removing Clarkson chuck from mill

Michael Gray

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Mar 6, 2009, 9:15:41 PM3/6/09

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OK, we have the Tom Senior mill at school with the vertical S type head
and a Clarkson chuck fitted.
How the heck do we remove the Clarkson chuck? Tried today by loosening
the drawbar bolt and tapping to release any taper that may be in the
spindle (MT3 or R8?). Tried several times without any movement at all.

HELP, what do we try next - a bigger hammer? oxy-acetylene cutting
torch :-).
Anyone done this and knows THE WAY? All reasonable suggestions will be
read and heeded.

TIA, Mike in BC

Charles P

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Mar 7, 2009, 2:59:37 AM3/7/09

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On Sat, 07 Mar 2009 02:15:41 GMT, Michael Gray <mi...@inthesticks.net>
wrote:

Bigger copper hammer.
Don't be tempted by oxy

Charles

peterc...@hotmail.com

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Mar 7, 2009, 8:24:53 AM3/7/09

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The reason for the sticking is often that the chuck was fitted when
the spindle was warm and the chuck cold, the spindle has now shrunk
onto the chuck. the way to deal with this is to get them both warm
with, say, a hot air gun and then cool the chuck with ice or a more
scientific method like dry ice or notrogen, and the get the hammer
out.

Peter

Emimec

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Mar 7, 2009, 5:25:57 PM3/7/09

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"Michael Gray" <mi...@inthesticks.net> wrote in message
news:hNksl.15647$Db2.2346@edtnps83...

Michael
I think you will find that the damping ring on the Clarkson has a left
handed thread. The way to remove the chuck is to put a thin flat open ended
spanner on the two flats that are on the end of the spindle, the bit between
the Clarkson and the machine. This stops rotation while you use another
larger open ended spanner to wind the damping ring up towards the spindle,
where your other spanner is. A good tug, and it should "break" the taper
away, assuming you remembered to undo the drawbolt.
Bob

Emimec

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Mar 8, 2009, 4:02:32 AM3/8/09

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"Michael Gray" <mi...@inthesticks.net> wrote in message
news:hNksl.15647$Db2.2346@edtnps83...

Michael
Further to my last post, I forgot to mention that if your Clarkson is the
newer version there most likely wont be spanner flats on the damping ring,
but holes for a Tommy bar.
Bob

Michael Gray

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Mar 8, 2009, 12:10:02 PM3/8/09

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That's the one, holes for a C-spanner.
Thanks for all the advice folks. will try again this coming week.
Mike in BC

Michael Gray

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Mar 11, 2009, 8:07:00 PM3/11/09

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Yipee! Was in subbing today and found a solid copper 1/2" bar, made a
wrench out of 2"x1/8" steel to fit the flat on the spindle, put a pipe on
the C-spanner. Loosened drawbar, yarded on pipe, wound dampening ring up
as far as she'd go, half a dozen good whacks on the copper bar resting on
the drawbar nut and .... BOB'S YOUR UNCLE!!
The grease in there was like varnish and took Gunk to loosen that up, so
now we have a 2MT spindle ready to accept endmill holders for Weldon
shank endmills at much lower cost than the Clarkson type previously
needed.
Also have one very decorative Clarkson collet chuck ready for the few
remaining screw-end endmills left in the box.

Thanks to all who suggested.

Mike in BC

john

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Mar 6, 2023, 3:01:57 PM3/6/23

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Clarkson chuck

Hi Mike 13 years after your post I have just acquired a Tom Senior mill and I am searching for some Clarkson collets. By any chance do you still have the chuck and or the collets?
I live in Vancouver BC Thanks John

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