ME Vol 62 Issue 1513 question

Haven't seen that article but probably would have a slide and groove for location each side and a captive screw for adjustment.

Hello Neil Yes, it has 4 faceplate style slots machined in, radiating from the centre. Into each of these slots a lug with stud is fitted, fastened from the rear of the chuck using a nut & washer. Each jaw is hollow so that it fits over the lug and sits flush with the chuck face. Each jaw has a square caphead adjusting screw screwed in from the outside face/end of each jaw so that once the nuts are tightened up, these caphead screws are used for fine adjustment of each jaw. These appear to be captive, but no way of telling from the photos. This is the part that isn't clear, as the hollow in each jaws is at least half as long again as the lug. Can scan and send copy if required. GeoffH

Yes please Geoff. I went to have a look but my collection doesn't go back as far as Vol 62.

-- Regards,

John Stevenson Nottingham, England.

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Thanks for that Geoff. Yes I see how it works and it's a neat idea. Reading the last part of the text carefully it appears he didn't make the jaws hence the lack of description. Image one jaw in section. You have to outer shape and an inner slot that allows to threaded block to move along. Running thru the jaw is the adjusting screw into the threaded block. The only way to remove a jaw if the threaded block was bolted to the faceplate would be to remove the screw all together.

If you got the end of the threaded screw to sit in a machined hole in the jaw and used a pin to locate the head on the screw by grooving the head you would get a quite rigid setup this way and no fear that when slackened you would loose a screw. A similar setup to how a pinon is fitted into a modern 3 jaw chuck, groove one end, support the other.

-- Regards,

John Stevenson Nottingham, England.