X-Junk-Score: 0 [] X-Cloudmark-Score: 0 [] X-Cloudmark-Analysis: v=2.3 cv=PbaBeRpd c=1 sm=1 tr=0 a=9JKJlijexIvT1S7cpBUTgA==:117 a=Q/ga6ogm2rCWgcvzDGMIiA==:17 a=x7bEGLp0ZPQA:10 a=DDNF8ybvv5wA:10 a=_RQrkK6FrEwA:10 a=HZJGGiqLAAAA:8 a=Ia-xEzejAAAA:8 a=pGLkceISAAAA:8 a=7g1VtSJxAAAA:8 a=8B3dlCde_aqJHvBZHAYA:9 a=aTdb8c3tE7JuiD4W:21 a=S0VbvDSGCWKwrm4y:21 a=QEXdDO2ut3YA:10 a=Qa1je4BO31QA:10 a=gvSQh4r-fQ0A:10 a=S0wkRrzPavQA:10 a=yBI_-jD6U6cEqkxD:21 a=2g56Q_Eo_ExM2W-U:21 a=qRqir95L8vJNr9BV:21 a=_W_S_7VecoQA:10 a=Urk15JJjZg1Xo0ryW_k8:22 a=grOzbf7U_OpcSX4AJOnl:22 From: "Le Roux Breytenbach breytenbachleroux@gmail.com" Received: from mail-ej1-f47.google.com ([209.85.218.47] verified) by logan.com (CommuniGate Pro SMTP 6.2.14) with ESMTPS id 559485 for flyrotary@lancaironline.net; Thu, 23 Jul 2020 13:46:21 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.218.47; envelope-from=breytenbachleroux@gmail.com Received: by mail-ej1-f47.google.com with SMTP id f12so7271457eja.9 for ; Thu, 23 Jul 2020 10:46:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=content-transfer-encoding:from:mime-version:subject:date:message-id :references:in-reply-to:to; bh=dxBAg/QaB4NIx09ArGnAiAjuLkPwJOMUrpS3DKiB4I4=; b=sNlQC/S1yIzu4eKkeRshMkuRxk6rrGtX+olymLlu9Xu/wC/8Wpf/tiui6CFgmn7Q5k b9NP44fKWcJ9hTW0co36fe4RKUzWRWlbC/DNn7o8nFsHC28LHgGWjsB4I+g3zDseJL3H Vgb2ulnhzJ6KFAZNznvGA1T9tSSJnV7J/xyzabAF4QilMZP4ejNWAYJ3vtSzsgEPrHnx VkcYs/1x0f6dWp/sfvEj6TZlsdIYbkcLC1r7+rpEBH3iSvSM31on+VYozt1wa1DIH/7w lWvcrnKlYmszIYHasI7IdE5yjbihrpTVInh8OMAcQQNGVx/5F7yqX9J15XoRUk9zXX3/ GCAw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:content-transfer-encoding:from:mime-version :subject:date:message-id:references:in-reply-to:to; bh=dxBAg/QaB4NIx09ArGnAiAjuLkPwJOMUrpS3DKiB4I4=; b=Q8YFcwwzJ/4r8te9vDgL3XTXV3NS9yJbY8NJWMF5wxYKl+h8HwONmz7w1wXXa5sV6l EZb9XlJN8Gk0SEKWUYV+RaW53LFWqc0PqeM0SZRQcCVLsSeV/m2An6iD2C6/ZVp12I4r czKf1sAcrEEuHldNxVsiI/ALrSJXHfc7YksrlL5GOs/EJ+ppakmYO+oVrgNxD4vo1pcC DGyTQYtYPa4mtaoRLwTWmdCiDzPwE+7Y4HV1pFpbGWdwYxsiNjkiXUKfcgGCX8gZVqg5 6xC1TQYulJT1866pcbFon7SqLnXI1QbY6dVpZOKFcaWwatiUghQ5jaZVkfTrlz9iIyUo ntJw== X-Gm-Message-State: AOAM533zE49KkKrrU/dv3ViGlcY1kfgjjxILlKNznYVPOBrGCYI2tyg/ NjqIPgxWJtucK+E2EdxVKR0yQwy6jfM= X-Google-Smtp-Source: ABdhPJyXUtvsgSpL78goNw23UzkvNpvmn9Y2zDTesm4C5msJylkncEenxspG97iO7QTEV+43yo1Elg== X-Received: by 2002:a17:906:8688:: with SMTP id g8mr5327438ejx.505.1595526363402; Thu, 23 Jul 2020 10:46:03 -0700 (PDT) Return-Path: Received: from [192.168.1.122] ([160.226.128.22]) by smtp.gmail.com with ESMTPSA id f10sm2432082ejx.95.2020.07.23.10.46.01 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Thu, 23 Jul 2020 10:46:02 -0700 (PDT) Content-Type: multipart/alternative; boundary=Apple-Mail-B03EAEBE-FF9B-416F-B4EE-F0DAF9A3A6B3 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (1.0) Subject: Engine Mount specs Date: Thu, 23 Jul 2020 19:45:59 +0200 Message-Id: References: In-Reply-To: To: Rotary motors in aircraft X-Mailer: iPhone Mail (17F80) --Apple-Mail-B03EAEBE-FF9B-416F-B4EE-F0DAF9A3A6B3 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Yes: Thanks to all of you responding on the mail, and contributing to my que= stions. The mounting that has to be build is , is for a tri-gear setup and apologies= for not mentioned it. Just want to know more or less the OD for the majority of the design but und= erstood that this is more complex and design is more critical for my Vision (= composite) fuselage. We will design a mount based on the info received from all of you. Luckily i took over 3 years ago a unfinished project of a Rans airframe and c= ut it into pieces. Believe i have almost enough material for the majority of the mount.Sorting o= ut the wall thickness of the same OD=E2=80=99s sizes.There is quite a differ= ence in weight, between the different wall thickness of the same OD=E2=80=99= s but =E2=80=9Coverkill=E2=80=9D is better than marginal. Will come back to you on the design on the group. Thanks again and happy building for all of you. Sent from my iPhone Le Roux Breytenbach=20 > On 23 Jul 2020, at 16:12, Ernest Christley echristley@att.net wrote: >=20 > =EF=BB=BF > 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. Has anyon= e done this with a motor mount? >=20 >=20 > On Thursday, July 23, 2020, 9:32:33 AM EDT, Charlie England ceengland7@gma= il.com wrote: >=20 >=20 >=20 >=20 > On Wed, Jul 22, 2020 at 11:23 PM Le Roux Breytenbach breytenbachleroux@gma= il.com wrote: >=20 > 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=20 >=20 > 1 inch x OD ?