X-Junk-Score: 0 [] X-Cloudmark-Score: 0 [] X-Cloudmark-Analysis: v=2.3 cv=WeVylHpX c=1 sm=1 tr=0 a=0mq6FIRulfhJeCy69GKncQ==:117 a=hgd9Fbv9zUJYmKSJFKl7lQ==:17 a=jpOVt7BSZ2e4Z31A5e1TngXxSK0=:19 a=x7bEGLp0ZPQA:10 a=K7ySfSCCDxUA:10 a=pxVhFHJ0LMsA:10 a=pGLkceISAAAA:8 a=Ia-xEzejAAAA:8 a=oBdLjE-hAAAA:8 a=ayC55rCoAAAA:8 a=ioMCB4zLcUf07oJDHFQA:9 a=jBD9K0ap2QZ2kzVx:21 a=jTUsuFZRUx4Fy22m:21 a=QEXdDO2ut3YA:10 a=S0wkRrzPavQA:10 a=4PR2P7QzAAAA:8 a=UD4ENcH7gPhzQHvchFQA:9 a=nw7zZIOIFiyw9lXa:21 a=TKsiY7udCWVQ9I_D:21 a=hbbbpInsRQZ8ahvq:21 a=frz4AuCg-hUA:10 a=Urk15JJjZg1Xo0ryW_k8:22 a=5CSF7l4QdX2tYyTgikZJ:22 a=B_RyunTPg8udlmYm5Cu2:22 a=4dqwQCo7Po2mVW515mGf:22 From: "Matt Boiteau mattboiteau@gmail.com" Received: from mail-qk1-f179.google.com ([209.85.222.179] verified) by logan.com (CommuniGate Pro SMTP 6.2.14) with ESMTPS id 13321334 for flyrotary@lancaironline.net; Fri, 20 Dec 2019 11:19:15 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.85.222.179; envelope-from=mattboiteau@gmail.com Received: by mail-qk1-f179.google.com with SMTP id z14so6803445qkg.9 for ; Fri, 20 Dec 2019 08:19:15 -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=HLbRdnvGX9OFGgcZXTmPqqii7uU1VV4EjyagWLrcZcc=; b=R9HMbzey+nJd8DrmumISot9nAkrlkT/nrOLyPoMOuNq9mj0dcFrzDROf3uaVaXQ6PG plbL1wVfUkWN9ImQL8pOFo4t6FruQJE+kapdMml786eRpxm3Vlxz3QsgCpHWWie4Rmwa z3mRg1GpA6baCCmh73SOeCIahqKUrtHDIuSTFpnytEZorWAiCgGCfARYh0ZkND4jHV/C b6KfafWqWtZ38YZfMnG5k3UCYvLR+R7ByumLgJd3RoDmgGVIyy6atGiESjvWtPpHBq7J yWBIKihHAEVN/ceSFfQwVhdPkYfMDX7+DBRnc6+W7UPMWx/1y/LtUmPxFNVEDcyQWKFZ uP9A== 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=HLbRdnvGX9OFGgcZXTmPqqii7uU1VV4EjyagWLrcZcc=; b=X/zdItWF7+3ksCjsFtV+NA2LYqaU+ws8JZcx7tKIXTaDxAY9JZAWtJyKPSYbOQ8cpo KZmXZhMnal44XRzD9OlEvk/Jnm1C54ktq2BX4paZNrtdicDo3SAFam+Ui6Y64lESPNDW yfxV6Df151S4EvTQKF//h2NXigPLVAckHxn2dxjuSJtLx+j/xQKAftUx1uEdJsNBaitt Zli9ak6eMWvR7YAr3Q6ppdOk3qHhOiY6Yah7/LXCSUbthOnni2aaLVJVgqMoXLyrkjFE OeCsMadhJ/YQJ4KmCkkj6k8bSmywd29PUU/++Ppf55m2OEDT/5bR6D6TIQHiGEEoYkEf Vc6A== X-Gm-Message-State: APjAAAV99ORrSslM3AJrz+WBjxbL8WcfqIXOprNKwXz4cz4Kkyp92KN0 7jh/iN12idQtfwrMhs8xevaMWW2vot8= X-Google-Smtp-Source: APXvYqxuh1h/I+e/fvlHuvt/rnDdmlhBvxmAGxw87QxIvrko71pvnyC8u3SZiSMnXZDLNX4PH/nUCw== X-Received: by 2002:a37:a256:: with SMTP id l83mr14141014qke.252.1576858738141; Fri, 20 Dec 2019 08:18:58 -0800 (PST) Return-Path: Received: from [192.168.0.134] ([67.58.218.7]) by smtp.gmail.com with ESMTPSA id e19sm3277074qtc.75.2019.12.20.08.18.57 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 20 Dec 2019 08:18:57 -0800 (PST) Content-Type: multipart/alternative; boundary="----=_NextPart_15781450.557240000251" MIME-Version: 1.0 Date: Fri, 20 Dec 2019 11:18:56 -0500 Message-ID: <849e91c5-e395-404f-bdba-0aa8e30b7a1a@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: 849e91c5-e395-404f-bdba-0aa8e30b7a1a@getmailbird.com ------=_NextPart_15781450.557240000251 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable You have to be careful on the Burns site. When you click their dropdowns, o= ther dropdowns change automatically to match their stock/availability.=C2= =A0Biggest they have for 16ga is 2.5" @ $140.=C2=A0The largest size they ha= ve is 3.5" but it's only 20ga which I think is to thin for the main body of= muffler. What exhaust size do most people stick with, 2.5" or 3" for n/a ? On the ca= r forums, most are adamant to go to 3" for n/a Rx8, but have no actual data= as to why. Just thinking, bigger is better. I can see turbo being 3", but = I have a hard time believing 2.5" isn't good enough for n/a. - Matt Boiteau On 2019-12-19 11:12:42 PM, Charlie England ceengland7@gmail.com wrote: Try https://burnsstainless.com/ [https://burnsstainless.com/] A quick look found 3.5" @$21/ft. On 12/19/2019 9:23 PM, Matt Boiteau mattboiteau@gmail.com [mailto:mattboite= au@gmail.com] wrote: 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 [mailto:eanderson@caro= lina.rr.com] [mailto:flyrotary@lancaironline.= net] 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 ------=_NextPart_15781450.557240000251 Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable
=0A You have to = be careful on the Burns site. When you click their dropdowns, other dropdow= ns change automatically to match their stock/availability. Biggest the= y have for 16ga is 2.5" @ $140. The largest size they have is 3.5" but= it's only 20ga which I think is to thin for the main body of muffler.
<= br>What exhaust size do most people stick with, 2.5" or 3" for n/a ? On the= car forums, most are adamant to go to 3" for n/a Rx8, but have no actual d= ata as to why. Just thinking, bigger is better. I can see turbo being 3", b= ut I have a hard time believing 2.5" isn't good enough for n/a.
- Matt Boiteau
=0A =
=0A

