X-Junk-Score: 0 [] X-Cloudmark-Score: 0 [] X-Cloudmark-Analysis: v=2.3 cv=WeVylHpX c=1 sm=1 tr=0 a=GXSWpCAE9/1CVrxg8/o4vw==:117 a=hgd9Fbv9zUJYmKSJFKl7lQ==:17 a=jpOVt7BSZ2e4Z31A5e1TngXxSK0=:19 a=x7bEGLp0ZPQA:10 a=K7ySfSCCDxUA:10 a=pxVhFHJ0LMsA:10 a=ayC55rCoAAAA:8 a=Ia-xEzejAAAA:8 a=pGLkceISAAAA:8 a=LQchsGqtWjE3DhOHKrQA:9 a=aVt9KDfNQw8v9Ayu:21 a=jH2yi2MlFgKRGdPC:21 a=QEXdDO2ut3YA:10 a=S0wkRrzPavQA:10 a=4PR2P7QzAAAA:8 a=n4_vE90PCHVdt5xePEsA:9 a=WjBtHQ06Su0MryJ2:21 a=YX5eyb7lpxlVK02p:21 a=dH6ZfDoHiZ1PrYI-:21 a=frz4AuCg-hUA:10 a=B_RyunTPg8udlmYm5Cu2:22 a=Urk15JJjZg1Xo0ryW_k8:22 a=4dqwQCo7Po2mVW515mGf:22 From: "Matt Boiteau mattboiteau@gmail.com" Received: from mail-qk1-f175.google.com ([209.85.222.175] verified) by logan.com (CommuniGate Pro SMTP 6.2.14) with ESMTPS id 13319767 for flyrotary@lancaironline.net; Thu, 19 Dec 2019 22:23:51 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.85.222.175; envelope-from=mattboiteau@gmail.com Received: by mail-qk1-f175.google.com with SMTP id z76so6874577qka.2 for ; Thu, 19 Dec 2019 19:23:53 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:date:message-id:subject:from:to:in-reply-to:references :user-agent; bh=ueQeN1ZYi8fyq5jCDgl2Bp/F/w5YEgmC4wjjBTAmXnc=; b=FACfUh0sfj0uDNSjzOWtoRwLCDXJL8Ijyy1eBNM9PmanWXY3auCPDO9L5yl6rnVaTm F+ohIZEIn4DKER1vHzNOLTSwy5Y6iHJyufux7fuHIEVhEL/e/+V5H+GzzJtx4NB0/jjH sgPJ/KFIJcKOTo7PI9+DwmQBEO3BzPrnouBgWB0rt/EFIyOfagYfGVIqWmylAqEm9Mdx rjEeTcfmCIRBOhYJ8B65cQSaSREiej6nCIUNZycSLHfNFvZ0TejLqXYFgqmxFTalQnqZ r/j9++k3gwJl4VXWOHHU2WTfzRiLOOL79kR4a+7Vr/pVrKevFzr3p6r/9UTZS1vAyimq gq7w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:date:message-id:subject:from:to :in-reply-to:references:user-agent; bh=ueQeN1ZYi8fyq5jCDgl2Bp/F/w5YEgmC4wjjBTAmXnc=; b=PnoxA0luA+ySsizEqP1SNl4j7JDD5zSK3TYLf6TEkR7MFifehCFI6teUdIAVEgpKth 1D/WSjo1dW8i2MjK4BfhWaLoSgcP221KmNwgOFraZ1ge3qm4nez20z8B4S5L1c96rfys LioQSVFWciN1gPJt6EPIHdPnM4VDYdeSfScagOFZcA0zrhaYQjl+rEQCAcTEzVx07ygs MmuVMxROUY1yFXVaT2JEZvwG8gbQV3/dH2cXdCzmmYdX7lhfAVRPUp5/LHG3m1A954if Toj7PMt4AMyhyNpqDdhsktn48ny8Gcvp6u5B++2an47qjCgwPgNpO0XFTwZKRNjsAyER SZmA== X-Gm-Message-State: APjAAAWRLJIDI6kYsXc48PQm5clPNRXVC3V2lkgqypB6/vD+zRc+1Xep Slm/6Rtw5PFtzkMOWLCP2eCvIoCh7NM= X-Google-Smtp-Source: APXvYqxWAtM8KUr3sX5+SLO9iuFcnhrXmqifBAEsWHCOW06kp0ubqxSQrcDZ8bS0+4BSyon95K+oNg== X-Received: by 2002:a05:620a:2041:: with SMTP id d1mr11646560qka.113.1576812215247; Thu, 19 Dec 2019 19:23:35 -0800 (PST) Return-Path: Received: from [192.168.0.134] ([67.58.218.7]) by smtp.gmail.com with ESMTPSA id r37sm2629453qtj.44.2019.12.19.19.23.34 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 19 Dec 2019 19:23:34 -0800 (PST) Content-Type: multipart/alternative; boundary="----=_NextPart_16223188.940358931015" MIME-Version: 1.0 Date: Thu, 19 Dec 2019 22:23:33 -0500 Message-ID: <8dfa6ad8-8cde-406a-933b-e62d5480bab1@getmailbird.com> Subject: Re: [FlyRotary] Re: Mufflers To: "Charlie England ceengland7@gmail.com" In-Reply-To: References: User-Agent: Mailbird/2.5.43.0 X-Mailbird-ID: 8dfa6ad8-8cde-406a-933b-e62d5480bab1@getmailbird.com ------=_NextPart_16223188.940358931015 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Anyone have a good source (USA side) for 321 tubing? Looking to rebuild a n= ew exhaust like=C2=A0Gary Schwarz. 4" or 5" in size. I've only found one pl= ace SPD Exhaust, that is $130 a foot for 4inch tube. - Matt Boiteau On 2019-11-26 10:37:22 AM, eanderson@carolina.rr.com wrote: Interesting idea about the diagonal placement of the discs, Charlie.