X-Virus-Scanned: clean according to Sophos on Logan.com X-SpamCatcher-Score: 30 [X] Return-Path: Received: from mail4.qnetau.com ([202.146.213.1] verified) by logan.com (CommuniGate Pro SMTP 5.1.8) with SMTP id 1982190 for flyrotary@lancaironline.net; Thu, 12 Apr 2007 17:13:56 -0400 Received-SPF: none receiver=logan.com; client-ip=202.146.213.1; envelope-from=greg@itmack.com Received: (qmail 84320 invoked by uid 399); 12 Apr 2007 21:13:04 -0000 Received: from unknown (HELO NOTEBOOK) (220.237.95.24) by mail4.qnetau.com with SMTP; 12 Apr 2007 21:13:04 -0000 X-Originating-IP: 220.237.95.24 Message-ID: <007901c77d47$60a785d0$6502a8c0@NOTEBOOK> From: "Greg" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: Mount offset Date: Fri, 13 Apr 2007 07:13:11 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0076_01C77D9B.320E7680" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3028 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3028 X-Antivirus: avast! (VPS 000733-0, 11/04/2007), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. ------=_NextPart_000_0076_01C77D9B.320E7680 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Jerry are you making full engine mounts now? Greg On Apr 12, 2007, at 1:45 AM, WRJJRS@aol.com wrote: Bob, Many use the washers method. Built into the mount would be = best. Better yet a truly clever counter rotating prop set would be = super. Then fin offset could also be zero for max efficiency! Bill Jepson My kit suggest to install washers between my mount and the = firewall to get the thrust I need. This doesnt sound like a very good = way to do it to me. Is this really the norm for adjusting thrust? Bob MearsSupermarine Spitfire =20 -----Original Message----- From: jerryhey@earthlink.net To: flyrotary@lancaironline.net Sent: Wed, 11 Apr 2007 3:22 PM Subject: [FlyRotary] Re: Mount offset Bobby, I am sure we can get it right. I am interested in = Blake's suggestion because I can do the drilling of the S-beam on the = mill where I have more control. We can also do something like you = have just suggested by measuring from a point on the S beam back to the = firewall. And then instead of moving the motor around, I can just = move the firewall. Same thing in reverse. Jerry I have been worrying about accuracy when setting the offset as my = fixture does not have an easy point to measure from. I've considered = a number of schemes in recent weeks. Most would work but they were = not easy to implement. However, the last time the fixture was rebuilt = (when the S-beam was moved to the prop flange a year ago) I did put in = a way to pivot the engine mount at the prop flange but never used it. = All my engine mounts were straight ahead. Off set could be managed = with washers at the firewall. =20 Here is the Dumb part: For at least two years I have used a laser mounted on the fixture = to make sure it was on thrust line. It fires right down the engine = center line to the "firewall" which has its own center line. I can move = the firewall back and forth, side to side, etc. When the laser points = exactly to the firewall center line everything is lined up straight = ahead. To dial in off set, all I had to do was mark the calculated = offset from the center line on the firewall and then pivot the fixture = until the laser pointed to the new mark. Honestly, I did not realize = I could do it this perfectly easy way which I myself built, until a = hour ago. It is now 3:30 am and I can finally get some sleep. Jerry=20 -------------------------------------------------------------------------= --- See what's free at AOL.com. ------=_NextPart_000_0076_01C77D9B.320E7680 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Jerry are you making full engine mounts = now?
 
Greg


On Apr 12, 2007, at 1:45 AM, WRJJRS@aol.com wrote:
Bob, Many=20 use the washers method. Built into the mount would be best. Better = yet a=20 truly clever counter rotating  prop set would be super. Then = fin offset=20 could also be zero for max efficiency!
Bill=20 Jepson
My kit suggest to = install=20 washers between my mount and the firewall to get the thrust I = need. This=20 doesnt sound like a very good way to do it to me. Is this really = the norm=20 for adjusting thrust?
 
Bob=20 Mears
Supermarine=20 Spitfire
 -----Original=20 Message-----
From:=20 jerryhey@earthlink.net<= BR=20 style=3D"FONT-SIZE: 10px; FONT-FAMILY: Verdana">To: flyrotary@lancaironline.netSent: Wed, 11 Apr = 2007 3:22=20 PM
Subject: = [FlyRotary] Re:=20 Mount offset
Bobby,  =  I am sure=20 we can get it right.  I am interested in Blake's suggestion = because I=20 can do the drilling of the S-beam on the mill where I have more = control.=20    We can also do something like you have just suggested = by=20 measuring from a point on the S beam back to the firewall.  =20  And then instead of moving the motor around, I can just move = the=20 firewall.   Same thing in reverse. =20 Jerry
 
I have been worrying = about=20 accuracy when setting the offset as my fixture does not have = an  easy=20 point to measure  from.   I've considered a number = of =20 schemes in recent  weeks.  Most would work but they were = not easy=20 to implement.  However, the last time the fixture was rebuilt = (when the=20 S-beam was moved to the prop flange a year ago)  I did put in a = way to=20 pivot the engine mount at the prop flange but never used it.  =20  All my engine mounts were straight ahead.  Off set  = could be=20 managed with washers at the = firewall.  
Here=20 is the Dumb part:

 For=20 at least two years I have used a laser  mounted on the fixture = to make=20 sure it was  on thrust line. It fires right down the engine = center line=20 to the "firewall" which has its own center line. I can move the = firewall=20 back and forth, side to side, etc.  When the laser points = exactly to=20 the firewall center line everything is lined up straight = ahead. =20  To dial in off set,  all I had to do was  mark the=20 calculated  offset from the center line on the firewall and = then pivot=20 the fixture until the laser pointed to the new mark.  Honestly, =  =20 I  did not realize I could do it this perfectly easy way which = I myself=20 built,  until a hour ago.  It is now 3:30 am and I can = finally get=20 some sleep.   Jerry 
See=20 what's free at AOL.com.

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