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Mike Turkley
05-22-2007, 7:15 AM
How do you turn the sides of your hollow forms so narrow? Do you leave extra wood to allow turning smaller after the outside of the form is established or make your tennon almost as small as your chuck then turn your outside form?

I try and turn my forms taper before putting into the chuck but after chucking, I may want to clean up the sides towards the bottom some more, so I have to be careful of getting into the chuck jaws.

I only have a SN2 chuck with standard 50mm jaws and a set of spigot jaws.



MikeT

Kaptan J.W. Meek
05-22-2007, 8:56 AM
I figure you can do it either way... I turn outside, then inside, then outside, then inside.. I know it's alot of work, but the wood tells me where it wants to go. I do what ever it takes to get the uniform wall thickness. The "transition area" where the side wall meets the bottom is particularly difficult to thin out. How about a longer tennon?.. or a recess? Try a little longer tennon and you don't have as much to worry about, a hollow form is easy to turn around and turn that tennon or the recess off the bottom. Just go slow and make sure of your tool angles and tool sharpness.. Good Luck!!

Neal Addy
05-22-2007, 10:17 AM
Mike, I generally leave a big ol' fat foot on the piece until I'm almost done. It's the last thing to come off. I turn the exterior to its completed shape first, then hollow. I then sand the interior and most of the exterior (down to the foot), flip it over, reshape (or remove) the foot, and then sand the bottom. It may not be the perfect solution but it works well for me.

George Van
05-22-2007, 1:37 PM
Mike, as the others have said, leave enough extra wood to remove at the end. I rough turn most of my hollow forms. I leave extra at the base to re-turn the tenon and reshape the form after warping takes place while drying. I also allow for beads etc. at the time of roughing so as to have “meat” to turn when dry. If I do not have enough wood to spare, or care not to waste anything and use everything, I use glue blocks as recommended by Wally Dickerman, these work well also. At times I use these for bowls and platters when necessary.

Matt Haus
05-22-2007, 3:22 PM
George,

that's a great idea. I have a few where the foot distorted after the dying process. I LIKE IT!:D

Bernie Weishapl
05-22-2007, 6:56 PM
Mike when I do a HF I do the outside first to whatever I want. Once it is done I move to the inside and finish that. I take my HF's right down to the wall thickness I want. Sand some, put either Watco Danish oil or Minwax Antique oil and let dry.

Mike Turkley
05-23-2007, 8:13 AM
Thanks for all your ideas.


Kaptan: My last hollow form I made a slightly longer tennon. While the tennon did bottom out in the chuck, it held very well. Maybe I'll try an even longer tennon on the next one to give more working room.


George: Good idea! So you're leaving enough material to part off when finished.


Neal: So you're leaving extra wood at the bottom to part off like George is doing?


Bernie: Sounds like you are turning dry wood. All my turnings are from green wood.


MikeT

Neal Addy
05-23-2007, 9:53 PM
Mike, you don't want your tenon to bottom out in the chuck at all. On a 6" (or so) piece I would never use more than a 1/4" tenon. On my Talon this would extend about half-way into the throat of the jaws. The key is to make sure that the tips of the jaws seat against the bottom of the piece. This helps give the piece more support.

In answer to your question, no, I don't leave any extra wood (aside from the tenon) at the bottom. The tenon I describe above is what I was referring to as being removed in the last step.

Hope that makes sense!

Mike Turkley
05-24-2007, 6:57 AM
Makes sense Neal. You're doing what I have been doing all along but run into problems when I want to take another cut on the outside down towards the chuck. I would leave a ridge there where I stopped just short of hitting the chuck.

BTW, I just got a sorby multi-tip hollowing tool and tried it on a small 5.5" diameter maple and it worked great straight from the factory. Man, that thing would cut! In fact so well that I almost cut right through the sides. That one went on the scrap pile. My hollowmaster doesn't cut as well as the multi-tip which means that the hollowmaster tip isn't as sharp as I though it was or with the multi-tip being able to use the rest up close to the form thereby having more leverage during the cut.

Thanks for the info.

MikeT