I may be stating the obvious that it is not a good idea to leave the cling
film in place while the resin is curing if you intend to do any more lay
up's over the cured area. It is much better to use peel ply as this (a)
create a clean, ready keyed surface from which to work and (b) removes the
impurities of the resin/hardener reaction which migrate to the surface
during the curing process.(c) the peel ply draws out excess resin from the
lay up ensuring a lighter and stronger component.
If peel ply is not used then it becomes necessary the use abrasives and
solvents to remove the impurities, which in turn weakens the strength of the
lay up.
We used cling film quite extensively during the building of our Europa but
always removed it once the lay up was in place and then replaced with peel
ply. OK so it's a bit tricky to remove the cling film when the resin is wet
but we never found it to be a major problem. And even better method we
found was to use thin black polythene (as found in bin bags) as this way you
can see exactly how well the glass cloth is wetted out. It is best to
stretch the polythene over a piece of board using adhesive tape to stop it
---From moving around, then remove the polyethylene by cutting around the
wetted out cloth with a knife.
Carl Pattinson
G-LABS
----- Original Message -----
From: "Fred Fillinger" <fillinger@ameritech.net>track thou
Subject: Re: Cling Film = Release?
> I just pulled some release film this A.M. off a part, and here's some
> good stuff to use if you intend to do any more lay up'ssold in small
> U.S. by hardware stores selling "Do-It Best" house-branded stuff.
> It's doesn't feel like polyethylene, is translucent and matte finish.
> I wondered whether it would work at all. Jeesh. The stuff would fall
> off of its own weight if it weighed anything. The layup was even
> still tacky. Seems even like better paint drop cloth...
>
> Regards,
> Fred F., A063
>
|