Opinions Wanted – Ball Turner

[edan]

Hello,
I have a project that requires a lot of small radius and a few concave surfaces.
I found this type of turner on the internet and thought I would be the easiest for me to modify for my equipment.
I have designed this to work on a Sherline and I only have .9371 from my cross slide to my spindle center.
My concern is that I have to have part of the turner overhang the cross slide. As I have this now, the cross slide supports the turner to approx the center of the pivot base.
For reference the base is 2.5 x 3.75 x .200. The pivot base is 2.150 in diameter.
The red represents .500 stock.
I only plan on turning stock from .0625 to .375.
I would appreciate any suggestions/opinions from anyone. Especially form anyone who has made this type of ball turner.
Thanks in advance.

(this is a rendering from Alibre and I have left the handle off for clarity)

 

[Deanofid]

I've seen this type of Steve Bedair's design, and it looks like it does a pretty good job from the pictures and videos out there.

If you're worried about it hanging too far off the cross slide, you might want to consider making it to mount in place of the cross slide. I don't know the degree of the dovetails on the Sherline lathe, but if it's a standard 45 or 60, this wouldn't be hard job.

You'd need to buy the dove tail cutter and a left hand tap for making a lead screw nut for the bottom of the ball turner body. The rest of it should only need tools you would normally have for making the turner in the first place. Then the whole unit could be an integral part of the carriage.

Something to think about, maybe.

Dean

 

[Jasonb]

At such small diameters would a form tool not be a whole lot easier.

I have made a version of this ball turner and you need a fair amount of the work sticking out of the chuck, at the small dia's you mention the work would be far to whippy. There are a couple of other styles of ball turner that may be better.

http://www.hemingwaykits.com/acatalog/Spherical_Turning_Tool.html

Jason

 

[tel]

A whole bunch of us made these a while back edan, a bit of a flick through the archives should turn up plenty of info on 'em with adaptation for just about every lathe known to man. RDG Tools in the UK liked 'em so much they offer a commercial version for the Myford. I'm happy with mine.

Here's my version, snd I made a second tool head for concave work.

 

[firebird]

Hi Edan

I have the ball turner from RDG Tools. If you go to this page

http://www.homemodelenginemachinist.com/index.php?topic=3666.0

you will be able to see it in action in a short video + some comments by other members.

Cheers

Rich

 

[edan]

Thank you everyone who took the time to answer my question.
The idea of re-making the cross slide did not even cross my mind. This would help me in “making room” on my Sherline for other parts I have in mind.
The other threads have shown me I missed some excellent ideas.

Thanks again.

 

[Lykle]

Hi all,

I designed and built one that looks like the Hemingway kit ball turner.
An "Over the top ball turner".
I really enjoyed building it and it works too!

One of the things I like about it is that you can adjust the height of the rotating axle. That means that you can turn a perfect sphere, or an elongated shape. Longer than the diameter. Makes for a nice versatile tool.

I included a zip file with the design drawings for anybody who is interested. My QCTP is a vertical cylinder so the block holding the tool just has a vertical hole and a clamp screw. You would need to adapt to your particular QCTP.

Lykle


View attachment ball turner.zip

 

[Blogwitch]

I have survived for many years by making an over the top jobbie utilising the boring head off the mill, it works extremely well indeed.

I am just making one like you are planning, but because I don't have a t-slot topslide and don't want to go drilling into the topslide either, I am making a sub table that locates onto the topslide mounting bolts. Because I have no restrictions on size by doing it that way, it should easily be able to do internal or external curves or balls up to about 5".

Blogs

 

[Richard1]

I have one similar to Lykle built to the designs of J. A. Radford it has done everything I have ever asked of it

 

[d.bick]

Maybe a little big for our applications but heres a spherical Ball turner :