Message-Id: <3.0.3.32.19981113172503.02d32b84@olsusa.com>
Date: Fri, 13 Nov 1998 17:25:03 -0500
To: lancair.list@olsusa.com
From: Marvin Kaye <marvkaye@olsusa.com>
Subject: Jack stands
Mime-Version: 1.0

          <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>>
          <<  Lancair Builders' Mail List  >>
          <<<<<<<<<<<<<<<<--->>>>>>>>>>>>>>>> 
>>
I learned a difficult lesson this week that I thought I should pass along
to everyone.  If you've gotten to the point in your construction process
where it's time to be able to hold your airplane up off the gear and you're
thinking about a temporary jacking setup to support the fuselage, be sure
that whatever it is you come up with is solid, stable, and as close to a
one-piece device as possible so there's no chance that a nudge or a knock
could put the entire thing off balance.

When I got to the point where I needed to be able to move the gear up and
down to set the hardware for the gear doors I came up with a stand which
incorporated a pair of pedestals onto which a pair of bottle jacks could be
mounted.  I fabricated some wooden pads with the locating pins for the jack
points in the fuselage which have a recess in the bottom to accept the top
of the jack shaft.  I inserted the entire thing under my airplane, jacked
it up in the air, and everything has been fine for several months... never
a sign that indicated there was a catastrophe waiting to happen.  Well, a
few days ago the jacks decided to lean backwards without my noticing and
the next thing I knew the jacks were on the floor and the fuselage was
sitting on the pedestal.  In the process of spitting the jacks out from
underneath the airplane one of them got caught between the pedestal and the
fuselage and broke through the outer bid layers in 2 places, leaving behind
a couple serious gashes from the jack base in the bottom of the fuse, about
4" in front of the main spar just inboard of the jack points.
*(#)$_!&(@#!!!  (Had I drilled the bases of the jacks and made them a solid
part of the stand by bolting them in place this couldn't have happened...
one of those instances where the job was almost finished but not quite.)

For the last two days I've been fabricating the all steel jack stand
advocated long ago in the LNN, a picture of which has just been added to
the attachment section of the LML home page, one of the photos courtesy of
Jens Jensen.  Another few hours and it's going to be completed and I can
rest easy knowing that the fuselage will have a good and solid support from
now on, one that won't collapse when I least expect it.  

The moral of the story is be smarter than me and build as sturdy a support
system as possible... don't cut corners!

    <Marv>