As others have said, if you don't want to use canopy glue then use screws to attach the canopy wiht. However, buying a bottle of Formula 560 is only $3.69 from Tower Hobbies, [link]http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXCX70&P=ML[/link] . A bottle of this will last you for YEARS, so it's not a "one time application". I've been working off of the same two bottles of this canopy adhesive for over 10 years now. If you are going to attach a canopy this is probably one of the better ways to go because the adhesive remains a bit rubbery. This helps absorb vibrations from the airframe which keeps your canopy from cracking.

Ken