So my team is putting pneumatics into use this year for the first team, seeing how we’re a 2nd year team. For our wings, we have a solid mounting point on the non firing side of the solenoid, that allows the solenoid to pivot. On the firing end of the solenoid, right now we have one zip tie on the solenoid linked through a zip tie on the wing itself. This allows us to extend, but often give caught together and gets stuck. I thought a free(ish) mounting point on the firing end was the only option because when I tested a rigid attachment on that end, that still allowed pivoting, I found that the arm that fires from inside the solenoid rotated slightly and messed up the whole system. Are the solenoid firing arms supposed to rotate slightly? We have brand new pneumatic systems and didn’t know if this was intentional, or a defect. Also what is your teams mounting idea in this spot, if you care to share. I attached a diagram of the point I’m referring to. The blue is the wing itself, the black box at the top of the screen is the bot, the red is the solenoid, and the green circle is the joint I’m referring to.
The piston rods in standard air cylinders are free to rotate. Industrially, it’s possible to purchase special “non rotating” air cylinders, but they are specialized and more expensive.
The VEX air cylinders are small and the piston rods can be bent if the cylinder is abused. The best way to install an air cylinder is such that there is no possible of “bending” in the cylinder assembly, so there should be a free pivot on both ends of the cylinder. The rest of the mechanism should have whatever appropriate hinges or pivots are needed so the cylinder can do its work by freely extending and retracting. (On large industrial system, with cylinder bores in excess of 3 or more inches, sometimes a rigid mount is used but still care is taken in the design to minimize side-loading of the piston rod, because the nose-end seal can be damaged). For some additional information about pneumatic cylinders, here’s a useful article from a cylinder manufacturer: Pneumatic Cylinder: What Is It? How Does It Work? Types Of
A great way to pivot mount the moving end of the pneumatics is to put the end through the axle hole of a collar then you can put a screw in the grub screw hole.
If the screw also goes through the thing you want to move it can pivot in the screw to remove any side loading.
You can secure the collar using the 2 nuts supplied, one on each side of the collar as well as the screw. But don’t use too much force on the screw as this can damage the threads on the piston.
