For what its worth: I put a synthetic "grease" in two years ago and things are
still frictionless. It is Permatex: "Super Lube" The label says: Long-lasting
Multi-Purpose Synthetic-Based Lubricant With Teflon" It probably doesn't have
any petroleum products in it. Kind of expensive as far as grease goes at 11$ US
for 14 oz but it looks like that might last for several hundred years.... I
also
have a small plastic tube into each bearing with a grease groove around the
inside of each bearing so that I can inject the stuff in the future.
Cheers from the indecicive Colonies.
Tom Friedland xs A 079 (Jabiru 3300)
Tony Renshaw wrote:
> Duncan, Tony, Ferg, and anyone I've missed,
> Thanks for your replies regarding Front Bearing setups. I wonder Duncan if
> the expansion you got to the tufnol would have occurred with a graphite
> lubricant? Someone recently mentioned this option but my search engine for
> my 50 Megs of catagorised data is inadaquate. (not much point in having the
> data then is there). I will use a spacer I think, albeit a very thin one,
> as I intend on drilling a small hole in the top of the tufnol bearings to
> allow the insertion of a tubular applicator to inject atomised grease with
> a medium that later evaporates leaving the grease in place. Is the general
> consensus that the friction comes from the tufnol swelling throughout its
> thickness which effects the rear face of the CS03 bush against it, or is it
> the shrinking nature of the hole in the bearing constricting on the CS03
> bush? I can't visualise where the Brasso was applied to later remove the
> inbuilt friction? Thanks anyway for the help sofar! I don't think somehow
> that it will be the last of my questions on this subject somehow. Did
> anyone make a jig that straddles the central section of the module for
> orientation of the CS05 aileron tubes from front to back of the module
> including the bearing setups? (I just realised it didn't take me long to
> ask another question :-)
> Reg
> Tony Renshaw
>
> > I used polythene sheet as a shim. It was of "medium" thickness; about
> >0.0025". On completion of the whole set-up the freedom of movement was
> >first-rate and with no axial play.
> >Until that is the bearing was oiled.
> >Oil/grease causes Tufnol to swell (by 0.6% during my subsequent
> >measurements). So my nice 0.0025" end-float closed up by 0.003"!
> >Its not so tight that it stick-slips, but it adds noticeably to overall
> >control friction.
> >Moral: use 0.005" polythene?
> >
> >Duncan McFadyean
> >
> >-----Original Message-----
> From: Tony Renshaw <renshaw@ozemail.com.au>
> >Date: Tuesday, November 14, 2000 10:37 AM
> >Subject: Front Bearing setup
> >
> >
> >>Gidday,
> >>I am about to join the front flight control components either side of the
> >>front tufnol bearing and would like to see if anyone can suggest a setup
> >>that will ensure ideal spacing. The parts are the control fork(CS02) at the
> >>base of the control stick, the tufnol bearing(CS04), and the bush that
> >>passes through the tufnol bearing(CS03). The manual has you placing the
> >>bush vertically through the tufnol bearing and into the CS02 fork whilst
> >>the Redux cures. I have found that the face of CS02 that mates with the
> >>tufnol is not completely smooth and creates a "notchy" feeling when rotated
> >>backwards and forwards. This uneveness has been pollished out by placing
> >>both 800 and then 1200 Grit wet and dry onto a sheet of coffee table glass
> >>and polished out. Worked really well much to my surprise. I fear that too
> >>little tightness may give a sloppy mating either side of the tufnol bearing
> >>and too much tightness may be effected by temperature creating binding. It
> >>has been suggested that I pack out between the inner face of the bush(CS03)
> >>that mates with the tufnol bearing(CS04) with an ultra thin spacer such as
> >>a thin plastic medium, but what thickness, if at all?
> >>Any help or tips on this part of the flight control setup would be greatly
> >>appreciated.
> >>Reg
> >>Tony Renshaw
> >>Builder No.236
> >>Reg
> >>Tony Renshaw
> >>Builder No.236
> >>
> >
> >
> Reg
> Tony Renshaw
> Builder No.236
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