X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: <13brv3@bellsouth.net> Received: from imf24aec.mail.bellsouth.net ([205.152.59.72] verified) by logan.com (CommuniGate Pro SMTP 5.0.6) with ESMTP id 911039 for flyrotary@lancaironline.net; Tue, 03 Jan 2006 07:29:39 -0500 Received-SPF: pass receiver=logan.com; client-ip=205.152.59.72; envelope-from=13brv3@bellsouth.net Received: from ibm59aec.bellsouth.net ([65.6.194.9]) by imf19aec.mail.bellsouth.net with ESMTP id <20060102161518.YMLF6179.imf19aec.mail.bellsouth.net@ibm59aec.bellsouth.net> for ; Mon, 2 Jan 2006 11:15:18 -0500 Received: from rd ([65.6.194.9]) by ibm59aec.bellsouth.net with ESMTP id <20060102161517.VMMH269.ibm59aec.bellsouth.net@rd> for ; Mon, 2 Jan 2006 11:15:17 -0500 From: "Russell Duffy" <13brv3@bellsouth.net> To: "'Rotary motors in aircraft'" Subject: RE: [FlyRotary] Re: Single rotor running- Tracy questions Date: Mon, 2 Jan 2006 10:15:19 -0600 Message-ID: <000001c60fb7$b9e7dd10$6101a8c0@rd> MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0001_01C60F85.6F4FDE10" X-Priority: 3 (Normal) X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook, Build 10.0.6626 Importance: Normal In-Reply-To: X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2527 This is a multi-part message in MIME format. ------=_NextPart_000_0001_01C60F85.6F4FDE10 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable One quick fix is adding a bit of flywheel mass. The race car can idle = right down, RPM wise but with no flywheel, it shakes the trans so hard you = hear it above the considerable exhaust note. So, the idle is set at 2,200 RPM. = Seems real happy there and makes no trans noise. =20 The missing rotor looked like flywheel mass to the system. So removing = it raises the RPM where one of the nodes is peaking.=20 =20 The BD-5 article is a must read for all builders, just to get the hair = on the back of your neck standing up. =20 =20 Bill and Lynn, =20 Thanks for the pointer to the article. Indeed, it's interesting, and = gets your attention. =20 =20 I had wondered if a flywheel of sorts would be needed, but with the high weight of the engine now, I'd hate to add more weight. It would make an interesting test, if I could do it easily though. Perhaps some evenly matched weights could be added at the 4 bolts that hold the flex plate = to the drive plate. I'm not sure if you could put enough weight there to really matter though. =20 =20 This will make a really interesting project, and perhaps another good = use for the dynamic balancing equipment. It's all going to have to wait = until the RV-8 is flying though, because that's my only priority at the = moment. My goal is to have it flying by the end of the Summer, so maybe I can = get back to the single rotor project then. =20 =20 Cheers, Rusty=20 =20 PS- Tracy, can you send me the dimensions and durometer specs for those dampeners? =20 ------=_NextPart_000_0001_01C60F85.6F4FDE10 Content-Type: text/html; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Message
One quick fix is adding a bit of flywheel mass. The race car can = idle right=20 down, RPM wise but with no flywheel, it shakes the trans so hard you = hear it=20 above the considerable exhaust note. So, the idle is set at 2,200 RPM. = Seems=20 real happy there and makes no trans noise.
 
The missing rotor looked like flywheel mass to the system. So = removing it=20 raises the RPM where one of the nodes is peaking.
 
The BD-5 article is a must read for all builders, just to get the = hair on=20 the back of your neck standing up.
 
 
Bill and=20 Lynn,
 
Thanks for the=20 pointer to the article.  Indeed, it's interesting, and gets your=20 attention. 
 
I = had wondered if=20 a flywheel of sorts would be needed, but with the high weight of the = engine now,=20 I'd hate to add more weight.  It would make an interesting test, if = I could=20 do it easily though.  Perhaps some evenly matched weights could be = added at=20 the 4 bolts that hold the flex plate to the drive plate.  I'm not = sure if=20 you could put enough weight there to really matter=20 though.  
 
This will make a=20 really interesting project, and perhaps another good use for=20 the dynamic balancing equipment.  It's all going to have to = wait until=20 the RV-8 is flying though, because that's my only priority at the = moment. =20 My goal is to have it flying by the end of the Summer, so maybe I can = get back=20 to the single rotor project then. 
 
Cheers,
Rusty=20
 
PS- = Tracy, can=20 you send me the dimensions and durometer specs for those=20 dampeners?
 
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