=20 > Cant find any specifications for such a design. >=20 >=20 >=20 > Sent from my iPhone > Le Roux Breytenbach -- > Homepage: http://www.flyrotary.com/ > Archive and UnSub: http://mail.lancaironline.net:81/lists/flyrotary/List= .html >=20 > 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 the= bottom-most tube in that pic. I'd be most concerned about that tube; the pa= ir that are arrowed wouldn't concern me that much. >=20 > Those aren't the only issues; you need to look at the load paths within we= lded joints, also. The strongest welds are the ones that are stressed along t= heir length. A tension load perpendicular to a weld line is kinda 'worst cas= e'. You obviously want to avoid loading tubes in bending, but there are situ= ations where it *might* be acceptable, or even better. Ex: there are some 'b= ed mounts' (what that drawing effectively shows) for some Continental 6cyl e= ngines that use a much larger horizontal member (left arrow in the pic), and= attach the compression member (bottom most tube in the pic) near the mid po= int of the horizontal member. This loads the horizontal in bending (requirin= g upsizing), but shortens the bottom compression member a lot, reducing crip= pling loads on it. 'Everything is a compromise.' ;-) Be sure that your airfr= ame's 'stock' motor mount doesn't include a horizontal member between the tw= o upper firewall attach points. RVs don't need the tube, but some composite o= r wood designs might not have the compression strength across the top of the= fuselage that's needed to resist those two points trying to come together u= nder positive G loading. >=20 > Something I *wish* I could have done with my mount is to incorporate a fea= ture found on some radial engine mounts. They often have the 4 firewall atta= ch points being a U shaped bracket bolted through the bottom of the U, to th= e firewall, and the motor mount termination a vertical tube at each corner. B= y pulling the bolts on the top & bottom of one side, the entire mount & engi= ne can be swung to one side to service stuff on the firewall or the back sid= e of the engine. Trickier to do with a mount like a taildragger RV, which ha= s the gear leg sockets incorporated in the mount. >=20 > I was fortunate enough to have two different engineers, both with structu= ral experience, critiquing my design attempts, and one of them is also an ex= cellent welder.... :-) If you can find an engineer or structures guy to loo= k over your shoulder, it would be a good thing. >=20 > Charlie --Apple-Mail-B03EAEBE-FF9B-416F-B4EE-F0DAF9A3A6B3 Content-Type: text/html; charset=utf-8 Content-Transfer-Encoding: quoted-printable Yes: Thanks to all of you responding on the= mail, and contributing to my questions.
The mounting that has to be bui= ld is , is for a tri-gear setup and apologies for not mentioned it.
Just want to know more or less the OD for the majority of the design but u= nderstood that this is more complex and design is more critical for my Visio= n (composite) fuselage.
We will design a mount based on the info r= eceived from all of you.
Luckily i took over 3 years ago a unfinis= hed project of a Rans airframe and cut it into pieces.
Believe i h= ave almost enough material for the majority of the mount.Sorting out the wal= l thickness of the same OD=E2=80=99s sizes.There is quite a difference in we= ight, between the different wall thickness of the same OD=E2=80=99s but =E2=80= =9Coverkill=E2=80=9D is better than marginal.
Will come back to yo= u on the design on the group.
Thanks again and happy building for a= ll of you.

