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Closed Compartments ( air pockets)

 I am not lucky enough to be flying my project yet, but I would like to share
some information on possible air pocket problems.  I spent much time working
on my canard and wings making sure the foam prep and glass work was good.
This included checking throughout the curing process and looking for bubbles.
I did find one or two small problem areas during the cure that were easily
fixed with weight, or at the worst epoxy injection afterward. One of my self
induced problems was getting a little too close with the heat gun and causing
the foam to shrink slightly ( about the size of a nickle).  This kind of dip
was easilly fixed by injection after cure. 
   An interesting thing I found on my canard was that it seemed to be perfect
( ie: no bubbles) untill well into the finishing process.  It was during this
fill and sand routine ( outside in my driveway) that I noticed something
strange.  The canard was coming along fine until I noticed some stange,
quarter sized bubbles showing up.  These were all in a perfect line and evenly
spaced. These bubbles Never showed up until the canard got warm out in the
driveway!.  I later determined that these bubbles were in the exact position
where I had used 5 Min. epoxy to hold the canard down. Of course I cleaned up
these areas before glassing, but apparently there was enough  5 Min. epoxy
left in the foam pores, to cause a small delam. at those points.  This was
also easilly fixed, but I wish I  would have known about that possibility in
advance.  NOW!!, I sand that entire (small) area out, and refill it with
pourfoam before glassing. It only takes a few minutes, and would save many
headaches down the line.  Hope this helps someone down the line.  
Kurt Winker
173 FGE