X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imf18aec.mail.bellsouth.net ([205.152.59.66] verified) by logan.com (CommuniGate Pro SMTP 5.0c3) with ESMTP id 749503 for flyrotary@lancaironline.net; Tue, 04 Oct 2005 21:31:10 -0400 Received-SPF: pass receiver=logan.com; client-ip=205.152.59.66; envelope-from=bobperk@bellsouth.net Received: from ibm61aec.bellsouth.net ([70.149.129.176]) by imf18aec.mail.bellsouth.net with ESMTP id <20051005013013.DZKA698.imf18aec.mail.bellsouth.net@ibm61aec.bellsouth.net> for ; Tue, 4 Oct 2005 21:30:13 -0400 Received: from HpPavilion310n ([70.149.129.176]) by ibm61aec.bellsouth.net with ESMTP id <20051005013012.CPSA463.ibm61aec.bellsouth.net@HpPavilion310n> for ; Tue, 4 Oct 2005 21:30:12 -0400 From: "Bob Perkinson" To: "Rotary motors in aircraft" Subject: RE: [FlyRotary] Re: Telling rotors apart - Never trust Atkins! Date: Tue, 4 Oct 2005 20:32:13 -0500 Message-ID: MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_018C_01C5C922.B4982CB0" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook IMO, Build 9.0.2416 (9.0.2910.0) X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2600.0000 Importance: Normal In-Reply-To: This is a multi-part message in MIME format. ------=_NextPart_000_018C_01C5C922.B4982CB0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Ok, Georges, found my notes. for the 9.7:1 the depth is 4mm. 9.4:1 is 5.5mm and the 9.1 is 7 mm. Ed OK Ed, I found this in my archives. Bob Perkinson Hendersonville, TN. RV9 N658RP Reserved If nothing changes Nothing changes -----Original Message----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]On Behalf Of David Leonard Sent: Tuesday, October 04, 2005 8:03 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Telling rotors apart - Never trust Atkins! 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 of 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 86-88 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 that 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 balance in my current engine is all SNAFU. Are you sure that system is a valid way to do the measuring? So I just got back from weighing my rotors - Sure enough, the ones Atkins 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 then 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 apart? BTW Ernest, the rotors you sent also weigh in at 10.18. Dave Leonard ------=_NextPart_000_018C_01C5C922.B4982CB0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
 
 
Ok, Georges, found my notes.  for the 9.7:1 the depth is = 4mm. =20 9.4:1  is 5.5mm and the 9.1 is 7 mm.
 
Ed
 
OK Ed, I=20 found this in my archives.

Bob Perkinson
Hendersonville, TN.
RV9 N658RP=20 Reserved
If nothing changes
Nothing = changes
 

-----Original Message-----
From: Rotary motors in = aircraft=20 [mailto:flyrotary@lancaironline.net]On Behalf Of David=20 Leonard
Sent: Tuesday, October 04, 2005 8:03 = PM
To: Rotary=20 motors in aircraft
Subject: [FlyRotary] Re: Telling rotors = apart -=20 Never trust Atkins!

Ed, you are the best.  While you are there see if that magic = book=20 can distinguish between the different front and rear = count-weights.
 
Thanks!

--
Dave Leonard
Turbo Rotary RV-6 = N4VY
http://memb= ers.aol.com/_ht_a/rotaryroster/index.html
http://members= .aol.com/_ht_a/vp4skydoc/index.html=20
 
On 10/4/05, Ed=20 Anderson <eanderson@carolina.rr.com&g= t;=20 wrote:=20
Dave, I am going to have to dig through my = note book=20 out in the workshop.  But,if memory serves me correct, the = 9.7:1=20 measures 4mm from the bottom of a straight edge across the face = (long way)=20 at its deepest part of the compression cavity.
 
Again, I will check my note book and get = back to you=20 but I think the 9.4:1 measured around 5- 5 1/2 mm and the 9.1:1 = measured at=20 7mm.
 
Ed A
----- Original Message ----- =
From: = David = Leonard
To: Rotary = motors in=20 aircraft
Sent: Tuesday, October 04, = 2005 7:21=20 PM
Subject: [FlyRotary] = Telling rotors=20 apart - Never trust Atkins!

 

On 9/28/05, Kelly=20 Troyer <keltro@att.net> wrote:=20
 
  Ed Anderson has a measurement to check the depth of = the=20 combustion depression in the
face of the rotor to determine the compression ratio (the = deeper=20 one is turbo).......
 
How about it Ed, any info on this?  Can it be used to = tell the=20 9.4:1 86-88 rotors from the 9.7:1  rotors?

 Bottom line check weight first then check the depth = of the=20 combustion depression........I have
another way I use to determine what year my rotors are (all = my=20 engines are NA 86 to 91).....The
combustion depression in the 86 to 88 is as cast in the = rotor=20 (slight grainy surface finish).....The
89-91 depression is machined and has straight machine=20 marks.......
 
That is really interesting.  My old rotors are supposed = to be=20 1991 T2 rotors but they have the cast appearance (However since I = got them=20 from Atkins I am not really sure they gave me what they sold = me). =20 The rotors that Earnest sent also have a cast appearance.  = But as I=20 recall, the rotors in the engine I rebuilt had the milling=20 marks...   hmmm..  if that is true the balance in = my=20 current engine is all SNAFU.  Are you sure that system is a = valid way=20 to do the measuring?
 
So I just got back from weighing my rotors - Sure enough, the = ones=20 Atkins sold me weighted in at 10.20 and 10.19 making them the = 86-88=20 variety despite the fact that I paid for a '91 engine.  = Worse, I have=20 no idea what counter-weights he decided to use.  If it = matched the=20 rotors he sold me then I have been running an unbalanced engine = for the=20 last 150 hrs.  (that explains part of why the wife won't fly = in it)=20
 
Does anyone know what the correct weights of the counter = weights=20 should be for a given year group?  Or perhaps some other way = of=20 telling them apart?
 
BTW Ernest, the rotors you sent also weigh in at 10.18.
 
Dave Leonard

 
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