Modified D-valve dimensions from print

[Builder01]

Although steam is pressing on the plate and slide valve, the steam port has steam at chest pressure that is very close to the exhaust port. It would only leak when the steam port is uncovered. Gasket sealer would minimize or eliminate leakage altogether. This would be the area I would be concerned about. Perhaps it is never a problem. Otherwise, it seems the plate is a good solution to bring the cylinder ports back into alignment with the drawing.

David

[Dick_Morris]

Just thinking - I I were to use the "sandwich" with the steam chest holding the plate in place I might use a couple of taper pins or tight fitting rust proof pins to ensure that the plate would return to the same location if it moved when the steam chests have to be removed.

[Builder01]

A potential problem with taper pins for alignment, is that, unless the holes for the pins are through holes, it would not be possible to remove the pins. I suppose you could drill and tap them, but, this makes it unnecessarily complicated. If you keep the clearance for the steam chest fasteners tight, these will keep the plate in alignment. My steam chests have 15 screws holding them to the cylinder blocks. The clearance holes are all very tight, movement is unlikely.

David

[blff cty lcmtv wrks]

builder 01--david
to answer your question, how do you hold the ss plate to the valve face? the ss plate is held down by the screws what holds the steam chest and cover to the cylinder block. I don't think that there will be any movement of the three pieces. there are a total of 14 8-32 screws holding it all together. in my case these are socket head ss screws. in addition, there are two #6 ss socket head screws holding the chest and the valve plate to the cylinder block. I put them in the front left and the back right of the cylinder block. their only purpose is to hold down the steam chest and valve plate and immobilize it so that you can remove the cover without having all the rest to slide around. makes valve setting easier.

your next question states that you understand where, but not how said valve plate is attached. I think I answered that in my reply to your first question. you state that because the area between the exhaust and steam ports is small, steam leakage could occur. keep in mind that this is ss plate that is one eighth inch thick. it should not distort due to pressure. if anything, incoming steam pressure should push the ss plate tighter to the valve face on the cylinder block and provide a better seal. if you machine a super smooth finish to the mating surfaces of the ss plate and the valve surface on the cylinder block, you should not get any leakage between ports. (I have built three cylinder blocks utilizing this method of construction, and so far, I have not heard any negative feedback from the owners of said engines.). just to be on the safe side, I will smear a coat of Permatex on the mating surfaces of the ss plate and the valve face of the cylinder block. then stick it all together.

thank you
bigc

[Builder01]

I understand your explanation of what is going on, thank you so much. I understand the plate is held in position by the steam chest and it's screws. I was just curious about why steam going into one of the steam ports would not go sideways to the exhaust port, by traveling between the plate and the cylinder block. Steam has a way of leaking through the most unlikely places. If Permatex does the job, that certainly is a simple solution. This seems like a simple way to bring the port positions back into alignment with the drawing.

David