: My understanding is that it's in the way the fabrics are treated during
: manufacture. Some fabrics are heat set, essentially shrinking them before
: they are shipped. These fabrics will have little or no additional
: shrinkage capacity. Fabrics that are not heat set, such as aircraft Dacron
: (a proprietary name for polyester), will be shrinkable.

: Frankly, I've seen boats shinned with 3.7 ounce Dacron and there's no way I
: would trust it as a kayak skin unless I lived in an area where all the
: beaches are clean sand. The fabric is subject to lots of stress when used
: on an airplane, but it's not subject to cutting, tearing and punctures
: from contact with rocks, shells, logs and other flotsam. If the 13 ounce
: works out well, I may consider trying 8 ounce, especially if I can find a
: shrinkable fabric in that weight.

very interesting

so like you say, the plan would be to get whatever polyester cloth you want BEFORE the manufacturing process that heat shrinks, even if the fabric is not the greatest looking. By rights it should even be less expensive!

but if you could get a heat shrinkable glue,(is 1 or 2 glue coats of urethane shrinkable?)would doubling or tripling of 3.7oz in particular places work, i wonder?

-mick