Boiler Construction Photographs.

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Tony Bird

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Hi,
Last week I built a boiler for a friend who had designed it for use on a 16mm scale locomotive. Following is a series of photographs taken during its construction which I hope are found interesting. Starting with cutting the copper barrel and tube plate.
001MakingaboilerplansLR.jpg
002MakingaboilercuttingtubeLR.jpg

003MakingaboilerturningtubeLR.jpg
004Makingaboilertubeplate1LR.jpg

005Makingaboilertubeplate2LR.jpg
006Makingaboilertubeplate3LR.jpg

007Makingaboilertubeplate4LR.jpg
008Makingaboilertubeplate5LR.jpg


Continued on next post.

Regards Tony.
 
:bow: :bow: :bow: :bow: :bow: :bow: :bow: :bow: :bow: :bow: :bow:

Well that showed me a thing or two, Absolutely brilliant thank you for sharing such great work.
Malc
 
Tony,
That's about as clear and well-presented a small boiler tutorial as I have seen . . . and essentially without captioning. One thing I can't see is why rolling/raising a bead (for lack of the right term) on a tube end was necessary, or where this was used (which would probably explian why.) I've built quite a few dozen such boilers and haven't come across a need for rolling a bead into a tube but your setup is quick and clever.
 
Hi.

Tony,
That's about as clear and well-presented a small boiler tutorial as I have seen . . . and essentially without captioning. One thing I can't see is why rolling/raising a bead (for lack of the right term) on a tube end was necessary, or where this was used (which would probably explian why.) I've built quite a few dozen such boilers and haven't come across a need for rolling a bead into a tube but your setup is quick and clever.


It's a hang on from when I made a lot of multi-tube boilers. It stops the tubes falling through the tube plate at the fire box end of the boiler on assembly, it might even give a better joint. I also use to make the fire tubes a couple of different lengths for use in multi-tube boilers, to make it easier to get them through the front tube plate after soldering them into the fire box tube plate.

Hope this explains.

Regards Tony.
 
Tony, thanks for taking the time and effort to post these pictures. Very nicely done and very informative to those of us who have never made a boiler.

I am planning to make my first boiler in the near future and it will be about the same size as yours. What is the diameter and length of the boiler tube and flue you used? Also, where did you get the plans?

Thx...
Chuck
 
Hi Chuck,

I am planning to make my first boiler in the near future and it will be about the same size as yours. What is the diameter and length of the boiler tube and flue you used? Also, where did you get the plans?

The plans were sent to me by the guy that wanted a boiler made to his design. It is a fairly standard configeration. A 6.25" long x 2" OD 16g (about1/16" thick) copper tube for the barrel and the same thickness copper for the tube plates with a 22mm OD flue copper tube with five 1/4" OD copper cross tubes. The fittings bushes etc are bronze and it is hard soldered (silver) together. If you need any help when you start on a boiler please ask. This boiler can be fired with either a poker or ceramic plug burner.

Regards Tony.
 
Thanks, Tony. My boiler will be just a bit larger. The copper tube I have is 2.75" diameter with a wall thickness of .080". It seems like there are an awful lot of holes and fittings in the boiler. Is there any way you can identify some of them? For example, I've attached a photo showing a section from the drawing shown in one of your photos. Not sure what that little tube leading from the front of the boiler to the larger fixture on top is.




BoilerPart.png
 
Chuck,
That is the dry pipe. It turns up in the steam dome and supplies dry steam to the backhead of the boiler.

Dan
 
So the steam enters the end of the dry pipe in the dome? And is then fed down through the dry pipe and out the back of the boiler? Sorry, I'm not familiar with a lot of the terms used in boilers. Is the purpose of the dome and this arrangement to minimize the amount of water that enters the dry pipe? Also, googling boilers and dry pipe, I found a lot of the dry pipes, especially on full size boilers, had many holes drilled into the bottom so condensed water could drain back into the boiler. Would the model dry pipe also have holes drilled in the bottom?

