WHAT IS A CHINESE BALL?
Here’s a photo of the kind I am attempting to make. There are four balls encased in the outer ball which is about 2-7/16” in diameter. Please note that it is turned from a solid piece of wood on the lathe.
I first became aware of Chinese balls while visiting Hong Kong as a young sailor in 1957. I saw some in a shop made from solid ivory. I could see they were made from solid pieces with no gluing. I should have bought one, but they were too expensive for me. During the years after being discharged from the Navy, I wondered off and on how those balls had been produced, but not enough to try and find out.
BACKGROUND FOR THIS PROJECT
I bought a book by David Springett entitled ‘Woodturning Wizardry’ at my local woodworking store. I had heard that the book had some interesting projects and chucks, so I bought it without leafing through it. When I did finally get time to read it I was amazed that one of the projects was how to make Chinese balls similar to the ones I had seen in Hong Kong, Though these wooden ones were not intricately carved after turning as the ivory ones. Here is a link to Springett’s fine book on making them.
PURPOSE OF THIS BLOG
I’m not intending this as a tutorial blog. The book is far better on the subject than any how-to that I might attempt. I just thought that some of you might be interested in seeing something a little off the beaten path. I also thought that it might inspire others to give it a try.
This will be a challenging project for me and perhaps some others, but a snap for folks who already possess some of the skills required. Referring here mainly to metal working skills and woodturning.
I plan to share with you my failures and successes with this project for better or for worse. This will reveal some of the pitfalls that I have encountered so that others might avoid them. The idea is: If I can do it so can you.
1. Make special turning tools
2. Make a ball cutting jig for the lathe
3. Make a wooden chuck to hold the ball workpiece in various fixed positions for drill/turning,
4. Make a special tool rest for the lathe or an adapted standard tool rest.
5. Standard tools needed: Metal cutting hacksaw metal files (small and regular), twist drill bits in various sizes, a Jacobs bit for the lathe tailstock, a drill press (small or large), A tap & die set.
6. Suitable wood to turn the balls from (described in the book)
7. A small butane/propane torch. (cheap at most hardware stores).
8. A center punch for steel that can be used for marking out holes to be drilled in the cutters and tool holders.
9. A vise to hold the steel in for sawing out the steel cutters and filing the cutter profiles.
SOME OF THE WORK CARRIED OUT TO DATE
I bought some steel plate cut-offs from a local engineering firm at a good price. This was unhardened plate of a decent quality. I got 1/8” and 1/4” plate. The cutting tools are made from the 1/8” plate and the tool holders from the 1/4” plate.
The thick plate for the tool holders was hard to cut by hand and the jigsaw was no better, so I chain drilled around the layout marking and then cut the thin part between the holes with a metal cutting blade in my jigsaw. The drilling took some time, but it was much easier physically to do. The cutting to separate them from the plate was done in minutes. I first painted the plate with typing correction paint and them traced them using a cardboard template. Here are some pics of it.
After cutting them out I ground the rough edges smooth with my bench grinder, tapped two holes in each to hold the slotted cutting tools and then I polished them. No hardening was required for the tool holders.
I also made cardboard (cereal box) patterns for the five cutting tools made from the 1/8” plate. I used a hacksaw to cut them out and file/ground the rough edges. I chain drilled holes for places I couldn’t get to with my hacksaw. I sawed the slots in these with a metal blade in my scroll saw, but handheld coping saw with a metal cutting blade would also work well here. The tip of these cutters have to be hardened and tempered. Heat to cherry red and then douse in a bucket of cold water to harden, then reheat to a light blue color and douse again to temper.
I turned these from some white oak stock I had on hand. I turned the first one the way I like it, then I made a simple pattern from the inside curve (or cove) and used that to help duplicate the others. Here is a photo of the finished turning tools.
That’s it for today. I will show you the ball cutting jig in the next episode. I will try to keep the next blogs less wordy now that I have explained what the project is all about. Thank you for reading. The following links cover all the blogs in the series to date.
-- Mike, an American living in Norway.