X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail03.syd.optusnet.com.au ([211.29.132.184] verified) by logan.com (CommuniGate Pro SMTP 5.2.0) with ESMTPS id 2786402 for flyrotary@lancaironline.net; Tue, 11 Mar 2008 03:13:36 -0400 Received-SPF: pass receiver=logan.com; client-ip=211.29.132.184; envelope-from=lendich@optusnet.com.au Received: from george (d220-237-229-11.dsl.nsw.optusnet.com.au [220.237.229.11]) by mail03.syd.optusnet.com.au (8.13.1/8.13.1) with SMTP id m2B7Cn2s031079 for ; Tue, 11 Mar 2008 18:12:50 +1100 Message-ID: <001801c88347$52c5f1c0$0be5eddc@george> From: "George Lendich" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: direct drive- was Re: Anyone have an RD-1C for sale? Date: Tue, 11 Mar 2008 17:12:51 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0015_01C8839B.234345C0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-Antivirus: avast! (VPS 0657-0, 12/12/2006), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. ------=_NextPart_000_0015_01C8839B.234345C0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable The thrust bearing would need to be a multiple layer plain bearing for = thrust and drag. A doubled (at least thrust plate). A bending load on = the taper of the crank would soon have you driving the prop with just = the alignment key, as the counter weight is quite soft and the taper = would let go. An outboard bearing would eliminate that = problem...........=20 And provide a place for some real thrust bearings eliminating the = plain bearings. In fact you could use one of Tracy's reduction units = without the guts. Then you can put the guts in the redrive. And test = back to back outcomes. I saw some huge ducted fan models last weekend = going like rockets. Motors turning up 50,000 RPM. I think it will work. Lynn E. Hanover Lynn, That would be my take on it as well, a properly engineered shaft and = bearings without the planetary. Although it would be a pretty small prop = running at 3,000 to 5,000 RPM. The efficiency of the prop would be well = down as well as the HP and Torque. A PP with high compression rotor = would off-set some losses. Anything can be done. George (down under) ------=_NextPart_000_0015_01C8839B.234345C0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

 
The thrust bearing would need to be a multiple layer plain = bearing for=20 thrust and drag. A doubled (at least thrust plate). A bending load on = the=20 taper of the crank would soon have you driving the prop with just the=20 alignment key, as the counter weight is quite soft and the taper would = let go.=20 An outboard bearing would eliminate that problem...........
 
And provide a place for some real thrust bearings eliminating the = plain=20 bearings. In fact you could use one of Tracy's reduction units without = the=20 guts. Then you can put the guts in the redrive. And test back to = back=20 outcomes. I saw some huge ducted fan models last weekend going = like=20 rockets. Motors turning up 50,000 RPM.
I think it will work.
 
Lynn E. Hanover
 
Lynn,
That would be my take on it as well, a properly = engineered shaft=20 and bearings without the planetary. Although it would be a pretty = small prop=20 running at 3,000 to 5,000 RPM. The efficiency of the prop would be = well down=20 as well as the HP and Torque. A PP with high compression rotor would = off-set=20 some losses.
Anything can be done.
George (down under)
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