Sent from my iPhoneLe Roux Breytenbach 

On 23 Jul 2020, at 16:12, Ernest Christley echristley@att.net <fly= rotary@lancaironline.net> wrote:

=EF=BB=BF
I was reading just last night= in Sport Aviation that as a member of the EAA, you can get a copy of Solidw= orks that will do stress analysis.  Has anyone done this with a motor m= ount?


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



On Wed, Jul 22, 2020 at 11:23 PM Le Roux Br= eytenbach breytenbachle= roux@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 dr= awing 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.lan= caironline.net:81/lists/flyrotary/List.html

<= div class=3D"yiv7285008332gmail_default" style=3D"font-size:small;">For pers= pective, the RVs with up to an IO360 use 3/4" x 0.049" tubing. But as Bobby &= amp; Andrew pointed out, crippling is the most critical issue, and all of th= e RV's tubes that are loaded in compression are much shorter than the 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; y= ou need to look at the load paths within welded joints, also. The strongest w= elds are the ones that are stressed along their length. A tension load perpe= ndicular to a weld line is kinda 'worst case'. You obviously want to avoid l= oading tubes in bending, but there are situations where it *might* be accept= able, or even better. Ex: there are some 'bed mounts' (what that drawing eff= ectively shows) for some Continental 6cyl engines that use a much large= r horizontal member (left arrow in the pic), and attach the compression memb= er (bottom most tube in the pic) near the mid point of the horizontal member= . This loads the horizontal in bending (requiring upsizing), but shortens th= e bottom compression member a lot, reducing crippling loads on it. 'Everythi= ng is a compromise.' ;-) Be sure that your airframe's 'stock' motor mount do= esn't include a horizontal member between the two upper firewall attach poin= ts. RVs don't need the tube, but some composite or wood designs might not ha= ve the compression strength across the top of the fuselage that's needed&nbs= p; to resist those two points trying to come together under positive G loadi= ng.

Something I *wish* I could have done with my mount is to incorpora= te a feature found on some radial engine mounts. They often have the 4 firew= all 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 m= ount & engine can be swung to one side to service stuff on the firewall or the back side of the engine. Trickier to do with a mount like a t= aildragger RV, which has the gear leg sockets incorporated in the mount.

<= /div>
&n= bsp;I was fortunate enough to have two different engineers, both with struct= ural experience, critiquing my design attempts, and one of them is also an e= xcellent welder.... :-)  If you can find an engineer or structures= guy to look over your shoulder, it would be a good thing.

Charlie
= --Apple-Mail-B03EAEBE-FF9B-416F-B4EE-F0DAF9A3A6B3--