X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-qy0-f204.google.com ([209.85.221.204] verified) by logan.com (CommuniGate Pro SMTP 5.3.4) with ESMTP id 4174584 for flyrotary@lancaironline.net; Mon, 22 Mar 2010 11:44:48 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.221.204; envelope-from=rwstracy@gmail.com Received: by qyk42 with SMTP id 42so3014277qyk.7 for ; Mon, 22 Mar 2010 08:44:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:sender:received:in-reply-to :references:date:x-google-sender-auth:message-id:subject:from:to :content-type; bh=dsZpeLm1Ts7ihUAokjI1KC2E2YIvWByX6i9F+q3oFMc=; b=djw+almVrHMCweB0nGQbFJ2IgAt2Ai2e3HC4FZQbKG3fV732NeHFr8UJW9VSUG1WwF HxfPTwwW5gZ5mf3c5I6vDzB8zl/flv3/42e+dNMfBXlFoMiiG0Km/1KcLNxq5cUqJQUE K/QLXiARBEL2GnS6EDxUrCFnMUWChfE4bA3nU= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:sender:in-reply-to:references:date :x-google-sender-auth:message-id:subject:from:to:content-type; b=rTNQRz87nlWQZukI3RQkeNjeiH5xjLtzPSSjr3kWEQheWgqtV1Q6XsUqomqbqk1Sf1 Ym2JWGQcbZZ5vwml2Cmm4LaKuV3p+8dEOPnF4lDz6Y7kv/vIhk1cDt4kweWMxRHiJXx/ qEECfypl5tpg/CRNSPwBMLXzEW9YTz2Y6ZoPs= MIME-Version: 1.0 Sender: rwstracy@gmail.com Received: by 10.224.83.80 with SMTP id e16mr2321008qal.231.1269272652832; Mon, 22 Mar 2010 08:44:12 -0700 (PDT) In-Reply-To: References: Date: Mon, 22 Mar 2010 11:44:12 -0400 X-Google-Sender-Auth: 83c208e0e86c3bad Message-ID: <1b4b137c1003220844p71b63732ued15278aab4be22c@mail.gmail.com> Subject: Re: [FlyRotary] Re: Fwd: Question on RD2-C From: Tracy Crook To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=000feaf32450985f3004826591db --000feaf32450985f3004826591db Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable Be aware that unless you are fully aware of all the factors involved, it is risky to make off the cuff pronouncements of the best solution. I'll just state one here so that no one goes off on a wrong track. The steel spline and flange on the RD-1 damper is machined from a stock Ford transmission part. This part is manufactured in a sintered powdered metal process that has proven to be more than strong enough. BUT, if the riveting process imposes too much radial force at the outer edge of the flange, it could cause the flange to crack and result in catastrophic failure at some point. Because of this factor, DO NOT rivet it with steel rivets. Mark S. did the right thing and asked about the bolt fix prior to doing it. Al G. has a good point about the scope of the problem. I have over 1200 hours on this design with 13B engines and no sign of this problem. I'm obviously now re-evaluating things with 20B or boosted 13B installations bu= t have not reached any final conclusions. Tracy Crook, RWS On Mon, Mar 22, 2010 at 1:31 AM, Al Gietzen wrote: > Sorry guys my system glitched. I sent the e-mail too soon. An adjustabl= e > reamer is available at most machining supply places. The bolts may be > slightly different, but you can buy a few extra to get some of the same > size. Get some jet nuts or be sure you locktite or safety wire the nuts t= oo. > > Bill Jepson > > Just another view on this; custom fitting and reaming each of 20 holes > individually for the bolts may work for a few individual fixes, but is > certainly not a production solution. Nor do I think safety wiring the 20 > bolts (which are visible) is necessary or practical where metal locknuts > would be perfectly reliable. Cold forming steel rivets are not as strong = as > AN bolts, not definitely more easily adapted to doing very many of these > parts. > > > > But let=92s not get ahead of ourselves. Is this an issue with any urgenc= y? > Does this issue apply to more than a few cases of 3-rotor and turbocharg= ed > 2 rotors? Tracy has what =96 more than 800 hours on one of these drives w= ith > aluminum rivets on a 13B and it=92s still good, so is it a matter of the > number of hours? How many other high hour drives are there that should be > checked. How many hours are on 20B and 13B turbo installations. And wha= t > is the best fix? Certainly Tracy has to have some time to weigh in on > that. > > > > Al G > --000feaf32450985f3004826591db Content-Type: text/html; charset=windows-1252 Content-Transfer-Encoding: quoted-printable Be aware that unless you are fully aware of all the factors involved, it is risky to make off the cuff pronouncements of the best solution.=A0=20 I'll just state one here so that no one goes off on a wrong track.

=A0The steel spline and flange on the RD-1 damper is machined from a stock Ford transmission part.=A0 This part is manufactured in a sintered=A0=20 powdered metal process that has proven to be more than strong enough.=A0=20 BUT, if the riveting process imposes too much radial force at the outer=20 edge of the flange, it could cause the flange to crack and result in=20 catastrophic failure at some point.=A0 Because of this factor, DO NOT=20 rivet it with steel rivets.

Mark S. did the right thing and asked about the bolt fix prior to doing=20 it.

Al G.=A0 has a good point about the scope of the problem.=A0 I have over=20 1200 hours on this design with 13B engines and no sign of this problem.=A0 I'm obviously now re-evaluating things with 20B or boosted 13B=20 installations but have not reached any final conclusions.

Tracy Crook,=A0=A0=A0 RWS

On Mon, Mar 22,= 2010 at 1:31 AM, Al Gietzen <ALVentures@cox.net> wrote:

Sorry guys = my system glitched. I sent the e-mail too soon. An adjustable reamer is available at most machini= ng supply places. The bolts may be slightly different, but you can buy a few e= xtra to get some of the same siz= e. Get some jet nuts or be sure you locktite or safety wire the nuts too.=

Bill Jepson=

Just anoth= er view on this; custom fitting and reaming each of 20 holes individually for the bolts may work fo= r a few individual fixes, but is certainly not a production solution.=A0 Nor do I think safety wiring the 20 bolts (which are visible) is necessary or practical where metal locknuts would be perfectly reliable. Cold forming st= eel rivets are not as strong as AN bolts, not definitely more easily adapted to doing very many of these parts.

=A0=

But let=92= s not get ahead of ourselves.=A0 Is this an issue with any urgency? =A0Does this issue apply to more than a few cases of 3-rotor and turbocharged 2 rotors? Tracy has what =96 more than 800 hours on one of these drives with aluminum rivets on a 13B and it=92s still good, so is it a matter of the number of hours? How many other high h= our drives are there that should be checked.=A0 How many hours are on 20B and 13B turbo installations. =A0And what is the best fix?=A0 Certainly <= /font>Tracy has to have some time to weigh in on that.

=A0=

Al G


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