X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail01.syd.optusnet.com.au ([211.29.132.182] verified) by logan.com (CommuniGate Pro SMTP 5.2.11) with ESMTPS id 3430255 for flyrotary@lancaironline.net; Fri, 16 Jan 2009 17:11:11 -0500 Received-SPF: pass receiver=logan.com; client-ip=211.29.132.182; envelope-from=lendich@optusnet.com.au Received: from george (d211-31-88-81.dsl.nsw.optusnet.com.au [211.31.88.81]) by mail01.syd.optusnet.com.au (8.13.1/8.13.1) with SMTP id n0GMAR7M002111 for ; Sat, 17 Jan 2009 09:10:29 +1100 Message-ID: <0EAA2D4A1BF74863A3784588BA343600@george> From: "George Lendich" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: DNA Muffler Date: Sat, 17 Jan 2009 08:10:30 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_004B_01C9787B.1000ACC0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5512 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 X-Antivirus: avast! (VPS 090116-0, 16/01/2009), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. ------=_NextPart_000_004B_01C9787B.1000ACC0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Mark, The heat and pulses attack/ affect the weakest part of any internal = part, a thin edge is the weakest part. You will notice that I don't = expose and edges to the sound wave or hot gases. George ( down under) Ed,=20 That is exactly what I was concerned about too. But if you look = closely, you can see that the bars are made of 90* angle. That should = make them much stronger than straight bar stock. Not sure what material = the cross bars are made from though. The p/n 1040 is made to weld to a = header/collector and they claim it is good for up to 1000hp. =20 I have gone ahead and ordered one. I figure it couldn't be any louder = than the Hushpower II whose guts are laying on the hangar floor in a = pile of powder and small pieces. Based on its short lifespan and the = rust-colored debris, I doubt the Hushpower muffler's innards are made of = SS. ;-( Mark On Fri, Jan 16, 2009 at 10:08 AM, Ed Anderson = wrote: Appears somewhat similar in concept to the SpinTech muffler using = baffles/ladders to break up the sound wave front. The thing I would = wonder about is whether those ladders which appears to stretch across = the diameter of the tube could withstand the pulse pounding from the = rotor. My experience with the turbo 13B (with no exhaust splitters) = would indicate it might not long withstand that pounding. But, I could = be wrong about that. Guess you're going to have to buy one and let the rest of us know, = Mark. Ed Ed Anderson Rv-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com http://www.andersonee.com http://members.cox.net/rogersda/rotary/configs.htm#N494BW http://www.dmack.net/mazda/index.html -------------------------------------------------------------------------= --- From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] = On Behalf Of Mark Steitle Sent: Friday, January 16, 2009 9:05 AM To: Rotary motors in aircraft Subject: [FlyRotary] DNA Muffler Does anyone on the list have any real-life rotary experience with = the DNA Gen II muffler (http://www.dnamufflers.com/DNA/main_DNA.html)? = It is an interesting design in that it has no packing material to burn = out. Instead, it utilizes ladder-rungs, which they call "internal sound = diffusers", which resemble a chain of DNA down through the center of the = muffler body, which is made of 304 SS. Their web site claims that the = racers use them with great success. From speaking with a sales rep, = they claim there the rotary crowd uses them too. I'm considering = purchasing one of their FULL THROTTLE COLLECTOR mufflers (P/N 1040), but = thought I would check to see if anyone else has used this style muffler. = This muffler has a 3" inlet/outlet with a 4" body. So it is compact = enough to fit inside my cowl. My exhaust header has a 3" swivel joint, = so it should be a good fit. =20 Mark S. __________ Information from ESET NOD32 Antivirus, version of virus = signature database 3267 (20080714) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com ------=_NextPart_000_004B_01C9787B.1000ACC0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Mark,
The heat and pulses attack/ affect the = weakest part=20 of any internal part, a thin edge is the weakest part. You will = notice that=20 I don't expose and edges to the sound wave or hot = gases.
George ( down under)
Ed,
 
That is exactly what I was concerned about too.  But if you = look=20 closely, you can see that the bars are made=20 of 90* angle.  That should make them much stronger = than=20 straight bar stock.  Not sure what material the cross = bars are made=20 from though.  The p/n 1040 is made to weld to a = header/collector=20 and they claim it is good for up to 1000hp.  =   
 
I have gone ahead and ordered one.  I figure it couldn't be=20 any louder than the Hushpower II whose guts are laying on = the hangar=20 floor in a pile of powder and small pieces.  Based on its = short=20 lifespan and the rust-colored debris, I doubt the Hushpower muffler's = innards=20 are made of SS.  ;-(
 
Mark

On Fri, Jan 16, 2009 at 10:08 AM, Ed Anderson = <eanderson@carolina.rr.com&g= t;=20 wrote:

Appears = somewhat=20 similar in concept to the SpinTech muffler using baffles/ladders to = break up=20 the sound wave front.  The thing I would wonder about is = whether those=20 ladders which appears to stretch across the diameter of the tube = could=20 withstand the pulse pounding from the rotor.  My experience = with the=20 turbo 13B (with no exhaust splitters) would indicate it might not = long=20 withstand that pounding.  But, I could be wrong about=20 that.

 

Guess = you're going=20 to have to buy one and let the rest of us know, = Mark.

 

Ed

 

Ed=20 Anderson

Rv-6A = N494BW Rotary=20 Powered

Matthews, = NC

eanderson@carolina.rr.com

http://www.andersonee.com

http://members.cox.net/rogersda/rotary/configs.htm#N494BW

http://www.dmack.net/mazda/index.html<= FONT=20 face=3DArial size=3D2>

From:=20 Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Mark = Steitle
Sent: Friday, January 16, = 2009 9:05=20 AM
To: Rotary = motors in=20 aircraft
Subject: = [FlyRotary] DNA Muffler

 

Does=20 anyone on the list have any real-life rotary experience=20 with the DNA Gen II muffler (http://www.dnamufflers.com/DNA/main_DNA.html)?  It = is an=20 interesting design in that it has no packing material to burn = out. =20 Instead, it utilizes ladder-rungs, which they call "internal sound=20 diffusers", which resemble a chain of DNA down through the = center of=20 the muffler body, which is made of 304 SS.  Their web site = claims that=20 the racers use them with great success.  From speaking with a = sales=20 rep, they claim there the rotary crowd uses them too.  I'm = considering=20 purchasing one of their FULL THROTTLE COLLECTOR mufflers (P/N 1040), = but=20 thought I would check to see if anyone else has used this style = muffler.  This muffler has a 3" inlet/outlet with a 4" = body.  So=20 it is compact enough to fit inside my cowl.  My exhaust = header has=20 a 3" swivel joint, so it should be a good fit. =20

 

Mark=20 S.



__________ Information = from=20 ESET NOD32 Antivirus, version of virus signature database 3267 = (20080714)=20 __________

The message was checked by ESET NOD32 = Antivirus.

http://www.eset.com

<= /BLOCKQUOTE> ------=_NextPart_000_004B_01C9787B.1000ACC0--