X-Junk-Score: 0 [] X-Cloudmark-Score: 0 [] X-Cloudmark-Analysis: v=2.3 cv=PbaBeRpd c=1 sm=1 tr=0 a=IfA6Mah5wS23SOkYPI2qXA==:117 a=_RQrkK6FrEwA:10 a=Jy3P6oOGoLoA:10 a=pGLkceISAAAA:8 a=Ia-xEzejAAAA:8 a=7g1VtSJxAAAA:8 a=jLljAQx8vQdG9QTxYpYA:9 a=rKTUBtwfrpTv0Uw-:21 a=Gkh95iFBm9BG8gLH:21 a=QEXdDO2ut3YA:10 a=Qa1je4BO31QA:10 a=gvSQh4r-fQ0A:10 a=S0wkRrzPavQA:10 a=1UKEwNcRibt5fRIZ:21 a=H0clZpeyI_-6W0wW:21 a=USLxjHBOE0q7Xpod:21 a=_W_S_7VecoQA:10 a=Urk15JJjZg1Xo0ryW_k8:22 a=grOzbf7U_OpcSX4AJOnl:22 a=Z5ABNNGmrOfJ6cZ5bIyy:22 a=UDnyf2zBuKT2w-IlGP_r:22 From: "Ernest Christley echristley@att.net" Received: from sonic301-24.consmr.mail.gq1.yahoo.com ([98.137.64.150] verified) by logan.com (CommuniGate Pro SMTP 6.2.14) with ESMTPS id 558505 for flyrotary@lancaironline.net; Thu, 23 Jul 2020 10:11:52 -0400 Received-SPF: none receiver=logan.com; client-ip=98.137.64.150; envelope-from=echristley@att.net DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=att.net; s=s1024; t=1595513494; bh=8UA4fMxeS7XkAICLMZ+DP4hUbzkdf/xfTYWtJgopwJs=; h=Date:From:To:In-Reply-To:References:Subject:From:Subject; b=kifWbL3+acoSAzGdBUG5tBlJ4OZT4NyM5jkUU5H4d+InN4MjEnrgAD9lwtmK5W1DwSL4Q+B/68UjtctwrLtxgZGdbr7VfqYsmsfA/zZrUopfUrKFoQXfnMnsKvSpjlni8zkSke00t9aLz3pixJUfLDbfSWNMXGMktG7U3p99hss= X-YMail-OSG: cu7oIEkVM1kvHcBVO_13s.SPQErzpT3TySXUWqtOfCwiDeByoqkUG3QRv31Z9Wf m4JSXYnQgsFnrkXlX3upLKRdWJgp4tNYQoQtJRwGHC7aIMJ5xi2J_XGB65RbX_toQkIRJK9av4o6 D63NXtoVHrnkSSWW0LBqtuYzh3IhJ2mjaqdV4XENC4KpAHKoGH1PSaPA8Y0V8KmOSL4HDdKJmoug 25wtYDEI0wq4tWMvVD7HbJ5sEOWRq8bzT93WxK4sevFXmW2vOSX11tAcINJu8nXZTXOlkTNWU3JC IiQuqj.ej1hQLhecxaNSMeCXjaQFGKrgrxDYAt3NMEE9OLdTG9ahiO7Dp8VlWplgNqdsW1klxsR9 r5GJtAY4MmxPd3cTjyy0XEVUnm0.h9XDWzqMCo4UN7LimSJjuAQpVSe7rmmY_89KfgSvLjf2ZhQd Bqqt.ffZTU4g5KgipsMNGwFiHfYBpgqAYUcVY8NEjS.Qe.STJ_IMpCWNLauuRXMTDJ.GVSyJjKJa 2gH7DLaB5EUzPtS1f4iZ.3xyFDT3mn28R.sB0L1fGKXAdIa.2l._I2Nz07ov5VRw8RI39jzZigX6 g8_3L.C6eZ_dFR_ADjxo7.1QERH.i0kTMSANo7YK3nnMWOnTjWbpgQwtot86EsarCvjRaKBvjH2m nQbDsLYGhPPwVsYp9AEkKCKw8p4BJDHNsY6I0zHMrJau8T8hqww43Q7LMh82pwDS3JmQ5WW.lFi9 MbaRjS3rr25HByf4M6jPXoB3EwxOtWQOy_g75ynSx_d4.jwjz2bS.8B5pzO9SpYHBnOnJkmfBHKl 66R4.y_ueL.rIvx.71AFEpBLyT52Pmqvs.N8n0pXil1602mkQojWOnakHTDyA_ytf41rBslg3qef wLapsWKbwBNuAkuVdH6l4RXEYFEPnToq4rVT0ZJ19fLjvia8HGRyg__F.ZzdcEi0Omr_8WQrEctZ Kxa_jrVvhDszJt9oMwBjTy9TmvPKU9hlmRmyMpbrbGpRLVrpWePWFHmc6CAIAZk1va0soq06bMux tefldxww_ZBvIudFx4WF5M85DQ10HQ9nOeAkIaBP7QFdEZSUOOha9gD.YhbFd6Hvh2w_xA2tXsav OttOaP5CUBaz6JDxaAep6Qxr1KXa.KMo1vBDe66PDL0bBwXPltYRLN57Cnm3Ryylzd9cyLek9hOU 3RdL71bGBWbiZHYShtLnT99Au9X5F8kUTzqMYi6Z6tUWeJppPx4AZjSJXNpn8oMtCTHKYa27BG49 jQkvkHj6feoe6l5_gc28kiRLwbP2FOqQAYmcmX_juTK2rRJMK4SX_jyyHc0scu4LSxUJnqv2P Received: from sonic.gate.mail.ne1.yahoo.com by sonic301.consmr.mail.gq1.yahoo.com with HTTP; Thu, 23 Jul 2020 14:11:34 +0000 Date: Thu, 23 Jul 2020 14:11:34 +0000 (UTC) To: "Charlie England ceengland7@gmail.com" Message-ID: <60386965.5095954.1595513494331@mail.yahoo.com> In-Reply-To: References: Subject: Re: [FlyRotary] Re: Engine Mount specs MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_Part_5095953_99550244.1595513494328" X-Mailer: WebService/1.1.16271 YMailNorrin Mozilla/5.0 (Macintosh; Intel Mac OS X 10.13; rv:77.0) Gecko/20100101 Firefox/77.0 Content-Length: 9708 ------=_Part_5095953_99550244.1595513494328 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable I was reading just last night in Sport Aviation that as a member of the EA= A, you can get a copy of Solidworks that will do stress analysis.