Clyinder Cocks for the LE American

[Pipescs]

Continuing to make improvements to Kombrink's American.

Having worked on the piping, pumps and injector last year, I am starting to feel more comfortable running the engine.

This years projects have been adding a brake car behind the engine and adding cylinder cocks.

Larry's original cocks were spring loaded valves that I believe he meant to vent the condensate at the beginning of the run. Trouble is they did not work (springs may be too strong) and you always had water and oil shooting out the stack when you left the firing bay. People do not seem to enjoy getting sprayed with hot water like you would think.

The cylinder cocks I have been installing are from Blackgates Engineering located in England.

http://www.blackgates.co.uk/

I have dealt with them a few times in the past and they are very pleasant to work with. The cost of shipping from England is not bad when you are talking about something this size.

I ordered two sets as I am sure they will be damaged in the future.

They were not a fit out of the box for me. They offer the cocks in six or so different sizes. These are the 1/4x40 thread size. My engine has 1/4x28 threads. I originally looked at turning the original threads off the cocks and pressing on a collar with the correct thread. Turned out it was easy to use a thread chaser and then a die to force the brass to a 28 pitch.

When I ordered the cocks I also ordered a set of copper shim washers used to align the valves when snugged up. For any further unenlightened, I found there are two left valves and two right valves in the set.

[Pipescs]

The price on the Cylinder Cocks was 27 Pounds by the way. I believe with shipping the valves came in at $50.00.

After mounting them I started looking at various ways to run the linkages back to the cab. Realizing the American is Stand way off scale, I just started at the front and worked my way to the cab.

The design kept changing to fit the frame and I used Solidworks Student Version and a Creality 3D Printer to make test pieces until I had a working model. This took quite a few runs on the plastic parts until I had something that looked to work reliably.

The main piece was the mount for the bell cranks carrying the motion down to the cross shaft. As I was not wanting to add any new holes to the American, It is mounted using the existing frame crossmember bolts.

Once the project worked in plastic, I started making parts in brass and steel.

As an Interim, I have carried the actuating rod out the back of the cab. I am going to machine a brass know to actuate it. In for closed and out for open. Travel is about one inch. The plan is for a lever in the cab floor down to the rod

As a test, I took out the valve chest plugs and pumped the cylinders full of WD-40. With the engine raised off the test track I was able to rotate the drivers while opening and closing the cocks. Works as I had hoped. Steam test will have to wait a little while when the track opens back up.

Everything is now back out of the engine for cleaning and painting.

[gwrdriver]

Nice job, Charlie, clever solution.

[DianneB]

Nice job Charlie!
I like mechanical drains but couldn't figure an un-complicated way to get the linkage back to the cab.
It looks like your drains are further from the ends of the cylinders than mine. I have VERY little clearance between the pilot wheels and the drains in a curve!

[Pontiacguy1]

that looks really nice. I think you might have damage if you derail and the lead truck flips around. It'll probably take out your linkage. That's the only issue that I could see with it at all. Sometimes simple is better. Do they vent straight down or do they have a side-discharge that I'm not seeing?

[Pipescs]

They vent straight down. I am thinking of making a small fitting to go over the end that is drilled for a side exhaust.

[Fender]

Charlie, a suggestion: if you were to get some rectangular section bar stock, say 3/8 x 1/2, and bolt that to the underside of the cylinders (flat side against the cylinder) into the cylinder drain holes, then mount the cylinder cocks on the bar pointing outwards, they would not hang down as low. You’d have to cross-drill the bolts and the bar for the steam passages. I know, hard to visualize without a sketch.

[Pipescs]

They actually do not stick down any farther than the ones I am replacing.

Larry's spring loaded ones were made from Hex Stock. with a ball and a spring to seat against the pressure.

I never actually saw them work.

Where the problem may arise in a derail is in the linkage arm running under the frame.

From under the track shows the spacing a little better.

I ended up make the rod knob out of brass. I had thought I would do a lever inside the cab. Not such a good idea though as there is little enough room in there now to get your fingers into it when you need to.

In is closed, out is open.

[gwrdriver]

I am thinking of making a small fitting to go over the end that is drilled for a side exhaust.

Charlie,
Seeing as how these are British-made and all such drain cocks are designed to have tube extensions which divert the exhaust forward (or wherever needed) I would bend up a set of tight L's in copper tube (K&S or capillary) and solder them in. In the UK drain tubes are often long (for various reasons) but short and tight would do it for you. The photo doesn't exactly represent your setup but you get the picture.
I'm not a pessimist, and hope for the best, but if you were to go this route it would probably be prudent to make up an extra set or two while you're tooled up for it.

[Fred_V]

I have a CAD drawing for a similar drain that I used on my Chloe. If anyone wants it send me a PM.