Need help troubleshooting - cylinder motion jittery
Hi, this is my first time using pneumatics so I don’t really know what I’m doing wrong. I’m running into some frustrating jitter on a pneumatic assembly setup and could use some hardware advice.
I’m using a 2-1/2” bore air cylinder with a 36” stroke to press a heavy part horizontally into a housing, but I can't get the extension to stay smooth. I’ve got a 4-way directional control valve and flow controls mounted on the exhausts for a meter-out configuration, all running on 120 psi shop air. It starts out fine, but as it nears the end of the stroke, it starts to lunge and jitter, which causes it to clash into the part I’m trying to move. I made sure to pre-load the cylinder before starting the motion. I also checked the cylinder for leaking piston seals, and it’s ok.
I can see the pressure on my regulator gauge dropping when the motion slows down and then spiking right as the cylinder jumps forward, making the whole process unreliable. I’m wondering what I should buy to actually stabilize this. Any suggestions on what hardware would fix this would be a huge help.