On 2019-12-19 11:12:42 PM, Charl= ie England ceengland7@gmail.com <flyrotary@lancaironline.net> wrote:<= /p>

=0A
Try
=0A https://burnsstainless.com/
=0A
=0A A quick look fou= nd 3.5" @$21/ft.
=0A
=0A On 12/19/2019 9:23 PM, Matt Boite= au mattboiteau@gmail.com wrote:
=0A
=0A
= =0A =0A
Anyone have a good=0A source (U= SA side) for 321 tubing? Looking to rebuild a new=0A exhaust like&nb= sp;Gary Schwarz.=0A 4" or 5" in siz= e. I've only found one place SPD Exhaust, that=0A is $130 a foot f= or 4inch tube.=0A

=0A
=0A
- Matt Boiteau
=0A
= =0A

On 2019-11-26= =0A 10:37:22 AM, eanderson@carolina.rr.com=0A = <flyrotary@lancaironline.net> wrote:

=0A
=0A
Interes= ting idea about the diagonal placement of the=0A discs, Charli= e.  When a disc did break loose from the jam=0A nuts and = spung, it really restricted gas flow, so I think=0A welding th= e disc in place is likely the best solution.
=0A

= =0A
=0A
  I think your idea about dia= gonl slots would be worth=0A trying.  It may be that simp= ly cutting say 1/4 - 1/3 of=0A the disc off for gas flow and t= hen alternating the side of=0A the tube with the slot in it wo= uld still cause the shock=0A wave to see a solid wall  bo= unce back and forth between=0A disc (mostly) and still permit = good gas flow.  
=0A

=0A =0A
Apparently the reduction of the shock wave in the=0A = several sections did not result in the loss you mention=0A = due to refledted shock wave.  
=0A
=0A
=0A
You and Tupper have a great T= hanksgiving. 
=0A

=0A
=0A =
Ed
=0A

=0A
=0A =
------ Original Message ------
=0A = =0A
To: "Rotary motors in aircraft" <flyrotary@lancaironlin= e.net>
=0A
Sent: 11/24/2019 2:48:50 PM
=0A=
Subject: [FlyRotary] Re: Mufflers
=0A
=0A
=0A
=0A
=0A =
Ed, I really wish I'd had a=0A = chance to hear those mufflers; I've been fascinated by=0A = the idea since you first mentioned it many years ago.=0A = Do you remember what you were running before, and how=0A = much takeoff rpm you gained when you made the switch?
=0A =
=0A With only 5 washers, I wonder if the = same effect could=0A be achieved using half-discs slid int= o diagonal slots=0A cut in the tube and then welded around= the cut. Cuts=0A could be staggered in rotation around th= e tube as you=0A move down the tube. Would likely need to = 'break' the=0A straight edge of the half-disc to resist fa= tigue.=0A Small hole at the edge of the cut would allow th= e=0A 'break' to slide into the gap.
=0A =
=0A I would have expected at least some power loss o= n a=0A 13B because of the detuning effect of a mis-timed= =0A reflected shock wave; good to hear that it didn't.=0A = With a Renesis and no intake/exhaust overlap, it=0A = shouldn't make much if any difference to power as long=0A = as back pressure is managed with a large pipe.
=0A =
=0A Charlie
=0A
=0A = On 11/24/2019 11:48 AM, eanders= on@carolina.rr.com=0A wrote:
=0A =0A
=0A #x2916bdc645c44e0 blockquote.cite{=0A margin-left:5p= x;=0A margin-right:0px;=0A padding-left:10px;=0A padding-right:0px;=0A bord= er-left:1px solid #CCC ;=0A}=0A#x2916bdc645c44e0 blockquote.cite2{=0A margi= n-left:5px;=0A margin-right:0px;=0A padding-left:10px;=0A padding-right:0px= ;=0A border-left:1px solid #CCC;=0A margin-top:3px;=0A padding-top:0px;=0A}= =0A#x2916bdc645c44e0 a img{=0A border:0px;=0A}=0A#x2916bdc645c44e0 li#x2916= bdc645c44e0 [style=3D"'text-align: center;'"],#x2916bdc645c44e0 li#x2916bdc= 645c44e0 [style=3D"'text-align: right;'"]{=0A list-style-position:inside;= =0A}=0A#x2916bdc645c44e0{=0A font-family:Segoe UI;=0A font-size:12pt;=0A}=0A
Sorry, Neil,
=0A
=0A
=0A
Been a while, it = was two exhaust pipes, one for=0A each exhaust port.&nbs= p; Mistyped, error on the drawing=0A the disc were 2 1/2= " dia inside a 2 1/2" dia pipe. =0A The discs fit s= nugg enough that when one broke loose=0A and spun on the= rod,  it scored the inside of the=0A exhaust tube.=   I got the discs from McMaster Carr. =0A Try = oversize SS washers.   The tubes were actually=0A = glass pack mufflers which had 2" dia inlet/outlet. =0A = I cut the front off and then after inserting the=0A = discs use wide metal clamps to put the tube back=0A = together (welding would of course have been better).
=0A =

=0A
=0A
I do not = believe that any of the dimensions are=0A critical excep= t the discs should fit touching the=0A inside of the tub= e if possible.  I called them discs=0A but they wer= e actually oversize SS washers with a=0A hole in the cen= ter for the rod.  I ended up with 5=0A discs inside= each tube.  I used the spacing for the=0A shorter = 36" long tube.  The idea was to have a large=0A por= tion of the shock wave dissipated inside each=0A segment= of the tube while keep the gas flowing=0A freely. =  
=0A

