The other way is to clean the drive sleeve and torque tube surfaces with
acetone and a jet of compressed air, then use a wicking grade Loctite to
bond them together after lining up the tailplane trailing edges. It must be
about 800 to 900 hours since I did that to mine and they are still solid. I
will, of course, have to deal with dismantling if I ever have to, but a heat
source inside the torque tube should do the trick. I also had to provide
some lubricating tubes to replace the oil into the torque tube bearings,
because the acetone washes that out too.
Regards,
William
----- Original Message -----
From: <rparigor@suffolk.lib.ny.us>
Sent: Sunday, August 27, 2006 5:14 AM
Subject: Re: Europa-List: Mod. 62 - Replacement of tailplane torque tube
drive pins
>
> Hello Gert
>
> "I am interested in comments from folks who have done this mod. the Europa
> way to hear from their experience."
>
> YIKES
>
> My kit A-265 came through with 3/8 pins. The holes were trilobal, 2 of the
> pins dropped in by hand, the other 2 way too loose.
>
> Andy sent me 3/8" pins .001" oversized. Not even close to resolve.
>
> Next he sent me 10mm reamer and 4 10mm pins. Better but it is a new build
> and there was play 1/2 way towards unacceptable. The reamer cut a little
> oversized and the pin sizes were not too precise.
>
> That was Factory resolve which would have no way lasted very long. Factory
> went out of business shortly there after.
>
> In less than thousands of words, I made a plastic fixture to hold things
> solid in my Bridgeport milling machine. Snuck up on holes with a reamer,
> then a second one a few thousands over the first. Plenty of cutting fluid.
> I then machined a pin out of 416 Stainless Steel. Used precision pins to
> measure hole, and hand lapped .0008" oversized. Pretty good but fit was
> still not to my liking!
>
> Ends up that although when you ream a hole, you can measure a size, if you
> look at it under a microscope, it is not too close to smooth. I then made
> a series of pins in .0001" increments. Then I forced them 1 at a time
> till I could feel a good amount of resistance. Once you get to this
> resistance point, going larger does not change hole size. I will call this
> burnishing. After burnishing I measured holes, and made pins oversized.
> Not a trivial job making a pin holding tolerance to ~ .0002". Turn just a
> little over, then hand lap to precise size. I also lapped the center of
> pins a thousand or 2 undersized so the first hole would get minimal
> damage.
>
> Absolute no play, and I am pretty certain this is a permanent repair. Pin
> size was a little over .400" which was OKed by Andy.
>
> Ron Parigoris
>
>
> --
>
>
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