How do you chuck up rough turned bowls?

I start my green bowl blanks between centers, rough turn the outside shape and turn a tenon, not a mortice, for the chuck. This allows me to change the orientation of the blank to balance the grain features or the position of the heartwood vs. sapwood before forming the tenon. I use a tenon rather than a mortice because it places the wood in compression in the chuck instead of tension. Compression is stronger and the tenon can later be incorporated into the foot of the bowl. After the rough turned stock has stabilized, I use a "bung" in the headstock end to friction drive the blank squeezed between the bung and the live center in the tailstock and re-turn the tenon round. Then use the rounded tenon to grip the piece and turn to completion, except for reverse turning the bottom to clean it up and form the foot or whatever is going to be the bottom. The "bung" is a scrap of wood that can be held in the chuck, on a faceplate or with a taper to fit the drive spindle and has a slightly rounded end to roughly fit the inside surface of the rough bowl. A piece of leather or mouse pad between the bung and bowl helps to cushion the work. The live center fits into the hole left when the tenon was originally formed since it will still be in the approximate center of the stabilized piece. Rotate the rough piece by hand before re-turning the tenon to see if is pretty well balanced and if not, make small adjustments until a compromise is met. Then go to town! Joe Keeler-Cincinnati

I rough on a pin chuck, or with my pin jaws by boring a 1" hole in the blank and grabbing. I turn outside, making my recess for reversing at the last.

Reversing to clear the inside, I just leave a pillar of about 1 1/2 ". Means I can just rebore the center when dry and work as before. Last to go is the pillar. Keeps everything between centers until the very last, and me out of the throw zone for the entire process. I think they make pin jaws for Oneways, don't they? If not, a pin chuck is an easy thing to fabricate.

Smaller stuff starts on a screw center, where a 3/4 pillar remains.

Like Joe, I rough turn all of my bowls between centers, which allows one to make adjustments as necessary to take advantage of the grain of the wood. I also turn a tenon on the bottom for the chuck to grasp. I use large jaws (4" or more) for the chucking. After the blank has dried, I mount the chuck to the lathe and use it as a drive center to again turn the bowl between centers. The center was still in the foot from the rough turning. The bowl seems to easily center onto the chuck jaws. I then turn the tenon round and make it ready to be gripped by the chuck. I also turn the outside of the bowl round while it is mounted in this manner. I then reverse the bowl and grip the tenon in the chuck jaws and final turn inside and out. I reverse chuck onto a jam fit chuck, a Longworth Chuck, or a vacuum chuck to finish the foot.

Incidentally, the use of a mortise in the foot of the bowl can be very bad with some woods. I've seen several bowls that split in half while the turner was final turning. There can be a tremendous force applied by the expanding chuck jaws and the wood is only so strong.

Hope this helps a bit.

Fred Holder

Derek, Put the inside bottom of the rough turned bowl against the stronghold chuck jaws........bring the tailstock up and tighten snugly against the "misshapen mortise"..............clean up the "misshapen mortise"..............mount the bowl in the already mounted chuck and jaws...........finish turn and then sand as normal. If you find you are too heavy-handed and the bowl slips while doing the clean-up then put a fold of paper towel between the jaws and the inside of the bowl. HTH

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M.J. Orr

I always use the tenon method for my Stronghold and just put the dried bowl back in the chuck. I can only recall one tenon that I considered unsuitable for holding the bowl after drying. Most of my bowls are under 16". Billh