# Double Fairlie Construction



## bille1906 (May 2, 2009)

August 25th I started construction on a 1/16 scale G gauge Double Fairlie. So far I have the center section about 75% completed. My friend Dennis Mead is drawing up the running gear and we should be ready to start on it in a week or so. I am posting some pictures in response to a question by someone in another thread. I will continue to post pictures and try to answer questions about the construction as I go along.


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## nadnerbster (Nov 19, 2009)

*wow* 

Nice work! Will be very interested to see how this one turns out. 

I'm a rank amateur doing a kitbash, so mine wont look anywhere near as good as this . . .


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## Pete Thornton (Jan 2, 2008)

Just curious - you do mean 1/16th scale not 16mm:1ft (SM32) ?


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## bille1906 (May 2, 2009)

Yes it is 1 : 16 or 3/4 scale
The original runs on a 2' (1' - 11.5" actually) Gauge track. This scales out to 1 : 13.3 for 45mm track and 1:19 for 32mm track.
As most of the models are done in the UK on 32mm track, I guess 1 :19 would be the more popular. When I scalled it out, the size seemed too toy like to me on our G scale layouts. I did a scale drawing in 1 :13.3 and it was too big. So I decided on 1 : 16 as a good comprimise and am very happy with the size and the look. My goal is to have a one-of-a-kind locomotive as close in overall look as the original as I can. The scale will add to it's uniqueness. The only drawback is that I will also need to make my own cars for it.


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## Dan Pantages (Jan 2, 2008)

Seeing what you have done so far, I think making cars for it will be an easy task for you.


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## xo18thfa (Jan 2, 2008)

Great job on the plate work. That kind of effort really pays off in the end. In 3/4" it will have crazy power on Ga 1 track.

Please keep us posted on this job. Thanks


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## David BaileyK27 (Jan 2, 2008)

Having built several Double Fairlies at 16mm scale I compliment you on your effort, I must admit that getting working Stephenson valve Gear in between the frames was a challenge, but having worked on the full size engines I can vouch for the lack of space when oiling up. 
My model engines were gas fired and to scale, I tried several different types of boiler, one with two burners, one with one Ceramic burner and one with Meths firing, the biggest problem is that on Merddin Emrhys the side tanks are very small so I had two gas tanks, if I ever built any more I would change the design to use new ideas that I have. 
David Bailey DJB Model Engineering Ltd


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## bille1906 (May 2, 2009)

The close quarters is one if the things that steered me toward the larger scale. I plan on having two gas fired boilers with the valving and servos inclosed in a faux firebox. I want a throttle regulator, whistle valve, and possibly a boiler vent valve all with RC. In addition to this, I will have a servo at each engine for reverse and maybe a servo for the cylinder drains. We have it on CAD but making everything fit may be a horse of a didfferent color. My tanks are about 1" X 1.9" X 5". I will be using two for water, one for RC equipment and one for gas. The gas tank will be slightly smaller to allow for the outer cover with the rivit detail.
I would love to see a shot of your work and any ideas you may have for this project.
I was also wondering if you know about the outside pumps on the original. The photo I have looks like there are two central oilers driven by what would normally be a valve timing crank and on the other side there is something that looks like an hydraulic pump. I am still trying to figure out how to fit the feed water pump in and that may be a way to incorporate two low volume pumps into the system


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## David BaileyK27 (Jan 2, 2008)

There are no pumps on the Double Fairlies, only two injectors below the centre footplate, the machanical lubricators are a later addition added in preservation days, the original engines had hydrostatic lubricators in the cab.
If you contact me off group I will send pics of my engine, I have the general arrangement drawing which shows all the details.
David Bailey


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## bille1906 (May 2, 2009)

Here are some shots on the progress. In the first shot, you can see how the throttle will work. Dry steam is drawn from the steam dpmes on both boilers and directed to the throttle valve mounted in place. The two smaller fittings will attach to "S" shaped tubes which will be silver soldered to the SS superheater tubs which will run through the burner flues. You can just see the blue servo directly below the valve which will work the throtle. The two open tubes on the other side of the valve will have 1/8" copper tubes soft soldered in for whistles and other accessories. The long connector at the bottom will be drilled out to hook up the clack valve (still in design) 








The next shot shows the fire box cover and the site glass and pressure gaige. these will be the only visable conections as everything else will be covered by the fire box. This side of the fire box has rivited plates over the door openings and the other side has two faux doors 










This final shot approximates the final look. the two front tanks are water tight and plumbed for feed water. the rear tank will be used for RC equipment. The other tank which isn't finished will be for butane. Still need to add the exhaust stacks, Steam dome/ pop off valve and cover assembly, and what I think were sand tanks which will be used by me for dead leg lubricators and go in front of each side tank.


