In article ,
Tom the Tinkerer wrote:

[ ... ]

You would be right
at the headstock end of the nose there is an unthreaded portion, which is
where the clamp fits, i will attempt the levering of the collar this
weekend, although finding internal jaws would solve my problem for a while
too..

Note that *some* Emco chucks have reversible jaws. Remove them,
and look at the teeth on the back which engage the scroll plate. If
they look sort of like this:

[ (( (( (( (( (( (( (( ]

They are the normal non-reversible ones. However, if they look more
like this:

[ () () () () () () () ]

(curved both ways on the two sides) they can be installed into the chuck
body backwards. Note that this is more often found on smaller chucks
than what you have, (e.g. one of the styles for the Compact-5, and the
one which came with the Unimat SL-1000) but it just may be that you have
them in your chuck. Note that these are not as strong as the
non-reversible ones, so if you have them, be more careful about cranking
down on the wrench.

Also -- just in case -- are your chuck jaws two-piece? The top
jaws held onto the bottom with Allen head cap screws? If so, you should
be able to unbolt them and reverse them.

I'll have to try and source a new backplate as well. although i feel a
little anxious at cutting the existing backplate off

I understand. It is a last-ditch solution -- and you will lose
the special slit and clampable register collar, so other attempts to
free and preserve the existing one should be tried first.

Best of luck,
DoN.

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