Centerless sphere grinding?

[borstad]

Can anyone point me to a link (or provide a short description) of how a centerless machine is set up to grind spheres? I've found references to use for billiard/bowling balls etc, but no concrete info. It is my understanding that this is not the same process used for bearings (rill-filing/plate lapping not sure of name, but concentric grooves on counter-rotating plates...) but closer to conventional wheel-regulated centerless grinding.

Trying to visualise how sphericity is acheived on a setup that can grind short plugs with no barreling. My suspicion is that the wheel axes aren't parallel but... ;-)

This is a general interest question btw. I have a project on the go that piqued my interest.

Thanks! This site looks like a great resource.

Matthias

 

[sreid]

Search the web for "Sphere Machines." These are used to make spheres out of rocks. I believe that they are basically counter rotating cones with an abrasive slurry. The rock is initially sawed to a polygon shape.

 

[pardal]

yes it is possible to grind a esphere on acenterless grinder.
here I my city there is a shop that make such machine to do pool balls.
It is made with grinding wheel grooved in sphere radious but with a great angle in the axle , and a little ball instead the blade .
the piece is made by plongee .


Pardal

 

[grinderguy]

I would ask Landis in Hebron Ky. or Royal Master. I tried to use this process a few months ago and found very little help. My parts were better done on a chucking grinder because they had a stud. The ball bearings are done on double disk grinders, Landis Gardner , Waynesboro Pa..
Bob Setree 502-452-9851

Robert Setree

http://www.advanced-grinding.com