Newbie help with a Vicmarc VM90 chuck

[Jean-Francois Theoret]

I just acquired a Vicmarc VM90 chuck. Instruction manual is, for my level of
knowlede, inadequate. I have two questions concerning this chuck:

1. How hard must one tighten the wooden piece on the chuck using the levers?
2. The grub screw: I guess that once the wood has been chucked, I must then
tighten the grub screw? What exactly is the role of this screw? Do I have to
tighten/untighten it all the time?

Thanks

Jean-Francois Theoret

[PMarks1694]

I have recently purchased the VM 90 myself and have been quite pleased with it.
I think the amount you have to tighten the jaws is affected by the material
you are turning. I wouldn't tighten it with anymore than your single hand
reasonbly well hand tightened. Regarding the grub screw, I have found no need
to tighten it, it would lock the chuck on the shaft if you were to reverse the
rotation of the motor.

[Jean-Francois Theoret]

Thank you very much! Very appreciated.

"PMarks1694" <pmark...@aol.com> wrote in message
news:20011224055206...@mb-fh.aol.com...

[Steven D. Russell]

Hello Jean-Francois,

I do not have the VM90, but I have several VM140's in the studio. As the
other poster noted, the pressure you apply to tighten the chuck is dependent
on the material you are working on... Soft timbers will require less torque
than denser species however, be careful about applying too much torque...

On some medium and soft species the pressure can actually cause the timber
to split in the jaw contact area on the boss (dovetail spigot). The chuck
can apply a tremendous amount of torque, more than enough to damage the boss
on some species. I use enough to snug it up and then a bit more. It's a
subjective thing that's not easy to describe.

As for the grub screw... Which one are you referring to? If you mean the
grub screw on the end of the insert, this is used to prevent the chuck from
coming off the spindle if the lathe is switched into reverse. However, if
you do not have a hardened spindle (many lathes do not have this) and an
area to seat the grub screw into (like a Oneway has), then setting this
screw will damage your lathe spindle. :-(

If you are referring to the grub screw on the side of the chuck body, this
is a special screw that is used to lock the jaws on objects that do not
compress, i.e.. brass, copper, acrylics etc. When using these and other hard
materials in the chuck, you snug the jaws on the spigot and then lock the
grub screw down to keep the jaws tight against the spigot. Just remember to
unscrew the grub screw before loosening the jaws.

The grub screw on the insert flange is used to keep the insert tight on the
body of the chuck. This grub screw should be kept tight at all times. The
Vickmark chucks are superbly machined and you will be proud to own one. Take
care and all the best to you and yours! Seasons Greetings!

--
Better Woodturning and Finishing Through Chemistry...

Steven D. Russell
Eurowood Werks Woodturning Studio
Machinery, Tool and Product Testing for the Woodworking and Woodturning
Industry
The Woodlands, Texas

"Jean-Francois Theoret" <jfth...@NOSPAM.videotron.ca> wrote in message
news:MwDV7.24802$YX1.3...@news.easynews.com...

[Jean-Francois Theoret]

I was refering to the grub screw on the side. Than you very much for your
instructions!

Happy Hollidays!

Jean-François

[Joe Fleming]

I have had the VM-90 "let go" of wood because the scroll mechanism
"unscrolled". I have never had this problem with my VM-140, however. I
recommend that you use the grub screw all the time. Just stcik the
appropriate allen wrench on a magnet near your headstock.

Joe Fleming - San Diego
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