Woodworking Online

[Keith Young]

Hi
I a newbie to chucks. Bought a Nova compact chuck.
Question
Bowl keeps comming off chuck even when applied with full strength.I am
mounting using the outside diameter of the ridge i formed.
I will try the other method of mounting inside and appling outward pressure.
I notice that the jaws are smooth when i expected them to be serrated!

Any help would be appreciated

Thanks
Keith

[Arch]

Keith, be sure to make your tenons or dovetails short enough so the jaw
faces register against the workpiece. Make tenons/dovetails of a
circumference that the jaws form a circle. _Don't over tighten
excessively---you are holding and driving---not wringing or cutting
notches.
_Do recheck tightness shortly after beginning or after a long rest.
Arch

Fortiter,


http://community.webtv.net/almcc/MacsMusings

[George]

Don't think grip, think wedge. I don't own a Compac, but the jaws on my
Nova have a dovetail in and dovetail out feature. If you're holding a
tenon, your objective is to get the inside wedge to draw the piece tight
against the face of the jaws. Prepare the piece with a tenon about a
quarter of an inch greater than the minimum inside diameter of the jaws, and
a 1/4" or so greater diameter surface for the face of the jaws to bear
against. This may be _mildly_ undercut to ensure proper mating, but in any
case should have no torn pieces of grain or dust to interfere with flat to
flat mating surfaces. I take the nose of a skew and sever the fibers
mildly at the junction of the small and large, to make it easier for the
wedge to push them below, rather than just compress them. The tenon should
not bottom on the base of the jaws. Trying to get it to do so will often
deny you the better grip and greater leverage gained by the nose bearing
against the flat surface on the piece. other than that, a quarter inch or
longer should hold almost anything, with green wanting a bit more.

For inside holds, take a peek at
http://personalpages.tds.net/~upgeorge/index.html Once again, don't think
grip, think wedge, and snug is enough. One point I want to emphasize is the
use of water-thin CA to firm up wet wood on an inside grip. Apply to
refusal in the recess, turn by hand to disperse, and be sure to level it
after it's cured, so you have a smooth surface to wedge. You may also do
some decoration, if that's your thing, to the inside the recess before
reversing, as long as you preserve the flat mating surface for the jaws.

You don't want serrations, because they don't do them right. They're
symmetrical, meaning as they bite into the wood they as likely to push away
from a snug shoulder as not. If they were wedge-shaped, might make a
difference. Crushed or torn fibers from serrated grips can interfere with
reseating the jaws if you should get a monster catch, too. Better to go
with the surface which spreads the load - smooth.

"Keith Young" <kyoung@nl.rogers.com> wrote in message
news:ckrcmn$b43$1@nntp-stjh-01-01.rogers.nf.net...

[Bruce Ferguson]

Check and see if the jaws have a dovetail shape. Make the same dovetail
shape on the tennon you are gripping with the chuck jaws. I usually use a
skew chisle on it's side like a scraper. Useing the skew on it's side as a
scraper very carefully bring the long point into the corner of the tenon and
bowl. This will make a dovetail on the tenon with the idea to mach the
dovetail on the chuck jaws. I hope this helps.
"Keith Young" <kyoung@nl.rogers.com> wrote in message
news:ckrcmn$b43$1@nntp-stjh-01-01.rogers.nf.net...

[Barry N. Turner]

I have a Compac chuck. I find that it holds better in the expansion mode.
Cut your recess about 1/4" deep with a dovetail shape that matches the angle
and diameter of the jaws.

Barry


"Keith Young" <kyoung@nl.rogers.com> wrote in message
news:ckrcmn$b43$1@nntp-stjh-01-01.rogers.nf.net...

[Keith Young]

Thanks everybody for the advice. Just got back from the country. Will try
your suggestions!

sincerely
Keith
"Barry N. Turner" <barry712@bellsouth.net> wrote in message
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