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## David Leech (Dec 9, 2008)

Bill, 
We met at the Sacramento NSS this year. 
This looks like quite the project and the brass work looks great. 
There appear to be no photos in your last post, so not sure if it shows the two boilers. 
Why not just have one long boiler, but with a central burner and flues going both front and back? 
Just a thought! 
All the best, 
David Leech, Delta, Canada


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## bille1906 (May 2, 2009)

I'll try this again 
I thought of doing a central burner and even doing a coal fired one but I think both would be too complex for me as this is only my second project. 
I may have to put these in and then go back and edit them to get them to work.


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## David Leech (Dec 9, 2008)

Hi Bill, 
That's better. 
I am assuming that the steam from both boilers just enters into the valve, and then the throttle spindle is below this point. 
Okay, now IF you have steam from boiler A at say 50 psi, and boiler B at say 40 psi, when the steam enters the turret will the steam pressure from A actually STOP the steam from B from entering the turret? 
I have no idea what happens when you try to combine steam from two sources that may NOT be at the same pressure! 
I guess that you will find out. 
It may be that you will in reality only be using the steam from one boiler. 
Anyway, the painted body looks great. 
All the best, 
David Leech, Delta, Canada


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## David Leech (Dec 9, 2008)

Hi Bill, 
I have just looked at the photos again and realised that you have the boilers connected by a pipe at the bottom, so that will equalise the pressures, I think! 
Oh well, I'm sure that you know what you are doing. 
All the best, 
David Leech, Delta, Canada


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## bille1906 (May 2, 2009)

Thanks David 
The throtle valve is also a "T". There is a 5/32 hole drilled through the block which should equalize the pressure, water level and to some extent the temp. With the top and bottom connection tubes, we should have something very close to one boiler. The tube sticking out of the top of the boilers is part of the steam pickup at the backhead. these will be covered with a steam dome which will have a pop-off valve on top. Usind a pop-off on each boiler should prevent uneven pressures and let me know if one boiler is building more steam than the other. 
I plan on using the same butane burners as I did on the Garratt. They work well and seem to burn evenly. I will use only one butane valve but leave room to add a second if needed to equalize the temp.


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## HMeinhold (Jan 2, 2008)

Bill. 
as long as the cross section of the pipe from the gas valve to the jets is 10x the cross section of the jets you can expect equal pressure. This rule of thumb is used in many applications which need equal pressure. 
Regards


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## Stan Cedarleaf (Jan 2, 2008)

Bill... What a masterful job of crafting. It's just fabulous.


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## xo18thfa (Jan 2, 2008)

The plate work looks gorgeous. How did you do the pin stripe?

I follow the plumbing. I think it will work. Everything appears equalized.

When you say "central burner" do you mean one gas jet, one mixer chamber and then branching to two burner tubes? That should be OK. If you go with two sperate burners, I would suggest a seperate valve for each. If there is any difference between the jets, the gas could follow a path of least resistance. One burner is just right and the other starved. A lot of Accucraft K's have trouble keeping both burners lit. I think that's the problem.


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## bille1906 (May 2, 2009)

The pin striping was easier than you would think. 
I got some 3M 1/16" automotive striping tape on line - #70102 
I have two different size rectangles. I took blue masking tape and cut it to the demensions of the inside of the pin striping. 
I then cut out the corners of the tape to where I wanted to start and stop. 
I then laid the striping tape next to the edge of the masking tape with an inch or so overlap at the start. 
I then with a new razor blade, cut the start and finish points by holding the blade in the tape and pulling up on the overhang. 
The little reverse radii were done with a #1 lettering brush after the masking tape was removed. That part of the job is a little shaky but the original was hand painted so I guess it wasn't perfect either. 
The central burner we were thinking of was either a coal fired one or more likely a butane one with a ceramic burner and two tubes or possibly an alcohol set up. 
The reason I am going with two burners is that it is simpler and alows more room for steam valves and servos. I will have three servos in the fire box area and four if there is room. 
I know about the K problems but I believe that was a production problem. 
My last project was a Garratt and we made our own burners and jets and both burners seem to perform fine. That being said, I plan on leaving room to add a valve should one burner burn hotter than the other and it can't be corrected by changing jets.


