by ozzie » Wed Jan 16, 2008 4:22 pm
G'day 1st knight. two lazairs lucky you,
I went down this path several years ago. if you think finding tedlar is difficult there try finding it here in Oz. In my search for a replacement i did the tests that you are looking at. i used several types of polymer products. from types used for food packaging, printing mediums, hothouse materials, even the types we print our money on. i made up small panels put them up on the roof and checked them every two weeks. it took less than a year before the polymer types used in the food industry failed completley. the glasshouse and material used for our money did a bit better. almost two years. the tedlar sample i used was a piece of leftover supplied with a kit. so it was pretty old before i used it. it lasted the longest but the tape failed. i found the tedlar impossible to find here so i went with mylar. i sourced an original roll from a lazair pilot in the USA. And this is in it's third year now and doing well. always stored and never left in the sun. But i sourced some from a new york company called Talas and ordered some that was a thou thicker than the standard type. This has been used on another lazair and seems much more stable.
it has less tendency to loosen off in the cold air. and shunk up much tighter. and has survived longer than the thinner type. the mylar may not last as long as the tedlar but it easily available with no questions asked. plus i just love the absolute clarity of it. I'll accept the shorter life and extra cost and time to recover when that comes.
Ozzie
BLUE SKIES AND FULL TANKS