Model Boat Mayhem

The Shipyard ( Dry Dock ): Builds & Questions => Steam => Topic started by: kno3 on May 04, 2010, 08:23:13 pm

Title: Stuart V-twin steam engine
Post by: kno3 on May 04, 2010, 08:23:13 pm

Hi all! I have bought this sorry little steam engine. The iron parts are rusty, but it turns well on compressed air. Anyone know who could have made it? Seems to me that there's a certain resemblance to Stuart.

(http://farm5.static.flickr.com/4061/4579276576_b146fe31cc.jpg)

(http://farm5.static.flickr.com/4016/4579276856_08479a0f0e.jpg)

I'm planning to strip it, remove the rust and paint and then restore it. It should then make itself useful in a marine steam plant (if the restoration is successful).

Title: Re: Stuart V-twin steam engine
Post by: kno3 on May 05, 2010, 10:50:47 am

Since nobody here seems to know, I've found out in the meantime over on the http://modelsteam.myfreeforum.org that it is a Stuart engine.

Title: Re: Stuart V-twin steam engine
Post by: vintagent on June 04, 2010, 12:36:09 pm

It bears many similarities to the W.J.Hughes design for a single in Geoffrey Deason's Model Boat Book, from which I've pinched elements to make a 120 degree Vee twin for a very shallow boat to keep the weight low.
Nice little engine and should be a good starter, being double acting.

Good Luck,Regards,
Vintagent

Title: Re: Stuart V-twin steam engine
Post by: kno3 on June 04, 2010, 02:01:18 pm

Thanks for the reply. I have found out what it is:a Stuart v-twin, older model (their current one has the more usual steam valve, with a flat disc).

I have decided to restore it, so I have disassembled the engine and removed the old paint from the castings. The brass parts were cleaned chemically, to be polished later.
(http://farm4.static.flickr.com/3306/4591154675_dae6c3ed8b.jpg)

Preparing for new paint:
(http://farm5.static.flickr.com/4069/4591154809_6fd4f5a8cf.jpg)
I used a small file (shown in the background) to cut the masking tape in the required shape.

That's what it looks after the first coat of primer:
(http://farm5.static.flickr.com/4067/4591154917_c8eb7168cd.jpg)

Title: Re: Stuart V-twin steam engine
Post by: kno3 on June 04, 2010, 03:23:48 pm

I've painted the castings green.
(http://farm4.static.flickr.com/3417/4592807692_909d869087.jpg)

And polished the cylinder port faces etc.
(http://farm2.static.flickr.com/1270/4592807502_750cb8e00d.jpg)

Title: Re: Stuart V-twin steam engine
Post by: kno3 on June 04, 2010, 03:25:11 pm

Restoration finished. I've had new pistons with o-rings and new piston rods made, because the old pistons had no piston rings (just tiny grooves). The old piston robs were also a bit rusty.
Now the Stuart runs very well and has excellent compression (it's very hard to turn it by hand with the valve closed, yet it runs on low pressure very smooth).
(http://farm5.static.flickr.com/4019/4657326166_013d48ebc9.jpg)

(http://farm5.static.flickr.com/4045/4656704805_8714120073.jpg)

(http://farm5.static.flickr.com/4026/4656705107_e83c6a4c3e.jpg)

Title: Re: Stuart V-twin steam engine
Post by: vintagent on June 04, 2010, 05:25:19 pm

Nice job!

I take it the bit through the middle is some kind of regulator?
Regards,
Vintagent

Title: Re: Stuart V-twin steam engine
Post by: kno3 on June 05, 2010, 08:57:56 am

Thanks. That is indeed a reverse valve/speed regulator.

Title: Re: Stuart V-twin steam engine
Post by: vintagent on June 05, 2010, 10:27:30 am

Ah, now that's something I haven't seen on any drawings I have for simple steam plants.

Any ideas?

Regards,
Vintagent

Title: Re: Stuart V-twin steam engine
Post by: kno3 on June 19, 2010, 10:43:22 pm

Got to work on a new steam plant for this engine these days. It is going to be a pretty light and compact unit, to fit a 55 cm boat.

First I made a base, folded from aluminium sheet:
(http://farm5.static.flickr.com/4053/4714788153_9f906f08cf.jpg)

Preparing bits for the superheater, steam pipes and condenser:
(http://farm5.static.flickr.com/4071/4714788303_197daec399.jpg)

Condenser soldered but not finished:
(http://farm5.static.flickr.com/4028/4714788427_29585f9026.jpg)

Condenser finished, with superheater and steam pipes:
(http://farm5.static.flickr.com/4022/4714788537_14ca784d3e.jpg)

Preparing boiler fittings and condenser for painting:
(http://farm5.static.flickr.com/4068/4715429946_66f6c1d8a8.jpg)

Title: Re: Stuart V-twin steam engine
Post by: Circlip on June 20, 2010, 09:57:51 am

Given the number of rebuilds that you do Kno3, have you thought about obtaining a cheap hobby version "Sand " blasting gun?. I say this due to the condenser housing being Brass. Paint gets a much better "Grab" on metals if they have a keying surface rather than smooth. "Soft" paints are also more resilliant to a slight knock rather than Hard ones.

