X-Junk-Score: 0 [] X-KAS-Score: 0 [] From: "Andrew Martin andrew@martinag.com.au" Received: from mail-ej1-f46.google.com ([209.85.218.46] verified) by logan.com (CommuniGate Pro SMTP 6.4.0) with ESMTPS id 2567710 for flyrotary@lancaironline.net; Thu, 02 Nov 2023 19:40:49 -0400 Received-SPF: none receiver=logan.com; client-ip=209.85.218.46; envelope-from=andrew@martinag.com.au Received: by mail-ej1-f46.google.com with SMTP id a640c23a62f3a-9a6190af24aso228651166b.0 for ; Thu, 02 Nov 2023 16:40:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=martinag-com-au.20230601.gappssmtp.com; s=20230601; t=1698968431; x=1699573231; darn=lancaironline.net; h=to:subject:message-id:date:from:in-reply-to:references:mime-version :from:to:cc:subject:date:message-id:reply-to; bh=huer+mrR36HOw1tNpLUxHQiEm+5KbBk4+78KqAqKML0=; b=Xb0dyMEsk6x60Dh8socZQRz30UxT/CJNfgHqnypF4R7LFkuZG/yqp2MIdzsviMPgEg ZUjaT0ewfw27Nw6gU82pNM9yDwwAB8s/ph/Q40nQUtGsDY38Y1TcehpFIBdvDhBfGvKF 1A86n99PrTEDSSHACqGOBGLOqdTJ+qz5QZ7vsNoUrIpAbcc8CwEUOPIVat/2zrDf2QaE 904EG2P/pEbf+tVNwuaDZIuRNUgC4hPreFBb/KhnpDnZ5f5PNlihDUhB03wnMBBQY1sN E5cN5/jl6msn15Qeag7GPv/EIeyJsqAWE9PuwfbmHw/6PpSnj/dVhzOrnCtRf253elCk 4BoA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1698968431; x=1699573231; h=to:subject:message-id:date:from:in-reply-to:references:mime-version :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=huer+mrR36HOw1tNpLUxHQiEm+5KbBk4+78KqAqKML0=; b=CfiA2dGUJFgLyWc0/mB1eoOIG3KQtSQNizVe5zLbb2u9YMjT0178G996rJEQCBOJ3P kfBusmuKefoaz6Ekr06j+Q511ka+537jurePD1gGu1woA56AVcbrie+KQqPJUBB2mdt0 UsMZsAAdOtGiUM4ZfAqtubQXPatpx5KWx6QcfSstpJNSeIBPmRw8N2rOwAh5T8cm6Gfj 6BmMWPSRz3HkAzS+1FKIbwKw2YGbhpwG1hJVBVE1jfhP3r7wSExp6Ns/TmWN4Rtcfsn0 rn2fh5agqMU855MLnd/6dTXDkQSYO9fPRtm2IEW+bOS45XIAoMzHPfZzSkS5M2uHuTnk 1z7A== X-Gm-Message-State: AOJu0YwVhpfDvPMQ9CRTOXBNiO2iQu/CmxCA0E3N/bWGxIZI/1H5Segw XwiJQQTjkQC7DMDPBxzUGvvfyUPT0PvcPU/dfiuD6x7dzCTLDYY= X-Google-Smtp-Source: AGHT+IH75fzCxOGRmtP9Kqz1QFiNdD9qCTUolJMyt4ygVZ4ES24Ba0nG6tjHgqFr1hxGGklVdvfnIXKw/R9UE09O2Yk= X-Received: by 2002:a17:906:11c8:b0:9a5:d657:47e1 with SMTP id o8-20020a17090611c800b009a5d65747e1mr4109207eja.43.1698968430975; Thu, 02 Nov 2023 16:40:30 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: Date: Fri, 3 Nov 2023 07:40:18 +0800 Message-ID: Subject: Re: [FlyRotary] Re: Updates on Muffler Experiences? To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary="000000000000d02df3060933e975" --000000000000d02df3060933e975 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Doug, I really cannot remember, was made from bits of scrap from the farm workshop, Will see if I got more to measure. Thing is, you can use cast iron if you want cheap but will be heavy, Inconel is good if you want lightest, but you better be a good welder. You make the choice. My first setup was made from 3mm mild steel (again scrap bits of cattleyard rails) worked fine for a bit but design was loud and became obvious in that it was not going to last longterm. Best to just make something to get flying. Not really much effort in upgrading to better materials later, failures tend to happen over time so If you inspect after each flight any cracks/deformation that appear will be obvious long before failure, main thing is to expand the exhaust gas as soon as possible as that drops temps fastest and get it out of the cowl with the least amount of pipework. There are tricks to quiet down a loud system that can be retrofitted later if need be ( similar idea as a rifle silencer) to quieten. Andrew On Thu, 2 Nov 2023 at 9:11 pm, Doug Lomheim rv9flyer13b@gmail.com < flyrotary@lancaironline.net> wrote: > Andrew: > > Thanks for the great information! Are you using 304 or 321 stainless > steel, and by =E2=80=9Cthick wall=E2=80=9D, is that about .065 or so? > > Doug > > -- Regards Andrew Martin Martin Ag --000000000000d02df3060933e975 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Doug, I really cannot remember, was made from bits of scr= ap from the farm workshop, Will see if I got more to measure.
Thing is, you can use cast iron if you want cheap but will be hea= vy, Inconel is good if you want lightest, but you better be a good welder. = You make the choice.=C2=A0
My first setup was made f= rom 3mm mild steel (again scrap bits of cattleyard rails) worked fine for a= bit but design was loud and became obvious in that it was not going to las= t longterm.
Best to just make something to get flyin= g. Not really much effort in upgrading to better materials later, failures = tend to happen over time so If you inspect after each flight any cracks/def= ormation that appear will be obvious long before failure, main thing is to = expand the exhaust gas as soon as possible as that drops temps fastest and = get it out of the cowl with the least amount of pipework. There are tricks = to quiet down a loud system that can be retrofitted later if need be ( simi= lar idea as a rifle silencer) to quieten.
Andrew

On Thu, 2 Nov 2023 at 9:11 pm, Doug Lomheim rv9flyer13b@gmail.com <flyrotary@lancaironline.net> wrote:
Andrew: = =C2=A0

Thanks for the g= reat information!=C2=A0 Are you using 304 or 321 stainless steel, and by = =E2=80=9Cthick wall=E2=80=9D, is that about .065 or so? =C2=A0

Doug=C2=A0

--
Regards Andrew Martin Martin Ag
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