Received-SPF: none
 receiver=logan.com; client-ip=211.29.132.186; envelope-from=lendich@optusnet.com.au
Message-ID: <003201c50ef7$070caf70$f668ecdc@george>
From: "George Lendich" <lendich@optusnet.com.au>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
References: <list-721686@logan.com>
Subject: Re: [FlyRotary] Re: PSRU - hub/prop end
Date: Thu, 10 Feb 2005 08:30:58 +1000
MIME-Version: 1.0
Content-Type: text/plain;
	charset="iso-8859-1"
Content-Transfer-Encoding: 7bit

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
>