Childhood Project Revisited

[rockets]

Hopefully this is the right part to post this. Admin, please relocate if needs be.
Having been a member of this forum for years, I am finally getting around to posting something relevant. About 35 years ago, our father gave my brother Carl Wilson, also a member on here, and I, a large wooden box of Meccano which he had exchanged for a case of beer with one of his shipmates. As well as the fantastic haul of Meccano, most of which was 1930s, there were two small model steam engine cylinders. These looked home made and probably dated from the same era. As children, we immediately decided that we would build engines with these, despite having no lathe or other means to do so!
Fast forward about 35 years and the Meccano and one of the cylinders is still around. The other sadly seems to have been lost over the decades.
I have three children of my own so I've decided to fulfill the childhood idea and complete the engine for my boys to mess around with. The lathe is used to making parts for motorbikes so it can have a change. I'll post as I make progress as and when time allows. Not very ambitious compared to some projects on here, but hopefully it will get me back into making models again. I have a 54" motor yacht laser cut which needs to be built and the plan is to build a E T Westbury design engine for it.
Hopefully pictures of the cylinder and a piston and rod I've made will appear below.
Rockets.

 

[chucketn]

Rockets, I can understand your desire to build an engine from the bits you have. I built my first engine, a wobbler, from materials found in my Dad's workbench, sadly a few years after he had passed. He would have really enjoyed this hobby...
And, on a side note, I noticed your location in your signature. I was stationed at RAF Upper Heyford during my USAF career, and lived in Duns Tew. Two of my children were borne in Oxfordshire, one in Banbury, one in Oxford. Good memories.

 

[rockets]

Rockets, I can understand your desire to build an engine from the bits you have. I built my first engine, a wobbler, from materials found in my Dad's workbench, sadly a few years after he had passed. He would have really enjoyed this hobby...
And, on a side note, I noticed your location in your signature. I was stationed at RAF Upper Heyford during my USAF career, and lived in Duns Tew. Two of my children were borne in Oxfordshire, one in Banbury, one in Oxford. Good memories.

Thanks for the kind words.
I'm currently serving at RAF Benson. I hope you enjoyed yourself over here.
It's really important to me to finish this engine after all these years and pass it on to my children.
Rockets.

 

[chucketn]

Well rockets, I hope if you need any help, you'll ask...I did enjoy my tour there. In fact, after a nasty divorce, and a second tour in your beautiful country, this time at RAF Lakenheath, I married a local girl and brought her home with me. Been happy for over 30 years now...

 

[rockets]

Chucketn,

It's a small world because my wife is ex USAF and from Seattle. We met whilst serving in the Middle East.
I'll certainly ask for help.
Many thanks
Rockets.

 

[chucketn]

From the picture you posted, that is a cylinder, built up type. Also, I suspect it is a wobbler type cylinder. You're in luck, mate! I've built a couple of those.
Research Wobblers or Oscillating steam engines, and see if you can find a design that suits you. Then, spend a hour or two with a scale, calipers, or what ever measuring tool you can muster. Get all the dimensions of the part you have, and make a sketch of it. Measure the bore, the length, the width, the thread of the stud sticking out... We have the technology... We can build it!
Sorry, got carried away... But, we do need to know the dimensions of what you have in order to suggest what engine to build around it. If you need to, Pm me with any questions you may have...
BTW, where in Oxfordshire are you?

 

[chucketn]

Oh, forgot to mention, in addition to sketches, take pictures of the part you have, From all angles/sides. That way we can determine critical dimensions that will help us determine what engine to make from what you have, or possibly what engine it was meant for.
And, it would be a help if you tell us what tools/machines you have at your disposal to build the engine you want.

 

[rockets]

Chucketn,
Yes it's an oscillator or wobbler. It's just going to be a single acting simple engine. I have some dimensions jotted down which I'll share next time I am in my shop. I have a Maximat V10P lathe with a milling head fitted. I believe these Austrian machines were quite popular in the States. I also have a bench drill and a large amount of hand tools. I'm an airframes fitter by trade.
I'll take some better photos too.
I'm based in South Oxfordshire, near Wallingford. Not far from Henley on Thames.
Rockets.

