Thank you all of your kindly replies.

I am in HONGKONG.

One thing I want to made clear is that the PU I mentioned is formally called POLYURETHANE VARNISH, it comes with 3 parts to use, 2 PARTS OF B+ 1 PARTS OF A+ THINNER to apply as instructed. IS IT THE PU in USA the same thing as this?

I will try again to experiment with PU to cover silk on a LARGER area of framework sample to see if it held will onto it.(at least acceptable level). BTW, from last time experiment result, I can spray paint onto the PU covered silk but seeing grains, it doesn't varnished even I brushed as many as 5 times onto it. I THINK THIS IS ANOTHER IMPORTANT ISSUE WITH PU COVERED FABRICS.
Anyone have an idea to hide the grains to a level so as to have a gloss effect? (even if dope can be available and used)

Jim and JR,
Thank you for info about TITEBOND, do know that ELMER brand white glue is SIMILAR STUFF AS TITEBOND YOU MENTIONED, and if so, do you mean that can be used to replace DOPE as described. Also think you for info about CA, is it really not glow fuel proof? If so I will be in trouble, but it doesn't react for 10% which I am using, can WHITE GLUE used as fuel proof layer in fuel exposure area, like engine bay ?

Regards,

DL