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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