X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from fed1rmfepo202.cox.net ([68.230.241.147] verified) by logan.com (CommuniGate Pro SMTP 5.4c2o) with ESMTP id 4885225 for flyrotary@lancaironline.net; Mon, 28 Feb 2011 11:54:43 -0500 Received-SPF: none receiver=logan.com; client-ip=68.230.241.147; envelope-from=alventures@cox.net Received: from fed1rmimpo01.cox.net ([70.169.32.71]) by fed1rmfepo202.cox.net (InterMail vM.8.01.04.00 201-2260-137-20101110) with ESMTP id <20110228165407.HRGV21362.fed1rmfepo202.cox.net@fed1rmimpo01.cox.net> for ; Mon, 28 Feb 2011 11:54:07 -0500 Received: from BigAl ([72.199.216.14]) by fed1rmimpo01.cox.net with bizsmtp id DUu71g00E0KDB3c03Uu7S6; Mon, 28 Feb 2011 11:54:07 -0500 X-VR-Score: -250.00 X-Authority-Analysis: v=1.1 cv=Uf0N7Q8inZd1smlX5QkgY0Nt7egyp8IgCiz8thsnNmI= c=1 sm=1 a=B9PaJCCeMWsA:10 a=TPvrVRyicAsl4VeEYn0L5g==:17 a=Ia-xEzejAAAA:8 a=3oc9M9_CAAAA:8 a=Yud8UEZi1t1t2epVSb4A:9 a=3lpZG1GTBJbogR--XhsA:7 a=eQsfr2WW2_2FVfDzv54NZ40IU4EA:4 a=wPNLvfGTeEIA:10 a=EzXvWhQp4_cA:10 a=U8Ie8EnqySEA:10 a=7ehGrN1VTllzys4c:21 a=D4SDAZJhoPlQ5wKS:21 a=yMhMjlubAAAA:8 a=u5zzhgGq8c0Tz96qSPMA:9 a=DTcnQXx-uhY5bOJlWosA:7 a=PW8JA5chlPZWxnL6MY6YmHTHDi4A:4 a=CrtTE-0sNxaV9cWO:21 a=ZOKEW21enuUvCcrH:21 a=TPvrVRyicAsl4VeEYn0L5g==:117 X-CM-Score: 0.00 Authentication-Results: cox.net; none From: "Al Gietzen" To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] Re: Steve Boese TDC Finder Date: Mon, 28 Feb 2011 08:54:31 -0800 Message-ID: <76510FEFCCF5488C8A67C72E91D29F69@BigAl> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0016_01CBD725.1D4257C0" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.6863 Importance: Normal Thread-Index: AcvXEiDO+24EjFf/QZq2vSUF0j/Z/AAUH+pQ X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5994 In-Reply-To: This is a multi-part message in MIME format. ------=_NextPart_000_0016_01CBD725.1D4257C0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable First let me point out the big error in the procedure I wrote: =20 -The center of the combustion chamber is 60o on the rotor from the tip = seal; or 120o (should read 180) on the E-shaft. - Count the total number of teeth on the ring gear, and divide by 3 = (should read 2). Now rotate the engine by that number of teeth (either = direction) and rotor 1 will be very close to TDC. =20 I wouldn=92t argue the precision of the method; but for the housings you = show, the offset appears to be much less than 10 degrees. The e-shaft TDC = offset would then be 1 =BD times that as you split the difference between the = plugs and multiply by 3:1 ratio. And being a few degrees off on the rotary is = not of much consequence. =20 Ultimately the timing at which we operate is determined by the timing = curve built in to the engine controller. I=92m pretty sure Tracy has modified = that some over the years. And then there in-flight tuning of the timing at cruise condition that you may like to look at. =20 When I got my 20B with a 12A front housing from Atkins, the relationship = of the pointer to the marks on the pulley made no sense. I used my simple method to determine a TDC mark, and worked from there. On the dyno we = put a pressure transducer into a trailing plug hole and adjusted timing a bit while operating (I don=92t recall conditions =96 I think 22=94 MAP) to = get the pressure trace to look right. We chose a point 2 steps retarded on the = EC2, - 3.75o. =20 Subsequently I did some variation at cruise conditions to see effect on performance, and again ended up at two steps of retarding, although I = found performance