X-Virus-Scanned: clean according to Sophos on Logan.com X-PolluStop-Diagnostic: (direct reply)\eX-PolluStop-Score: 0.00\eX-PolluStop: Scanned with Niversoft PolluStop 2.1 RC1, http://www.niversoft.com/pollustop Return-Path: Received: from smtpauth08.mail.atl.earthlink.net ([209.86.89.68] verified) by logan.com (CommuniGate Pro SMTP 4.3c4) with ESMTP id 869301 for flyrotary@lancaironline.net; Thu, 14 Apr 2005 17:56:14 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.86.89.68; envelope-from=jerryhey@earthlink.net Received: from [65.176.160.182] (helo=earthlink.net) by smtpauth08.mail.atl.earthlink.net with asmtp (Exim 4.34) id 1DMCJ4-0005ZI-1s for flyrotary@lancaironline.net; Thu, 14 Apr 2005 17:55:27 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=simple; s=test1; d=earthlink.net; h=Date:Subject:Content-Type:Mime-Version:From:To:In-Reply-To:Message-Id:X-Mailer; b=iz0cA+cUhRsi6KtHiG3xe9iQC8mjR6YQQizUpYlX0q0BoequGtvOukGBDLzNfAsn; Date: Thu, 14 Apr 2005 16:56:58 -0500 Subject: Re: [FlyRotary] V shape Apex Seal Slots? Content-Type: multipart/alternative; boundary=Apple-Mail-2--82851306 Mime-Version: 1.0 (Apple Message framework v552) From: Jerry Hey To: "Rotary motors in aircraft" In-Reply-To: Message-Id: <1F9C8DD5-AD30-11D9-A4D0-0003931B0C7A@earthlink.net> X-Mailer: Apple Mail (2.552) X-ELNK-Trace: 8104856d7830ec6b1aa676d7e74259b7b3291a7d08dfec790e79f350490ac4f2d67e5604784b970f350badd9bab72f9c350badd9bab72f9c350badd9bab72f9c X-Originating-IP: 65.176.160.182 --Apple-Mail-2--82851306 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=ISO-8859-1; format=flowed Ed, I just measured my used (slots not yet thoroughly cleaned) =20 rotors and the slots are 1.86 and are uniform from top to bottom. =46rom=20= now on this will be a critical measurement when assessing engine=20 condition. Jerry On Thursday, April 14, 2005, at 02:51 PM, Ed Anderson wrote: > Well, I continue to gather more information on the seal failure.=A0 I=20= > measured the apex seal slot width at it bottom (where you would expect=20= > little wear) and at its top.=A0 These are the results on the "good"=20 > rotor, I didn't bother with the "bad" rotor. > =A0 > Apex Location=A0=A0=A0 =A0=A0=A0 =A0=A0=A0 Base=A0=A0=A0 =A0=A0=A0 =A0=A0= =A0 Top > =A0 > Seal1=A0=A0=A0 =A0=A0=A0 =A0=A0=A0 =A0=A0=A0=A0=A0 =A0=A0=A0 =A0 = 1.99mm=A0=A0=A0 =A0=A0=A0 2.16 - 2.26mm > Seal2=A0=A0=A0 =A0=A0=A0 =A0=A0=A0 =A0=A0=A0 =A0=A0=A0 =A0=A0=A0 = 1.98mm=A0=A0=A0 =A0=A0=A0 2.22 - 2.25mm > Seal3=A0=A0=A0 =A0=A0=A0 =A0=A0=A0 =A0=A0=A0 =A0=A0=A0 =A0=A0=A0 = 1.98mm=A0=A0=A0 =A0=A0=A0 2.18 - 2.20mm > =A0 > Clearly the slot is larger at the top - is this due to design or is=20 > this due to wear?=A0 Lynn??? Anybody? > =A0 > In any case I found the specs for the space left between seal and slot=20= > side after you stick an Apex seal in the slot, again in the good rotor=20= > (I used a new seal), the max limit permitted (specs) is 0.15mm,=A0 ALL=20= > the slots would accept a 0.15mm leaf gauge blade between the seal and=20= > top of the apex slot and some would accept a 0.18mm blade.=A0 Clearly = at=20 > or outside the max limits. > =A0 > As I rotated the rotors around their housings before I completely=20 > disassembled the engine, I noticed that the apex seals seemed to be=20 > leaning quite a bit as they brushed=A0along the housing walls.=A0 I = think=20 > these measurements indicate I either got a rotor set =A0that was on = its=20 > last legs or something cause abnormal wear.=A0 Since the rotors were=20= > used, I have no ideal how many miles or how hard the miles may have=20 > been.=A0 I have read that apex slots can become worn sufficiently that=20= > the apex seal will fold over the edge - and a piece of one apex seal=20= > certainly did. > =A0 > The question is did it fold over due to a foreign object first=20 > breaking the seal or did the seal break because its center section was=20= > encountering increased drag and bending motion compared to its ends?