1979-1993 & 94 Conv [Subscribe to Daily Digest] |
![]() | [Main C900 Bulletin Board | BBFAQ |
Prev by Date | Next by Date | Post Followup ]
Member Login / Signup - Members see fewer ads. - Latest Member Gallery Photos
Re: After having done quite a few f-glas repairs Posted by RS [Email] ![]() ![]() ![]() In Reply to: Re: After having done quite a few f-glas repairs, MS, Thu, 29 Aug 2002 15:32:37 Members do not see ads below this line. - Help Keep This Site Online - Signup |
Here are a couple of things to consider:
1 - Resin and steel have different coefficients of thermal expansion. Therefore, when the temperature changes, stress is put on the interface between the resin and the metal.
2 - Most fiberglass resins are more brittle than steel. Therefore, a level of stress that would have no effect on the steel will lead to resin fractures on the interface between the resin and the steel.
3 - After it cures, resin still shrinks because there are volatiles in the mix. It shrinks more on the side of the resin exposed to the air than on the side bonded to the steel because the volatiles excape more readily to the air from the non-steel side. You get curl and this eventually breaks the interface between the resin and the steel.
4 - Once the interface between the resin and the steel starts to lose its integrity, water gets in through capillary action. The steel rusts.
Like I said, fiberglass is a great material in the right application.
posted by 66.21.16...
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.
![]() |
![]() |
![]() |
![]() |
![]() |