What The Dealio? (...Just said it to get everyone's attention)

All right, I’m a member of one of those newbie teams and we were working on pneumatics. We followed the diagram FIRST provided, made a few modifications to suit 2 cylinders using two double solenoid valves, but nothing to screw things up or go against the example. Our problems…/questions are:

  1. When everything is connected, the max each of our meters read is 40 psi, but if we take one of the solenoids out of the picture, they get to 65 psi. We’ve run tests without the pistons attatched and the same thing happens.

  2. When our pressure rises we noticed that it rises fairly slowly in all cases… It takes about 15 to 20 seconds for it to reach its maximum (40 or 60).

  3. Should the main regulator read the same as the meter on the tank or should the tank read 120 while the regulator reads 60?

We ran a couple of tests and found out that the regulators, tanks, and compressor work fine. The tanks get to 120 without the regulators and 60 to 65 with the regulators and one solenoid and cylinder. We’d really appreaciate it if any of you guys could help us with all or at least one of our problems.

Thanks a lot and keep it on the real tip …Lowers head in shame

–Rusty Shackleford

Are you sure the regulator is not in backwards? There should be an arrow on it that tells you which way air is meant to flow.

The regulator’s downstream side will allow air from the high pressure source (your tanks) to enter the regulated low pressure portion when the pressure there drops below the set pressure, in our case, 60 factory set psi.

When the low pressure rises above the 60 psi, the regulator dumps air to the outside until it gets back down to 60 psi. This would occur if your piston sticks out the front of your robot as you crash into the diamond plate wall. It would also happen if you put higher pressure onto the downstream ports. (A “releiving” regulator)

If the flow markings on the reg are hard to see, read the manual to make sure you have the one hi-pressure port receiving the air. The other ports are all low pressure from the same part of the reg.


One other item to check: all those lovely push-in connections, and those lovely teflon-wrapped brass fittings. Check for leaks with soapy water (a galss of water with a squirt or two of dish detergent, works well, applied to the outside of each joint.

Thanks you guys, but we realized the problem was with that extra gasket for the double solenoids…it was causing the exhaust ports to let out a lot of air. Thanks a lot for your help though.

–Rusty Shackleford

*Originally posted by Rusty S. *
**The tanks get to 120 without the regulators and 60 to 65 with the regulators… **

One more tip - you are allowed to put the regulator downstream of the accumulators. This should give you better performance by way of increasing the number of times you can cycle the pneumatics w/o recharging the tanks, and keeping the output pressure more constant as you cycle them.

Have you checked for leaks?