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View Full Version : push rod and bearing inspection.


john firth
April 28th 18, 10:21 PM
Further to my post on corrosion in the wing, I have completed inspection of
everything I could see of the drive mechanism of my PIK 20E flaperon drives.

A fibre optic monochrome display was very hard to interpret; However
a 10w white LED ( at 2 w) on a 1/4 in Al tube allowed visual inspection
of the rod ends through the access holes. I was happy to find negligible
corrosion. The glider is tied down with covers most of the season.

Lubrication was via a 1/8 tube attached to a pressure oil can with SAE 40
motor oil, but a drip feed would work perfectly well.

Many sections of the mylar seals were coming loose due to the adhesive
being dried out; this is a pain. I wonder if there is a good alternative to
the double sided transfer tape.
Is contact cement any better after 3-4 years?

John F

April 30th 18, 09:23 AM
Before applying the double sided tape, the underlying surface should lightly be roughened (e.g. 240 grid paper) and thoroughly cleaned with a suitable solvent like Acetone. After application, the mylar tapes should be covered with white Tesa plastic tape. This prevents the leading edge from peeling off and gives some UV protection to the double sided transfer tape.

If applied properly, these tapes are good for 10 years and more. They properly do not last that long on surfaces stored outside.

April 30th 18, 08:43 PM
With UH's expert oversight and assistance, completed a wing refinish last month on my ASW 24. The original, 26-year-old mylar seals were still working fine (I always trailer with the aileron locks) and stuck down very tightly.. The biggest problem was getting the old adhesive off.

I had replaced the Tesa safety tape about 10 years ago and it was less impressive--the adhesive was more powdery when we pulled the tape off--but still intact.

My glider lives in the trailer, which is stored outside. I suspect the life of the seals would be reduced if the glider were tied down outside..

Now to see if the replacement seals last another 26 years! :)

Chip Bearden
JB

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