Return-Path: Sender: (Marvin Kaye) To: lml Date: Thu, 06 Mar 2003 14:17:17 -0500 Message-ID: X-Original-Return-Path: Received: from mailnw.centurytel.net ([209.206.160.237] verified) by logan.com (CommuniGate Pro SMTP 4.0.6) with ESMTP id 2045393 for lml@lancaironline.net; Thu, 06 Mar 2003 13:20:32 -0500 Received: from downstairs (pppoe2048.gh.centurytel.net [64.91.54.56]) by mailnw.centurytel.net (8.12.8/8.12.8) with SMTP id h26IKV2K027977 for ; Thu, 6 Mar 2003 10:20:31 -0800 (PST) From: "Robert Smiley" X-Original-To: "'Lancair Mailing List'" Subject: RE: [LML] Re: LNC2 cowl stiffening X-Original-Date: Thu, 6 Mar 2003 10:20:33 -0800 X-Original-Message-ID: <000c01c2e40d$13c328a0$927dfea9@downstairs> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook CWS, Build 9.0.6604 (9.0.2911.0) X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2600.0000 Importance: Normal In-Reply-To: George, You probably already know this but I will say it anyway for benefit of others. The ramps you added above and behind the top cowl openings quickly and abruptly ended without proper tapering about 6 inches behind the opening. This created a very stiff section which abruptly ended at that edge hence any bending forces were all concentrated at that edge. The thin glass cowling could not resist that load and cracked. What was created was a 6 inch moment arm with a stiff rigid lever. The solution is to taper the reinforcement (like the fishing rod concept) to allow rigidity but increasing flexibility to absorb vibration and stresses in a smooth transitional manner without concentrating forces at a single point. Eventually near the edge perhaps midway or halfway back from the front the tapering can be down to one bid of glass. Think rigidity with increasing flexibility and perhaps we may be able to solve the problem of stress cracks. Bob Smiley