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Thread: Off center turning

  1. #1

    Off center turning

    Has anyone put together a manual for what effects can be obtained by various off center techniques. I have been to a Mark Sfirri demo and the stuff he made was cool, but there just wasnt enough information about how to plan a certain look or shape. Most of the off center Goblet stems etc, look totally unplanned. It seems to me that it should be possible to turn a spiral or a piece with an oval cross section.

  2. #2
    Quote Originally Posted by Perry Hilbert Jr View Post
    Has anyone put together a manual for what effects can be obtained by various off center techniques. I have been to a Mark Sfirri demo and the stuff he made was cool, but there just wasnt enough information about how to plan a certain look or shape. Most of the off center Goblet stems etc, look totally unplanned. It seems to me that it should be possible to turn a spiral or a piece with an oval cross section.
    When it comes to offcenter spindle work, Barbara Dill has it pretty well covered. She has a number of articles and handouts on her website. And her book has even more.

    https://www.barbaradill.com/multi-ax...rs-and-videos/

  3. #3
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    Quote Originally Posted by Perry Hilbert Jr View Post
    Has anyone put together a manual for what effects can be obtained by various off center techniques. I have been to a Mark Sfirri demo and the stuff he made was cool, but there just wasnt enough information about how to plan a certain look or shape. Most of the off center Goblet stems etc, look totally unplanned. It seems to me that it should be possible to turn a spiral or a piece with an oval cross section.
    I've done quite a bit of off-axis, multi-axis and off-center turning on spindles and other things and enjoy it a lot. For example, this little bud vase (with a glass insert for water):

    bud_vase_comp_IMG_8238.jpg

    I've gotten handouts at symposiums, have seen demos by pros and locals and notice there are lots of online resources of specific types off off-axis turning but I've never seen a definitive "manual" covering all the techniques. This is probably because there are so many techniques and variations! Very small changes in parameters can make huge visual differences. I don't know of any one turner who uses all the techniques I've seen myself, and I'm sure I haven't seen them all! To get everything you'd probably need multiple manuals by different people. (And for more fun, they don't all use the same terminology.)

    For example, one common method is to turn a blank between centers and put the points of the drive and live centers at different places on an end or both ends of the blanks. Sometimes the centers are placed on a sequence of points on the circumference of some size of circle drawn on the ends.

    Another way to work is with a jig or special off-center or a techniques to hold work off-center in a standard chuck.

    I learned from Frank Penta one way to work with a standard 4-jaw scroll chuck: mount a spindle blank centered normally between a chuck and a single point, shape the wood some some, then loosen the chuck and move the live center point and tighten chuck to hold it off center and turn some more. This is best done with small diameters and pin jaws on the chuck. You can make amazing crazy shapes this way. Visualizing what to do to get a pleasing end result does get a little easier after doing a bunch but it's still a lot of experimentation for me. (FWIW, I find this method easier and more controllable if instead of holding a tenon or the square end of the blank in the jaws, first turn a kind of a football shape on the blank for the chuck to grip.)

    I don't have many photos of the result of this method but there's one little turning in this "plastics and metals" photo. It's a "crazy golf tee" using Penta's method, turned from an aluminum rod on the wood lathe (with woodturning tools).

    aluminum_brass_plastic_smaller.jpg

    There are so many variables and they all give different shapes even when turning simple "cylinders" without otherwise shaping. The shape possibilities are almost infinite! I find it very difficult to determine ahead of time what the shape will look like. Sometime I start with a couple of parameter and try to envision the result if I remove certain amounts of wood at certain steps. Sometimes I get lucky, sometimes not so much!

    In the photo of the bud vase the blank is turned between centers using points on the circumference of end circles. I used three points on one end and two on the other to end up with the different shapes as viewed from the ends. The biggest goal was to get something interesting to the eye and the hand.

    There are easy ways to make things with spirals of sorts. A gentleman in our Knoxville club, Brian Horais, does this a lot and teaches it. He uses the two end circle technique. Brian is good at visualizing and planning this type of shape. He has a LOT of experience experimenting and creating with this one technique. I'm sure other turners are equally good at planning the shapes using other techniques.

    Check out Brian's work here: https://horais.com/

    I can't imagine how to make an oval cross section smooth all the way around using the techniques I know which leave "hard" arc lines on the surface. (regardless of the method, a standard "simple" lathe gives you perfectly round surfaces or arcs.) When I want smooth I turn the shape then soften the edges with sandpaper. A lot of off-axis pieces I've see have at lease some final shaping with abrasives or carving tools. There are special devices and lathes that will turn oval shapes - In museums I've seen intricate oval turnings such as lidded boxes.

    This shows a simple way to approximate an oval cross section, in this case for a handle. https://www.youtube.com/watch?v=6Gdhaj8R6IA I've made axe handles like this. (BTW, I have the Steb centers shown in two sizes and would hate to turn without them.)

    Sorry, I haven't heard of Mark Sfirri.

    Hey, the first time I saw someone turning off-center was in 1968, I worked in the woodcraft industries at Berea College and at one point a special-order was a casket made from cherry. A guy came in and turned six pieces cherry off-center that were carrying handles for the casket. I found out later the guy was the famous woodturner Rude Osolnick! (1915-2001) Rude (pronounced "Rudy") remains remembered to this day for his iconic candlestick holders: https://americanart.si.edu/artist/rude-osolnik-3647 https://tnlearn.pbslearningmedia.org...%20the%20world.

    JKJ
    Last edited by John K Jordan; 02-01-2023 at 8:17 PM.

  4. #4
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    I have Barbara Dill's book. It's a great reference and offers some methods for acquiring repeatable, definitive outcomes. It's a must have if you plan to do a lot of offset turning, I think. As JKJ points out, there are so many variants though. And no one source covers them all. For the most part, I don't find the outcomes all that attractive. I do like the twisted boxes and tool handles, and some of the bigger spheres-on-offset-cove type sculptures are interesting, if the width is big enough to show well. Narrow spindly things are not my cup of tea.

  5. #5
    Sorby (as in the turning tools) put out a pamphlet a long time back about offset turning and the results.

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