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[Bradley]

Peter,
I will not make any comment except that I was trying to be helpful.  I appear to have upset you and that was never my intention so - nothing further to say.
Derek.   

[HS93 (RIP)]

Peter,
I will not make any comment except that I was trying to be helpful.  I appear to have upset you and that was never my intention so - nothing further to say.
Derek.   

sorry for Jumping ,

Peter

[UKJonathan]

Hi Greg,
             The pics I put on and the way I took them make the engine look almost touching the rear but it is not as near as it looks here is a better pic showing scale although taking pics seem to compress the size. Also I think I am going to go down the HPI route I think,
Jonathan

[Circlip]

This is a part of the PM I'm sending to you Jonathan, but putting it on here so that others may be able to see that it is in fact Stevensons that S/T show fitted to the "Old" Launch Twin. You will also notice that you haven't got the cylinder drain cocks fitted either, though how you would link them and operate whilst the boat is in the middle of the pond would require a REALLY powerful servo.

        http://www.stuartmodels.com/inprod_det.cfm/section/casting/mod_id/63

  It seems the original maker wanted to use this in a vessel opposed to haveing a "Bling Queen", as linking and operating Stevensons is not impossible, but is more difficult than a piston valve engine with a reversing lever. Yes they have been and are used, but sliding the quadrent over is wasted thirty feet away. Far from "Should have come with reversing gear fitted", if you look down the page on the second link, it clearly states "Items NOT supplied with the KIT" which again suggests the builder wanted to play rather than look.

     http://www.stuartmodels.com/pdfs/Twin-Launch-Parts-List.pdf

  T'ony problem with the boxes that Peter (NOT having a go) is suggesting is that it's a "Crash" box or looks to be, ie. no clutch, and Engaging it into reverse without slowing the engine although not TOTALLY detrimental will chuck a splash or two, just like has been said to criticise the reversable prop??

  Any road, scans will be on their way shortly.


   Regards  Ian.http://

[gondolier88]

Hi Circlip,

Just wondering about a couple of things you point out-

1st,

This is a part of the PM I'm sending to you Jonathan, but putting it on here so that others may be able to see that it is in fact Stevensons that S/T show fitted to the "Old" Launch Twin. You will also notice that you haven't got the cylinder drain cocks fitted either, though how you would link them and operate whilst the boat is in the middle of the pond would require a REALLY powerful servo.

Why would drain cocks require a really powerful servo? If oiled and eased they should turn with the slightest touch.

2nd,

  It seems the original maker wanted to use this in a vessel opposed to haveing a "Bling Queen", as linking and operating Stevensons is not impossible, but is more difficult than a piston valve engine with a reversing lever. Yes they have been and are used, but sliding the quadrent over is wasted thirty feet away. Far from "Should have come with reversing gear fitted", if you look down the page on the second link, it clearly states "Items NOT supplied with the KIT" which again suggests the builder wanted to play rather than look.

     http://www.stuartmodels.com/pdfs/Twin-Launch-Parts-List.pdf

It seems the original maker didn't have a clue to make a useable steam engine- good workmanship aside!!!!

The quadrant if fitted with a double quick threaded reversing wheel can be turned with a decent sail winch servo motor- who said it has to be lever controlled?

Lastly, it clearly states on the link you posted;

STUART TWIN LAUNCH PARTS LIST


8 (RG) 24201 ECCENTRIC SHEAVES CAST IRON 2
3 (RG) 24202 ECCENTRIC RODS GUNMETAL 4
18 (E) 24280 SLIDE VALVE GUNMETAL 2
9 (RG) 24203 SLIDER BRACKET GUNMETAL 1

MATERIALS NOT INCLUDED IN THE KIT


5 (RG), 12 (RG) MS140 DRAG LINKS, ANCHOR ROD BKT. MILD STEEL 1⁄4" sq x 3" 2
7 (RG) MS192 REVERSING LEVER MILD STEEL 3⁄8" x 5⁄8" x 5 1⁄2" 1
2 (RG) MS207 EXPANSION LINK MILD STEEL 1⁄8" x 1" x 2" 2
(RG) 24656 EXPANSION LINK PINS MILD STEEL 1⁄32" O WIRE 1
5 (E) SS225 VALVE RODS STAINLESS 1⁄8" O x 2 3⁄4" 2

Then also included in the kit are;

STUART TWIN LAUNCH FIXINGS LIST
.
PINS 25051 REVERSING LINK MILD STEEL 1⁄16" O x 1⁄2" 1
BOLTS 71703 ECCENTRIC RODS MILD STEEL 7BA x 3⁄8" 4
BOLTS 71707 CONNECTING ROD MILD STEEL 7BA x 5⁄8" 4
BOLTS 71707 ECCENTRIC STRAPS MILD STEEL 7BA x 5⁄8" 8
BOLTS 71708 DRAG LINKS MILD STEEL 7BA x 11⁄16" 4
NUTS 71755 ECCENTRIC STRAPS MILD STEEL 7BA 8
NUTS 71755 ECCENTRIC RODS MILD STEEL 7BA 4
NUTS 71755 DRAG LINKS MILD STEEL 7BA 4
CSK SCREWS 71787 SLIDER BRACKET MILD STEEL 7BA x 1⁄4" 8
GRUBCREWS 71825 ECCENTRIC SHEAVES MILD STEEL 7BA x 1⁄8" 2
GRUBCREWS 71825 SLIDER BRACKET MILD STEEL 7BA x 1⁄8" 2

Quite clearly you can see that most of the materials and fixings require ARE included in the kit, including most importantly, 4 off eccentric rods.

Greg

[flashtwo]

Hi,

I tried a couple of methods of drain valve operation on my Stuart D10.

The first method utilised the Stuart drain cocks, but with their handles modified to mate with a common linkage so that one servo would operate the four drain cocks at once. The problems I encountered were aligning the linkage with all four cocks for smooth operation and also the valves unscrewing from the cylinder if they were not perfectly aligned.

For the second method I made a sleeve valve with four inlets exhausting through a common stainless steel tube with the outlet at the end. The cylinder drain ports were then connected to the sleeve valve with 1/8th OD copper pipe. The valve spindle was linked to a cheap £7 servo.

This performed very satisfactory under remote control, but in practise I found I was only using it on the initial start up. As an experiment, I have blanked off the cylinder drains altogether and now just joggle the reversing gear to dump condensate on startup.

If you use servos on steam plant ensure there is sufficient linkage length between the hot parts and the servo to prevent the plastic gears from melting (it happened to me!).

For the reversing gear servo, I did resort to an expensive high torque servo with metal gears and a 2:1 ratio lever, because of the back reaction of the reversing gear as the eccentrics moved.

Ian G.

[Circlip]

I bow to your superior knowledge Gondolier, although as a double acting twin cylinder slide valve engine, I would have expected there to be 2 eccentric sheaves and also 2 slide valves included,      . There are far more bits pertaining to the reversing mechanism not included than you have shown, but hey, it's a moot point really despite them including a few extra nuts a bolts. Stuarts, including the original owner seem to sell reversing gear as an extra, so perhaps the extra bits in the kit are just like a supermarket "Loss Leader"??

  Hope all the bits got through Jonathan, you now have three avenues to look at.

  Your photo's Ian G are as interesting as ever, many thanks.


   Regards  Ian.

[UKJonathan]

Hi Ian and all,
                  first thing I have to do is thank you all for your input, and outlining my options. I will mull over them and I am quite sure I will come up with the right solution. The good thing is having all this knowledge, at ones finger tips to tap into is really helpful. I will keep the forum informed of my decision.
Jonathan