 

[chucketn]

I'll have to look up a map of Oxfordshire to put you in perspective, as it's been 40 years + since I was in that area.
O.K., now that we know it's a wobbler for sure, the critical dimension is from the center of the stud shown in your pic, to the center of any valve hole in the cylinder on the side that has the stud sticking out. That side is known as the trunion face and the threaded stud is the trunion pin. The cylinder would pivot on that stud. Oh, say so if you are familiar with this terminology... I don't want to be preaching to the choir, as they say here in the south...

 

[chucketn]

Rockets, do you know if the cylinder is single or double acting?

 

[rockets]

Hello,
Yes I'm familiar with the terminology, I built one from set of castings a few years ago, for another boat (I like boats!). This one is also single acting, just the one port on the cylinder. I'll get some dimensions and give you a clue what I intend to do with it. This one will be very simple, just to run on a table top, not to power a project.
Regards, Rockets.

 

[chucketn]

I'm learning to use Fusion 360 to model engines and 3d print the parts to cast in aluminum. I recently finished a single action single cylinder wobbler designed by Harry Wedge. I'm now working on a vertical slide valve engine designed by C.W. Woodson and published in an article in Popular Science before I was born.

BTW, the wife's Dad was career RAF... She knew the Base your stationed at...

 

[fcheslop]

The cylinder looks like a Mamod or maybe a Bowman one
I have a few toy engines dating from 1880 to the mid 1960s if you need any dimensions just ask
cheers

 

[rockets]

Chucketn,
That's cool. If she was an East Anglia lass she may know RAF Marham near Kings Lynn. I was there too as well as various Scotland postings.
Fcheslop,
It may well be although it has a fairly home made look to it close up, like hand finished. It has a 1/8 BSW thread on the trunnion. Thanks for your offer of help.
Regards, Rockets

 

[rockets]

I have taken some measurements of the little steam cylinder I intend to build a simple engine around, just to hear it running and close the loop on a childhood idea!
I work best in metric mode being a 1973 build year myself but I imagine the originator worked in inches.

The bore is quite worn and was probably 5/16 when new, a piston I machined at a shade under 8mm seems fit well.
Stroke is 7/16, or just over 11mm
The distance from the trunnion centre to the centre of the port should I think be 3/8, but is measuring at 0.385" or 9.78mm. This would have been made to tolerance as the port is 0.0615" or 1.6mm. I imagine it was drilled at 1/16 and the drill was a little under.
Thanks for taking an interest,
Rockets.

 

[chucketn]

I have some info on the layout/design of an engine. You interested?

 

[rockets]

Chucketn,
I'm very interested. Always willing to learn something.
Do tell!
Rockets

 

[chucketn]

First is a simple simulator for oscillating engines, from the U.K even! Neat program. It has 4 engines built in, which you can animate. The neat part is you can change dimensions of various parts to see what effect it has on the engine.
You can download the program or run it online.

http://www.labbookpages.co.uk/metalwork/steamSimulator.html

The second bit of info that might help you build your engine is to diagram the relationship of the crank arm length to the piston length to the port location.
Get out your compass, the grade school drawing type, and some paper. Draw a circle representing the crank arm. the center being the center of the crankshaft, the circumference representing the center of the crank pin as the crank rotates. The diameter of this circle also is equal to the desired stroke of the engine. You have that info. Next, measure from the center of this circle, the distance equal to the length of the piston and rod from the center of the hole that goes on the crank pin, to the center of the piston/rod connection. Draw a circle at that point, who's radius is equal to the distance from the center of the trunion pin to the center of the port on the cylinder. You still with me? Now draw a line, tangent with the crank pin circle at the top, through the trunion center, until it crosses the trunion port circle at the far side. Repeat that line from the bottom of the crank pin circle, through the trunion center point through the port circle. Where these lines cross the far side of the trunion-port circle represent the intake and exhaust ports of the trunion.
I have a drawing in Fusion that shows what I'm describing, I just have to export it. I'll post it in a few minutes. I hope you can follow my explanation above. I can't remember which book/website I got that from...

 

[rockets]

Chucketn,

Yes, I'm with you. I'll draw that out tonight and take a photo. I'll also have a go with the simulation. Thanks very much. It's great to post on here and get the help and encouragement.
Rockets.

 

[chucketn]

Found my labeled diagram...