Ball in a Ball

[hockenbery]

A ball in a ball is great fun. People try to figure out how?
In the demo video I show how to turn a ball, hollow it to receive the smaller ball and then pop the smaller ball through the hole. There are also links to handouts I use in demos.

dogwood large ball about 3”


I got the idea for doing a ball in a ball in some conversations with David Springett and after thinking it over for 2-3 years I did one in 2005 two Osage orange balls.

I haven’t found anyone doing this before 2005. However since the principle is the same as the mortis and tenon joint the bodger used in their green oak chairs, it seem likely someone would have done it. The small ball is pinged through a hole slightly smaller than its diameter just like the bulbous tenons of the bodgers were knocked into mortis drilled by a spoon bit which makes the mortise wider than its opening.

Lower left is my first attempt from Osage Orange. Other two are camphor.

A golf ball is a good choice for the small for your first attempt. You know it is round and it has a skin that slides through the hole nicely.

I find lots of logo balls at flea markets.

Most hardwoods work well. I have used pecan, cherry, red gum eucalyptus, bottle brush, Cuban mahogany, maple, and sweet gum as well as the Osage orange, dogwood, and camphor shown above.
I finish all the balls before hollowing and assembling usually 3-4 coats of Waterlox . When I do 3 I put the smallest in the middle sized one then put the middle sized one in the largest. I use a Fibonacci ratio for sizing the balls like 1, 1.5, 2.5 Or 2,3,5. This ratio looks good to me.
A straka chuck works great for holding the balls for hollowing. I also hollow the larger balls held a vacuum Chuck-got to be in you game - get to aggressive and you get a lesson in humility as aggressive hollowing can pull the ball off center in the vacuum Chuck.

Turning a a ball hand out notes

http://swat.hockenbery.net/Turning_a_ball_the_easy_way.pdf


Turning the ball in a cup detail

http://swat.hockenbery.net/turning the ball in the cup.pdf


Ball in a ball Handout Notes

http://aaw.hockenbery.net/A ball in a ball handout.pdf


Simple way to make a Straka Chuck

http://aaw.hockenbery.net/Making a straka Chuck.pdf


Demo video - turning a ball and hollowing the ball to make the ball in a ball
B&B Demo 2010 AAW symposium -

View: https://www.youtube.com/watch?v=fmCvOP2Mpmw

This video has been published with the permission of the American Association of Woodturners (AAW). The AAW and its journal, American Woodturner, are the foremost advocates for woodturning in the world. AAW members include professional woodturners and wood workers, amateurs, gallery owners, artists and collectors, and wood and tool suppliers. To learn more, visit AAW's website at:

https://www.woodturner.org/


This video was first published on the 2010 techniques DVD made by
Phil Pratt and produced by AAW.

 

[RichColvin]

Al,

Thank you for sharing your wisdom. I really appreciate it.

One question: do you have a bunch of Straka Chucks for the sizes you need, or, as with jamb chucks, do you resize them as needed and make a new one when that can’t work?

Kind regards,
Rich

 

[Lawrence Duckworth]

I tried your sphere deal today!
The first one didn't go so great, the skew screwed up the first one by somehow jabbing itself into the ball and then after that the ball spun out in the chuck and burned.
but boy is this a slick process....the second one went great!

 

[hockenbery]

The first one didn't go so great, the skew screwed up the first one by somehow jabbing itself into the ball a

Second ball looks darn near perfect!
I do the turning using a bowl gouge with an Ellsworth grind.

If you can turn a ball with a skew that is a great skill to have.

Michael Hosulak turns balls with a skew. Also a student I had once who was a terrific architectural turner, turned a ball in class using a skew then blew it up when he hollowed it.

 

[Lawrence Duckworth]

I'm not sure where this is going but......

 

[hockenbery]

Al,

Thank you for sharing your wisdom. I really appreciate it.

One question: do you have a bunch of Straka Chucks for the sizes you need, or, as with jamb chucks, do you resize them as needed and make a new one when that can’t work?

Kind regards,
Rich

I missed seeing this. They will hold a wide range is sizes for hollowing.
The opening is cut at 45 degrees which puts the opposite sides at a right angle..
I do have a couple with different size openings since the “donut hole” determines how big an opening you can turn in the ball.

I hold the larger balls in vacuum chucks. I do have a bunch of those. I like the ball to be a 1/3 inside the Chuck. Had. 3” ball in 3” pvc Chuck thought it was great fit with an added piece if foam until I started turning and the ball sucked past the seal...... had to remove and replace the seal to get it out.

 

[Emiliano Achaval]

Second ball looks darn near perfect!
I do the turning using a bowl gouge with an Ellsworth grind.

If you can turn a ball with a skew that is a great skill to have.

Michael Hosulak turns balls with a skew. Also a student I had once who was a terrific architectural turner, turned a ball in class using a skew then blew it up when he hollowed it.

I'll wait until you are in need of a Maui vacation, we can do a hands-on session and a club demo. I have a place for you and the wife to stay, here with me.

 

[Emiliano Achaval]

Second ball looks darn near perfect!
I do the turning using a bowl gouge with an Ellsworth grind.

If you can turn a ball with a skew that is a great skill to have.

Michael Hosulak turns balls with a skew. Also a student I had once who was a terrific architectural turner, turned a ball in class using a skew then blew it up when he hollowed it.

I was watching, again, after many many years, a Richard Raffan video on box making. You do not see anybody nowadays using the skew as much as he did on that video. Probably, you would discourage a lot of turners, LOL, they want to do it with the Easy turning tools.

 

[Lawrence Duckworth]

I think I'll call hockenbery seeds

 

[Dave Hulett]

very cool Al. reminded me of some christmas gifts I made for the family long before I got into woodturning. using a similar techique as you outlined I squeezed a steel pinball into a cube of wood.