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

=0A
=0A
&n= bsp;
=0A

=0A
=0A =

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

=0A =
=0A

=0A
=0A =
------ Original Message ------
=0A = =0A
To: "Rotary motors in = aircraft" <flyrotary@lancaironline.net>
=0A Sent: 11/23/2019 10:35:27 PM
=0A
Subject: [Fl= yRotary] Re: Mufflers
=0A

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

Ed,

=0A

    &nbs= p;             = On rereading your post, am I=0A correct in believing= that you had one pipe per=0A exhaust?  A total= of 2 pipes?  How many discs=0A were in each pi= pe?  I may have misunderstood,=0A but you say y= ou had a 2.5 inch disc fitted=0A inside a 2 .125" ex= haust pipe.  If correct=0A measurement how did = you manage to force 2.5 "=0A inside  2.125" pip= e?  perhaps the other way=0A around measurement= wise? 
=0A

=0A

T= hanks,  Neil.
=0A

=0A =
On 11/21/2019 3:08=0A = AM, eanderson@carolina.rr.com=0A = wrote:
=0A
=0A =
=0A =0A =0A =
=0A =
Given the recent interest in mufflers, I=0A = thought I would throw in my experience with=0A = home made muffer.  I could hit 6000 rpm on=0A = take off with my  13B with the 2.18:1 Gear=0A = ratio.  You could stand within a wing width=0A = with the engine idling and bearly hear it. =0A = At 6000 rpm it was about 1/2 as loud as an=0A = unmufflered lycoming.  =0A =

=0A
=0A =
The basic idea was to break up the=0A = shock wave while minimizing gas flow=0A imped= eance.  I used 1/8" thick 2"1 /2 Dia=0A s= tainless steel disc inside of a 2 1/8"=0A dia = stainless steel tube.  The disc has=0A sl= its cut from the outer edge approx 1/2"=0A tow= ard the center in 8 regions as shown in=0A the= diagram.  Then each "tab" was twised=0A = 45 deg from the plane of the disc.  If you=0A = looked at the disc front on it look almost=0A = as a solid disc with just a small slot=0A = area showing through.  The idea was that=0A = the shock wave would basically see a=0A "s= olid or mostly solid" disc where as the=0A gas= could still flow through the slots=0A around = the tabs.  I had a threaded rod=0A extend= ing the length of the tube with jam=0A nuts on= each side to hold the disc in=0A place.
= =0A
The reason for the rod and nuts was not= =0A being a welder-  I used jam nuts - we= lding=0A it turns out would have been much bet= ter=0A as the nuts eventually became loose.&nb= sp; That=0A was not good, when one of the disc= came=0A lose it started to spin and greatly&n= bsp;=0A impeded the gas flow.   Alth= ough folks=0A told me it sound cool - like a t= urbin=0A winding up.
=0A =

=0A
=0A =
In any case, I decided that not being a=0A = welder there was no way I could remedy the=0A = defects.  I think if there were some way=0A = to "spot weld" the outer part of the tabs=0A = to the tube and perhas to a rod in the=0A = center the muffler would have extend it=0A = useful time.  I flew approx 12 hours 
=0A =
=0A
including one tr= ip to Tracy Crook=0A (first extended flight wi= th muffler) by=0A the time I got there at leas= t one disc had=0A broken loose and was spinnin= g.  Tracy was=0A kind enough to use his w= elding skills to=0A weld the discs to the rod = on one of the=0A mufflers (had two one for eac= h exhaust),=0A but within another 6 hours or s= o disc in=0A the other muffler started to spin= .  Also I=0A found that the shock wave po= unding=0A eventual would break off a tab or tw= o=0A since they were not anchored and could=0A= flex.
=0A
=0A
=0A <= div>Just thought I would throw the idea out=0A = there in case it has any merit.
=0A
<= br>=0A
=0A Best Regards
=0A

=0A =
=0A
=0A =
=0A
=0A = =0A
=0A =0A= =0A =0A =0A = =0A =0A =0A = ------=_NextPart_15781450.557240000251--