=C2=A0 = When a disc did break loose from the jam nuts and spung, it really restrict= ed gas flow, so I think welding the disc in place is likely the best soluti= on. =C2=A0 I think your idea about diagonl slots would be worth trying.=C2=A0 I= t may be that simply cutting say 1/4 - 1/3 of the disc off for gas flow and= then alternating the side of the tube with the slot in it would still caus= e the shock wave to see a solid wall=C2=A0 bounce back and forth between di= sc (mostly) and still permit good gas flow.=C2=A0=C2=A0 Apparently the reduction of the shock wave in the several sections did not = result in the loss you mention due to refledted shock wave.=C2=A0=C2=A0 You and Tupper have a great Thanksgiving.=C2=A0 Ed ------ Original Message ------ From: "Charlie England ceengland7@gmail.com [mailto:ceengland7@gmail.com]" = To: "Rotary motors in aircraft" Sent: 11/24/2019 2:48:50 PM Subject: [FlyRotary] Re: Mufflers Ed, I really wish I'd had a chance to hear those mufflers; I've been fascin= ated by the idea since you first mentioned it many years ago. Do you rememb= er what you were running before, and how much takeoff rpm you gained when y= ou made the switch? With only 5 washers, I wonder if the same effect could be achieved using ha= lf-discs slid into diagonal slots cut in the tube and then welded around th= e cut. Cuts could be staggered in rotation around the tube as you move down= the tube. Would likely need to 'break' the straight edge of the half-disc = to resist fatigue. Small hole at the edge of the cut would allow the 'break= ' to slide into the gap. I would have expected at least some power loss on a 13B because of the detu= ning effect of a mis-timed reflected shock wave; good to hear that it didn'= t. With a Renesis and no intake/exhaust overlap, it shouldn't make much if = any difference to power as long as back pressure is managed with a large pi= pe. Charlie On 11/24/2019 11:48 AM, eanderson@carolina.rr.com [mailto:eanderson@carolin= a.rr.com] wrote: Sorry, Neil, Been a while, it was two exhaust pipes, one for each exhaust port.=C2=A0 Mi= styped, error on the drawing the disc were 2 1/2" dia inside a 2 1/2" dia p= ipe.=C2=A0 The discs fit snugg enough that when one broke loose and spun on= the rod,=C2=A0 it scored the inside of the exhaust tube.=C2=A0 I got the d= iscs from McMaster Carr.=C2=A0 Try oversize SS washers.=C2=A0 =C2=A0The tub= es were actually glass pack mufflers which had 2" dia inlet/outlet.=C2=A0 I= cut the front off and then after inserting the discs use wide metal clamps= to put the tube back together (welding would of course have been better). I do not believe that any of the dimensions are critical except the discs s= hould fit touching the inside of the tube if possible.=C2=A0 I called them = discs but they were actually oversize SS washers with a hole in the center = for the rod.=C2=A0 I ended up with 5 discs inside each tube.=C2=A0 I used t= he spacing for the shorter 36" long tube.=C2=A0 The idea was to have a larg= e portion of the shock wave dissipated inside each segment of the tube whil= e keep the gas flowing freely.=C2=A0=C2=A0 It was truly quite and like I mentioned I could get 6000 rpm with my 13B on= take off.