=C2=A0 Has= anyone done this with a motor mount? On Thursday, July 23, 2020, 9:32:33 AM EDT, Charlie England ceengland7@= gmail.com wrote: =20 =20 =20 On Wed, Jul 22, 2020 at 11:23 PM Le Roux Breytenbach breytenbachleroux@gmai= l.com wrote: Hi All members: The 4130 chromemoly seamless pipe for the engine mount. What is the appropriate size for building a engine frame, as the included d= rawing of Paul L. ( copyright P.L ) The outside diameter and wall thickness ? =C2=A07/8=C2=A0 Inch OD x 0,069 =E2=80=9C Wall thickness ? or 0.120 W=20 1 inch x OD ?=20 Cant find any specifications for such a design. Sent from my iPhone Le Roux Breytenbach -- Homepage:=C2=A0 http://www.flyrotary.com/ Archive and UnSub:=C2=A0 =C2=A0http://mail.lancaironline.net:81/lists/flyro= tary/List.html For perspective, the RVs with up to an IO360 use 3/4" x 0.049" tubing. But = as Bobby & Andrew pointed out, crippling is the most critical issue, and al= l of the RV's tubes that are loaded in compression are much shorter than th= e bottom-most tube in that pic. I'd be most concerned about that tube; the = pair that are arrowed wouldn't concern me that much. Those aren't the only issues; you need to look at the load paths within wel= ded joints, also. The strongest welds are the ones that are stressed along = their length. A tension load perpendicular to a weld line is kinda 'worst c= ase'. You obviously want to avoid loading tubes in bending, but there are s= ituations where it *might* be acceptable, or even better. Ex: there are som= e 'bed mounts' (what that drawing effectively shows) for some Continental 6= cyl engines that use a much=C2=A0larger horizontal member (left arrow in th= e pic), and attach the compression member (bottom most tube in the pic) nea= r the mid point of the horizontal member. This loads the horizontal in bend= ing (requiring upsizing), but shortens the bottom compression member a lot,= reducing crippling loads on it. 'Everything is a compromise.' ;-) Be sure = that your airframe's 'stock' motor mount doesn't include a horizontal membe= r between the two upper firewall attach points. RVs don't need the tube, bu= t some composite or wood designs might not have the compression strength ac= ross the top of the fuselage that's needed=C2=A0 to resist those two points= trying to come together under positive G loading. Something I *wish* I could have=C2=A0done with my mount is to incorporate a= feature found on some radial engine mounts. They often have the 4 firewall= attach points being a U shaped bracket bolted through the bottom of the U,= to the firewall, and the motor mount termination a vertical tube at each c= orner. By pulling the bolts on the top & bottom of one side, the entire mou= nt & engine can be swung to one side to service stuff on thefirewall or the= back side of the engine. Trickier to do with a mount like a taildragger RV= , which has the gear leg sockets incorporated in the mount. =C2=A0I was fortunate enough to have two different engineers, both with str= uctural experience, critiquing my design attempts, and one of them is also = an excellent=C2=A0welder.... :-)=C2=A0 If you can find an engineer or struc= tures guy to look over your shoulder, it would be a good thing. Charlie =20 ------=_Part_5095953_99550244.1595513494328 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
I was reading just last nigh= t in Sport Aviation that as a member of the EAA, you can get a copy of Soli= dworks that will do stress analysis.  Has anyone done this with a moto= r mount?


