Return-Path: Sender: (Marvin Kaye) To: lml Date: Fri, 03 Oct 2003 07:39:03 -0400 Message-ID: X-Original-Return-Path: Received: from mta9.srv.hcvlny.cv.net ([167.206.5.42] verified) by logan.com (CommuniGate Pro SMTP 4.1.5) with ESMTP id 2622268 for lml@lancaironline.net; Fri, 03 Oct 2003 00:25:30 -0400 Received: from ValidationPartners.com (ool-18bb9fce.dyn.optonline.net [24.187.159.206]) by mta9.srv.hcvlny.cv.net (iPlanet Messaging Server 5.2 HotFix 1.16 (built May 14 2003)) with ESMTP id <0HM5000B1YQ1CO@mta9.srv.hcvlny.cv.net> for lml@lancaironline.net; Fri, 03 Oct 2003 00:20:26 -0400 (EDT) X-Original-Date: Fri, 03 Oct 2003 00:22:26 -0400 From: Adam Molny Subject: Elevator hinge wear X-Original-To: Lancair Mailing List X-Original-Message-id: <3F7CF982.990841B4@ValidationPartners.com> MIME-version: 1.0 X-Mailer: Mozilla 4.7 [en-gb] (Win98; U) Content-type: text/plain; charset=us-ascii Content-transfer-encoding: 7BIT X-Accept-Language: en References: Something is bothering me about Rob Logan's hinge wear problem. The enlarged hole indicates that the bolt has been rotating in the aluminum hinge bracket. The hinge bracket should not be moving relative to the bolt. The stabilizer side of the hinge has a pressed-in bearing that consists of a sleeve and a barrel-shaped insert (I don't know the proper name for this). Both of these are hard steel, which is supposed to provide a durable bearing surface. When you tighten the nut and bolt, the tabs of the hinge bracket should flex inward to provide clamping pressure against the ears of the barrel-shaped insert. When the elevator moves, the hinge, nut, bolt, and barrel should all rotate together. The only relative motion is between the barrel and the steel sleeve. Was the bolt under-torqued? Are the hinge bracket tabs too stiff to flex inwards? Hinge wear is a particularly troubling issue, since this type of bearing is used all over our planes, especially in the control system. Am I right to worry about this? Adam Molny Legacy #151 > From: Rob Logan > also note the bolt is harder than then Al "hoop". I noticed > black Al oxide from the outside "hoops" after 30hrs of legacy > flight.. One could wiggle the elevator inside the expanding "hoops". > I made a fatter "hoop" and hard coated it.. > > http://rob.com/lancair/2003.05/thumb/new.jpg > http://rob.com/lancair/2003.05/thumb/old.jpg > > -- > Utopian Maturity: Eternity, Liberty, Equality now Fraternity & Altruism. >