=C2=A0 Large diameter tube/discs would likely permit more/easier = gas flow, but since I can not weld, just finally gave up and went on to oth= er things. Ed =C2=A0 ------ Original Message ------ From: "Neil Unger 12348ung@gmail.com [mailto:12348ung@gmail.com]" To: "Rotary motors in aircraft" Sent: 11/23/2019 10:35:27 PM Subject: [FlyRotary] Re: Mufflers Ed, =C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2=A0=C2= =A0=C2=A0=C2=A0=C2=A0=C2=A0 On rereading your post, am I correct in believi= ng that you had one pipe per exhaust?=C2=A0 A total of 2 pipes?=C2=A0 How m= any discs were in each pipe?=C2=A0 I may have misunderstood, but you say yo= u had a 2.5 inch disc fitted inside a 2 .125" exhaust pipe.=C2=A0 If correc= t measurement how did you manage to force 2.5 " inside=C2=A0 2.125" pipe?= =C2=A0 perhaps the other way around measurement wise?=C2=A0 Thanks,=C2=A0 Neil. On 11/21/2019 3:08 AM, eanderson@carolina.rr.com [mailto:eanderson@carolina= .rr.com] wrote: Given the recent interest in mufflers, I thought I would throw in my experi= ence with home made muffer.=C2=A0 I could hit 6000 rpm on take off with my= =C2=A0 13B with the 2.18:1 Gear ratio.=C2=A0 You could stand within a wing = width with the engine idling and bearly hear it.=C2=A0 At 6000 rpm it was a= bout 1/2 as loud as an unmufflered lycoming.=C2=A0=C2=A0 The basic idea was to break up the shock wave while minimizing gas flow imp= edeance.=C2=A0 I used 1/8" thick 2"1 /2 Dia stainless steel disc inside of = a 2 1/8" dia stainless steel tube.=C2=A0 The disc has slits cut from the ou= ter edge approx 1/2" toward the center in 8 regions as shown in the diagram= .=C2=A0 Then each "tab" was twised 45 deg from the plane of the disc.=C2=A0= If you looked at the disc front on it look almost as a solid disc with jus= t a small slot area showing through.=C2=A0 The idea was that the shock wave= would basically see a "solid or mostly solid" disc where as the gas could = still flow through the slots around the tabs.=C2=A0 I had a threaded rod ex= tending the length of the tube with jam nuts on each side to hold the disc = in place. The reason for the rod and nuts was not being a welder-=C2=A0 I used jam nu= ts - welding it turns out would have been much better as the nuts eventuall= y became loose.=C2=A0 That was not good, when one of the disc came lose it = started to spin and greatly=C2=A0 impeded the gas flow.=C2=A0 =C2=A0Althoug= h folks told me it sound cool - like a turbin winding up. In any case, I decided that not being a welder there was no way I could rem= edy the defects.=C2=A0 I think if there were some way to "spot weld" the ou= ter part of the tabs to the tube and perhas to a rod in the center the muff= ler would have extend it useful time.=C2=A0 I flew approx 12 hours=C2=A0 including one trip to Tracy Crook (first extended flight with muffler) by t= he time I got there at least one disc had broken loose and was spinning.=C2= =A0 Tracy was kind enough to use his welding skills to weld the discs to th= e rod on one of the mufflers (had two one for each exhaust), but within ano= ther 6 hours or so disc in the other muffler started to spin.=C2=A0 Also I = found that the shock wave pounding eventual would break off a tab or two si= nce they were not anchored and could flex. Just thought I would throw the idea out there in case it has any merit. Best Regards Ed ------=_NextPart_16223188.940358931015 Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable
=0A Anyone have = a good source (USA side) for 321 tubing? Looking to rebuild a new exhaust l= ike Gary Schwarz. 4" or 5" in size. I've only found= one place SPD Exhaust, that is $130 a foot for 4inch tube.