change almost undetectable over a 3-4 step range (~7o) to = either side. So that setting is pretty consistent with Lynn=92s data that the = method leads to a TDC that was a bit BTDC; but is of no consequence. =20 That=92s my story, and I=92 sticking to it:-). =20 Al=20 =20 =20 =20 =20 -----Original Message----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Steven W. Boese Sent: Sunday, February 27, 2011 10:38 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Steve Boese TDC Finder =20 Al, =20 Depending on exactly which housings you have, that method may be off by = more than 10 degrees. See the attached photo. =20 Steve Boese =20 From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Al Gietzen Sent: Sunday, February 27, 2011 11:30 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Steve Boese TDC Finder =20 Of course there is always the way that doesn=92t require any parts =96 = well; maybe a piece of wire, or something to use as a pointer near the teeth = on the flywheel ring gear. =20 -Remove the rotor 1 spark plugs (and one from rotor 2 to relieve the compression).=20 -Turn the engine until the tip seal on rotor 1 is in the center of the leading plug hole. Mark the gear tooth at the pointer. -Turn the engine until the same tip seal is visible in the trailing plug hole. Mark the tooth at the pointer. -Now turn the engine back to the gear tooth at the pointer that is half = way between the 2 marked. The tip seal is now at TDC. -The center of the combustion chamber is 60o on the rotor from the tip = seal; or 120o on the E-shaft. - Count the total number of teeth on the ring gear, and divide by 3. Now rotate the engine by that number of teeth (either direction) and rotor 1 will be at TDC. =20 Al G =20 -----Original Message----- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Steven W. Boese Sent: Sunday, February 27, 2011 4:10 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Steve Boese TDC Finder =20 I like this better than what I came up with. It will be easier to find = the parts and assembly will also be easier since none of the initial parts = need to be modified. As long as one is careful not to draw the water or oil = into the engine, it will also be easier to use. Although there always seems = to be a better way to do something, this seems as good and simple as it can get. No more excuses for not knowing where TDC is. =20 Steve Boese =20 =20 From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of bktrub@aol.com Sent: Sunday, February 27, 2011 2:35 PM To: Rotary motors in aircraft Subject: [FlyRotary] Re: Steve Boese TDC Finder =20 You can get an air hold, essentially a spark plug hole adapter that goes = on a compressed air hose, for about $6 at NAPA. It's used to hold a valve = in place while you change the valve seals. You can use it to find TDC by putting it in the plug hole, running a tube to it and putting the end = in a jar of water or oil. Turn the engine slowly until the point where the bubbles stop and the water just starts to go up the tube. That's TDC. =20 Brian Trubee =20 -----Original Message----- From: dlomheim@aol.com To: Rotary motors in aircraft Sent: Fri, Feb 25, 2011 8:10 pm Subject: [FlyRotary] Steve Boese TDC Finder Steve: Please don't think your cool invention wasn't appreciated by = those of us at Paduca... I for one grabbed one and plan on using it to find = TDC prior to re-installing my CAS... =20 CYA =20 =20 Doug Lomheim RV-9A ; 13B FWF =20 =20 ------=_NextPart_000_0016_01CBD725.1D4257C0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

