Having searched high and low for the chuck key, it seems to have walked. Not a huge issue as it gives me the chance to make a NEW and IMPROVED version. One issue with the 5C chucks is how many times you need to turn the key to close and release collets never mind swap them. As cordless drills are dirt cheap these days and include torque clutches it seemed an ideal choice, I doubt this will be the only key I make. A quick look in the scrap tray produced a bit of 13mm silver steel. I made some quick measurements of how long each end needed to be then cut some clearance grooves with the parting tool. Did I mention the key is being made in the shaper..... Ooooooh shaper porn.....
I used the ER32 blocks I have to make the 3 and 4 sided keys. With the collet block locked tight you can use the nut as your reference, each time it's turned. OK an afternoons work in the shaper would be but a few minutes on the mill, but sometimes its just nice to do things this way.
Swap blocks to do the 4 sided key and just watch the shaper do it's thing. I worked out the dimensions I need and how much to remove from each side about 0.079" and jotted that on the clapper box of the shaper so I wouldn't forget.
The final result, my Chuck Chuck Key, since each end is in a chuck. Just break the edges with a file and test for fit, no problem. Final picture shows the key in the drill, it works a treat and makes good use of the clutch on the drill.