GRP Laminate Skin Thickness Calculator

Description

Purpose

This excel sheet helps the user to design the laminate layers of an FRP boat
From the rules/design, you may have achieved the total cured thickness needed for your laminate
Ending up with a thinner laminate means weaker laminate and thicker laminate means excess material is being spent
The user can try out various combinations of CSM and WR reinforcements to achieve the thickness accurately, along with other mechanical properties

Instructions for use
1. The table in IO-COMPUTE work sheet gives the following

• The collective thickness (except the gelcoat) for the number of layers of reinforcements used
• Ultimate tensile strength (N/mm2)
• Tensile modulus (N/mm2)
• Ultimate compressive strength (N/mm2)
• Compressive modulus (N/mm2)
• Ultimate shear strength (N/mm2)
• Shear modulus (N/mm2)
• Ultimate flexural strength (N/mm2)
• Flexural modulus (N/mm2)

2. Depending on the layer sequence of reinforcements you want to try, please select “CSM”, “WR” , or “None” for the fields in D6 to D15 as you want .
3. Accordingly change the value of specific reinforcement you have or want to use in E6 to E15
4. A default of 10 layers of reinforcements is given here, but you can use as many or as few layers as you want
5 . To add more layers, click the button “”ADD LAYER”” and a new layer will be added in row 5 and the layer numbers will change
6. To delete a layer, select “NULL” for “SELECT LAYER TYPE ” COLUMN
7. The table gives the total weight of the laminate, total thickness of the resulting laminate and the total glass content

Limitations
A hand layup process is highly dependent on the applicator and the results can vary from person to person

References

INDIAN REGISTER OF SHIPPING
Rules and Regulations for the Construction and Classification of High Speed Crafts and Light Crafts
Chapter 7 General Hull Requirements for Fibre Composite and Sandwich Constructions
Section 5 Material Properties and Testing