Thread: Balls!

A very interesting approach Tony, nice and simple to. What size bar is used please?
Kryn

I like it.
What size lathe is the ball turner attached to?
Is the reason it is operated from the back related to a travel issue with cross slide?

Not enough room to swing it from the front side of the lathe?

Can we see some pics of the balls you have turned? I am interested to find out if there is much vibration.

Thanks
Grahame

Sacc,

Good work!

I much prefer the over and under ball turner due to their simplicity and rigidity, as the cutting load is directed straight towards the toolpost.

Andrew.

Being mounted at the back means there is nothing forward of the ball so there is a good clear line of sight, but like I said it can also be mounted at front, I just prefer a clear line of sight. I've only turned an acrylic lense and rounded the end of the bar you see in the picture, no indication of any chatter, but I suppose with enough overhang and heavy feed it wouldn't be difficult. I was very exacting with the bore and pivot fit so I don't think you would get any chatter from there. My lathe has an 11' swing so slightly smaller than an AL- 320.
The base is 25mm round bar bored to 17mm for the pivot over 80 mm The cutter head is 15 x 20mm from memory welded in an L shape and then welded to the 25mm end of the pivot. I will be making another of course (as always), but next time I'll probably make the base one piece as well as a one piece pivot/cutter head as soon as I work out how to chuck the base for boring, might have to do a line bore I think. Boring 17mm holes over 80mm is impossible without some chatter.
I was going to make a handwheel for it, but didn't have any suitably sized ally so the lever will have to suffice.
Thick fingers and tablets are not the ideal partners are they?

thats the simplest I have seen yet.....I reckon I could even make one

Never thought I’d be posting pictures of my balls on the web, but here we go:

First picture is the ball hot off the press, second picture is after a bit of a rub with butchers paper. Not saying why my thumb is placed so strategically, but I’m sure you’ll work it out. First time out for this tool and I have to say it is just so easy to set up and so easy to use, far better than my previous vertical type ball turner. if anyone is interested I can post a video, once I’ve learned how to use it properly of course.

I’m surprised no one has ventured a guess as to what the ‘peculiarity’ I spoke of is; so,
when nutting out this design I set three parameters as being the most important:

It had to be easy to set up,
it had to be simple and easy to use, and
most importantly it had to cut perfectly round balls (not something I found easy with my vertical turner).

And there lies the ‘peculiarity, it will only cut round balls, no ovals! You can cut capsule or elongated balls but not an oval, not in the tool as it is.

To cut an oval the tools pivoting point must be below the centre line of the stock/ball. The tool, as I’ve made it is set so that when mounted in the tool post the cutting tool pivot point is central to the work,; so, round balls only.

Not an insurmountable problem though, a height adjustable tool post would solve that problem, failing that, A simple modification to the tool raising it’s mount point. This of course would necessitate the use of packing shims under the tool to raise the pivot point to the central position

You’ll notice the finish on the ball isn’t the best, that’s due to the cutting tool rather than anything else, his morning I just could not get the tool to chatter. When I made the attachment I made it to take 6mm round HSS of which I had two 200mm lengths. What I didn’t know was the HSS was of such poor quality that without coolant and small cuts the bit simply burns and is ground away by the stock.

When I get around to making another (height adjustable next time for cutting ovals) I’ll use square HSS bits, much easier to hold when shaping and much easier to find!

I like it Sacc.

I need to post some photos illustrating what I don't like about mine. SimonL may not be too happy.

BT

Nice work!

I am so tempted to make an under over type too just for a comparison. I have not had a chance to play with mine much. I do have a couple of small projects that I need to use it for.

What shortfalls have you found with yours Bob?

Anyway, back to you and your balls. Nice!!

Simon

Just as a matter of interest, does anybody else have problems making round balls with the standard vetical tool? Invariably I end up with an oval ball, by the time I get it round it's smaller than I intended.

Hi sacc . I like it . And I like how many different design's I've seen
on this forum. I'll have to finish mine.
i was just wondering how you go leaning across the chuck and workpiece to use it.
how often do you think you will use it?
aaron

I could be wrong but wrt ball turning, you get oval balls if you advance the cross slide to the point where the pivot point goes past the lathe spindle axis. Then you end up with a radius along the lathe bed as what you set but the radius across the bed is less.

If you make out the centre point for the tool and dont go past, you should be fine. Never looked into a perminent fix but some kind of perminent marking that lines up the cross slide on the saddle would do but who uses a ball turner that often to warrant a perminent mark? We're not making precision ball bearings so near enough is most likely good enough.

Simon

Simonl
'Near enough is good enough'. Your game, saying that on this forum!

Azzrock
Leaning across the chuck and work piece??? I think you'd have to be a contortionist to do that! With the ball turner located behind the work you actually stand closer to the tailstock than the chuck. The only body part that is near the chuck or work is the right hand operating the lever, but the toolpost is between the arm/hand and chuck anyway. Definitely contortionism!

Rarely/hardly ever/not very often - ummm, probably never. I think I've used my other ball turner once since I made it (and finished playing with it [new toy syndrome]). I'd say this one will be in the 'new toy' bag for another day or so then I'll go on to make another couple of improved versions, after that they'll all go in the cupboard and quietly rust away while I'm busy making other useless items to store in the cupboard so they can quietly rust away too...

This is a strange hobby...

Ha!

Im not in the habit of measuring balls on handles to make sure their eccentricity is exactly 1 )

I couldn’t help myself, it’s just so easy now.

Art imitating butchery; or, butchery imitating art, hmmm, what do you think?