X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from zproxy.gmail.com ([64.233.162.207] verified) by logan.com (CommuniGate Pro SMTP 5.0c3) with ESMTP id 749100 for flyrotary@lancaironline.net; Tue, 04 Oct 2005 21:03:25 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.233.162.207; envelope-from=wdleonard@gmail.com Received: by zproxy.gmail.com with SMTP id p8so23981nzb for ; Tue, 04 Oct 2005 18:02:41 -0700 (PDT) DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com; h=received:message-id:date:from:reply-to:to:subject:in-reply-to:mime-version:content-type:references; b=fVYUmthcd11Ru+pA/Wma0UI9VeYu3IG5bu/Vc0LqYtAdojJrn0miCvtAHJkumljZANd4NqkwUzGI+dpbMAGZJ7Zlbd8xRvI1oFRjlmUxhjlDATC1Zq+R9g0M/I+ul88/xQkoygS2YQFu+H63vLltnS4ptLaX0Kr7C0XPs7X2QMs= Received: by 10.36.250.35 with SMTP id x35mr148846nzh; Tue, 04 Oct 2005 18:02:41 -0700 (PDT) Received: by 10.36.222.6 with HTTP; Tue, 4 Oct 2005 18:02:41 -0700 (PDT) Message-ID: <1c23473f0510041802l6caf4a37k12d05879e2f82d5e@mail.gmail.com> Date: Tue, 4 Oct 2005 18:02:41 -0700 From: David Leonard Reply-To: David Leonard To: Rotary motors in aircraft Subject: Re: [FlyRotary] Re: Telling rotors apart - Never trust Atkins! In-Reply-To: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_5110_28774928.1128474161492" References: ------=_Part_5110_28774928.1128474161492 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Ed, you are the best. While you are there see if that magic book can distinguish between the different front and rear count-weights. Thanks! -- Dave Leonard Turbo Rotary RV-6 N4VY http://members.aol.com/_ht_a/rotaryroster/index.html http://members.aol.com/_ht_a/vp4skydoc/index.html On 10/4/05, Ed Anderson wrote: > > Dave, I am going to have to dig through my note book out in the workshop. > But,if memory serves me correct, the 9.7:1 measures 4mm from the bottom o= f > a straight edge across the face (long way) at its deepest part of the > compression cavity. > Again, I will check my note book and get back to you but I think the 9.4= :1 > measured around 5- 5 1/2 mm and the 9.1:1 measured at 7mm. > Ed A > > ----- Original Message ----- > *From:* David Leonard > *To:* Rotary motors in aircraft > *Sent:* Tuesday, October 04, 2005 7:21 PM > *Subject:* [FlyRotary] Telling rotors apart - Never trust Atkins! > > > On 9/28/05, Kelly Troyer wrote: > > > > Ed Anderson has a measurement to check the depth of the combustion > > depression in the > > face of the rotor to determine the compression ratio (the deeper one is > > turbo)....... > > > How about it Ed, any info on this? Can it be used to tell the 9.4:1 86-8= 8 > rotors from the 9.7:1 rotors? > > Bottom line check weight first then check the depth of the combustion > > depression........I have > > another way I use to determine what year my rotors are (all my engines > > are NA 86 to 91).....The > > combustion depression in the 86 to 88 is as cast in the rotor (slight > > grainy surface finish).....The > > 89-91 depression is machined and has straight machine marks....... > > > That is really interesting. My old rotors are supposed to be 1991 T2 > rotors but they have the cast appearance (However since I got them from > Atkins I am not really sure they gave me what they sold me). The rotors t= hat > Earnest sent also have a cast appearance. But as I recall, the rotors in = the > engine I rebuilt had the milling marks... hmmm.. if that is true the bala= nce > in my current engine is all SNAFU. Are you sure that system is a valid wa= y > to do the measuring? > So I just got back from weighing my rotors - Sure enough, the ones Atkin= s > sold me weighted in at 10.20 and 10.19 making them the 86-88 variety > despite the fact that I paid for a '91 engine. Worse, I have no idea what > counter-weights he decided to use. If it matched the rotors he sold me th= en > I have been running an unbalanced engine for the last 150 hrs. (that > explains part of why the wife won't fly in it) > Does anyone know what the correct weights of the counter weights should > be for a given year group? Or perhaps some other way of telling them apar= t? > BTW Ernest, the rotors you sent also weigh in at 10.18. > Dave Leonard > > > > ------=_Part_5110_28774928.1128474161492 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Content-Disposition: inline
Ed, you are the best.  While you are there see if that magic book= can distinguish between the different front and rear count-weights.
 
On 10/4/05, = Ed Anderson <eanderson@= carolina.rr.com> wrote:
Dave, I am going to have to dig through my note b= ook out in the workshop.  But,if memory serves me correct, the 9.7:1 m= easures 4mm from the bottom of a straight edge across the face (long way) a= t its deepest part of the compression cavity.
 
Again, I will check my note book and get back to = you but I think the 9.4:1 measured around 5- 5 1/2 mm and the 9.1:1 measure= d at 7mm.
 
Ed A
----- Original Message -----
Sent: Tuesday, October 04, 2005 7:21= PM
Subject: [FlyRotary] Telling rotors = apart - Never trust Atkins!

 

On 9/28/05, = Kelly Troyer <keltro@att.net&g= t; wrote:=20
 
  Ed Anderson has a measurement to check the depth of the combust= ion depression in the
face of the rotor to determine the compression ratio (the deeper one i= s turbo).......
 
How about it Ed, any info on this?  Can it be used to tell the 9.= 4:1 86-88 rotors from the 9.7:1  rotors?

 Bottom line check weight first then check the depth of the combu= stion depression........I have
another way I use to determine what year my rotors are (all my engines= are NA 86 to 91).....The
combustion depression in the 86 to 88 is as cast in the rotor (slight = grainy surface finish).....The
89-91 depression is machined and has straight machine marks.......
 
That is really interesting.  My old rotors are supposed to be 199= 1 T2 rotors but they have the cast appearance (However since I got them fro= m Atkins I am not really sure they gave me what they sold me).  The ro= tors that Earnest sent also have a cast appearance.  But as I recall, = the rotors in the engine I rebuilt had the milling marks...   hmm= m..  if that is true the balance in my current engine is all SNAFU.&nb= sp; Are you sure that system is a valid way to do the measuring?=20
 
So I just got back from weighing my rotors - Sure enough, the ones Atk= ins sold me weighted in at 10.20 and 10.19 making them the 86-88 variety de= spite the fact that I paid for a '91 engine.  Worse, I have no idea wh= at counter-weights he decided to use.  If it matched the rotors he sol= d me then I have been running an unbalanced engine for the last 150 hrs.&nb= sp; (that explains part of why the wife won't fly in it)=20
 
Does anyone know what the correct weights of the counter weights shoul= d be for a given year group?  Or perhaps some other way of telling the= m apart?
 
BTW Ernest, the rotors you sent also weigh in at 10.18.
 
Dave Leonard

=
 
------=_Part_5110_28774928.1128474161492--