Final(?) reassembly of the tool changer turret and testing with compressed air - and spindle encoder bearings:

Firstly, finish machining the LH threaded MF18 locknut for the turret spindle on the bantam CNC lathe.

Flip it round, shorten it to size and do a bit of chamfering here with the spindle in reverse:

It seems to fit nicely. It's no longer flush like the old castle nut but I can't be arsed to mill 3 slots in it at this stage. If it becomes advantageous to make the nut sit flush, I can always have another go at it later.

Here we go. The turret is back in its rightful place at last.

The bench is a mess but we are almost there now.

Testing with compressed air:

With the solenoid wired up to a 110V site transformer, I can activate the solenoid manually and supply compressed air, to (hopefully) actuate the various components.

Here it is in action. Normally the solenoid would be controlled by the Acorn board which will be watching the status of the 8 way position switch but it's not connected up yet, so I will have to simulate the operation the best I can.

That went well. There's just about enough pressure (4 bar) to drive the turret off its locating pins and start to spin the hydraulic motor. Finally, with the solenoid deactivated, the air is just about sufficient to drive the turret back onto its locking pins. I needed to position the turret at the correct angular position for that to happen, which is why the detent plate and piston is provided. 

Operation is pretty simple, only requiring a single signal (to the solenoid). Once the turret is in the correct angular position, the solenoid can simply be de-energised and the turret will be locked in place.

Obvs it's not operating at anything like the final pressure but from what I can tell, it's giving the impression of functioning as I'd expect.

Perhaps time to look at the 8 position switch now, then think about refitting the turret to the machine. Or would that be premature at this stage?

Spindle encoder:

Although it's not directly related to the turret, the spindle encoder got some attention today, mainly because it had been sitting on the dirty bench, occupying the Evaporust tray. It's now fully dismantled and cleaned up. However, I need new bearings, as the old ones make a fine old noise when spun. The encoder assembly is beautifully overengineered for what it does and was full of grease and muck. These bearings are std 6004Z shielded deep groove jobbies, so I'll replace them with 6004-2RS (double sealed) bearings. When I'm at it, I'll also get some replacements for the belt tensioner jockey pulley. These are 6207Z shielded deep groove bearings, so these will be replaced with 6207-2RD (double sealed) bearings. They are not expensive, so no point paying P&P just to have some shitty skateboard bearings and I don't plan to revisit them any time soon.

I should get these Tuesday-Wednesday (it's Easter bank holiday weekend).