Worry less and grind more. Call back if you lose more than 1/4 of the grinding surface for a Q&A session but don't bother to really worry until you are down to 1/4th of the original tool. Bob May My new web space address is http://webu.wigloo.com/bobmay/ or http://nav.to/bobmay and my new email address is bobmay@nethere.com Bob May