Return-Path: Received: from slkcpop1.slkc.uswest.net ([206.81.128.1]) by truman.olsusa.com (Post.Office MTA v3.5.1 release 219 ID# 0-52269U2500L250S0V35) with SMTP id com for ; Fri, 25 Jun 1999 09:01:17 -0400 Received: (qmail 24303 invoked by alias); 25 Jun 1999 13:04:11 -0000 Received: (qmail 24296 invoked by uid 0); 25 Jun 1999 13:04:11 -0000 Received: from edsl164.slkc.uswest.net (HELO scottdah.slkc.uswest.net) (209.181.81.164) by slkcpop1.slkc.uswest.net with SMTP; 25 Jun 1999 13:04:11 -0000 Delivered-To: fixup-lancair.list@olsusa.com@fixme From: "Scott Dahlgren" To: "___Lancair list" Subject: bonding and sanding Date: Fri, 25 Jun 1999 07:04:39 -0600 Message-ID: Importance: Normal X-Mailing-List: lancair.list@olsusa.com Mime-Version: 1.0 <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> << Lancair Builders' Mail List >> <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> >> I recently had Greg Kress out to help me with some work on my Lancair. he has a masters degrees in composite repair. Greg felt that the industrial standard rule was to final sand with 80 grit max, 120 grit min and that solvent should never be applied to the bond After sanding as per Boeing and MD standards. Glad he told me this after I cleaned all my bonds with MC prior to bonding..... surface roughness is measured as "R" factor and there is an associated surface area as a function of "R". the area goes up as the cut valleys get deeper which happens as the grit particulates get larger. I work in the synthetic diamond industry and we try to maintain maximum surface area for bonding synthetic diamond to carbide. over the years these interfaces have evolved to a sine wave with an amplitude of ~1mm. looking at a sine wave you can see it has more length to travel/surface area than a flat line. we get 1.5 to 2x the surface area of a flat surface. Hope this helps. Scott >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> LML homepage: http://www.olsusa.com/Users/Mkaye/maillist.html