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## HMeinhold (Jan 2, 2008)

Bob, Bill, 
if you adjust the "manifold" cross section as indicated above, you won't have problems. We use this rule of thumb every day at work to make jets distribute a flow evenly, as it ensures equal pressure. 
Regards


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## xo18thfa (Jan 2, 2008)

Posted By HMeinhold on 25 Oct 2010 12:26 PM 
Bob, Bill, 
if you adjust the "manifold" cross section as indicated above, you won't have problems. We use this rule of thumb every day at work to make jets distribute a flow evenly, as it ensures equal pressure. 
Regards 


OK, I see. Only have to set it once. That's one for the shop notebook. How much adjustment to the cross section do you usually have to do?


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## HMeinhold (Jan 2, 2008)

Bob,
no adjustment is needed. Let's assume 2 jets with 0.004" diameter. So the cross section of both together will be 
0.002" x 0.002" x PI = 1.25 x 10E-5sqi or 2.5 x 10E-5sqi for both. The rule says that the tube or manifold has to have at least 10 times this cross section to guarantee the same pressure at both jets. So a tube with a diameter > 0.04" inner diameter should be sufficient.

Regards


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## xo18thfa (Jan 2, 2008)

Posted By HMeinhold on 25 Oct 2010 05:13 PM 
Bob,
no adjustment is needed. Let's assume 2 jets with 0.004" diameter. So the cross section of both together will be 
0.002" x 0.002" x PI = 1.25 x 10E-5sqi or 2.5 x 10E-5sqi for both. The rule says that the tube or manifold has to have at least 10 times this cross section to guarantee the same pressure at both jets. So a tube with a diameter > 0.04" inner diameter should be sufficient.

Regards





I got it now. I was asleep before.


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## bille1906 (May 2, 2009)

Progress report:
I have been contemplating ball bearing eccentrics for a while. I found these skate board bearings that fit the bill. They are 12x18x4 mm and they were $29 for ten on ebay. you can by them individually for about $4 each. As you can see from the photo the bottom eccentric has an additional connector which may be used for an axle pump. In addition to the reduced friction, these sealed bearings should last a lifetime without lubrication.








Here are two eccentrics assembled. one front and the other rear. only one eccentric wil power the axle pump the other three are for valve timing








This is the butane valve that is in the tank. the gas goes in the hole at the top and out the tube in the bottom. It's hard to see here but the threads on the needle valve are ground off on the sides to allow the gas to pass through.








Here are the two components of the tank ready to be silver soldered together. The material is .040 brass which was bent at 45 on two adjacent sides.
Soldering was done similar to boiler soldering and the finished job was pressure checked at 100 psi.








Finished tank will be covered with a rivit detail shell matching the water tanks. This dosent show it but there is a well nut braised on the bottom for mounting.








There are four tanks on the frt corners of the Fairlie which I think are for sand. I am using two for dead leg lubricators. Here is a shot of the valve I made. it is just a piece of 1/16" copper tube threaded to 0-80 and capped off with a piece of 1/8" hex drilled and tapped with an excape hole drilled sideways at the bottom of the hole. I have a C-16 which I have done the Hottman conversion to which uses 1/16" tubing and it runs a little too wet for me. I am thinking I will end up throttling it down about 50%. I made the threads very tight by not going all the way taping the cap. This should prevent it from backing off.








The tube and valve are now soldered in place. The 1/8" hex can be adjusted with a 2-56 nut driver








The double Fairlie has what I think is a vacume brake pipe which looks a lot like the one on the Round House single Fairlie. I was thinking about getting two from them but my scale is a little different and I didn't want to wait for delivery across the pond. besides, this was more fun.
I go to Home Depot from time to time and get copper ground wire from the bulk rolls. I try to keep gauges 14 - 8 in my shop. I buy 3' lenghts and ask them not to coil it as it comes off the large spool with no kinks. This material bends better than anything I have found and is what I used for the fitting at the top. The prototype has this very accute bend which could only be done with this wire. I think this was 8 ga but I just selected the one which looked the best. After it was bent, I cut it to length and drilled holes in the ends to hold the pieces in alignment during soldering. The raised ends were turned out of brass . The stand pipe is 1/8" brass rod. the lower base was turned out of brass and threaded to 2-56 on one end and drilled to 1/8" for alignment. The core of the bent pipe is 14 ga copper wire and the wrap is string.








Here is the pipe and lubricator in place 








The Fairlie will have two sets of whistles The two tone will have I high pitch Britishsound and the three tone one more American. Blown together, they have a five whistle tone that is very distinctive. Note the SS screws which have been turned to needle valve. These are used to adjust the steam volume which gives it maxium volume without overblowing. You can se from the scratched paint, this was not a total success the first time around. I have tuned them with air pressure at 60 psi but they may sound different under steam








Here is one of the chassis frames. Bare bones at this time...More to follow


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