in some circumstances as the two jets of air combine in the smokebox. I never use the blower once the machine is moving as my experience is that opening the regulator and blower at the same time just reduces performance. 


If the issues continue, then the problem is more likely with steam leaks elsewhere and fine tuning the wicks is very unlikely to make any difference as I've concluded that as long as they are not too tightly packed, then it is hard to go wrong. I cut them to 15-20 mm and don't try and shape them in any particular way.


Out of curioisty, I make a very short video a while back showing the way the fire leaps into action when the blower is opened. Not a realistic test, but illustrates how the blower works...


----------



## SalM (Jan 2, 2008)

I think you are real close to the problem.......

My burners do respond to the fan....they also respond to the blower....but any combination of blower and exhaust or exhause alone reduces pressure........as you suggest the exhaust probably interferes with the blower and reduces overall draft. 
As far as checking the alignment of the pipe this is new ground for me....it appears to be dead center of the stack at the base of the cylinder block. The blower pipe is smaller and off to the side at a small angle, it works OK as I can build
pressure on the blower alone. 

Checking the alignment of the blower nozzle and the blast pipe is fairtly easy but these are hard to get wrong...........any info might solve my problem...............Thanks Sal


----------



## nsimpson (Mar 15, 2010)

Hi Sal, 
I am the Canadian that David Leech helped cut and pack wicks for the Britannia (my first alcohol fired steamer). What is your oil consumption like? I have found that my steam oil resevoir is nearly dry at the end of a run and am wondering if perhaps insufficient lubrication is contributing to your steam loss. As you have said, your pressure is fine even with the blower cracked, so the losss is happening in running and I would be more concerned with that than pipe alignment and wick heights. You have a good fire when it is drawn properly so too much steam is going somewhere when you are running. I am not running Britannia at the moment as I am installing name plates and transfers, but the next time I run it will be on rollers with a higher viscosity oil to try and keep oil flowing throughout the run and to observe the right setting on the water bypass to keep the boiler at the right level also. 
Cheers, Neil.


----------



## Dwight Ennis (Jan 2, 2008)

I will preface by saying I have no experience with alcohol firing at all. I do have a bit of experience with a 1-1/2" scale coal fired loco however (still learning). Something Neil said jumped out at me, so I thought I'd comment as no one has mentioned it yet. 
and to observe the right setting on the water bypass to keep the boiler at the right level also. 
On my coal fired loco, constantly feeding cold water into the boiler via the crosshead pumps causes pressure to drop. Sometimes, especially when I know I'm approaching a grade soon, I need to completely open the bypass valve to one of the two pumps to reduce water injection and allow steam pressure to build before I hit the grade. 

I have no idea if cold water injection is causing any part of your problem, but you do say it steams fine until it starts moving. I'm also assuming that the Britannia has an axle pump from the comments in this thread. My suggestion is to run her for a few laps with the bypass all the way open and no water injection into the boiler and see if performance improves. It's just possible that you're putting too much cold water into the boiler and reducing steam pressure by cooling things too much. 

Just a thought (and possibly a lame one). Might be worth a shot though.


----------



## David Leech (Dec 9, 2008)

Sal, 
When you removed a couple of strands, did you also cut the wicks down to 3/8", or are they still at 1/2"? 
If there is not sufficient 'head room' above them, they will not work correctly. 
With the suction fan, you may be making them do something that they cannot do naturally when in normal use. 
Just a thought. 
All the best, 
David Leech, Delta, Canada


----------



## SalM (Jan 2, 2008)

Neil...oil use seems normal.....I still have some after a "run". I keep the oil pressure valve closed per the instructions.......at 40 or plus lbs the engine runs really well.......but it appears the exhaust blast wont provide the needed draft.
Dwight.....you can tell the load of the axel pump when its "on"........but it needs to keep pressure up while pumping or in bypass...it makes about 25/30 lbs no matter whats going on......except if you stop the engine open the blower only or put the fan on the stack....in no time I have 50/60 lbs.
David I did cut the wicks back to 3/8 of an inch.....the head clearance from the wick tops to the boiler plate seems good.......it looks like a "C" type boiler where the flame go's back to the backhead then up and forward thru the boiler to the smokebox, all enhanced buy a draft created by the fan or blower or blast pipe. Under blast pipe control my engine under performs. Seems like I am learning more about this system than I planned for. Thanks for ALL you input.


----------



## David Leech (Dec 9, 2008)

Sal, 
Okay, assuming that you have checked that all the wicks are burning, and look 'good' when the suction fan is on, or with the blower open, then I don't "think" that it is a wick issue. 
It still may be, but maybe not! 
In steam, with suction fan removed, and blower closed, I would open the throttle, and then slowly let the loco roll forward while holding the palm of your hand above the smoke stack. 
Make sure that you can feel four distinct blasts against the palm for each revolution forward. 
This will determine that the blast pipe is coming straight up, and also that there is not a blocked exhaust passage somewhere. 
Of course, you could just send it back to be fixed! 
I'm sure that we can eventually help you out somehow if you don't mind having to keep trying.
Do you have anyone close by that can give you a hand? 
All the best, 
David Leech, Delta, Canada


----------



## Charles (Jan 2, 2008)

Sal
How about blow by at the cylinders...


----------



## SalM (Jan 2, 2008)

David...the exhaust is strong and pronounced right after raising steam....but gets weaker as the pressure drops.

Charles....I ran the engine with the drain cox's open and there appeared to be no steam blow by...only 2 distinct chuff for each side.

David ...although the exhaust beats are strong they may not be "targeted" to the stack in order to create a vacuum in the smokebox....just a guess right now.

Royce called Cliff for me so there may be more info to come..........Thanks Guys


----------



## Mark Scrivener (Jan 7, 2008)

Sal, 

Dwight has a good point - if the axle pump is replacing water faster than you are using it, then the pressure will slowly drop. Basically there is too little steam space and too much (cold) water. I wasn't clear from your response if you had tried letting it run a lap or two with the bypass closed so the axle pump was dumping water back to the tender and not the boiler. 

The opposite situation can also cause a pressure drop - too little water. 

I don't have the Britannia (beautiful engine BTW), but I do have a Berk (alcohol and axle pump) and a K-27 (butane, no axle pump). All 3 are somewhat similar size models, and running the Berk is a totally different experience from the K. It is very easy to get too much or too little water in the Berk, and when you do, it slows down and doesn't want to pull, and usually you can see a pressure drop. With some experience I've learned to keep the water level correct (unfortunately the sight glass on my berk isn't that reliable, don't know about your Britannia, but the Berk sight glass level can be completely independent of the boiler level). Once you get her sorted and figure out how she likes to be run, I bet that Britannia will pull a very long rake of cars for as long as you care to keep dumping fuel and water into the tender.


----------



## SalM (Jan 2, 2008)

Neil and others with the Britannia........ looking down the Stack you can see the blast pipe at the base of the stack and the blower pipe off to the side at about 11 o'clock. The hole in my blast pipe is a loose 1/16th of an inch.
I measures it with an allen wrench and then measured the wrench. It is much larger than the blower nozzle hole.......does yours look like mine or are the 2 holes just a little different in size with the blast pipe being a little larger.
Thanks for looking...Sal


----------

