Oval diameter on centerless grinding

We are one of the main supplier for automotive 2-4 wheels and industrial rubber part. we are producing for millions of rubber bushing each month. actually we are using centerless grinding machine to fix the outer diameter of rubber bush. in fact we have great number of NG products of oval diameters. the output of our centerless machine producing products with a size of runout of diameter from both sides approx. 0.03 mm. if a side direction measured 25.008, on the other direction measured 25.048 with the direction of X to Y. on the same case, mismatch of dimension on one end side diameter and another end side diameter of the busing also occurred in all of NG products. what happen with my grinding machine?
My team already decreasing the machine speed with reducing the slope of horizontal setting and RPM. but the oval diameters still occurred. if it possible with specify the base rail reducing the oval diameter?
Please give the solutions..
regards

Dino Agung Adha
Engineer - Bogor, Indonesia
May 4, 2009

Hi, Dino. This question seems to be more about machining than about this site's focus, metal finishing, so I can't help. But we'll see if anyone else can. Good luck.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey