A little Throttle-Valve for my STUART #1

[dampfspieler]

Hi,

i have got a STUART #1 from a ebay UK. It was described as built at a high standard and should run well with compressed air. I have it checked and was like the Queen - "not amused". So i have it comprehensively overhauled.

I wanted a separate throttle-valve on the engine, and the design was inspired by the NAVY K because I find that absolutely fascinating.

It is a slide valve made from semi-finished products. During its construction, I chose some new solutions that I believe might be of interest to others as well.

Rendering

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The connections are as follows:
- Top: Steam from the boiler
- Bottom right: Steam to the engine (steam chest)
- Bottom left: Connection port for the cylinder lubrication oil trap

Dimensions

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Section through the assembly

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Dietrich

[Kelly Anderson]

Well done!

[dampfspieler]

Hi Kelly,

i'm glad you like it. I hope that applies to the now-finished valve as well.

This is what the valve face looks like. Thanks to the pointed shape, the steam can be metered more precisely at small valve openings, allowing for better control over the engine's operation.

the valve face with its special port before lapping

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The valve is mounted slightly differently than in the design, as it must be operated from the column side due to the engine's primary direction of rotation.

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A view of the engine's control side. The valve lever is in the closed position. The reversing lever is in the reverse position. For improved operability, it is now angled—a departure from the original design.

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Both levers can be locked in the desired position by means of a clamping mechanism.
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Dietrich

[TahoeSteam]

Gorgeous work, as always Dietrich. Thank you for sharing with us!

[dampfspieler]

Hi Wesley,

thank you.

Yesterday, I tested the newly built whistle valve under steam and checked that the steam whistle setup was correct. That was successful.
And since the boiler was already up and running, I also tested the throttle valve with steam. That worked very well, too.

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However, the test came to a premature end when the pressure piece of one of the safety valves unscrewed itself due to the vibrations caused by the escaping steam and flew off.


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Dietrich