Mailing List lml@lancaironline.net Message #14264
From: Ian B. Crowe <ian.crowe@sympatico.ca>
Sender: Marvin Kaye <marv@lancaironline.net>
Subject: LC2 main spar bolts
Date: Thu, 04 Jul 2002 09:53:06 -0400
To: <lml>
A happy July 4th to all my American friends!
 
Firstly this is a thank you to Tim Ong and Mark Mahnke of Lancair for the speed with which they dealt with my problem yesterday.  It took them less than an hour.  Let's hear it for these two and the company that is smart enough to have them working there.
 
This is also a heads up to anyone who is putting the wings on for the last(?) time.  In brief I put on the right wing, no problem.  I ran the bolts up with a 1/2" drive ratchet, set my torque wrench to 40ft/lb. (Yes it is calibrated) and bingo there it was.
 
The left wing was no problem on the outboard bolt but whilst I could run the inboard bolt hard up with the ratchet the torque wrench indicated that the setting was below 40ft/lb and it would not reach the 40ft/lb however hard I tried.  I quickly deduced I had a problem and then the bolt stripped and was removed.  On examination it appeared as if the bolt had too long an unthreaded shank and had reached the end of the thread before reaching the torque required.  Put another way the grip length of the bolt was too long.  I had a washer under the head and the bolt is the bolt that came with the kit.  The repair procedure is no gift but I am not bitching as I had envisioned a dreadful tragedy and all I got was some inconvenience and a day's extra work.
 
My advice is that before you assemble the the wings to the centre spar, very carefully measure the parts that fit together and accurately determine the grip length required.  Compare this to the bolts you have.  It is permissible to use up to two flat washers under the bolt head. If this does not do the trick get the next shortest grip length.  Do use a torque wrench.  In my case I know that I cannot pull 40ft/lb in the space available.  If I had not used a torque wrench and had just used the 1/2" ratchet I would have flying with not only a slack bolt but a stripped one.  Makes you think doesn't it?
 
I will be pleased to pass on the repair procedure to anyone who needs it.  Misery loves company.
 
Regards
 
Ian Crowe
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