This is what I’m trying to make:
I hope you haven’t given up on me with this blog. My wife and I spent about a week moving my 92 year old MIL to an old folks home and then a few days recovering from the heavy lifting. We got her new place furnished nicely and my wife sewed some draperies. She seems real pleased with the change after living alone for the last 44 years. Now she has folks of her own generation to socialize with on a daily basis and she has all her everyday needs well attended to.
You might recall that we left off with the ball having been turned on the lathe as shown below.
Mostly finished ball on the lathe above
The next task was to sand off the axle nubs from parting the ball off the lathe. I like to use the disk sander for this because the cups used to hold the ball for the finishing up isn’t so secure when you turn off the nubs.
sanding on disk sander above
After removing most of the nubs on the sander I remounted the ball back on the lathe in some cup holders to finish turning the end grain part of the ball and to sand the whole thing smooth. Note that the center line on the ball which was in a vertical position on the original lathe mount is now horizontal in line with the lathe’s axis.
Ball in the cup holders on lathe above
The finished ball at last! It looks almost round too.
finished ball above
The last job is marking the ball up for drilling. There will be a total of 32 tapered holes in the ball, 20 constellation holes and 12 primary holes. The constellation holes are all drilled first at the same time. Each primary hole is drilled separately afterward and the turning of the 4 inner balls is done before moving on to the next primary hole.
The larger primary holes will be used to turn all 4 balls within the main ball (5 balls total), while the smaller constellation holes are used to help clear waste that can’t be reached by the turning tools.
The marking is done with a compass according to ball geometry to locate all the holes so that they are evenly distributed around the ball. Please note that you need to have an accurate sized ball and it has to be very round (near but not perfect) I’ve darkened the lines to make it easier for you to see.
The primary hole will be located at the center of each ‘flower’ while there will be 5 constellation holes surrounding each primary hole which you can see in the photo below.
The book “Woodturning Wizardry” by David Springett explains how to do the marking.
Marked up ball above
In the next blog I will show you how the 10 constellation holes are drilled while being held with the ball chuck. I hope you find this work interesting. Thanks for reading. The following links cover all the blogs in the series to date.
-- Mike, American in Norway