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WOW It is starting to get shape! Well done and good looking!:)

To bad that the thread: four cylinder Heisler was not stored in pdf form, photos are lost.
About the cylinders and the power of steam:
Do you use or imply formulas to calculate the size and stroke, the free swing(the back pressure of "old steam") ect or just copy the real life size and scale it down?
Perhaps i am over complicating.

I don't think it is doable to buy for every project different sized reamers.
What is your tolerance between the piston and cylinder walls?
And why dont you use ?gasket/gaschecks? around your pistons

It seems to me also that you have a solid "recipe" for the cylinder and valve sizes.
Your valve, the steam regulator on top of the cylinder is also a very tight fit, or you have a blade spring mounted on top of it?
Probably you wrote a thread on it, i did not have a lot of time lately to read all of your fine threads.

A bold question:
Do you have by chance of this built some pictures of the "fresh steam supply/connection" to the cylinders?

I fully understand the technical working principle of real live steam engines, per part and the whole machine, but i must work on my technical English for this subject, all my study books are in my native language sorry i hope you understand what i am trying to translate:)
Scale models are a bit different than there real life working counterparts:cool:.

Thanks in advance, Best Igor
 

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Discussion Starter #23
Thanks Igor
Live Steam & Outdoor Railroading have a multi part series covering the Four Cylinder Heisler build starting next issue.
I usually scale down the actual cylinder size unless it doesn't make sense. Compound engines used very high pressures (300psi) and mine will be operating at 50 psi most of the time do the 2:1 diameter ratio needs to be reduced in our engines. This one is 3/4" HP and 1" LP which is the same as I used on the Y6 engines I built.
I have reamers up to 5/8" so I just rely on my boring tool to get a nice finish. I usually finish off with a piece of 600 sand paper wrapped around a wood dowel.
Piston clearance isn't critical. I use 0-rings on the pistons and fit them for a smooth sliding fit. I have used rulon rings in the past but prefer Viton o-rings
Not sure what you mean about piston gaskets. I use gaskets on the cylinder end caps.
Because the engine is outside admission, the steam pressure holds the valve down.
I will show the steam connections later in the build.
 

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Discussion Starter #24
I finished the two chassis yesterday and tested them on air. They run great individually and in compound mode,
Here are some photos of them.
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Front engine
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Rear engine
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Love your work, fine eye for detail, my compliments, really amazing!
To order a magazine from the internet, i would like but due to some nasty experience i would not like to order from the internet anymore.
Your cylinder built, you made a single tread about it? or am i wrong, sorry did not have time enough to read all your work(own company, end of the year ect)
I think(almost sure) we are giving different names to the same parts, my incompetence of technical English sorry.
Monday i will have some time on my hands and make a picture of which part i was referring to.
Thanks for the detailed pictures!
If it is not to much trouble, can i ask you to post some pictures from underneath the front engine?
Where the steam enters the cylinders, many thanks in advance....many!
I am not going to question your experience, but from my point of view, the "fresh steam supply" to the rear engine, is that pipe not a bit to small in diameter?
And is that steam heated again by running a pipe thru a "flame pipe" or is the steam still hot enough to power up those cylinders?
Or you just use super dry/heated steam to power them all, so the "cold used steam" from the front engine is still hot enough to make the rear cylinder to work?

Thanks in advance, Best Igor
 

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Discussion Starter #26
Thanks for your feedback
The standard pipe size used by most manufactures is 3 mm which is 2 mm (.078") inside for a cross section of .00485"
I use 5/32" which has a 1/8" (.125") inside for a cross section of .01228"
This gives me over 2.5 times the cross section of what is normally used.
The tubes probably look small because the cylinders are so big.
In the full scale locos, the steam piping is usually insulated and there is a small pipe surrounded with insulation and then covered with larger piping
The steam will be superheated by running the pipe through a flue in the boiler.
 

