Return-Path: Received: from [65.54.168.112] (HELO hotmail.com) by logan.com (CommuniGate Pro SMTP 4.3c1) with ESMTP id 724022 for flyrotary@lancaironline.net; Thu, 10 Feb 2005 13:53:46 -0500 Received-SPF: pass receiver=logan.com; client-ip=65.54.168.112; envelope-from=lors01@msn.com Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC; Thu, 10 Feb 2005 10:53:00 -0800 Message-ID: Received: from 4.174.7.95 by BAY3-DAV8.phx.gbl with DAV; Thu, 10 Feb 2005 18:52:47 +0000 X-Originating-IP: [4.174.7.95] X-Originating-Email: [lors01@msn.com] X-Sender: lors01@msn.com From: "Tracy Crook" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: PSRU - hub/prop end Date: Thu, 10 Feb 2005 13:52:45 -0500 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_00CC_01C50F77.CC388C30" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: MSN 9 X-MIMEOLE: Produced By MSN MimeOLE V9.10.0009.2900 Seal-Send-Time: Thu, 10 Feb 2005 13:52:45 -0500 X-OriginalArrivalTime: 10 Feb 2005 18:53:00.0752 (UTC) FILETIME=[BE580D00:01C50FA1] This is a multi-part message in MIME format. ------=_NextPart_000_00CC_01C50F77.CC388C30 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable One question, did you plug in the RPM used in this application when = calculating bearing life? It goes down real fast on some bearings = (especially tapered rollers). Tracy ----- Original Message -----=20 From: George Lendich=20 To: Rotary motors in aircraft=20 Sent: Wednesday, February 09, 2005 5:30 PM Subject: [FlyRotary] Re: PSRU - hub/prop end Ernest, Seems like you have it completely under control, if you researched the = life of the bearings, under the loads they carry you will find that their projected life would be something like 250,000 hours. That's the answer I got from Timken! but the sizes may have been = different. Anyway it gives you a bit of an idea. George ( down under) > Did some research last night, and I am now very comfortable with the > taper bearing. There is in fact one on the other end, but I was not > considering it, because I view all the forces trying to pull the hub = off > the shaft and the rear bearing won't see much stress in that = situation. > Now I realize that the rear bearing will be important to keep the = hub > aligned properly, and this won't happen unless the correct preload = is > applied. I also understand that the correct term for the load = forces > are axial and radial, not longitudanal and lateral. > > >The nut will be for preload, remember when you put it back on, that = you know > >the preload number. > > > > > > > > Unfortunately, the nut was finger tight and the keyed lock washer = had > never been bent to lock it in place. I have no idea what the = preload > number is or how to determine it. On cars, we always just tightened = the > nut till there was no side play in the wheel but it still spun = freely. > I would think that I'd want it a little tighter in this application, > since the forces will be trying to open up the rear seal and the = only > thing stopping that will be the preload...but I don't have a number = to > attach to 'little tighter'. > > >Again go to a bearing supply company, I have no doubt that there = would be a > >standard seal to fit. Who ever made this PSRU would look for = standard seal > >sizes. > > > >George ( down under) > > > > > > Thank you, George. I looked over Tracey's website (thank you, = Tracey), > and several other places. I think in the application that this hub = was > meant for (a racecar wheel), that the car's wheel was the seal. I = have > a 1/4" plate that will sandwich nicely between the prop and the hub. = I > can easily machine a recess into it for a standard seal (I think). > > >> Homepage: http://www.flyrotary.com/ > >> Archive: = http://lancaironline.net/lists/flyrotary/List.html > >> Homepage: http://www.flyrotary.com/ >> Archive: = http://lancaironline.net/lists/flyrotary/List.html ------=_NextPart_000_00CC_01C50F77.CC388C30 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
One question,  did you plug in the RPM used in this = application when=20 calculating bearing life?  It goes down real fast on some bearings=20 (especially tapered rollers).
 
Tracy
----- Original Message -----
From: George Lendich
To: Rotary motors in = aircraft
Sent: Wednesday, February 09, = 2005 5:30=20 PM
Subject: [FlyRotary] Re: PSRU - = hub/prop=20 end

Ernest,
Seems like you have it completely under = control, if=20 you researched the life
of the bearings, under the loads they carry = you=20 will find that their
projected life would be something like 250,000 = hours.
That's the answer I got from Timken! but the sizes may have = been=20 different.
Anyway it gives you a bit of an idea.
George ( down=20 under)

> Did some research last night, and I am now very = comfortable=20 with the
> taper bearing.  There is in fact one on the = other end,=20 but I was not
> considering it, because I view all the forces = trying to=20 pull the hub off
> the shaft and the rear bearing won't see much = stress=20 in that situation.
> Now I realize that the rear bearing will be = important to keep the hub
> aligned properly, and this won't = happen=20 unless the correct preload is
> applied.  I also understand = that=20 the correct term for the load forces
> are axial and radial, not = longitudanal and lateral.
>
> >The nut will be for = preload,=20 remember when you put it back on, that you
know
> >the = preload=20 number.
> >
> >
> >
>
> = Unfortunately,=20 the nut was finger tight and the keyed lock washer had
> never = been bent=20 to lock it in place.  I have no idea what the preload
> = number is=20 or how to determine it.  On cars, we always just tightened = the
>=20 nut till there was no side play in the wheel but it still spun = freely.
>=20 I would think that I'd want it a little tighter in this = application,
>=20 since the forces will be trying to open up the rear seal and the = only
>=20 thing stopping that will be the preload...but I don't have a number = to
>=20 attach to 'little tighter'.
>
> >Again go to a bearing = supply=20 company, I have no doubt that there would be
a
> >standard = seal to=20 fit. Who ever made this PSRU would look for standard
seal
>=20 >sizes.
> >
> >George ( down under)
> = >
>=20 >
>
> Thank you, George.  I looked over Tracey's = website=20 (thank you, Tracey),
> and several other places.  I think = in the=20 application that this hub was
> meant for (a racecar wheel), = that the=20 car's wheel was the seal.  I have
> a 1/4" plate that will = sandwich=20 nicely between the prop and the hub.  I
> can easily = machine a=20 recess into it for a standard seal (I think).
>
> = >> =20 Homepage:  http://www.flyrotary.com/
> = >>  Archive:   http://lancai= ronline.net/lists/flyrotary/List.html
>



>>=  =20 Homepage:  http://www.flyrotary.com/
>&= gt; =20 Archive:   http://lancai= ronline.net/lists/flyrotary/List.html
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