The thought of banging on this precision mill is the reason for this little "extractor".
Documented on the Sherline web site and other places on the net is this slick way to
extract your morse taper tools from the spindle.
The spindle is 3/4-16 threaded on the outside for holding tools on the OD of the spindle.
The inside is a MT1 taper socket.
Using this thread the "extractors" are installed prior to installing the Morse Taper tool in the spindle.
Three sizes were made for MT1 tools that insert to different depths. In use the extractor (nut) is backed
down on to the tool after the draw bar is released which pushes the taper shank out of the taper socket.
Not for MT1 drill bits but works great for tools like the drill chuck or fly cutter that provide something to push on.
For drill with MT1 shanks there is another solution that uses a clamp that acts as a pusher on the draw bar.
Simple to make:
First make an arbor from a grade 8 3/4-16 bolt. I turned down the hex head to just under .735" to match the cleanup cut
on the rest of the bolt shank. Easy to put on two 3/4-16 nuts and jam them up. Put the arbor with nuts in the chuck and using
the part-off tool, cut 90% through. Note that I am using the spring loaded part off tool since this is a big stickout
on a little lathe. Spring tool is here:Homemade Parting Tool Spring Type Holder - HomemadeTools.net
Remove nut halfs and finish the cut with a hack saw in the vise. Clean up and test the nut with
an extra 3/4-16 bolt and you have two thin "extractors". Also ended up with a nice 3/4-16 Arbor for the lathe.
I made one more that is about 3/4 the thickness of the standard nut and added one standard nut to the "kit".
Now depending on the MT tool that will be installed just select the right thickness extractor and install it on the
spindle prior to inserting the MT tool and draw bar. When done, release the draw bar and give a bit of a turn to the extractor
and the taper will release. No banging on my mill.
Cheers, JR
Bookmarks