Thx (for your patience)...
Chuck
 
cfellows said:
Would the model dry pipe also have holes drilled in the bottom?

IMHO not if it takes it's steam from a dome, the dome is the water reducer/steam collector. If the stop valve is on the top of the drum without a dome then usually, the underside of the stop is connected to a dry pipe running horizontally along the inside top of the drum/shell. It is blanked at each end, drain holes are fitted at the bottom of each end blank and it has holes or slots along the top to allow the steam to enter the pipe. Both the dome and the underside dry pipe are means of trying to even out the take off of steam from the whole of the water surface in the boiler.

The term dry pipe is a pretty loose expression as any steam leaving the shell or steam drum of a boiler will have some water present probably a dryness fraction of 0.8-0.9.

Hope this helps

Best Regards
Bob
 
Hi Chuck,
As has been said the pipe inside the boiler is there to collect the steam from well above the water. As I expect you know the temperature of the water in the boiler is well above its boiling point so when steam is drawn some of the water changes into steam. As this causes the water to surge upwards in the area of steam collection the steam pipe is often arranged to be well above the surface of the water hence the stem dome so water doesn't get in the steam pipe. Another way of doing the same is to have a pipe running the length of the boiler close to the top of its barrel. This pipe is perforated on its top side and closed at its end so the steam is collect along the length of the boiler and there is less of a surge.
The same applies in models it is a good idea to collect the steam from well above the water. If you are making a stationary boiler a steam dome can be almost anywhere on the top of the boiler. Also the internal steam pipe isn't necessary a valve can be fitted into the side of the dome to take off the steam. As the boiler constructed is for a locomotive the steam dome is in the middle because like the full size locomotives the model has to go up and down hills so the water in its boiler can build up at either end. I happen to know that the guy that designed this boiler has a very hilly garden railway.
The boiler fittings. Starting at the front halfway up on the left hand side is a bush for a boiler feed clack. Next is the dome with a thread for a safety valve in its top. Above the rear tube plate a turret threaded for the gauge glass and pressure gauge. The rear tube plate has bushes for a regulator and gauge glass.

Hope this Helps.

Regards Tony.
 
Hello again,

Forgot to mention there are two blind threaded bushes on the top and bottom of the boiler, the bottom ones hold the boiler to the chassis, the top I don't know possibly to secure false sanding domes.

Regards Tony.
 
Great build documentation. This is the clearest set of instructions available. Should make this into a complete PDF file and put in the download archives.

Domes serve a valuable purpose. Gauge 1 loco's bump around a lot and water sloshes inside. Domes provide an area to collect steam reducing risk of collecting water too.
 
Really nice work Tony - thanks for sharing :bow:

A couple of questions if you don't mind...

Did you use different melting point solders for different stages of the build?
For the dry pipe - did you pre-solder it to the steam take-off bush before soldering the bush to the boiler end plate?

Thank you, and kind regards,
Arnold
 
Hi,

Great build documentation. This is the clearest set of instructions available. Should make this into a complete PDF file and put in the download archives.

My computer skills are limited, I do not know how to create a PDF file. I would be more than happy for someone else to do it. I could add some text if it was thought to be needed.

Did you use different melting point solders for different stages of the build?

No. Easyflo no.2 for all joints. Iron binding wire was used to hold parts previously soldered that might move in a subsequent solder. See black line in photograph of the boiler while it was hot. It was used here to hold the soldered steam turret in place while soldering the regulator and gauge glass bush into the back head or rear tube plate.

For the dry pipe - did you pre-solder it to the steam take-off bush before soldering the bush to the boiler end plate?

The steam collecting pipe is made of thick wall copper tube which was threaded and screwed into the regulator bush then the thread was soldered over before soldering the bush with its attached steam collecting pipe into the rear tube plate.

Regards Tony.

 

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