PDA

View Full Version : Ball in a cube



Jonzjob
1st September 2017, 02:57 AM
<style type="text/css">P { margin-bottom: 0.21cm; }</style> Ball in a cube.


I saw this while looking through some turning web sites and was really interested in the idea. Iv'e got some nice spalted cherry so I though why not? I love a challenge after all?


Well, I got there and I'm really pleased with the result!!


https://farm5.staticflickr.com/4399/36800856731_977bed6c31_z.jpg (https://flic.kr/p/Y4Y1zR)IMG_1476 (https://flic.kr/p/Y4Y1zR) by John (https://www.flickr.com/photos/45489029@N07/), on Flickr


I started with a lump of Merusiers, wild cherry, given to me a few years back by a friend here. Cut it into a perfect, well nearly perfect, cube and started to wonder how the hell I was going to hold it in the lathe. The guy who I got the idea from had a complicated home made ply chuck. Then I remembered the 'button jaws I have, perfect!

https://farm5.staticflickr.com/4427/36935676415_188b602eab_z.jpg (https://flic.kr/p/YgSZMa)IMG_1459 (https://flic.kr/p/YgSZMa) by John (https://www.flickr.com/photos/45489029@N07/), on Flickr


https://farm5.staticflickr.com/4436/36106108104_7599d173a9_z.jpg (https://flic.kr/p/X1zf2f)IMG_1468 (https://flic.kr/p/X1zf2f) by John (https://www.flickr.com/photos/45489029@N07/), on Flickr


So with a lot of trepidation I gingerly started cutting, just down to 3mm depth as that is the diameter of the ball. Then shaping that section of said ball. 5 times of doing that and I was fairly confident, but the 6th and all of a sudden the ball isn't held anymore!! :shock: So lots of checks to make sure all was well and ahead went I. It looked pretty good, but 6 lumps on the ball from the corners.


Somehow I was going to have to turn the ball inside the cube whilst holding the cube, good game, good game as Brucie would say. Holding the ball was no problem, I have done it before making my Lazy Susan.


https://farm5.staticflickr.com/4436/36800754691_77cfb543d6_z.jpg (https://flic.kr/p/Y4Xufx)IMG_1472 (https://flic.kr/p/Y4Xufx) by John (https://www.flickr.com/photos/45489029@N07/), on Flickr


I came up with the idea of a couple of clamps on the bed bars and a cross clamp to hold the cube. It worked perfectly! And I was able to lightly turn the lumps to round with my 1” round nose scraper


https://farm5.staticflickr.com/4396/36940342885_e7d4c39331_z.jpg (https://flic.kr/p/YhhUXx)IMG_1473 (https://flic.kr/p/YhhUXx) by John (https://www.flickr.com/photos/45489029@N07/), on Flickr


That shows when I was sanding the ball and the tool rest was between the clamps for the turning bit. The sanding was really easy with the same setup.


Next was the finishing of the outside of the cube, so back in the button jaws again and very carefulle turn a slight shape to the cube. It made a huge difference. But, the first thing that crossed my brain cell was that the ball was going to be loose in the cube, so a couple of elastic bands did the trick


https://farm5.staticflickr.com/4375/36940356625_d94c938af3_z.jpg (https://flic.kr/p/YhhZ3r)IMG_1470 (https://flic.kr/p/YhhZ3r) by John (https://www.flickr.com/photos/45489029@N07/), on Flickr


https://farm5.staticflickr.com/4407/36132096173_1c258090fa_z.jpg (https://flic.kr/p/X3Srnp)IMG_1471 (https://flic.kr/p/X3Srnp) by John (https://www.flickr.com/photos/45489029@N07/), on Flickr


And the shaping and sanding were quite easy. One of the main difficulties was that the rubber buttons pushed the cube out slightly when they were tightened, so I had to get a soft faced dead weight hammer and BASH, gently, back against the face plate. And, as they say that was the finishing touch apart from sealing it with hard wax oil and polishing with Intercrystaline wax from Rustins. That hard wax oil is wonderful stuff! Anything from bowls to hotel reception wooden floors!

Dalboy
1st September 2017, 04:13 AM
Double post so deleted

Dalboy
1st September 2017, 04:15 AM
Great job on this one John and thank you for the how to.

not sure on relying on the cole jaws to hold a piece like this but then that is just me I will stick to safe turning:roll::roll::roll::rofl::rofl::rofl:

Jonzjob
1st September 2017, 06:16 AM
No problems with the holding Del. I did get a catch once when I took a liberty and it moved forward slightly and was stopped by the tool rest. Clattered a bit but stayed put. It is quite light so even if it did escape it wouldn't do much and I forgot to say that because of the type it is the lathe speed was less than 1000 rpm. I don't have a speed indicator for my variable speed, 3 phase motor, only my engineers mk1 eyeball.

I didn't want high speed because the spaltin weakens the wood structure and I don't like 3 dimentional jigsaw puzzles!

plt43
1st September 2017, 08:27 AM
Excellent piece - and thanks for the step by step photos and guide !

Now added to my "must have a go at this" list.

cheers
phil

Uncle Al
1st September 2017, 08:29 AM
What a brilliant piece of work. Not something I would attempt at the moment, but your photos and description will inspire many to have a go, including myself, but not right now. More practising required!

Thank you for the great photos.

Alan...

Stewie D
1st September 2017, 12:43 PM
Nice work John.

Stewie

turnerted
1st September 2017, 04:40 PM
Great work and an excellent "how to" description .
Ted

Jonzjob
1st September 2017, 04:55 PM
Ta for all of your comments folks. As for doing it, younever know until you try, init!!

I forgot to say that for the final digging out the corners to actually free the ball I used a little 1/4" scew chisel turned upright to use the point vertically. That way I have a 1/8" poinetd scraper??? I have a small set of gouges with a 1/4" parting tool, spindle gouge, round nose scraper, skew, and a 1/8" spindle gouge (that's a bit scary and the tool rest has to be almost touching the spinning bit !! )

dai sensei
1st September 2017, 06:30 PM
Well done WIP and great result. I always wondered how to finish the ball once free and you have answered my question well thank you.

Jonzjob
1st September 2017, 07:13 PM
This is the site I took the idea from

Bottle In A Cube - Woodturning Magazine - woodworkersinstitute.com; (http://www.woodworkersinstitute.com/wood-turning/projects/hollow-forms/artistic/bottle-in-a-cube/)

But as I said the chuck was too complicated for my liking. Especially when I had the button jaws.

powderpost
1st September 2017, 08:56 PM
Excellent W.I.P., thanks. Must have a go at this shortly, when I get back from Japan.

Jim