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[tobyker]

Well having asked about silicone tubing in another thread, (thanks for all answers) I found the boiler in the shed, and it DID have a safety valve. On the base I found a twin oscillator I cobbled together from two Stuart ST engines, about 30 years ago. So far as I remember, I found a bit of brass tube that the crankshaft fitted into, drilled out both engine standards to fit the o.d. of the tube and cut the standards leaving the front third of the shaft bore on one standard, the middle third on a foot, and the aft third on another standard. I then fitted them all together on the brass tube, and soft soldered them all together, taking care not to get the tops of the standards too hot. So far as I remember I lengthened the crankpin by sliding a piece of brass tube over the pin, sliding the pin I'd cut off the redundant crank into the tube, silver soldering it all up and then filing all the brass off to leave the longer steel crank pin. Then I cut the web on the crank pin to balance the weight of one piston and connecting rod. like it says in the books about V-twin bike engines (the only way to go!!) It all sems to work far better than it should or I deserve. It seems to self-start really well when its hot, so I may have to make a steam/exhaust distributor reversing block. However, as the ports are rather awkwardly placed, I may need to open out the drillings at the top of the standards. Does anyone know how the plugs are held into the tops of the standards? IE are they tapped in, threaded, or just a loose soldered fit? I don't think its ever been in a boat, but it has driven a very basic meccano steam lorry. My lad took it to school once and they let him run it around the school hall with all the class watching!. No H&S in those days!.

[kno3]

Great idea to join the two single engines. I've seen them offered on ebay quite often, and not very expensive, this is a good use for them and gives a nice marine engine if fitted with a reversing valve.

Now you should clean it up well and paint and polish some parts 

[Underpressure]

That's a great little engine(s). I have two ST's, they were mounted on a common brass base and linked together by gears into a twin. They were fitted to my first steam boat when I bought it and I eventually got it all going and even made a throttle / reversing valve for it, but it was so pitifully underpowered that the boat used to go backwards in a 5mph headwind  .

Shortly after this experiment I found a local company in Cheddar, who had just started to market a couple of steam engines, a single called the Pipit, much like the ST and a twin called the Puffin. I bought a machined kit of the Puffin and shortly after my model was transformed.

I still have both the ST's, but a base unit hit the scrap bin a long time ago.

Neil

[Martin (Admin)]

How large do oscillator engines go?
 Are oscillating engines just suitable for models?

[HS93 (RIP)]

there where some full sized ones.

Peter

[Colin Bishop]

there where some full sized ones.

Like this one from the paddle steamer Empress which you can see in Southampton Maritime Museum.

Colin

[Martin (Admin)]

 

[Bee]

Weren't the Great Eastern's engines Oscillators?

[tobyker]

Indeed they were - I'm still looking for pictorial evidence to convince Martin. However they also had eccentrics and proper valves, presumably to overcome the oscillator's symmetrical and rather wasteful port timing.

 I have now cut the tips off the standards off my ST twin special, and drilled out the plugs in the steam passages so I can feed steam in at the tops via a reversing block. The original inlets and outlets were just too awkwardly placed to make a neat twin.

[kiwimodeller]

Hi, do you have plans for the reversing valve? I have two 1/2" bore by 3/4" stroke double acting oscillators which I intend to use to power a paddler with both linked to the paddlewheel shaft and timed 90 degrees apart so they will act like a twin and self start. So far I have only found one plan for a valve and it is tiny so any suggestions on what design to use would be appreciated. Thanks, Ian.

[tobyker]

I've no plans for oscillator valves but on the big ones the steam was fed through the trunnions and I think the valves were on the fixed part. Ask Colin if he's got any more photos of the Empress engines from different angles. I will go check such works of reference as I have.

[benjaml1]

Indeed they were - I'm still looking for pictorial evidence to convince Martin. However they also had eccentrics and proper valves, presumably to overcome the oscillator's symmetrical and rather wasteful port timing.

 I have now cut the tips off the standards off my ST twin special, and drilled out the plugs in the steam passages so I can feed steam in at the tops via a reversing block. The original inlets and outlets were just too awkwardly placed to make a neat twin.

http://arnygrimbear.de/GREATEASTERNMASCHINE.htm

[tobyker]

well done - thanks. I dunno why they call it a side lever engine though, as it's obviously an oscillator.
 I've found plans in KN Harris' book "Model stationary amd marine steam engines" for a paddle steamer oscillating twin which has a valve plate between the cylinder port face and the trunnion port face, driven by an eccentric on the paddle shaft. If anyone is desperate to see it I could scan a page of the drawings in. I suspect this valve plate is a model thing - Mr Harris says it was originated by Mr JL Beilschmidt, see Model Engineer 22 March 1934. So I suspect the full size oscillating paddle engines had a more complicated valving arrangement.

[benjaml1]

well done - thanks. I dunno why they call it a side lever engine though,

http://www.fromoldbooks.org/Evers-SteamAndTheSteamEngine/pages/079-Side-Lever-Engine/

[Neil]

I am getting a Mississippi Stern Wheel "Gamblers" Riverboat together, AND with Steam power.
I have been warned off, by those that "know" in the U.S.
There are a couple of kits that look good to me, both somewhat over 1.5 metres.
I have drawings of "OLD" Paddle Boat Engines, but, I am not sure if someone is trying to "con" me. They look authentic, though, but somewhat short on ENTIRE detail..
I think the "V" Twin oscillator would be wonderful, and no HUGE hassles either. It's two Stuart STs stuck together, isn't it?
PM-Research in America make a very good "V" Twin "out of the box", at just US$159+
I have three of them, but am in no way attached to the company, being that my address is way West of there.
A tiny boiler would be the go, in my humble opinion with a feed water set-up at the other end to balance the boat. Then there's a matter of ballast, or, maybe way more important, (on account of the steam, let it ride way lower in the water), so, a huge manipulation of the hull is in order.
That's my opinion, that's all.

