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A toasty HOT welcome to

STEAMSHED.COM


A Part Finished boiler
PYRTE - Ready For Action


A small sample of some of our work

PYRTE


You are interested in owning your own live steam engine, right?

Maybe you fancy chugging around with an engine of your own?

Sure, you've seen other people's steam engines running and have been fascinated as you watched all the moving parts with steam blowing all over the show, but I'll bet you want something just a little bit bigger than those fiddly little models you see almost everywhere.

You want something that will pull you round, something with a bit of uumph that you can be proud of, something with a bit of guts rather than a dinky model that just sits there and spins when you light her up?

You want a live steam engine that does a bit of work, one that'll  perform when you want it to, something with a bit of grunt, but you need one that is not too hard to build; maybe one that any novice can make no matter how little they know about steam engines?

Then you may be in just the right place...


Welcome to the world of PYRTE...

Right here you can learn how to build an easy Pull You Round Traction Engine


PYRTE ready for the offThis live steamer, at 26 inches long (66cm) and weighing in at around 60 lbs bone dry (27kg) may be just what you are looking for.

She runs at 50lbs pressure and can pull an adult around easily, is dead simple to build, and is very economical on the pocket.

Any novice to model engineering can build this engine... I proved it...

I've had her for around ten years now... Ok, she's been changed a bit since she was first started, but you can easily build her yourself using my experiences so you don't fall into the same traps I did.

She takes around 100 hours to complete from start to finish and you can reckon on around three or four times the price of a brand new Mamod to give you an engine that will pull you round with ease.


Take a look at PYRTE in action here and see how she pulls.

Ok, maybe she's basic and doesn't have all the bells and whistles on, but as a first step in your live steam engine building, she's pretty good and needs nothing more than the intermittent and simple use of a three and a half inch centre height lathe and drill press to build her – nothing complicated - and no expensive castings needed.


Take a look at these snippets from the different chapters of the build, that way you can see if PYRTE suits you...    Whether you feel you will be able to complete her and whether she will meet your needs or not.


Part of the Boiler Build

Next we go to the back end of the boiler.

The same process needs to be done here with the pressure/anchor ring, but before this is done the rear 13-gauge plate needs to be marked and drilled for its necessary parts.


Firstly, you have already marked out the vertical centre line, along with a central point you used to draw the circumference.

If you trim it down to just fit inside the rear of the barrel, and with the line upright, then from the top outside edge of the pressure plate, along that line, make a mark at ½ inch (13mm) down (the top water gauge/steam outlet hole). A second mark needs to be made at 2½ inches (65mm) down from that same outside edge, (these are for the water gauge, and need to be drilled ⁷/₁₆ of an inch (11mm) diameter. With a further one at ½ inch (13mm) up from the bottom to act as the feed water inlet/drain-off fitting, and drilled at the same size.

The fourth one, the central point, needs to be drilled out at ¼ inch (6mm).

Boiler BushThe next item on the agenda is to produce three phosphor bronze bushes threaded internally at ⁵/₁₆ x 40 teeth per inch – see drawing - being ½ inch wide for ¹/₁₆ (1.5mm) and reducing down to ⁷/₁₆ inch(11mm) wide for ³/₁₆ of an inch (5mm).

(If you are planning on buying the fittings for your water gauge, rather than making them yourself, then stick with the internal imperial size as metric is not available commercially so far – that I am aware of).

One point here is that you should not use brass for your bushes as brass tends to corrode slowly with water and heat and will fail over time, whereas bronze will definitely outlast your model traction engine. This is the reason that bolt-on fittings are made of brass as they are more readily replaced when faulty (although twenty or thirty years is no problem for brass fittings).

Once these items are completed, the second pressure ring can be shaped and drilled in the same way as the front end, but for the final assembly things need to be altered a little.

Firstly, you need to produce three nuts at ¼ inch deep from the 3/8ths inch (10mm) hexagonal phosphor bronze rod, tapped ¼ x 40 (6mm x 1), and the bronze rod needs centre drilling and ¼ x 40 (6mm x 1) threads running down for ¾ inch (19mm + ) at both ends as the rear 13-gauge plate needs the bronze rod nutting to it with the end of the rod level with the top of the proposed outside nut and the inside nut pinched tight up to the plate.

