|roy entwistle||22/05/2019 09:15:52|
|1021 forum posts|
If it's brass, and it looks like it, do NOT use WD40, WD40 is not a penetrating oil. Use something like Plus Gas
|4601 forum posts|
I like it!
It's true the crank suggestion isn't convincing. A reason I suggested ornamental was because I can't imagine how a crank would communicate sensibly with whatever valve is inside. (Might be because I don't know enough about valve gear and there is a simple solution!) And ornamental doesn't fit well with the maker going to the trouble of drilling that large hole - surely it has purpose.
Hopper's suggestion of a mostly up down movement using collars to flip the valve is much better than any of my over-complicated musings. Something like the valve trip arrangement on James Watt's early engines perhaps. I'd love to know what's inside!
|Michael Gilligan||22/05/2019 09:35:33|
13827 forum posts
+1 for that
Plus Gas Formula A, in a good old-fashioned can, is effective and economical.
3657 forum posts
I'm thinking some kind of simple (yet cunning) rotary valve. Something like a piece of round bar inside a hole drilled in a solid block. The block has two small ports drilled right through it, each port connects to the cylinder above. Below, one port to the steam inlet pipe, the other to the exhaust. Two small holes drilled crossways through the round bar, at 90 degrees to each other, would allow through-flow through one port at a time. The round bar is rotated through 90 degrees by the "needle" and crank arm at the end of each stroke.
Or offset the ports slightly and file flats on the round bar to give finely tuneable valve timing and perhaps less than 90 degrees of rotation needed to make it work. My mental CAD abilities end about there. I need the back of a fag packet and a burnt match to take the concept any further.
3657 forum posts
Rotary valve shown here could be something like what's inside there *LINK*
|Michael Hudson 6||22/05/2019 13:08:03|
|22 forum posts|
A small update from me - have ordered some plus gas, have kept away from the wd40.. Very intrigued regarding the possible valve arrangement. I think I will try and talk to our vet and see if they will oblige with an X-Ray or two
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