Optimum cloth weight?

Petros, well said. You have given me pause. Shadroe.

 

E-glass (electrical) - lower alkali content and stronger than A glass (alkali). Good tensile and compressive strength and stiffness, good electrical properties and relatively low cost, but impact resistance relatively poor. Depending on the type of E glass the price ranges from about £1-2/kg. E-glass is the most common form of reinforcing fibre used in polymer matrix composites.

C-glass (chemical) - best resistance to chemical attack. Mainly used in the form of surface tissue in the outer layer of laminates used in chemical and water pipes and tanks.

R, S or T-glass – manufacturers trade names for equivalent fibres having higher tensile strength and modulus than E glass, with better wet strength retention. Higher ILSS and wet out properties are achieved through smaller filament diameter. Sglass is produced in the USA by OCF, R-glass in Europe by Vetrotex and T-glass by Nittobo in Japan.
Developed for aerospace and defence industries, and used in some hard ballistic armour applications. This factor, and low production volumes
mean relatively high price. Depending on the type of R or S glass the price
ranges from about £12-20/kg.

.....again from the SP Systems old manual, you all should download it.
Very informative. I tried to find it fellas, but sorry it did not come up any more, Gurit own them now....mine is in pdf form if somehow I can get it to you