I've just had a lot of fun with my new ball-turning attachment on my Myford. I bought the attachment, from RDG Tools (no connection) in response to a client's request for six short, ball-headed stanchions. I soon worked out how best to tackle the job ( an indication that it was a really simple challenge) and then thoroughly enjoyed the exercise. Here's the setup, with an internally threaded work holder in the chuck, and a piece in progress. This is a posed photograph, I hasten to add; I always fully remove the dust sheet , and store work-in-waiting a little further from the action …..
….. and at the end I had produced the goods somewhat faster than anticipated. I'm very pleased with the way the tooling worked, and the finish it gave …..
The only niggle was that the triangular tool tip couldn't reach right into the neck, partly due to the nearby flange, and so a form tool was employed in that corner. I'm now looking forward to the next ball-turning request, anyone for stanchions ?
I have the same tool Ken – and the first time I used it – I discovered that if the 'ball' was too near the chuck face – the tool holder base fouled the chuck (true for both my 3 and 4 jaws). As I normally like to hold work 'short' (to aid with any parting off and general rigidity). I had to start over with a new piece as the first one was too short to extend enough and still hold securely.
Of course, I now know that the work has to stick out a bit. For the amount of ball turning I do, it's not really a great problem for me and the tool otherwise works well within it's limits.
However, for some people's needs, it might be a problem and an "up and over" ball turning design might perhaps be a better cholice.
I've got one too, but had to make a base plate and tap 4 holes to fit my lathe, same prob. with cutting to a face. It is a good tool and I like it, as cheap as making one . I have problems with lining up on both axis. Made a pointed pin and this works for non- critical spheres, is there an easy method to set acuratly ? BTW if rough balls are all you need they can be bought cheaply from "wrought iron" suppliers. Must sort the spell checker one day.