Shrink Questions on Infusion Job

General Composites Discussions Composites Talk
#1

Apologies if this has been answered elsewhere (i have searched).

We are getting shrinkage spots on a infusion job that is as follows;

stack;
Gelcoat
162GF
200CF twill
2mm Soric
162GF
200CF twill
peelply
bag

Vynil ester

mould, room and resin temp 22c.
980mBar pressure difference

infusion runs as per ususal but we get shrinkage at the ends of the flow path.

let me know your thoughts and thanks in advance

#2

How is the shrinkage manifesting itself? I can’t tell anything from the photos.

#3

Can it be that the gelcoat is thinner in these places?

Keep an eye onthe vinylester and the peroxide used. What is the peak exotherm achieved?

#4

Could be due to “wedge effect” where the fiber content is higher at the end of the flow path.