Doing it this way allows the remainder of the rod to sit inside the barrel and just poke through the front central hole by ¼ inch (6mm), once you have drilled the front plate’s central hole out to ¼ inch (6mm) which is ideal for the remaining nut height on the front end, which will be added later, once the back end is soldered.

The rod needs to be in place to support the rear plate about to be soldered, and if the barrel is sat on a flat surface on its front end, then the rod should hold the plate in the right position, with the rear edge of the back pressure ring being beautifully in line with the back end of the boiler barrel.


Firebox and Tender Construction

Next we need to mark out the bolt holes for the boiler support rings (the two pieces of ¼ inch square brass – to be installed soon) and this is achieved by using a compass and drawing a 4 inch circle on a plain sheet of paper and dividing the circumference into 12 equal sections with your compass, (you could even do it on your front sheet, using a centre punch at the centre of the boiler centre line) a simple child’s school compass does the job, and by drawing from one point through the centre of your circle to the opposite point, you then can position the scribed centre of your plate with the centre point of your circle at the centre height of your boiler.

Mark each of the 12 points where they cross the 4¼ inches diameter circle, and these will be your bolt hole centres.

The 3 upper and lower holes on your front plate (not really marked properly on the drawing above for both top and bottom horizontal anchor rods - allowing the fire-box top plate and the fire-box bottom plate to be added later on) now need marking, so scribe a line across the top of the front plate at 7 /₁₆ inches above the bottom edge, with a mark from each side edge at 1¾ and one in the centre. Repeat the marking at the bottom making the centre height at ³∕₁₆ inch up from the bottom.

With all bolt hole points centre punched lightly, and this time, with two or three holes bored inside the 4 inch circle on your front plate with your 3.5mm drill, line up the plates (both the front and back, with the bottoms and sides level), clamp them together once they are lined up correctly and drill the plates for the bolt holes within the 4 inch circle, using the front plate as a guide for your drill.

When bolted together through these holes, do not pull them apart until all your plate work drilling on these items is completed, and all the marked bolt holes are drilled out. As you go on, insert more bolts in the perimeter holes and nut them tightly before removing the few original ones in the central boiler barrel hole (to be), that way the plates remain together for the removal of the central hole.

The large centre holes for the boiler needs to be chain drilled, (that simply means drilling holes very close together to form a line so that a hacksaw blade can be inserted in the drilled “slot” to make it easier to remove the bulk of the 4 inch circles) or alternatively can be drilled a much larger size to gain entry for your hacksaw blade.

A little tender usage of a file will be needed to remove the inside of the 4 inch circle, and you will need to check that the boiler barrel slips in the holes without any snagging. A very small amount of clearance is preferred, but do not overdo it as the bolts will need some sheet metal to anchor onto, and any irregularities in these plates will be obvious on your completed traction engine.

While they are bolted together, scribe a line right across the top of the back plate to show the height of the front plate, (this is to show the top of the rear anchor rod  sitting level with the upper dashed line on the drawing above).

With everything complete so far, the plates can be separated and the lower air/access hole in the rear one now needs marking out and removing.

This, basically, provides access for the burner and an ignition point, as well as air entry. So scribe a line across at  inch up from the bottom, with a further one at 1 up.


Rear Axle and Drive


The rear axle on PYRTE is basically a simple 12 inches long x 3/4 inch diameter steel shaft, supported by two phosphor bronze bearings attached to the side plates of the tender. It is live - meaning that as the crankshaft rotates the axle turns.

The drive from this axle is carried to the driven hubs by key steel sat in keyways cut into this shaft and from there by the rear wheel drive pins on to the rear wheels.

In effect, these axle keyways lock the live axle to the driven hubs, one on either side of the tender and bearings, that way allowing the wheels to be engaged or not through drive pins, either together or individually.

The hubs, being locked onto the rear axle, keep the axle in position and all that is needed is both ends of the outer diameters of the axle shaft reducing down to ½ inch for a length of 1¼ inches for the wheel bearings and a further ¼ inch at the ends turned to ⅜ diameter to accommodate the wheel retaining bushes and a small hole drilled through each bush and axle end for the locking pins to keep the rear wheels in place.

Between the crankshaft and the rear axle is an adjustable lay shaft carrying the necessary gearing to allow a 16:1 ratio to be achieved between the crank and the axle.