I'll let you know how it goes.
(I wonder which boat will win, the Mississippi, or the Imara? Both are in my workshop.)

Neil.

[mogogear]

BTW = Welcome Neil!! Start a thread on your builds and keep us informed - sounds like you have a couple of good projects underway

[Neil]

Hi, and thanks I will try to keep you informed.
Sorry for mis-reading the original message, my vision isn't what it used to be, neither is the rest of my body as it happens. The type face on this forum is quite small, isn't it?
I have a handful of STs here, and that's a fantastic idea.
Could I get some more info on what you did to cobble the Sts? (I'm new, I hope I'm not infringing.) Also, I can't see the name of the person who spliced the Sts, sorry. I suppose I'll learn.
Also, I have a boat that I received for my 8th birthday, in the 50s, but it came with a Frog 150 Model Aero Engine as we used to call them then. Now they're NITRO!! 
I have extracted the engine, and, will put some kind of electric motor in probably next week. The poor old fella is a bit "tired" looking, so, next will be a full restore, to the best of my ability.
If I knew how to post photos, I'd show ya. 
However, as I get along with my projects, I'll let you know. Thanks a lot for your interest. That's very nice.
Neil.

[kiwimodeller]

Neil, could you please give details of the kits (over 1,5m) that you have found. I have used P & M V twins too and they are very good value for money and run well. I posted above about building a paddler with two single cylinder double acting oscillators and these are the single cylinder version of the P & M engine. I have dealt with P & M but also get good service and prices from John at The Steam Chest. The reason for using the singles is that I can set up an engine on each side of the stern similar to the originals. I was contemplating building from scratch as I had not seen any big kits so it would be good to get info on the ones you have found. To attach photos click on "Additional Options" just below the window in which you type your post. I have attached a photo of my 80" sidewheel paddler. Cheers, Ian.

[Neil]

Hi Ian,
I think I'm misleading you. It's been many years in OZ since Imperial was the go, but, the longest Riverboat that I know, (so far) is 48 inches. I'm sorry, but that's about a foot short of 1.5 metres. I'll let you know the model when I can find a better price than I see now. OK?

Now, as to other things, I have a lot of help from friends in America (one calls me OZ, I call him 'Merica, (a bit of fun)), but these guys really know Riverboat models. I can't tell you their names unfortunately, but, what I can get from them, with their ok, I will send on to you.

There are a couple of books that these blokes put me on to;
The Western Rivers STEAMBOAT CYCLOPAEDIUM,  and The Western Rivers ENGINEROOM CYCLOPAEDIUM. Both by Alan L. Bates. They are fantastic.

I could tell you where to buy them at the best price, but, I'm waiting for the "go-ahead" from the lady who sold them to me. I'll let you know if she can handle the potential rush.

I have sketches of engines for these models, and a bit more stuff, including tiny copper boilers that will withstand great pressure. Australian made, as it happens.

I am trying to attach a photo, (eventually, I'll get it right), but, I think it's too big. I tried to delete it but, no go.

I'll stop trying now, and get back to you tomorrow with other links/stuff.

Best of luck.

Neil

[tobyker]

Neil asked how I cobbled the 2 STs together. First you find a length of K&S brass tubing which is a close bearing fit on the crankshaft. Then you find a drill which matches to OD of the drill, and whack the drill through the engine standards, or even a reamer, if you are into real engineering - I've got a small one but I can't remember now if I used it. You then have to cut two thirds of the way through one standard from the cylinder side, then cut vertically upwards through the crankshaft hole and then cut horizontally through the last third. So you have a base with one third of the crankshaft bearing hole. Take the back third off the remains of the standard, and the front two thirds off the other engine. (In the case of mine I'd already messed the other engine about for an O guage  tram project).Then stick the tube through the holes with the cylinders at 90 degrees and cut and file until it all locks together. You can stick a wedge of spare brass in any huge gaps. Put a damp rag over the tops of the standards, toast the bearing area with a blowlamp and apply soft solder - you don't want to melt the solder which keeps the port drilling plugs in the top ends. Pictures worth any amount of words attached, as I've got it stripped to fit a reversing valve block. I extended the crankpin by hard soldering another bit of brass tube over the pin, with the pin cut off the other shaft in the tube, and filing all the brass off until I had a longer steel pin. It'sa pity ST don't make that twin any more - I think it's a nice little engine.

[Neil]

Hi Tobyker,
That's fantastic. Thanks a lot.
Neil.    

[kno3]

Where are you going to place the reversing valve?

[Neil]

That's too sophisticated for me to even contemplate.
Neil

[tobyker]

I've bought a reversing block as supplied for Mamod and MSS model rly locos. I've drilled out the port drillings on the engine so I have the option of feeding steam in at the side or the top or either, and I intend/hope to mount the block somewhere in space between the two top ends, possibly held by brass manifold pipes sweated into the block and standards. If that isn't rigid enough ( I think it will be, and that will enable me to reduce the mass of the block considerably, I got screws to fit into the mounting holes of the block and will have to make up some brackets.)The block only arrived in the post from Dreamsteam today, and I'm mainly contracted to SWMBO today sanding/staining floorboards and moving wardrobes. I will publish photos when i've worked it out and done it. I do hope I get all 4 pipes connected the right way round!

Note to Neil - a piercing saw is an excellent investment

[tobyker]

Cracked it on my lunch break - drill even more holes, this time in the back (spring side) of the standards - one set above the spring bosses, one set below and hang the block on edge off the back of the motor. Now to see how tight a bend those brass biro tubes will take!