Hi all,

I have an engine here for identification. Bought it recently (without any history) and according to my Internet research it is called a "trunk steam engine". As you can notice, it is not the usual configuration. It is a double acting engine with slide valves, but, rather than having piston rods, it has a more peculiar arrangement: the piston rods are actually wide tubes and the con rods run into these tubes.
The result is a very compact engine (the same size as an equivalent oscillator) but it is still having reasonably long con rods so it doesn't wear off prematurely.

The following parts (at least) are made from bronze castings: cylinders, valve chests, base, crankshaft frame, eccentrics, eccentric straps.

Here are the pictures:

2010-11-07 007 by -kno3-2, on Flickr


2010-11-07 001 - Copy by -kno3-2, on Flickr

1. Does anyone know who made the castings, or perhaps the engine?

2. As you can see in the picture with the yellow arrows, it is missing the valve rod crosshead on one side. This is a brass fork, I assume it has some sort of imperial thread.

Is anyone here with machining capabilities and suitable imperial thread cutters able to make me a new part (perhaps using the other one as a template)?
Please let me know here or via PM.

Thanks!

I'm sure I've seen this engine before, and I've been wracking my brains trying to think where!

I've searched and searched without luck, but I believe it was the engine used in a model paddle tug called Pilat.  I have no idea who designed it, but try searching for the tug and you might just hit on the engine....

The plans for Pilat were available from Model Boats magazine, but I'm not sure if the engine plans were available from the same source?

Regards
Eddy

Thank you for the information. I have only found this reference to a tugboat named Pilat: http://www.taubmansonline.com/MRBPILAT.htm
Unfortunately they don't show any pictures. I have e-mailed them, let's hope I can find out more.

Do you remember if you saw this or a similar engine in a publication or for real?

Attached is an image of the model of Pilat that I had a few years ago.... Electric powered. But this was the same as the model I saw the steam engine in.

I vaguely remember chatting to the owner of the steam powered one, and I'm certain that he said the engine was made from commercially available plans, and was designed specifically for Pilat.

Regards
Eddy

http://www.dreamstime.com/stock-images-old-red-tugboat-image5736464 ...has the same name kno3.......sorry but it is not a paddler.......Derek

Then we had another PILAT here on PD's......

quote author=Hankwilliams link=topic=4766.msg22924#msg22924 date=1251279766]
Your boat  now has the status of a live steam antique and technical model-monument, you should protect it in a good way to the future.
And why not make a steam up with pictures, the machinery seems functionable?

My first boat I`ve built 1966 in the age of 13, it was a tug named "Hamburg II" by Robbe.
However I was very interested in this years to make a live steam model, this was prevented throught the lack of experience, available steam engines and parts and least not last of money.

In 1968 I made my first plan built 1 : 50 scaled sternwheeler "Marieville", driven by electric.

Later there was a long break of model making until 1989, when I make the first live steam boat, the well known "Pilat", driven by an oscillator, which I mentioned a few days ago.

Quote from: Eddy Matthews on November 09, 2010, 08:21:08 PM
Attached is an image of the model of Pilat that I had a few years ago....

is that the one that was at 'paddler day 2008?'
http://www.paddleducks.co.uk/smf/index.php?action=gallery;sa=view;id=2605

Yes that's the one Mick - It's still in our club, so it still puts in an appearance... I should just clarify, that it's the model I used to own, which is electrically powered, NOT the steam one!

Regards
Eddy

Hi Eddy,

I`ve build my "Pilat" in 1989 and she is steam driven by a turned V-oscillator engine, bore 10 mm, stroke 20 mm. I turned the engine, so the shaft is above the engine frame, the position is approximately near  the shaft of the paddlewheels.
With a gear reduction of 1 : 3,5 power and speed are sufficiend.
Sorry, I`ve no photo in the moment. I had extendet the lenght of the boat from 140 to 150 cm. For my opinion, this gives a better proportion of the ship - the original "Pilat" lenght was about 65 m.
In 1 : 33 this would be a model of nearly 2 meters lenght - some difficultis about transport are to expect.

Tom

In the plans of "Pilat" also an oscillating engine, but direct driven with no gear reduction, is to see. It`s not a trunk engine and I don`t think, that the engine on the pics was used in "Pilat", because the paddlewheels seems too narrow.

But why not use for this model? It would be not very difficult, to alter the wheels to wider dimensions.

Tom

Thanks for the answers everyone. It looks like it is not the engine for the Pilat tugboat then?

Since it's made of castings, I thought someone might recognize them, but no luck so far on several forums.

Ant luck getting the missing part made?, if not I could probably help just send me a PM..

Stew

Thanks, I already have a kind person doing it for me.

I think a Trunk engine is also know as an oscillating engine. The only trunk engine I have ever seen is the non-steam replica on HMS Warrior at Portsmouth, which looks like an oscilating engine, like those on most of the Dresden paddle steamers, Gisela and Hjejlen, lying on its side to power the screw

No, in a trunk engine the cylinders are fixed. Oscillating engines are different beasts.