First let me point out the big = error in the procedure I wrote:

 

-The center of the combustion chamber is 60o on the rotor = from the tip seal; or 120o= (should read = 180) on the E-shaft.

- Count the total number of teeth on the ring gear, and divide by 3 = (should read 2). Now rotate = the engine by that number of teeth (either direction) and rotor 1 will be = very close to = TDC.

 

I wouldn’t argue the = precision of the method; but for the housings you show, the offset appears to be much = less than 10 degrees. The e-shaft TDC offset would then be 1 =BD times that = as you split the difference between the plugs and multiply by 3:1 ratio. And = being a few degrees off on the rotary is not of much = consequence.

 

Ultimately the timing at which we operate is determined by the timing curve built in to the engine = controller.=A0 I’m pretty sure Tracy has modified that some over the years.=A0 And then there = in-flight tuning of the timing at cruise condition that you may like to look = at.

 

When I got my 20B with a 12A = front housing from Atkins, the relationship of the pointer to the marks on the = pulley made no sense. I used my simple method to determine a TDC mark, and = worked from there.=A0 On the dyno we put a pressure transducer into a trailing plug = hole and adjusted timing a bit while operating (I don’t recall conditions – I = think 22” MAP) to get the pressure trace to look right. We chose a point = 2 steps retarded on the EC2, - 3.75o= .

 

Subsequently I did some variation = at cruise conditions to see effect on performance, and again ended up at = two steps of retarding, although I found performance change almost undetectable = over a 3-4 step range (~7o) to either side. So that setting is pretty consistent with Lynn’s data that the method leads to a TDC that was a bit = BTDC; but is of no consequence.

 

That’s my story, and = I’ sticking to itJ.

 

Al

=A0

 

 

 

-----Original = Message-----
From: Rotary motors in = aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Steven W. Boese
Sent: Sunday, February = 27, 2011 10:38 PM
To: Rotary motors in = aircraft
Subject: [FlyRotary] Re: = Steve Boese TDC Finder

 

Al,

 

Depending on exactly which housings you have, that method may be off by more than = 10 degrees.  See the attached photo.

 

Steve Boese

 

From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Al Gietzen
Sent: Sunday, February = 27, 2011 11:30 PM
To: Rotary motors in = aircraft
Subject: [FlyRotary] Re: = Steve Boese TDC Finder

 

Of course there is always the way that doesn’t require any parts = – well; maybe a piece of wire, or something to use as a pointer near the = teeth on the flywheel ring gear.

 

-Remove the rotor 1 spark plugs (and one from rotor 2 to relieve the = compression).

-Turn the engine until the tip seal on rotor 1 is in the center of the leading = plug hole.  Mark the gear tooth at the pointer.

-Turn the engine until the same tip seal is visible in the trailing plug hole. = Mark the tooth at the pointer.

-Now turn the engine back to the gear tooth at the pointer that is half way = between the 2 marked.  The tip seal is now at TDC.

-The center of the combustion chamber is 60o on the rotor = from the tip seal; or 120o= on the E-shaft.

- Count the total number of teeth on the ring gear, and divide by 3. Now = rotate the engine by that number of teeth (either direction) and rotor 1 will = be at TDC.

 

Al = G

 

-----Original = Message-----
From: Rotary motors in = aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Steven W. Boese
Sent: Sunday, February = 27, 2011 4:10 PM
To: Rotary motors in = aircraft
Subject: [FlyRotary] Re: = Steve Boese TDC Finder

 

I like this better than what I came up with.  It will be easier to find = the parts and assembly will also be easier since none of the initial parts need to = be modified.  As long as one is careful not to draw the water or oil = into the engine, it will also be easier to use.  Although there always seems = to be a better way to do something, this seems as good and simple as it can get.  No more excuses for not knowing where TDC = is.

 

Steve Boese

 

 

From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of bktrub@aol.com
Sent: Sunday, February = 27, 2011 2:35 PM
To: Rotary motors in = aircraft
Subject: [FlyRotary] Re: = Steve Boese TDC Finder

 

You can get an air hold, essentially a spark plug hole adapter that goes on a compressed air hose, for about $6 at NAPA. It's used to hold a valve in = place while you change the valve seals. You can use it to find TDC by putting = it in the plug hole, running a tube  to it and putting the = end in a jar of water or oil. Turn the engine slowly until the point where the = bubbles stop and the water just starts to go up the tube. That's = TDC.

 

Brian Trubee

 

-----Original Message-----
From: dlomheim@aol.com
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Fri, Feb 25, 2011 8:10 pm
Subject: [FlyRotary] Steve Boese TDC Finder

Steve:  Please don't think your cool invention wasn't appreciated by those of us = at Paduca... I for one grabbed one and plan on using it to find TDC prior = to re-installing my CAS...

 

CYA  <= /span>

 

Doug Lomheim

RV-9A ; 13B FWF 

 

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