  Regards  Ian.

Title: Re: Stuart V-twin steam engine
Post by: kno3 on June 20, 2010, 10:08:38 am

Where would I get a cheap sandblasting unit? I like the sand blasted finish too and I know if improves paint adhesion, so I could have good use for it.

Title: Re: Stuart V-twin steam engine
Post by: kno3 on June 20, 2010, 10:14:03 am

Here's the finished steam plant:
(http://farm5.static.flickr.com/4052/4715476100_989d6a72ab.jpg)

(http://farm5.static.flickr.com/4063/4714834813_3759e532c0.jpg)

(http://farm5.static.flickr.com/4029/4714834427_e68472dc54.jpg)

Title: Re: Stuart V-twin steam engine
Post by: Bernhard on June 20, 2010, 10:26:13 am

Hi........LOOKS SUPER DUPER...great job you have don again :-)).........any video of it running,,,,,,,,,


Regards Bernhard

Title: Re: Stuart V-twin steam engine
Post by: Circlip on June 20, 2010, 10:30:36 am

America has "Harbour Freight", Britain has "Machine Mart" do you have similar? The "Cheap" blasting guns are basically a paint spray gun with a fine sand container. You're never going to get the same quality as using a "Propper" blast cabinet, but can you justify the cost of a proffesional set up? Various destructions on sites can give details to make a home cabinet, just a matter of scale.

  Finished plant looks superb, strange how different lighting changes the shade of Green from your original Photos, Ahh, the power of the digital age.

  Regards  Ian.

Title: Re: Stuart V-twin steam engine
Post by: HS93 (RIP) on June 20, 2010, 01:55:24 pm

I have one of these it is good on small parts but you need to make a box to spray in to and whee goggles and a mask


http://www.rdgtools.co.uk/acatalog/AIR_BRUSHES_.html

Peter

Title: Re: Stuart V-twin steam engine
Post by: kno3 on June 20, 2010, 03:25:59 pm

Thanks for the info.

Here's a video of the new steam plant running:

http://www.youtube.com/watch?v=jUAejWFcbw4

Title: Re: Stuart V-twin steam engine
Post by: vintagent on June 20, 2010, 05:48:25 pm

Very nice job kno3,
are there any drawings kicking around for steam valves that do the forward and reverse thing?

Regards,
Vintagent

Title: Re: Stuart V-twin steam engine
Post by: kno3 on June 20, 2010, 09:03:21 pm

I have a couple of drawings, but not of the valve used in my engine. Send me an e-mail and I'll send you the drawings.
You could also get them ready made.

Title: Re: Stuart V-twin steam engine
Post by: benjaml1 on June 20, 2010, 11:23:57 pm

Quote from: kno3 on June 20, 2010, 10:14:03 am

Here's the finished steam plant:

Looks lovely.....  :-))

Title: Re: Stuart V-twin steam engine
Post by: kiwimodeller on June 21, 2010, 10:38:58 am

I got a forward/reverse/throttle valve from the train people at Dream Steam [email protected]. Reasonably priced and it arrived on the other side of the world in just a few days. Hope this helps, Ian.

Title: Re: Stuart V-twin steam engine
Post by: kno3 on June 21, 2010, 03:04:24 pm

Somehow the images I had posted of the finished plant disappeared. Sorrry for that. Here they are again:

(http://farm5.static.flickr.com/4052/4715476100_989d6a72ab.jpg)

(http://farm5.static.flickr.com/4063/4714834813_3759e532c0.jpg)

(http://farm5.static.flickr.com/4029/4714834427_e68472dc54.jpg)

Video: http://www.youtube.com/watch?v=jUAejWFcbw4

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Title: Re: Stuart V-twin steam engine
Post by: Martin (Admin) on June 21, 2010, 06:05:56 pm

Topic renamed on request.  :-)

Title: Re: Stuart V-twin steam engine
Post by: gamma on February 17, 2011, 11:33:39 pm

I have recently bought in e bay an engine very similar to yours, kno; they sold me as a Stuart twin engine but when I compare with yours, I find some differences...are they different versions of the same engine?

(http://i378.photobucket.com/albums/oo225/gamma_mi/varie/P1040335.jpg)

(http://i378.photobucket.com/albums/oo225/gamma_mi/varie/P1040336.jpg)

Title: Re: Stuart V-twin steam engine
Post by: HS93 (RIP) on February 17, 2011, 11:45:13 pm

Yep that's a Stuart

Peter

Title: Re: Stuart V-twin steam engine
Post by: kno3 on February 18, 2011, 04:35:32 pm

@Gamma: You have the current version of the Stuart oscillating v-twin, same as the one seen on the Stuart website: http://www.stuartmodels.com/inprod_det.cfm/section/casting/mod_id/89

Mine is a much older version (can't tell how old though), the body casting and the reverse valve are quite different.