Smokebox, Chimney and Perch

To produce the smoke-box tube, square the ends in the lathe using the same method as used in shaping the boiler barrel. The smoke-box needs a top centre line marking for the chimney, and one at the bottom that will need cutting to open the diameter up to fit over the boiler front end. We’ll be filling the gap shortly, so don’t worry too much about that for now.

While you have it in the lathe, at the rear end, a mark at 3/16ths is scribed around the circumference showing the drilling points for the bolts (or rivets – brass nuts and bolts are easier, and the heads can be shaped to look like rivets if the mood takes you, once they are installed) that hold the smokebox onto the boiler barrel.

I used brass countersunk screws, 4ba again and nutted on the inside, with the outer smoke-box countersunk to allow the tops of the screws to sit flush (allowing easy smoke-box removal if need be for any painting and maintenance that may be required) with a view to having the insulation and the outer boiler sheet (cladding) covering them and held in place by bright brass boiler banding.

A mark on the top line for the centre position of the chimney saddle is needed at 1½ inches from the front edge. While it is still in the lathe, extend the chimney saddle marks before and aft (2¼ and ¾ inches) from the front along the top and also scribe very lightly 1½ inches either side of the top line, roughly at 1½ inches from the front again – what you will be doing is to bore a hole in the top to fasten the chimney on with, and these marks allow you to centralise the chimney saddle).

At the front, a “door-plate” to fasten the smokebox door onto is needed and is silver soldered into place, although before this is done the smokebox needs to be split along the bottom line (the perch line, the underside) from the front to the back and the enlarged smokebox diameter made to fit onto the boiler barrel.

Once you have cut along the bottom line, you need to produce two circular plates to match the outside diameter of the boiler barrel.

Mark two circles in the 13-gauge sheet, at exactly 4 inches in diameter (to match the outside diameter of the barrel), with the front one having a second mark at 3½ inches in diameter (this is the smokebox door size to allow centralisation of your smokebox door) and a third at 3 inches in diameter (the front access hole). This one is your door-plate – a thinner plate, say 16-gauge, is fine if you do not have enough of the 13-gauge, as these plates are under very little load at all.


Cylinder Assembly

Right... Onward, fellow metal knockers, enough of the pre-ambling... Let us begin with the marking out...

New brass cylinder blockTake your brass block and make sure all the sides are square and flat.

The main part of the motor stands 2½ inches high with the regulator steam chest sitting directly on top, flush with the left hand side to allow the valve chest (bolted on the right hand side of the block) and the block to look central as a unit.

The bore is also offset to the left to allow steam transfer ways for the cylinders to be drilled at the right hand side of the cylinder bore.

Please note: All marking points and dimensions should be taken or measured from the same point or face to provide accuracy. The best option here is to work from the base, the left hand side and the rear face (driver’s side).

From the bottom face mark a line faintly at ½ an inch up all the way round. (This gives a guide for how deep the metal removal is needed for the base – the steam chamber).

A second line needs marking from the bottom on the back at 1½ inches up to provide the centre height for your cylinder, with another on the right hand side at ⁵/₁₆ inch up and ¾ inch along from the rear face (the steam inlet point for your motor).

From the left hand side, a line needs making at 1 inch in on both the front and the back to show the vertical centre position of your cylinder, and these two marks need extending to the base to give positions for lining up to the base plate for the centre of the cylinder position for assembly purposes.

A third point needs marking on the left hand side to show where the drain is for the steam chamber which also aids in starting the motor from cold, so from the rear measure 1 inch, and from the base measure ³/₁₆ up.

Centre-punch the crossing point for the cylinder centre and the steam access point over on the right hand side, along with the steam chamber drain on the left hand side.

Crankshaft and Timing

Crankshaft webbingThis will give a crank throw of 1¼ inches giving a swept volume of 0.98 cu inches (just over 16cc) in total.

Centre punch accurately on both crossing points on the marked web and a ⅜ radius can be marked from the lower point with a ¼ inch at the upper one before drilling squarely into each of the webs at the 1 inch mark with a drill size of ¼, then turn a piece of brass bar down to a tight fit for the hole.

Once each web has the burrs removed, then with a web showing the centre punched crankshaft centre, sitting directly on top of one with no mark, and the turned bar forced in the holes, locking the two webs in line, drill through the two webs at the second centre punched mark, making a point of keeping them locked together in your drilling vice while all the drilling operations are carried out.

