Anyone know of a good intro to penumatics site. Want to know what the difference between 2 and 3 way valves, single acting and double action cylinders, etc.

I'm looking for some "beginners" info on this as well. Anyone.....anyone.....

Good questions, a 2 way valve is like a switch. Its on or off, actually open or closed. A 3 way valve can come in a couple of different layouts, but the most common and most useful for our purposes would be: Port 1-pressure from air supply[compserror or tank] Port 2-goes to device [cylinder] Port 3 goes to atmosphere.
In the normal or unenergized position the valve does not allow air to go past. When the valve is energized air is allowed to pass from port 1 thru port 2 to activate your device [cylinder]. When the valve is deactivated the valve closes off flow from port 1, and opening port 2[connected to cyl] to port 3 allowing air from cyl to escape.
this type works best for single acting cylinders, the kind with one port and are spring or gravity returned.
the other common type of 3 way is simular, but different. In the deenergized position it sends air to port 2 and in the energized position it sends air to port 3. this works on double acting cylinders and uses pressure to move the cylinder both directions.
Hope I haven't muddied up the situation too much...

rainy, any info is helpful......thanks

Well I never found one ! Rainy gave you some good info

Here is some of my experience as a total noob in pneumatics. 2005 was my first year to get something working and I was where you are in 2004 but out of time and not enough info to buy someting and have any clue to make it work.

The first one I got was a 2" Bore and 12 inch stroke double acting cylinder. The stroke is how far the cylinder moves. The cylinder has 2 ports and I also got a 4 way valve. This has 1 air input then 2 ports one to each of the cylinders connections and the 4th is the exhaust port for when the cylinder de-energizes. The valve I got was also 120V AC. The valves come in may different DC voltage ranges and 120V AC. When I first tried it with approx 30psi I was thinking the cylinder would "fly" up very fast but it was very smooth and when I removed ac from the valve it came back down very easy not too fast not too slow. The excess air comes out the exhaust port. Their are exhaust mufflers they screw in just like a normal air connector and the exhaust is baffled a little to cut down the noise.

I next got a 3 way valve with a single acting cylinder. A single acting pneumatic cylinder is "like a screen door opener" it has one air connection and a spring inside. So the valve has an air input and output for the cylinder and the exhaust port. Again I got a 120V AC valve.

We have 3 local pnuematics suppliers (yellow pages) and only one of them was helpfull to myself. They asked what I needed it for and I told them I was trying to make something for Halloween. The guy said he had several people doing the same type of thing. This guy was "very helpfull" to me and for that, I bought my stuff from him and paid more than EBAY but the help / support / service was worth it and keeping the $$ in our local economy is more important to me. This was late November 05. Also some of the local pro haunts buy from the same place. Let us know if you have more questions

RU

I have a question: Am I right that the valve is triggered when power is applied? How do you trigger it? Event controller, Stamp, timer, switch mat???

I have used both event timers, mat switches and PLC modules[way too complicated]

I found this site. Haven't had time to read through it but the pictures look good:

http://wolfstone.halloweenhost.com/T...aticIntro.html

i liked this one
http://www.scaryguys.com/aircyl.htm

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Yep DoD, thats a good one too. Here's another one from the FCG guys:

http://www.phantasmechanics.com/air/index.html