=
- Matt Boiteau
=0A =
=0A

On 2019-11-26 10:37:22 AM, eander= son@carolina.rr.com <flyrotary@lancaironline.net> wrote:

Interesting idea about th= e diagonal placement of the discs, Charlie.  When a disc did break loo= se from the jam nuts and spung, it really restricted gas flow, so I think w= elding the disc in place is likely the best solution.

<= div>  I think your idea about diagonl slots would be worth trying.&nbs= p; It may be that simply cutting say 1/4 - 1/3 of the disc off for gas flow= and then alternating the side of the tube with the slot in it would still = cause the shock wave to see a solid wall  bounce back and forth betwee= n disc (mostly) and still permit good gas flow.  

<= /div>
Apparently the reduction of the shock wave in the several section= s did not result in the loss you mention due to refledted shock wave. =  

You and Tupper have a great Thanksgiving.&n= bsp;

Ed
=0A

=0A
------ Orig= inal Message ------
=0A=0A
To:= "Rotary motors in aircraft" <flyrotary@lancaironline.net>
=0A
Sent: 11/24/2019 2:48= :50 PM
=0A
Subject: [FlyRotary] Re: Mufflers

= =0A
=0A=0A
Ed, I really wish I'd h= ad a chance to=0A hear those mufflers; I've been fascinated by the ide= a since you=0A first mentioned it many years ago. Do you remember what= you were=0A running before, and how much takeoff rpm you gained when = you made=0A the switch?
=0A
=0A With only 5 washers, = I wonder if the same effect could be achieved=0A using half-discs slid= into diagonal slots cut in the tube and then=0A welded around the cut= . Cuts could be staggered in rotation around=0A the tube as you move d= own the tube. Would likely need to 'break'=0A the straight edge of the= half-disc to resist fatigue. Small hole=0A at the edge of the cut wou= ld allow the 'break' to slide into the=0A gap.
=0A
=0A = I would have expected at least some power loss on a 13B because of=0A = the detuning effect of a mis-timed reflected shock wave; good to=0A = hear that it didn't. With a Renesis and no intake/exhaust overlap,=0A = it shouldn't make much if any difference to power as long as back=0A p= ressure is managed with a large pipe.
=0A
=0A Charlie
= =0A
=0A On 11/24/2019 11:48 AM, eanderson@carolina.rr.co= m wrote:
=0A
=0A
=0A = =0A =0A
Sorry, Neil,
=0A

=0A <= /div>=0A
Been a while, it was two exhaust pipes, one for each exh= aust=0A port.  Mistyped, error on the drawing the disc were 2 1= /2" dia=0A inside a 2 1/2" dia pipe.  The discs fit snugg enoug= h that when=0A one broke loose and spun on the rod,  it scored = the inside of=0A the exhaust tube.  I got the discs from McMast= er Carr.  Try=0A oversize SS washers.   The tubes wer= e actually glass pack=0A mufflers which had 2" dia inlet/outlet.&nbs= p; I cut the front off and=0A then after inserting the discs use wid= e metal clamps to put the=0A tube back together (welding would of co= urse have been better).
=0A

=0A
=0A I do not believe that any of the dimensions are critical=0A except = the discs should fit touching the inside of the tube if=0A possible.=   I called them discs but they were actually oversize=0A SS was= hers with a hole in the center for the rod.  I ended up=0A with= 5 discs inside each tube.  I used the spacing for the=0A short= er 36" long tube.  The idea was to have a large portion of=0A t= he shock wave dissipated inside each segment of the tube while=0A ke= ep the gas flowing freely.  
=0A

=0A =0A
It was truly quite and like I mentioned I could get 6000 rp= m=0A with my 13B on take off.  Large diameter tube/discs would = likely=0A permit more/easier gas flow, but since I can not weld, jus= t=0A finally gave up and went on to other things.
=0A
=0A
=0A
Ed
=0A

=0A
= =0A
 
=0A

=0A
=0A
=0A
=0A

=0A
=0A

=0A =
=0A

=0A
=0A
------ Original Mess= age ------
=0A =0A
To: "Rotary motors in aircraft" &l= t;f= lyrotary@lancaironline.net>
=0A
Sent: 11/23/2019 10:3= 5:27 PM
=0A
Subject: [FlyRotary] Re: Mufflers
=0A =

