<<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>>
          <<  Lancair Builders' Mail List  >>
          <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>>
>>
Ed Sikora asked about what to use for the shim between the main gear
rear bearing plate (GM ??) - aluminum ar phenolic.

First let me say that having 1/4 inch clearance back there at first
glance sounds like too much. I don't believe it is, and here's the
reason. When you're diddling that sucker into place to drill the bolt
holes where you want them, the extra wiggle room the 1/4" affords is
welcome. Of course, juggling an extra piece could be tough, but my
experience says it's nice to have some room to help get things adjusted.

As to the material to use, I'd use 1/4 in. phenolic simply because it's
easier to fabricate and I think it's lighter (by how much, don't ask!).
The shim is only in compression - something phenolic is suited to -
and you can bond it in once everything is lined up and drilled. Also
since it's only in compression, I wouldn't even bother to put any BID
over it. It ain't goin' anywhere once you pull up on those bolts.

No matter how careful you are in getting the distance between the
pivot bearings set up, when all is said and done, if you are a normal
human being, you almost certainly end up with around a gap of 1/8 inch
or so, i.e., fore-and-aft slop. Not so bad, really, but it makes for an
un-nerving noise every now and then as the horizontal shaft moves -
well, for and aft. Just cut a washer from the required thickness of
plastic like some of the stuff available from Aircraft Spruce - cut
out a little bit of the ring and snap it over the pin on the horiz. shaft.
Works for me.

Merry Christmas,

Santa flies a Lancair!

Dan Schaefer
N235SP