=20
=20
On Thursday, July 23, 2020, 9:32:33 AM EDT, Charlie Eng= land ceengland7@gmail.com <flyrotary@lancaironline.net> wrote:


=

On Wed, Jul 22, 2020 at 11:23 PM Le Rou= x Breytenbach breyten= bachleroux@gmail.com <flyrotary@lancaironline.net> wrote:

Hi All members:
The 4130 chromemoly seamless pipe for the engine mount.
What is the appropriate size for building a engine frame, as the included d= rawing of Paul L. ( copyright P.L )
The outside diameter and wall thickness ?
 7/8  Inch OD x 0,069 =E2=80=9C Wall thickness ?
or 0.120 W

1 inch x OD ?
Cant find any specifications for such a design.



Sent from my iPhone
Le Roux Breytenbach --
Homepage:  http://www.flyrotary.com/
Archive and UnSub:   http://mail.lancaironline.= net:81/lists/flyrotary/List.html

For perspective,= the RVs with up to an IO360 use 3/4" x 0.049" tubing. But as Bobby & A= ndrew pointed out, crippling is the most critical issue, and all of the RV'= s tubes that are loaded in compression are much shorter than the bottom-mos= t tube in that pic. I'd be most concerned about that tube; the pair that ar= e arrowed wouldn't concern me that much.

Those aren't the only issues; y= ou need to look at the load paths within welded joints, also. The strongest= welds are the ones that are stressed along their length. A tension load pe= rpendicular to a weld line is kinda 'worst case'. You obviously want to avo= id loading tubes in bending, but there are situations where it *might* be a= cceptable, or even better. Ex: there are some 'bed mounts' (what that drawi= ng effectively shows) for some Continental 6cyl engines that use a much&nbs= p;larger horizontal member (left arrow in the pic), and attach the compress= ion member (bottom most tube in the pic) near the mid point of the horizont= al member. This loads the horizontal in bending (requiring upsizing), but s= hortens the bottom compression member a lot, reducing crippling loads on it= . 'Everything is a compromise.' ;-) Be sure that your airframe's 'stock' mo= tor mount doesn't include a horizontal member between the two upper firewal= l attach points. RVs don't need the tube, but some composite or wood design= s might not have the compression strength across the top of the fuselage th= at's needed  to resist those two points trying to come together under = positive G loading.

Something I *wish* I could have done with my mo= unt is to incorporate a feature found on some radial engine mounts. They of= ten have the 4 firewall attach points being a U shaped bracket bolted throu= gh the bottom of the U, to the firewall, and the motor mount termination a = vertical tube at each corner. By pulling the bolts on the top & bottom = of one side, the entire mount & engine can be swung to one side to serv= ice stuff on the firewall or the back side of the engine. Trickier to do with a mount like a= taildragger RV, which has the gear leg sockets incorporated in the mount.<= /div>
<= br>
 I was fortunate enough to have two different engineers, both with = structural experience, critiquing my design attempts, and one of them is al= so an excellent welder.... :-)  If you can find an engineer or st= ructures guy to look over your shoulder, it would be a good thing.

Charl= ie
------=_Part_5095953_99550244.1595513494328--