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Cat966c
01-20-2016, 03:52 PM
Hey all; was just wondering if someone could explain to me in lay man terms how a hydraulic valve works. I'm going to try to make a budget one down the road and I think I have all of it figured out except the valve part aka the thing that governs the back and forwards motion.

Finster
01-20-2016, 05:01 PM
There are a lot of different types of valves out there so its hard to answer your question simply, but here are a couple videos which show valves.

Close center spool valve
https://www.youtube.com/watch?v=vY_bguSNgSc

Rotary valve (not the best animation but might help)
https://www.youtube.com/watch?v=th_eOkTh9yE

Basically you are opening one port exit to the pressure from the pump while connecting the other port to the return to the tank. A spool valve does this by sliding the 'lands' (bigger parts) back and forth and a rotary valve does it by turning the cutouts so they line up with the ports. Hope this helps...

Cat966c
01-20-2016, 05:21 PM
Yeah. Im kinda stumped about when one port opens to push it forward, what kind of wiring makes the other port close, or go back to the return tank

Supermario
01-20-2016, 06:01 PM
I remember seeing a control valve sliced in half to show exactly how porting looks inside when I was in trade school.
Do you have a college or trade school type place in your neighbourhood? I'm sure they'd have some cut open components to help show how they work?

RCP57
01-20-2016, 07:07 PM
My stuff use plug type valves. I went to the local Princess Auto and bought a really cheap 3 way air valve and took it apart so that I could see it first hand. I was bad after that and took it back to the store...https://www.google.ca/url?sa=t&rct=j&q=&esrc=s&source=web&cd=6&cad=rja&uact=8&ved=0ahUKEwjr7vWvwLnKAhUE3GMKHW7IA-4QFghEMAU&url=http%3A%2F%2Fwww.princessauto.com%2Fen%2Fdetai l%2Fpneumatic-rotary-control-valve%2FA-p8190480e&usg=AFQjCNE_HRglf5N1AxGFQAEhZE-c4d_Y0g&sig2=ShsCp2oBgEHpI6_JXYupyw I'm sure you could find something like this at any similar store.

Supermario
01-20-2016, 11:04 PM
:o. My bad. For some reason I thought you were asking about real scale hyd valves:rolleyes: on a RC site..:confused: what was I thinking:lol:

Cat966c
01-20-2016, 11:30 PM
Haha, no prob! (: We don't have any trade schools very close to here, but I'll look around

Cat966c
01-25-2016, 10:37 PM
Bump?

RCP57
01-25-2016, 11:59 PM
Do a YouTube search. Plenty of videos explaining how they function.

Rimrock
01-26-2016, 08:57 AM
One have the 'axial slide' valve, the most common in 1:1, and the 'rotate valve', most common in scale modelling. To find out how the valve are put together is not that big problem (google/youtube) but to make one at home that holds on to any pressure is the challenge. To have good success, miniature O-rings often are to be added in the correct locations in the valve, which most of the German miniature hydraulic producers have realized, but the chineese are struggling a bit more, as some extra O-rings will ad some cent's to the production cost it seams..or whatever. Maggom newest valveblocks and pumps seams to work okay, at a relative reasonable price..as your possible 'plan B'

Cat966c
01-26-2016, 06:01 PM
Cool. Thanks! (:

Cat966c
01-26-2016, 09:50 PM
Finster: OH MY GOD--that's SO genius!!!
Thank you!!!