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VPS-F-3 Revision B 4-26-82

Varga Production Standard for Fiberglass Reinforced Plastic Fabrication

1.0 Scope:

This specification outlines the materials and step-by-step procedures involved in the fabrication of silicon fiber/polyester resin fiberglass parts in non- heated, non-vacuum fiberglass molds.

2.0 Materials:

The following materials only are acceptable for fiberglass fabrication under this production standard.

2.1 Polyester Resin: Tooling grade isolithic resins such as Koppers 6060, PPG #5180 or equivalent.

2.2 Fire Retardant Polyester Resin: Class II resins such as Dion #6693, Hetron #92AT or equivalent.

2.3 White Gel Coat: PPG or equivalent.

2.4 Black Gel Coat: PPG or equivalent.

2.5 Primer Gel Coat: RAM or equivalent

2.6 Mold Wax: Mirro Glaze MGH #8.

2.7 Mold Release: Rexco Partall Film #10.

2.8 6 ounce Glass Cloth: Hexcell, Trevarno #7533.

2.9 1 ounce and 2 ounce Fiberglass Mat: PPG.

2.10 50% Solution Methyl Ethyl Ketone Peroxide:

2.10.1 Norox MEKP -9 or equivalent.

2.11 White Pigment: PPG #55303.

2.12 Aerosil: Degussa Corp. Aerosil 200.

3.0 Fabrication (All gel and cure time period are based on 77degree F room temperature.):

3.1 Polyester Resin Bonded Parts (Except Wing Tips & Wheel Pants):

3.1.1 Coat working surface of mold with MGH #8 and buff.

3.1.2 On new or reworked molds, also coat mold surface with Partall Film #10 for the first part.

3.1.3 Catalyze Gel Coat of specified color (20cc per quart = 2%) and spray on to mold surface to specified thickness. Allow to gel 30-45 minutes (less time if room is warm, more time if room is cool.).

3.1.4 Place one layer of 6 ounce cloth into mold.

3.1.5 Catalyze Resin (6cc per pound = approx. 1.5%). This ratio gives the resin a working time of about 30 minutes at 77 degrees F.

3.1.6 Brush catalyzed resin onto the cloth layer and then squeegee out all the air and excess resin from the cloth.

3.1.7 Allow the resin to gel approximately 30 minutes (at 77 degrees) and then trim excess mat and/or cloth with a razor knife around the mold contour.

3.1.8 Allow the resin to cure at least 24 hours before removing the part from the mold.

    3.2 Fabrication of Wing Tips:

3.2.1 Perform steps 3.1.1, 3.1.2 and 3.1.3.

3.2.2 Place one (1) layer of 1 ounce mat into mold.

3.2.3 Catalyze resin (6cc per pound = approx. 1.5%)

3.2.4 Brush catalyzed resin onto mat layer.

3.2.5 Place one (1) layer of 6 ounce cloth onto mat layer in mold.

3.2.6 Squeegee out all air and excess resin.

3.2.7 Perform steps 3.1.7 and 3.1.8.

3.3 Fire Retardant Resin Bonded Parts:

3.3.1 Perform steps 3.1.1 and 3.1.2.

3.3.2 Fire Retardant Gel Coat: Make by mixing 4% PPG #55303 White

Pigment and 1/4 to 1/3 pound of Aerosil 200 with 10 pounds (one gallon) of Fire Retardant Resin.

3.3.3 Catalyze gel coat (20cc per quart = 2%) and spray on mold to .012 thickness. Allow to gel 30 to 45 minutes depending on room temperature.

3.3.4 Place one (1) layer of 2 ounce mat into mold.

3.3.5 Catalyze resin (6cc per pound = approx. 1.5%)

3.3.6 Brush catalyzed resin into mat layer.

3.3.7 Perform steps 3.2.5, 3.2.6 and 3.2.7.

3.4 Fabrication of Wheel Pants:

3.4.1 Perform steps 3.1.1, 3.1.2 and 3.1.3.

3.4.2 Place one (1) layer of 2 ounce mat into mold.

3.4.3 Catalyze resin (6cc per pound = approx. 1.5%)

3.4.4 Place one (1) layer of 6 ounce cloth onto mat layer in mold.

3.4.5 Squeegee out all air and excess resin.

3.4.6 Repeat steps 3.4.2 through 3.4.5 as required to obtain the specified thickness.

3.4.7 At attach points, compress attach area to specified thickness and flatness.

3.4.8 Perform steps 3.1.7 and 3.1.8.