X-Virus-Scanned: clean according to Sophos on Logan.com X-SpamCatcher-Score: 2 [X] Return-Path: Received: from elasmtp-mealy.atl.sa.earthlink.net ([209.86.89.69] verified) by logan.com (CommuniGate Pro SMTP 5.1.8) with ESMTP id 1980598 for flyrotary@lancaironline.net; Wed, 11 Apr 2007 21:55:25 -0400 Received-SPF: none receiver=logan.com; client-ip=209.86.89.69; envelope-from=Dastaten@earthlink.net Received: from [69.91.63.162] (helo=[192.168.1.100]) by elasmtp-mealy.atl.sa.earthlink.net with asmtp (Exim 4.34) id 1HboWF-0008Me-3u for flyrotary@lancaironline.net; Wed, 11 Apr 2007 21:54:39 -0400 Message-ID: <461D912D.8080903@earthlink.net> Date: Wed, 11 Apr 2007 20:53:49 -0500 From: David Staten User-Agent: Mozilla Thunderbird 1.0.7 (Windows/20050923) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Rotary motors in aircraft Subject: Re: [FlyRotary] Re: Mount offset References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-ELNK-Trace: 9a30bff84e6cb88f95c85d38d22416599ef193a6bfc3dd482c18a1638c796ef4bbf29f02787ebee2e925a8e63659b694350badd9bab72f9c350badd9bab72f9c X-Originating-IP: 69.91.63.162 Its the easiest.. (washers) And its the easiest one to adjust (if needed) Dave bmears9413@aol.com wrote: > 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 Mears > Supermarine Spitfire > > -----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 > > > On Apr 11, 2007, at 5:05 PM, Bobby J. Hughes wrote: > >> >> >>> Your correct Ernest. I should have specified an RV. I think all >>> of the >>> RV's are designed the same. I have read somewhere it is 1.25 >>> degrees. >>> Just trying to confirm. >>> >>> Bobby >>> >>> The direction of the engine offset, and any fin offset would also >>> depend on the direction of propeller rotation. The fin and engine >>> offset must agree. >>> >>> >>> Lynn E. Hanover >> >> >> Also, you might ask your engine mount builder if he can truly >> resolve a quarter of a degree. I am sure he is pondering this >> issue and wondering the same :) Jerry >> >>> My simple (hanger engineering) approach would be to draw a straight >>> line the length of the left side tubes. This should be a known >>> length. Then using a protractor draw another line the same length at >>> a 1.25 degree offset. Measure the difference at the end of the >>> lines. Then draw a line 47.5 inches (firewall to C-drive face) and >>> repeat with a 1.25 degree offset. Measure the difference and >>> subtract first set of measurements. That should provide a good >>> estimate for how much shorter to make the right side tubes. Washers >>> could be use for fine tuning if needed. The flying RV10's seem to be >>> as much as 1/2 ball out to the right in cruse. Not sure how much it >>> would be without the offset. It does vary with airspeed. Some are >>> installing rudder trim. Van's mounts have the offset build in. >>> Tracy also has offset built into his RV8 mount. I think it is needed >>> to make the plane fly correctly. >>> >>> Bobby >>> >>> >>> >>> ------------------------------------------------------------------------ >>> See what's free at AOL.com >>> . >> >> > > = > ------------------------------------------------------------------------ > AOL now offers free email to everyone. Find out more about what's free > from AOL at *AOL.com* .