Pneumatic actuator - making the end plates

Final assembly:
Quick tidy up of the assembly before looking at making the end plates. For one thing I need some groove to accommodate the spring which is 14mm long when solid. Also, I don't need an o-ring on the rod end of the cylinder, so there's no point making life difficult and risking tool breakages by machining an o-ring groove there.

I've even added the air inlet which is 1/8" BSPP.

Let's do some CAM now:

Bottom plate

 Top plate

....and make some swarf:

After drilling the 5 holes in the bottom plate, I had to do some "other stuff" which required powering down. So I had to pick up the coordinates again. 

With this probing operation you need to have confidence that your machine isn't going to go doolally and rip the tip off the probe....

Let's go. 4mm carbide end mill at 5000rpm.

Looks reasonable but there's something not quite right here. For one thing, the cylinder doesn't fit.

The Stupid Fat bloke had left 0.5mm stock to clear which left the diameter 1mm undersize. Told him to take a hike, reran the part, then moved on to the top plate.

I haven't got any experience with rigid tapping and for the sake of one hole, I just limbed it with a tension / compression head.

There. Looks reasonable. 

This leaves the spacers (ties to hold the plates around the cylinder), the M12 threaded push rod and the cylinder o-ring, plus the actual niceties of mounting it on the machine.