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Discussion Starter #27
Here are a couple of photos of the steam lines, The black tubing on the steam line is just for testing on air and it will be hooked up to a copper tube from the boiler.
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(y)(y)(y)(y)(y)(y)(y)(y)
 

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Discussion Starter #29
I have finished most of the boiler and the construction is similar to that of the Skookums where there is also a video of the soldering.
The smokebox is a little different from those I have done in the past,
Normally the inside diameter of brass pipe is the same as the outside diameter of copper pipe which makes for a great press fit between the two. My local metal supplier is shutting down his operation this summer so he has stopped carrying copper pipe. I have been going to plumbing supply houses and checking out their remnates. I was able to get a 2-1/2" by 32" piece for $30 cash

The stack is two pieces a base and the stack tube.
The base needs to fit the curvature of the smokebox which is 2.75" so I set my fly citter to 1.375" and machine the 1" bar to that radius.
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I then turn the shape of the base and part it off. The stack is turned from 3/4" stock. The through hole is 1/2" and it is bored out to 5/8" at the top. It is trimmed to 9/16" where it goes through the smokebox.
The attachment was with some weird looking studs which I duplicated and then drilled holes in the base and silver soldered everything together.
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The front cover is flat with 50 rivets. The hole in the center for turning on the arbor is usually cut out for the smokebox door but because of the air pumps, the door is located below the center line so I covered it up with the air pump mounting bracket.
The rivet holes are drilled on the mill with the DRO circle function


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Number 4025 had several changes and we are doing the 1950 version with the steam generator behind the stack and two number boards in font of it. The generator as in most of my builds will be non functional but will emit steam through a valve in the cab.
The following photos show the boiler set on blocks at the correct height above the chassis. You can also make out the man door below the Accucraft air pumps.
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I am amazed again, such an eye for detail.
To bad you did not post the boiler build, i will read on your suggestion to see if i can get my answers...
You make it look simple(from my point of view), there must be a catch somewhere.
great job, big thumb up

With best regards Igor.
 

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Discussion Starter #31
The steam take off is through a steam dome near the center of the boiler. The scale position is used. The bronze bushing is threaded to 7/16 -32 and the working steam dome is turned with an o-ring grove which will hold the scale dome.
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The boiler cover will have a wagon top section which is flat at the bottom and tapered at the top. In order to support it, tapered wood strips are glued in place and then fiberfrax is wrapped around it. Then straight wood strips are used for the rear of the cover.
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.032 brass sheet is then annealed and bent to shape to form the wrap. the dome goes on top of the sloped section so the bottom is formed in a similar way the the stack pieces but with the bar held at an angle to compensate for the slope.
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There are two oval shaped sand domes on the rear of the boiler. I have found that the easiest way to do these id to first make a wood form. this can be cut on the band saw and sanded to shape and fit.
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I can then wrap card stock around it and trim it with an exacto knife
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I then transfer the shape to brass sheet
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And cut it out, anneal it and silver solder it together. A 1/8" thick top is cut to fit and soldered on.
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I don't have a source for 1/32 whistles so I have to make my own. The contraption behind the whistle, I am told, is a centrifugal blowdown.
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Looks great Bill, Im sure it will be done long before July, though July NSS doesnt look promising for the state to open to larger indoor events in time. Waiting to hear back from the guys on their decision.
 

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Discussion Starter #36
Thanks Jay
We in the Bay Area are hoping the vaccinations will have things close to normal by then. CA is stepping up the cycle using dentist and pharmacists to do the injections now
 

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Bill, super impressive as always. What soldering technique do you use to connect parts to the boiler casing and how do you hold the parts in place.. My attempts to solder small parts to large brass surfaces always go horribly wrong. I am currently trying to build a new cab roof for an Aster K4 and it has been a comedy or errors. Any hints and tips much appreciated!

Robert
 

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Discussion Starter #38
Thanks Robert
For soft soldering...
First off, I use nothing but Staybrite solder and flux. It seems to flow much better than others I have used.
Next always direct the heat to the largest piece (mass) and gradually move towards the smaller one.
Place a snippet of solder in the joint away from where you are heating and this will let you know when things are hot enough to solder.
The biggest mistake most make is trying to heat the solder and not the base metal.
 

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Discussion Starter #39
Also, on holding the things in place, I sometimes spend more time making jigs for soldering than making the part. I have a bunch of soft foundry bricks and use music wire pins to keep things together and I also have u shaped clips I have made from music wire and coat hanger wire. These work for things from 1/16" to 5" or 6 "
Soldering things on to a cab roof should be fairly easy using the clips. They can be bent to shape with pliers to get the needed shape and tension. On the right is one of the pins.
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