Author Topic: SS Xantho John Penn trunk engine  (Read 16852 times)

Offline Pedro

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SS Xantho John Penn trunk engine
« on: January 15, 2014, 12:24:45 AM »
Hello there. I'm planning a build of a John Penn trunk engine, in particular the one from the SS Xantho in Oz. I've approached the WA museum but so far no reply. There are a number of Victorian engravings of larger engines which are detailed enough to do a good pastiche, but I was wondering if anyone has any info for this one. Apparantly drawings were made and a model built, but I can only find the one reference online.
It is a particularly iconic engine, since it was made for one of two batches- (the other by Maudslay) built for gunboats in the Crimean War. Innovations included high pressure working with no condenser, standardised Whitworth threads, and rudimentary mass production. So far the only info I have is 21" bore, 12" stroke, 11" trunk, a few photos of the rusty original, and a contemporary engraving of a much larger ship engine, though of similar style. Any ideas? 

Online steamer

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Re: SS Xantho John Penn trunk engine
« Reply #1 on: January 15, 2014, 01:09:59 AM »
I assume the engine still exists and is located at WA museum?....is visiting that museum an option?

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
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Online steamer

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Re: SS Xantho John Penn trunk engine
« Reply #2 on: January 15, 2014, 01:10:55 AM »
Oh and feel free to tell us about yourself, and any other models that you've made.   8)

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline b.lindsey

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Re: SS Xantho John Penn trunk engine
« Reply #3 on: January 15, 2014, 01:12:58 AM »
Hi Pedro, Dave beat me to it...it would help to know where you are from also, and a brief introduction would be much appreciated also. In the meantime, welcome to MEM and best of luck on your search for information on this engine.

Bill

Offline Pedro

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Re: SS Xantho John Penn trunk engine
« Reply #4 on: January 15, 2014, 02:08:22 AM »
Sorry guys, I'll do a proper intro tomorrow, it's late here in UK. Sadly, I can't afford to go to Oz. Thanks for the interest. Catch you later.

Online steamer

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Re: SS Xantho John Penn trunk engine
« Reply #5 on: January 15, 2014, 02:11:32 AM »
That may or may not be a problem, we may have some members there that can help.

Have a good night, talk to you tomorrow.

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline peatoluser

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Re: SS Xantho John Penn trunk engine
« Reply #6 on: January 16, 2014, 04:24:52 PM »
Perhaps not what you want to hear. I've often looked for drawings of horizontal marine engines but they seem to be thin on the ground.
the best I've seen are in a book 'modern marine compound engines being a supplement to modern marine engines ' by N.P. Burgh. published, I think in the mid 1870's.
If I remember correctly, there was a couple of horizontal engines drawn , 1/12 scale . quite detailed general arrangements with sectional views.
Don't get a print on demand version. the fold outs aren't folded out in the copying. Reference or university libraries might have a copy.
obviously they are compound engines with all the trappings of condensers , air pumps etc.
Also, in the science museum, London, there are some fine model marine engines including a horizontal trunk engine on display . well there was last time I went many years ago, but museums do change the odd exhibit.
Perhaps are friends in Oz might be able to help? specially after normal service has been resumed in the ashes!

regards

peter

PatJ

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Re: SS Xantho John Penn trunk engine
« Reply #7 on: January 16, 2014, 04:36:21 PM »
Here is a photo of the engine:
http://www.gracesguide.co.uk/File:Xantho01.jpg

and here is a link to a simulation of the ironclad Monadnock trunk engine (similar to the Monitor engine).

It would not be difficult to modify the geometry for the Xantho engine (for some).
The photo provides sufficient information to design the engine.


PatJ

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« Last Edit: January 16, 2014, 06:39:51 PM by PatJ »

PatJ

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Re: SS Xantho John Penn trunk engine
« Reply #10 on: January 16, 2014, 06:50:34 PM »
This engine would not be that difficult to model with the information available.

Looking at the photo below, you can see that the exhaust pipes are the "Y" configuration, and the steam pipes are the ones going into the steam chest horizontally on either side of the engine.

http://www.gracesguide.co.uk/File:Xantho01.jpg

The bar across the back top of the engine would most likely be for the reversing gear.
I am assuming a reversing engine since there are two eccentrics per cylinder, although the Monitor engine also had two eccentrics per engine but used those for a double piggyback (what is the correct term for this type of vavle, Myers?) slide valve, and a clever reverse mechanism that was non-standard.

All you would have to do is model one cylinder and one of the three frame sections (in 3D modeling), and then copy the remaining items, since they are copies.

From the literature, it sounds like a standard D-valve.

The steam chests were a bit odd in shape, with an extension upward to connect to the steam pipe.
This extension would make for a weak casting, and a complicated casting too; not a good idea, but to be historically accurate, that is how it was done.

I wonder if it could have had a Stephenson's link?

Somebody down under needs to go by the museum and get some good photos of the model.

Pat J

PatJ

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Re: SS Xantho John Penn trunk engine
« Reply #11 on: January 16, 2014, 08:48:39 PM »
After a great deal of digging around, I found this excerpt from a thesis presented for the Degree of Masters of Philosophy, Murdock University, 1989, titled:
"Charles Edward Broadhurst (1826-1905), a remarkable nineteenth century failure".

This engine could absoulutely be modeled and built using the limited information available, especially this photo.

I was correct, the engine used a Stephenson's type links and was reversible via the rod across the top of the engine that has the reach rods (correct term)? on it.

Who is going to get started on the 3D model for this engine?

Pat J

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Re: SS Xantho John Penn trunk engine
« Reply #12 on: January 16, 2014, 08:51:06 PM »
I have a very good book on the history of the US steam navy up through WW1.   I know there are quite a few cuts of trunk guided engines like that, I can scan them.....if you're patient..... :ShakeHead:


Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!

Offline Jasonb

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Re: SS Xantho John Penn trunk engine
« Reply #13 on: January 16, 2014, 08:51:52 PM »
What you mean you haven't started drawing it yet Pat :LittleDevil:

PatJ

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Re: SS Xantho John Penn trunk engine
« Reply #14 on: January 16, 2014, 09:02:44 PM »
Ok, I am foaming at the mouth over the info I found on the Xantho engine.

Not like I need another engine to model, but there is plenty of info to do this one.

Gosh, and I am in the middle of a work project right now, so I can't start on it yet.

Well I will decide next week once my work project goes out.

This would be a nice one to model/make.

I guess I would make the bore about 3" to keep the parts from getting too figgity (or maybe 2.5" bore).

« Last Edit: January 16, 2014, 09:24:34 PM by PatJ »