This will need to be drilled relatively small at first, but I recommend starting it off with your ¼ inch for the stiffness within the drill, otherwise a smaller drill may wander off line causing your crank to wobble in use, before opening the hole out to ⅜.

The drill should produce a hole just a nadgers oversize, which fits in well with the silver solder needs, but we shall be checking on that soon.

Before removing from your drilling vice, insert a short piece of ⅜ brass rod through it, that way securing it in line, and I recommend hitting the brass with a centre punch to broaden the ends to wedge the pieces together.

The rounding of the webs now needs filing down to the radius marks with the square edges rounding off.

It is wisest now to mark the opposite faces of the webs with a fine scratch so that they can be kept in that same position and look matched when assembled.

The pieces of brass can now be removed and we shall move on to the main crank shaft.

This is very simply a 9 inch length of ⅜ ground steel bar and can be pushed through the two webs. (The 9 inches is a little too long, but by leaving the extra on, it offers a way to turn the motor over for running-in purposes and can be removed on completion).

The ¼ rod can also be placed through the upper ends of the webs, but do not be tempted to remove the main shaft between the webs as this will be removed once the assembly is soldered.


Wheel Construction

That’s the wheel bearing sorted, so now you need the wheel rim fettling.

Using a 5 inch diameter tube, with a wall thickness of ½ inch, (you will need three of these, 2 for the wheel rims and a further one for the flywheel (3 x ¾ - plus an allowance for cutting) making a length overall of 2½ inches. Cut off your first wheel at ¾ and after facing the tube, skim the inside until a complete cut is taken all around.

Many model engineering suppliers carry this size as it is commonly used to make the wheels of steam locomotives.

Front wheel rimWhile in this position, a further cut on the inside needs taking for ⅜ of an inch back and ¹/₁₆ of an inch wider, that way ending up with a diameter of 4⅛ inches. This basically allows the wheel plate to sit inside the rim at a set position, resting on the lip that can be seen in the picture.

Take a cut on the outside face at ¹/₁₆ deep x ⅛ back from the front face. (This is one side of the tyre effect and will be needed on the other side soon – as seen below).

Turn the wheel rim around in the chuck and grip it on the inside, using the newly cut inside lip as a stop (assuming your chuck jaws are deep enough, if not, then the rear face will be up against your chuck jaws) to be sure the rim is sitting square before facing off the sawn face and trimming back until a width of ¾ inch is remaining.

Skim the outside face until a complete cut is observed and cut out the other tyre effect at ¹/₁₆ deep x ⅛ back from the front face.

This is the first version of the front wheel used – the easiest to build, although I produced the spoked wheels once I had a little more time, and there's now an 8 spoked insert available, along with kits for the tender and firebox already cut to shape - 'T' section rear wheel kits are in the offing too.

Right, fellow metal knockers, the full instructional updated book is available for the reduced price of £21.67 for the download and I hope this has given you an idea of how easy this model is to produce and re-inforces your urge to build your own live steam traction engine.

And the best of it is you are offered a full 60 day refund guarantee on the download if you are not happy with the book, for any reason at all. More than likely you will feel it is good value for money, but if not, all you need to do is drop me a line asking for your refund, letting me know the problems so that they can be ammended for other future users, and you get to keep the book anyway.


Help is always available with emails if you get stuck with anything and you can be sure I'll do my best to respond that same day from steamshed@gmail.com.


Just think, this robust live-steam engine could be pulling you around in three months from now, at around seven or eight hours per week that is, and if you get the urge to make it more personal to yourself, like making the wheels look more spokey rather than discs, fitting proper steering rather than push-rod, then that is up to you (but it takes a lot more time) and they will be covered as a free download in the near future on www.steamshed.com.


I'm sure that once you have PYRTE built and working her heart out for you, puffing great clouds of steam up in the air as she pulls you round - as you're watched by others who are in the same position you are in now - with her crankshaft spinning so fast in front of your eyes and the trunk guide piston almost a blur, that when you have a bit more experience under your belt, you will move on to a more demanding model and keep PYRTE as your plaything so that you can get your steam fix when the need takes you, just like I do.



Go on... Download this inexpensive ebook through the secure banking company PAYPAL (it's totally safe for you) and get cracking now! You've got the 60 days to make up your mind!    You know you're safe and you know you want to. 



Remember...   Any problems at all, email me at steamshed@gmail.com and I will sort it out for you.



George.




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