=A0=20= > The ends stayed in place. > =A0 > =A0 Upon closer examination it appears there are faint =A0"chatter" = marks=20 > on the inside of the rotor housings, you can see them visually and=20 > when I move my fingers over them I can detect a very faint variation=20= > like a wave pattern.=A0=A0 The rotors were used also=A0and =A0I = certainly=20 > don't recall after 4 years - but they could have been present then.=A0=20= > Fortunately, I do have a set of practically brand new rotor housings -=20= > although they are not turbo housings - well, the plus side may be=20 > easier to muffler {:>) > =A0 > At this point I am inclined toward new rotors to h___l with the=20 > expense.=A0 I'm going to get hemorrhoids if this keeps up {:>).=A0 > =A0 > Just though you would like to know. > =A0 > Ed > =A0 > Ed Anderson > Rv-6A N494BW Rotary Powered > Matthews, NC > eanderson@carolina.rr.com --Apple-Mail-2--82851306 Content-Transfer-Encoding: quoted-printable Content-Type: text/enriched; charset=ISO-8859-1 Ed, I just measured my used (slots not yet thoroughly cleaned)=20 rotors and the slots are 1.86 and are uniform from top to bottom.=20 =46rom now on this will be a critical measurement when assessing engine condition. Jerry =20 On Thursday, April 14, 2005, at 02:51 PM, Ed Anderson wrote: ArialWell, I continue to gather more information on the seal failure.=A0 I measured the apex seal slot width at it bottom (where you would expect little wear) and at its top.=A0 These are the results on the "good" rotor, I didn't bother with the "bad" rotor. =A0 ArialApex Location=A0=A0=A0 =A0=A0=A0 = =A0=A0=A0 Base=A0=A0=A0 =A0=A0=A0 =A0=A0=A0 Top =A0 ArialSeal1=A0=A0=A0 =A0=A0=A0 =A0=A0=A0= =A0=A0=A0=A0=A0 =A0=A0=A0 =A0 1.99mm=A0=A0=A0 =A0=A0=A0 2.16 - 2.26mm ArialSeal2=A0=A0=A0 =A0=A0=A0 =A0=A0=A0= =A0=A0=A0 =A0=A0=A0 =A0=A0=A0 1.98mm=A0=A0=A0 =A0=A0=A0 2.22 - 2.25mm ArialSeal3=A0=A0=A0 =A0=A0=A0 =A0=A0=A0= =A0=A0=A0 =A0=A0=A0 =A0=A0=A0 1.98mm=A0=A0=A0 =A0=A0=A0 2.18 - 2.20mm =A0 ArialClearly the slot is larger at the top - is this due to design or is this due to wear?=A0 Lynn??? Anybody? =A0 ArialIn any case I found the specs for the space left between seal and slot side after you stick an Apex seal in the slot, again in the good rotor (I used a new seal), the max limit permitted (specs) is 0.15mm,=A0 ALL the slots would accept a 0.15mm leaf gauge blade between the seal and top of the apex slot and some would accept a 0.18mm blade.=A0 Clearly at or outside the max limits. =A0 ArialAs I rotated the rotors around their housings before I completely disassembled the engine, I noticed that the apex seals seemed to be leaning quite a bit as they brushed=A0along the housing walls.=A0 I think these measurements = indicate I either got a rotor set =A0that was on its last legs or something cause abnormal wear.=A0 Since the rotors were used, I have no ideal how many miles or how hard the miles may have been.=A0 I have read that apex slots can become worn sufficiently that the apex seal will fold over the edge - and a piece of one apex seal certainly = did. =A0 ArialThe question is did it fold over due to a foreign object first breaking the seal or did the seal break because its center section was encountering increased drag and bending motion compared to its ends?=A0 The ends stayed in = place. =A0 Arial=A0 Upon closer examination it appears there are faint =A0"chatter" marks on the inside of the rotor housings, you can see them visually and when I move my fingers over them I can detect a very faint variation like a wave pattern.=A0=A0 The rotors were used also=A0and =A0I certainly don't recall after 4 years - but they could have been present then.=A0 Fortunately, I do have a set of practically brand new rotor housings - although they are not turbo housings - well, the plus side may be easier to muffler = {:>) =A0 ArialAt this point I am inclined toward new rotors to h___l with the expense.=A0 I'm going to get hemorrhoids if this keeps up {:>).=A0 =A0 ArialJust though you would like to know. =A0 ArialEd =A0 ArialEd Anderson Rv-6A N494BW Rotary Powered Matthews, NC = 1999,1999,FFFFeanderson@carolina.rr.com = --Apple-Mail-2--82851306--