Author Topic: Retracting toolholder to fit QCTP  (Read 26421 times)

Offline DavesWimshurst

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Re: Retracting toolholder to fit QCTP
« Reply #25 on: November 29, 2009, 11:22:54 PM »
My version of a cross slide stop that stops the rotation of the screw:



The stop flips up out of the way:



If I back out more than one turn the stop is pushed up out of the way by the head of the thumb nut on the dial.

It's probably immoral but I do internal threading on the back side of the bore with an upside down tool so the tool retraction action is the same as for external threads.

It just clamps to the outside of the screw housing so is easily removed if it gets in the way, it limits the travel a little when working large diameters.



It is adjusted so that the dial reads 0 when the dial lock screw bumps the stop.  It has worked fine for me for several years now.
Hope this inspires other ideas.
Dave

Offline Darren

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Re: Retracting toolholder to fit QCTP
« Reply #26 on: November 30, 2009, 05:09:59 AM »
Thanks for showing, that is so simple and looks easily implemented  :dremel:
You will find it a distinct help… if you know and look as if you know what you are doing. (IRS training manual)

Offline 75Plus

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Re: Retracting toolholder to fit QCTP
« Reply #27 on: November 30, 2009, 05:51:41 PM »
Can you stand one more way to stop the cross slide?  Hope so as here is the way I do it on my 12 X 36 Asian lathe.

The tapped holes on the saddle for the follower rest are hardly used so I made use of one of them to hold my stop.



This is the stop.  It only works for external threads but that is not a problem for me as external is about all cut.



There is a little flex if pushed hard but I find the repeatability is about as good as the repeatability when using a mic. Once I got the feel of it I stopped looking at the dial each time I started another pass.

In the first picture you can see two holes in the side of the cross slide. These holes are in a position which would allow a stop to be made that could be used for both internal and external threads and would be a more rigid. I may investigate this possibility

Joe