X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail12.syd.optusnet.com.au ([211.29.132.193] verified) by logan.com (CommuniGate Pro SMTP 5.2.11) with ESMTPS id 3430465 for flyrotary@lancaironline.net; Fri, 16 Jan 2009 20:12:16 -0500 Received-SPF: pass receiver=logan.com; client-ip=211.29.132.193; envelope-from=lendich@optusnet.com.au Received: from george (d211-31-88-81.dsl.nsw.optusnet.com.au [211.31.88.81]) by mail12.syd.optusnet.com.au (8.13.1/8.13.1) with SMTP id n0H1BXGJ032536 for ; Sat, 17 Jan 2009 12:11:34 +1100 Message-ID: <68E6B451753446F8B5968B280809CEBF@george> From: "George Lendich" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: DNA Muffler Date: Sat, 17 Jan 2009 11:11:35 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0007_01C97894.5C644D60" 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 090116-1, 16/01/2009), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. ------=_NextPart_000_0007_01C97894.5C644D60 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Mark, I had a quick look and noticed the parts welded from the outside - very = good I thought. The edges facing down stream will help. I didn't notice = the price, so what price is the Gen 2. My parts cost me about $250 (Aust) and the welding, perhaps $150 (Aust)- = so if your buying it for about $250 US it's a good price. George ( down under) ----- Original Message -----=20 From: Mark Steitle=20 To: Rotary motors in aircraft=20 Sent: Saturday, January 17, 2009 10:51 AM Subject: [FlyRotary] Re: DNA Muffler George,=20 With the edges of each cross bar pointed downstream of the exhaust = flow, I don't see a problem with the heat attacking them. Also, if one = were to somehow break loose, I don't see how it could manage to block = the exit, maybe partially, but not totally. The engine should still run = at reduced power if that were to happen. I would like to special order = one made of 321ss. Also, if you look at the DNA web site, you'll see = that they make a Gen 1 and a Gen II. The Gen II is much stronger as the = cross bars protrude through the can and are welded from the outside. = The Gen I bars are spot welded to the can. The Gen II is also more than = twice the price of the Gen I. =20 Mark S. On Fri, Jan 16, 2009 at 4:10 PM, George Lendich = wrote: 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_0007_01C97894.5C644D60 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Mark,
I had a quick look and noticed the = parts welded=20 from the outside - very good I thought. The edges facing down stream = will help.=20 I didn't notice the price, so what price is the Gen 2.
My parts cost me about $250 (Aust) and = the welding,=20 perhaps $150 (Aust)- so if your buying it for about $250 US it's a good=20 price.
George ( down under)
----- Original Message -----
From:=20 Mark = Steitle=20
Sent: Saturday, January 17, = 2009 10:51=20 AM
Subject: [FlyRotary] Re: DNA=20 Muffler

George,

With the edges of each cross bar = pointed=20 downstream of the exhaust flow, I don't see a problem with the heat = attacking=20 them.  Also, if one were to somehow break loose, I don't see how = it could=20 manage to block the exit, maybe partially, but not totally.  The = engine=20 should still run at reduced power if that were to happen.  I = would like=20 to special order one made of 321ss.  Also, if you look at the DNA = web=20 site, you'll see that they make a Gen 1 and a Gen II.  The Gen II = is much=20 stronger as the cross bars protrude through the can and are welded = from the=20 outside.  The Gen I bars are spot welded to the can.  The = Gen II is=20 also more than twice the price of the Gen I.  

Mark = S.

On Fri, Jan 16, 2009 at 4:10 PM, George = Lendich <lendich@optusnet.com.au>=20 wrote:
Mark,
The heat and pulses attack/ affect = the weakest=20 part of any internal part, a thin edge is the weakest part. You = will=20 notice that I don't expose and edges to the sound wave or hot=20 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=20 than straight bar stock.  Not sure what material the cross=20 bars are made from though.  The p/n 1040 is made to = weld to=20 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=20 any louder than the Hushpower II whose guts are laying = on the=20 hangar floor in a pile of powder and small pieces.  Based = on its=20 short lifespan and the rust-colored debris, I doubt the Hushpower=20 muffler's innards are made of SS.  ;-(
 
Mark

On Fri, Jan 16, 2009 at 10:08 AM, Ed = Anderson <eanderson@carolina.rr.com> = wrote:

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

 

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

 

Ed

 

Ed=20 Anderson

Rv-6A = N494BW=20 Rotary Powered

Matthews,=20 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=20 Steitle
Sent: = Friday,=20 January 16, 2009 9:05 AM


To:=20 Rotary motors in aircraft
Subject: [FlyRotary] DNA=20 Muffler

 

Does anyone on the list have=20 any real-life rotary experience with the DNA Gen II = muffler=20 (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=20 of the muffler body, which is made of 304 SS.  Their web = site=20 claims that the racers use them with great success.  From = speaking=20 with a sales rep, they claim there the rotary crowd uses them = too. =20 I'm considering purchasing one of their FULL THROTTLE COLLECTOR = mufflers=20 (P/N 1040), but thought I would check to see if anyone else = has=20 used this style muffler.  This muffler has a 3" = inlet/outlet with a=20 4" body.  So it is compact enough to fit inside my = cowl. =20 My exhaust header has a 3" swivel joint, so it should be a good=20 fit. 

 

Mark=20 S.



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

The message was = checked by=20 ESET NOD32 Antivirus.

http://www.eset.com

<= /BLOCKQUOTE>

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