=0A
=0A
=0A
=0A

Ed,

= =0A

          = ;        On rereading your post, am I co= rrect in=0A believing that you had one pipe per exhaust?  A= total of 2=0A pipes?  How many discs were in each pipe?&nb= sp; I may have=0A misunderstood, but you say you had a 2.5 inch = disc fitted=0A inside a 2 .125" exhaust pipe.  If correct m= easurement how=0A did you manage to force 2.5 " inside  2.1= 25" pipe?  perhaps=0A the other way around measurement wise= ? 
=0A

=0A

Thanks,  Neil.
=0A =

=0A
On 11/21/2019 3:08 AM= , eanderson@carolina.rr.com=0A = wrote:
=0A
=0A
= =0A =0A #x2916bdc645c44e0 #xabd1a837f1e74c7 #x7682330dc2d04c= b4a94ca5f3d1872653{=0A font-family:'Segoe UI';=0A font-size:12pt;=0A backgr= ound-color:#FFF;=0A color:#000;=0A margin-left:0px;=0A margin-right:8px;=0A= }=0A#x2916bdc645c44e0 #xabd1a837f1e74c7 #x7682330dc2d04cb4a94ca5f3d1872653{= =0A font-family:'Segoe UI';=0A font-size:12pt;=0A}=0A =0A
Given the= recent interest in mufflers, I thought I=0A would throw in = my experience with home made muffer.  I=0A could hit 60= 00 rpm on take off with my  13B with the=0A 2.18:1 Gear= ratio.  You could stand within a wing width=0A with th= e engine idling and bearly hear it.  At 6000 rpm=0A it = was about 1/2 as loud as an unmufflered lycoming.  =0A =

=0A
=0A
The basic id= ea was to break up the shock wave while=0A minimizing gas = flow impedeance.  I used 1/8" thick 2"1=0A /2 Dia sta= inless steel disc inside of a 2 1/8" dia=0A stainless stee= l tube.  The disc has slits cut from the=0A outer edg= e approx 1/2" toward the center in 8 regions=0A as shown i= n the diagram.  Then each "tab" was twised=0A 45 deg = from the plane of the disc.  If you looked at=0A the = disc front on it look almost as a solid disc with=0A just = a small slot area showing through.  The idea was=0A t= hat the shock wave would basically see a "solid or=0A most= ly solid" disc where as the gas could still flow=0A throug= h the slots around the tabs.  I had a threaded=0A rod= extending the length of the tube with jam nuts on=0A each= side to hold the disc in place.
=0A
The reason fo= r the rod and nuts was not being a=0A welder-  I used= jam nuts - welding it turns out would=0A have been much b= etter as the nuts eventually became=0A loose.  That w= as not good, when one of the disc came=0A lose it started = to spin and greatly  impeded the gas=0A flow.  &= nbsp;Although folks told me it sound cool - like a=0A turb= in winding up.
=0A

=0A
= =0A
In any case, I decided that not being a welder=0A = there was no way I could remedy the defects.  I think= =0A if there were some way to "spot weld" the outer part= =0A of the tabs to the tube and perhas to a rod in the=0A = center the muffler would have extend it useful time. = =0A I flew approx 12 hours 
=0A =0A
including one trip to Tracy Crook (first extende= d=0A flight with muffler) by the time I got there at least= =0A one disc had broken loose and was spinning.  Trac= y was=0A kind enough to use his welding skills to weld the= =0A discs to the rod on one of the mufflers (had two one= =0A for each exhaust), but within another 6 hours or so=0A= disc in the other muffler started to spin.  Also I= =0A found that the shock wave pounding eventual would=0A = break off a tab or two since they were not anchored=0A = and could flex.
=0A

=0A =
=0A
Just thought I would throw the idea out= there in=0A case it has any merit.
=0A =

=0A
=0A
Best Regards=0A

=0A
=0A =
Ed
=0A

=0A
=0A =

=0A
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=0A =

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=0A
=0A

=0A=
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=0A
= =0A
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=0A
= =0A
=0A
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=0A =
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=0A=0A=0A=
------=_NextPart_16223188.940358931015--