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Comment by Cliff Stripling on September 22, 2013 at 9:55am

Kevin - The Lexan is easy to work with.  It is tough, will not break, tear, crack, and bends easily.  You cannot do compound bends but they are not necessary.  I used several tools to work with it - tin snips, big fiberglass cloth shears, scissors of various kinds, files and sandpaper to smooth sharp edges.  When you drill you don't have to drill enlarged holes to prevent cracking like with acrylic.  I am using the .060 +/- thickness.  I forget the thickness number exactly but the standard is something like .040 (too thin), .060, and .090 (which is pretty heavy, harder to bend and more expensive).  I purchased a 4X8 sheet from a company that sells polycarbonate in Austin, Tx. and looked at and considered each thickness.  The medium one is what Zenith supplied with their kits.  Be sure not to cut too close to what you think the edges will be so as to leave plenty of edge for clamping and mistakes in measuring.  Once you have fit and drilled, you can mark and cut off the excess at the sides and around the top perfectly.  Work the forward curve first (obviously you have to cleco the forward fuselage skin in place at least temporarily) and establish the notches on either side as the windshield transitions over the top into the overhead canopy.  I made the "BEANIE" mod that so much has been written about.  That made the transition seamless and so smooth for air flow.  Even if you cut perfectly you will need a hold down bracket on the very front edge between the down tubes to keep the slipstream from getting under and lifting the front lip of the windshield.  Perhaps brackets half way to either side will be needed as well.  I have considered making a molded in place fiberglass transition lip to cover the transition all the way around... easy for me as I have all the materials for that on hand.  Hold down brackets are not pretty however they are made.  Good luck with your windshield/canopy.  You will find it a lot easier to do than you think.  Pretty fun actually and the results make your plane look a lot more finished.

Comment by Kevin McCune on September 22, 2013 at 5:37am

How well did the lexan conform to the bend and what thickness are you using.

Kevin