Startrite Mercury Chuck Key

[deema]

I would really appreciate any help on identifying what chuck key I need to buy for a Startrite Mercury 5 Speed Pillar drill with a Jacobs Chuck. I bought the drill recently and it didn't come with a key. I had thought I might replace the chuck as its a little rough in one place when you are doing it up. However, I cannot get the chuck off. I'm assuming its a LH thread on the locking collars....but without a proper locking collar spanner its not been possible to get it to move so I'm stuck for the moment with the chuck.

 

[longinthetooth]

Collars are for shaft, chuck's on a taper. Wedge it off. Key Jacobs K32.

 

[deema]

Brilliant, appreciate the help

Many Thanks

 

[longinthetooth]

Chuck might have a proprietary Jacobs taper rather than a more universal Morse etc. I'd leave it on to start with, flood it with WD40 and work its jaws a bit - could it be localised corrosion? or there might be a bit of swarf or something in it?

 

[SurreyHills]

You are meant to be able to get the chuck off by turning it clockwise after loosening the lower collar but I couldn't budge mine (maybe I'm just weak) and I resorted to brute force. You should have 2 collars on the chuck and it's the lower one you should loosen to get the chuck off by either using wedges or tapping the chuck sharply with a hammer. As long in the tooth indicates it's a proprietary taper fitted to the chuck. So if you to replace it then go for a compatible chuck with a 5/8" arbor, according to my measurements.
I want to replace mine with a keyless one but haven't been able to find one cheaply that has a 5/8" arbor (let me know if you find a supply )