S.C.M. fenders, doors and roof??

[denegrader]

Hello to all who may know the question is to save weight G.M. used S.C.M. instead of steel.
Now t tops are avoided over a steel roof for added structural strength for handling and overall.
Now i found that theres a s.c.m. panel over the roof.
Question does anyone know what material is under the S.C M. sheet that bubbles on 99-2002 roofs?
Is it mostly steel for rigidity. and or what if anyone thinks they know or may know i'd apeciate knowing
thanx

[sjsingle1]

the panels are SMC......and its some funky glue that GM used to bond the top panel that causes the bubbles......the only cure is to replace it......do a search....there are many .....many....many........threads about it

[denegrader]

the panels are SMC......and its some funky glue that GM used to bond the top panel that causes the bubbles......the only cure is to replace it......do a search....there are many .....many....many........threads about it

ok i been reading them i also heard its for saving weight??
I dont think anyone really knows if under these panels if it is an actual steel roof and sail panel ??
also then why scm over steel to save 5 lbs maybe max???
If it is steel underneath??

[Cutlass]

Yes, its just like every other car. It has a steel structure/bracing underneath. And instead of sheet metal panel over it, it has SMC (Sheet Molded Compound) to save weight