Ball Turner...

[Ray C]

My life's philosophy and goal "ultimum utilitatem simpliciorem" (Latin: Ultimate utility through simplification).


Ray

This is one of the less complicated designs I've seen. Great idea!!!

Mike from Canada

 

[NEL957]

I didn't think I was going to make it till tomorrow before giving this thing a test cut. Yep, as predicted, it works. Check-out the fancy temporary handle. BTW, it won't need a fancy worm gear. I took 15 thou DoC and on that 1045 and it cut like butter. That was done in about 4 passes.

I'll make a nice handle tomorrow. Uuuuh, I gotta remember to pick-up a tap on the way home. While cutting the thread for one of the "piston bolts", the one I had was making creaking noises... -You know what that means...

I would like to see the ball in the process. I like the direction, I just see, that is what I mean I can not see how the offset is a plus or not. Show us it at work. Please. Love the Quick Change.
Nelson Collar

 

[Ray C]

OK, maybe this will demystify what was mentioned earlier..

If the tip of the cutter is in front of the pivot point, it makes a concave cut as shown in all the photos.



If you move the tip very far in front of the pivot point, it makes a bigger arc and a bigger groove as shown. Here I've cut a groove that makes a comfortable finger groove.



Here's one where the tip was not protruding very far and a cut was made at the end of the shaft. It makes a concave ball.



To use it, you cut as you normally would but first you set the bit for the desired radius of either concave or convex then you adjust dept gradually with the crossfeed dial (for sideways cuts like the finger groove) or with the carriage position (for cuts on the face end of a shaft like the small concave ball). As the piece rotates in the chuck, you just sweep the tool in it's constrained motion. I still haven't made a handle yet and am just using the crescent wrench for now.

If you want to make a ball, you put the tip behind the pivot point.

Ray

 

[jmh8743]

Hey Ray,

Great idea. I've had a 6" thick 8" dia piece of stock for years......so man ur a genius.

Now speaking of balls = sphere. Right? I need to cut a 24" radius into matching plates, AL. My mill does not tilt. Guess ill have to make tooling, but, howsudoit?

Been contemplating for several weeks.

Mike
Still in Cullman

 

[Ray C]

So, if I understand your task properly, you want to make to big dishes shaped like giant contact lenses...

Hmmm, I need to think about that... Maybe Bill, George, Tony, Tom + others have some ideas... But I will think it over.


Ray

Hey Ray,

Great idea. I've had a 6" thick 8" dia piece of stock for years......so man ur a genius.

Now speaking of balls = sphere. Right? I need to cut a 24" radius into matching plates, AL. My mill does not tilt. Guess ill have to make tooling, but, howsudoit?

Been contemplating for several weeks.

Mike
Still in Cullman

 

[Ray C]

Guys, don't go buggy over making the base out of aluminum. Find a piece of cylinder or something and weld a top on it. Be thrifty and use what's around.

I only used aluminum because I have big chunks of that laying around and it's lightweight. Wouldn't want to lift a solid block of steel that size... It does not need to be round -just approximately the right height but not too tall (the tool holder screw can set height precisely). Weld any old thing together to make a base then mill it flat.


Ray

 

[R2.0]

Ray, do you have witness marks anywhere on the slide to show r=0"? Even more slick would be a scale- it looks like a 6" rule would fit nicely on there. bonus points for a vernier on the slider - the operator could set the ball radius via direct read.

 

[Ray C]

No... Haven't gotten that sophisticated. Quite literally, I suddenly took Monday off work, had nothing planned and decided to make this. I noodled on it for an hour over a cup of coffee and started to make it. Good ideas though. If I ever use this for something, I just might scribe some lines like you suggest.

I had a request for a shaft with a ball end once but, the customer was fine with a cylindrical knob with the edges beveled steeply. I didn't have any immediate plans for this thing...

Ray

Ray, do you have witness marks anywhere on the slide to show r=0"? Even more slick would be a scale- it looks like a 6" rule would fit nicely on there. bonus points for a vernier on the slider - the operator could set the ball radius via direct read.

 

[R2.0]

I know the gunsmiths on the site would find a use for it - custom bolt handles