Did I buy the wrong chuck?

Depends on the jaws you're using, I suppose. You want a shoulder to seat against (or a mortise, if you're holding inside) to provide you with resistance to movement off axis. Make sure it snugs up tight and cut light.

I use the original NOVA to do goblets, but I have broad faces on the jaws and dovetail up tight. This chuck looks like it's got all the stuff.

I have one of these from Toolpost (but can't find reference to it on their site).

I have it set up with the corrugated grip jaws and don't have a problem. You need to square the end of the spindle off and fit it in the jaws until the squared off end hits the back of the jaws. Tighten up and the spindle has nowhere to go (well until you get a catch).

Good luck.

BillR

Hi Alex I got a link here for you, it has information on how to chuck up your piece of wood,(and more) it is not the chuck you have, but the way you should mound the wood is the same. I would just add that you have to make sure all the mating surfaces on your wood to be fitting and clean, and have the tenon the size where your jaws are round for maximum hold.

Well, no. Grip is simply a matter of pressure. "Hold" is a matter of load distribution. The chuck will certainly hold better if a lesser grip is properly distributed. Not to mention it will not destroy the surface you made for it by application of too great a force per unit area in an attempt to make the total force applied equal..

They hold fine inside or out when their metal is the best match for the wood.

Hi Tony

Yes, You said it better than I did, when I said: "have the tenon the size where your jaws are round for maximum hold" as that is exactly what I meant. Open up the jaws and only the corners are digging in, not much of a hold that way.

It is for just this reason that I have bought my Oneway chucks, (I have three now) their patented jaw shapes, combined with the serrated jaws have an unmatched holding of wood blanks, only the new serrated Nova jaws have equal holding power in the exact fitting range only.

But I think a faceplate would be the better way to hold a blank for this kind of turning, even with end grain, with drilling holes across the end, inserting dowels and screwing the faceplate to the wood with the screws going into the dowels,

One other observation, it seems that the inexperienced, do take on just those projects that need a lot more experience, maybe it is just because of that.

What a suprise, George dissagreed with me yet again. When the chuck is close to closed the jaws are contacting along all of their surface because their radius is based on the jaws being closed. When the jaws are fully open you are only making good contact at 6 places, the outside points of the jaws. Not only am I using logic here but I've tested this several times. Tony Manella

That's not disagreement, except to the disagreeable. I'm going to suppose you read the poster, because you certainly didn't read the post. The differentiation between "grip" and "hold" was made. Grip is generally regarded, to the sorrow of those who practice it, as the result of honking down on the chuck and digging in or out. This is the wrong approach, as I indicated.

Glad to see that you agree that full contact is the way to go.

A mistake I made when I first got my chuck was thinking that a bigger tenon was the best way to grip the wood. So I'd rough a big old piece out and open the jaws up as far as they'd go, then really clamp that sucker down- and I'd still lose pieces in much the way you're describing.

I had an "aha" moment one day when I was loading a cutter into a collet on a mill, and realised that I wasn't getting enough contact between the wood and the inside face of the chuck jaws. Now I make a point of cutting tenons only 1/8"-1/16" larger than the diameter of the chuck when it is fully closed, and it will hold anything I've thrown at it, with minimal clamping pressure.

Not sure if that's the problem you're having, but it's certainly something to look at.

Along that thread, here's a question. When cutting the tenon (slightly larger than the minumum jaw opening) should the length of the tenon favor bottoming out the end of the tenon in the chuck, inside the jaws, or should the turned object bottom out on the top of the jaws? (I"m sure a perfect fit both places would be great, but not so easy to do) Old Chief Lynn

Hi Lynn

Lynn your blank should bottom out on top of your jaws, be it tenon or recess. I got also a link here, you can read all (I would) or go to page 8 and see the write up plus some pictures.

(Big snip of good stuff)

Thanks, Leo, That manual is certainly a lot more than came with my Grizzly. I think I'm beginning to understand. I'll print it out and study a little more before I cut more shavings. Old Chief Lynn

It's the 90 degree resistance to compression provided by the shoulder that you're after. It's wider than the bottom of the tenon, so possesses greater leverage, too. Doesn't take much tenon depth to hold a piece snug to the nose of the jaws, especially if you're using a dovetail, where snugging the chuck wedges the wood down and toward the nose.

I tend to try and make sure that the object bottoms out on the top of the jaws, and not the inside of the chuck. I know that the turned shoulder is true, but there is often a little nub on the end of the tenon left from turning between centers that may or may not be flat, so I stick with the known good reference. Others may do that differently, of course.