Mystery steam engine

[chris123]

The only thing critical are the ports and the valve edges.
Nothing else matters much.
.

Thanx green twin
I just make that he valve lies on properly on
The valveface centered and thats it
Chris

 

[GreenTwin]

Even if the port face is at an angle, the valve will still ride flat on it.
The valve should be able to float a bit on the rod, and not be attached tightly to the rod as far as movement away from and towards the port face.
This was how the old D-valves were able to automatically take up wear.
.

 

[Jasonb]

Well with the buckle design you do need it to be quite close to parallel as if the valve is tilted too much it will become tight in the buckle and won't be able to move relative to the face.

The hole position which we have been talking of is also quite critical on this as there is not a lot of clearance in the valve so it needs to be within say +/-0.005" or 0.13mm if the valve is to have some movement. To little and the valve will be held tight to the port face and will also make the valve rod bind. Too much and it won't make contact with the port face and you will just leak steam/air

 

[GreenTwin]

I think the metric/imperial thing is like Chevy/Ford.
You are either a "Chevy" person, or a "Ford" person, but you are not a little of both.
At the race track, there were Chevy, Ford, and Hemi folks, and there was a huge rivalry.
And they all thought their brand was the best, but well all know Chevy is best, but I must admit those Hemi's were hard to beat.

I have metric tools because the cars and tractors use metric fasteners, but I don't stock metric fasteners, and I never will.
Keeping up with one set of fasteners/taps/dies is plenty.

The building industry here still uses feet, inches, pounds (weight), etc.
It is very convenient to build around standard sized items, like 4x8 plywood, 2x4 studs, standard floor tiles sizes, plumbing pipe sizes, etc, etc.

If I lived in Europe, no doubt I would be a "Metric" person.
I think many here have rejected the metric system, because they don't think it is better, it is just different.
Machines and equipment here that are configured into assemblies seem to have gone metric.
Buildings and large sitework are not metric.

I think I am getting off-topic here.
.

 

[chris123]

Maybe
Bud you are right green twin
Chris

 

[Charles Lamont]

The hole position which we have been talking of is also quite critical on this as there is not a lot of clearance in the valve so it needs to be within say +/-0.005" or 0.13mm if the valve is to have some movement. To little and the valve will be held tight to the port face and will also make the valve rod bind. Too much and it won't make contact with the port face and you will just leak steam/air

In designing the valve I had to deal with the valve rod seemingly being very close to the portface. This is why the exhaust cavity is shallower in the middle of the width. Now we know different, the hole through the valve could be made larger, 8mm or even 9mm.

While a lot of stuff in the UK is genuinely metric, boards are still 8 x 4, they are just designated as 2440 x 1220.

 

[chris123]

In designing the valve I had to deal with the valve rod seemingly being very close to the portface. This is why the exhaust cavity is shallower in the middle of the width. Now we know different, the hole through the valve could be made larger, 8mm or even 9mm.

While a lot of stuff in the UK is genuinely metric, boards are still 8 x 4, they are just designated as 2440 x 1220.

Hi charles
I can make the hohle bigger
That means it wouldent matter if paralell or not
The buckle have to be accurate isnt it?
Chris

 

[chris123]

Hi charles
I can make the hohle bigger
That means it wouldent matter if paralell or not
The buckle have to be accurate isnt it?
Chris

I actually didnt drill that hohle yet
So u could change things if needed
Chris

 

[Charles Lamont]

That means it wouldent matter if paralell or not

Depends how far off it is. How much is the port face out of parallel to the valve spindle? Are you sure the valve spindle is vertical?