Re: [ATM] Bevelling

[Jan Bentz <jbentz@inreach.com>]

Richard wrote:

>Hi List,
>
>I am setting up to bevel/chamfer a 20 inch Pyrex blank. I am
>planning on using a 4 inch diamond grinding wheel which is
>diamond coated on the outer 3/4 inch of its diameter on the flat
>face, with the inner part relieved toward its drive hole. I'll
>be doing this on my vertical milling machine so I can arrange a
>continuous cooling/lubrication jet and I can incline the spindle
>at 45 degrees and use it to drive the diamond wheel. The pyrex
>blank will sit horizontally on a large rotary table which can be
>driven by hand or power.
>
>Now for the question. Does anybody have any guidance on RPM of
>the diamond wheel and the pyrex blank please?. My gut feeling is
>about 1 to 3 RPM for the blank and a few hundred RPM for the
>diamond disk, but I would rather listen to experience than trust
>my gut.
>
>  
>
Richard -- Diamond generator wheels for glass should be run with a 
surface speed of at least 3000 ft/min up to 5 or 6000 ft/min  for 
longest life and most efficient cutting.  This presumes the right bond, 
optimum feed, correct coolent , good balance and a rigid machine.   With 
milling machines with a 4" wheel try 1500 to 2000 rpm for starters and 
see how it feels and sounds. 

Jan Bentz
_______________________________________________
ATM mailing list http://www.atmlist.net/