chucking: innie vs. outie

I have a Barracuda 2 chuck. What are the advantages and disadvantages of chucking on the inside vs. the outside of this chuck?

Are these true of all chucks?

Thanks!

Mark I use a tenon with my chucks. I will on occasion use the chuck to expand in a recess. I like the tenon better. I was told by a couple of pro turners that the tenon is safest. I haven't lost one with a tenon but did have one come off when using a recess. As far as all chucks I can't tell you except some use a dovetail and some use straight sides.

Mark Kosmowski said:

I have a Barracuda 2 chuck. What are the advantages and disadvantages of chucking on the inside vs. the outside of this chuck?

Are these true of all chucks?

Thanks!

Click to expand...

If your chuck has dovetail jaws, by chucking inside (using a dovetail shaped chisel) the wood can't come loose. I only chuck a bowl on the outside for smaller items where I can't make a hole large enough to get inside or to finish the bottom of the bowl.

I've done both, but I prefer to chuck a tenon from the outside instead of expanding the chuck into a recess. I've cracked pieces with an expansion chuck, but then again I've crushed a tenon from the outside to the point where it broke the first time I took a heavy cut. (CA glue was my friend on that bowl. See the attached pic. It was taken after the bowl was done, right before I parted off the tenon. It was a 17" or so natural edge oval bowl.)

Paul's point about dovetail jaws is correct, but some chucks use a dovetailed tenon, so it's not always just for recesses. You can still blow one out of dovetail jaws, regardless of whether they are on a tenon or in a recess. Don't ask me how I know that.

The innie vs. outie debate is valid for pretty much all chucks, but it does vary with different jaw set on those chucks. One of the jaw sets I have for my Supernova 2 is the Power Grip. These seem to be better suited for tenons than recesses. The serrated jaws on your Barracuda 2 will likely do best on tenons, too. Other jaws may do better in recesses than tenons.

Using a recess for chucking allows you to use slightly more of the blank than when you turn a tenon to grip. Most chucks will require a recess of only 1/8" to 1/4" deep to have a secure grip.

The disadvantage as others have said is that if you over tighten/over expand the chuck jaws in the recess you can split off the wood forming it. I have found that it is not necessary to really over tighten if the recess is formed to match the jaw profile of the chuck being used.

With a tenon a similar problem can happen when the tenon snaps off under pressure. The chuck manufacturers have foreseen this problem by creating jaws of different sizes which have larger capacities for larger blanks. For instance the standard 50mm jaws are recommended by my manufacturer for bowls up to 10 inches whereas the 100mm jaws are recommended for 12-14 inch bowls. Larger deeper diameter jaws with serrations in addition to the main gripping profile (dovetail for most jaws) are your best bet for maximum holding power.

I use spigot jaws which are slightly longer in profile and are serrated on the inside in addition to having a dovetail. This profile allows me to very securely grip stock by a tenon and hollow deeply without fear of the stock coming loose.

It all boils down to what you want to accomplish.

I always use a recess when doing platters, on boxes I always use a turned tenon on a glue block.

On bowls, I drill a recess where the inside of the bowl will be and mount it that way. Bring up the tail stock and turn a tenon either from the extra wood or on a glue block.

Al long as there is enough wood around a recess, you will not crack the wood.

Mark Kosmowski said:

I have a Barracuda 2 chuck. What are the advantages and disadvantages of chucking on the inside vs. the outside of this chuck?

Are these true of all chucks?

Thanks!

Click to expand...

I use the tenon on occasion, but I prefer to chuck bowls and platters inside.. I like the inset bottoms and often I'll cut away the dovetail on the final finish.
That said, I haven't done any really large bowls, but I think it more likely that I should use the outside tenon when I do.