BALLS

[TobyB]

I looked at a couple that had a cup shaped blade a bit like a ring cutter (e.g. http://www.willyvanhoutte.be/en/catalog/show_cat/446) and at other designs which used simple scraper tool like some hollowing systems (e.g. http://www.laymar-crafts.co.uk/tip48.htm) - but the one I have has a bowl gouge-like cutter mounted at about 45 degrees. It seemed to produce a better surface. I made some balls out of (American?) tulipwood and it still generated a lot of tearout but those sanded OK. Some beech balls worked out better, and I made a nicely smooth walnut ball that needed very little sanding. Maybe well set up in the right hands a simple scraper-cutter will work ... Holtzapffel illustrates ivory billiard balls being made that way ... but I'd try to make a ball by hand using gouges rather than a scraper, and all of the instructions on making them talk of such tools as well ... so to me it makes sense for a jig to try to work like that too.

Maybe an expert who know what they are talking about will join this thread?

 

[wizer]

There's the rub Toby. I think, this being not 'proper' turning, it's going to be looked upon with some disdain from accomplished turners. My intention is to produce a volume of balls between 4-12". Those sizes are not set in stone, 10" will probably be ok.

I think the key is making the tool post as 'versatile' as possible. If/when I have one made, I'll try to make it so I can buy 'off the shelf' tooling. To me, that's the hardest part.

 

[Bodrighy]

The right way to turn balls is the way that suits you best. There is no right and wrong way in turning, just a safe and unsafe way. If you need that many and you have difficulty turning them by hand (as do many 'accomplished' turners I suspect) then use a jig.

Pete

 

[TheTiddles]

I'm intending to make a ball turning attachement soon, though it's for up to about 2" diameter which is not really in Whizzers realm and intended to make handle ends etc... not balls in the entirety. The thing that gets me, is how do you hold the ball to do the other end of it given that you have to keep the centre absolutely dead on?

Aidan

 

[wizer]

With these jigs you hold from both ends. I'm not entirely sure how you take off the tenons, but I assume a pair of cup chucks to hold them whilst you finish it off. The only problem is you would need to turn multiple sized cup chucks if the balls were of differing sizes. For my purpose, I don't need them to be perfectly spherical. Near will do.

 

[BMac]

If 'near enough' will do a very cheap method that I use is a cardboard template, a bowl gouge and 80 grit sandpaper. You'd be surprised at how good a job you'd do. As for the tenons, I just slice them off and finish sanding them off on a pad on the lathe.

Brendan

 

[wizer]

Yes I have thought about that. But I do want them to be consistent and I just haven't got the time (or physical ability) to practise, practise, practise. I have it in mind for these balls to be a commercial project and the idea is to be able to batch them out relatively quickly with consistency. Much like some of the pro's use the bowl savers. What I mean buy 'not perfect', is near perfect but not to engineering standards. i.e taking off the tenons will probably alter the concentricity (sp\right word?), but if they look like balls with no obvious flats or lumps, I'll be happy.

 

[BMac]

Got you now, that makes good sense.

Brendan

 

[TobyB]

With the jig, I have a couple of cup chucks ... the drive one just the waste left after I'd parted something off so it already had a tenon to fit the jaws on a chuck. I've found it drives fairly smoothly, but slipping leading to burns was a problem - by lining it with some fairly fine abranet glued in this hasn't been a problem. I made a small cup for the tailstock that fits into the revolving centre.

Once you've got most of the ball, I used these cups having rotated it to take the tenons off, to get a good round thing. I've then loosened it for sanding so it's only lightly held, making it easy to turn without stopping the lathe so you can sand x, y and z axes evenly.

 

[duncanh]

One change you could make to the design - instead of the horizontal bar resting on a small rectangular plate like in the photo it could rest on a larger base that should support it along it's length and during it's whole arc.
This plate could be metal or perhaps thick mdf and could perhaps have a leg supporting it that goes down to the floor.

 

[wizer]

Thanks Duncan. I'd considered that and I think it's a sensible option. The Laymar Crafts version is done like that. Makes a lot of sense, especially the leg.