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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