Re: epoxy resin gel coat issue
Ayuh,.....
I've always been under the impression that Gelcoat is a Polyester based coating,......
Just What is this stuff you're calling Epoxy Gelcoat........
Btw,.....
These Issues you're describing are the Exact Reasons I will keep on Painting boats instead of Trying to reGelcoat......
MAX GPE A/B MEDIUM SET is a two-component epoxy based resin system designed to provide a broad range of mechanical and physical properties that is suitable for almost all types of epoxy resin applications. It can be utilized as a structural adhesive demonstrating excellent adhesion to wide selection of substrates, chemical resistant or protective coating, impregnating and laminating for composite applications, potting applications for electronics and as a casting resin for large and small applications.
MAX GPE A/B MEDIUM SET is mixed two parts Resin to one part Curing Agent by weight or by volume (2:1). The mixed consistency is very low in viscosity, clear and easily poured or applied in to place resulting in bubble free castings. MAX GPE A/B MEDIUM SET has a 60 minutes gel time that allows adequate working time for casting, coating, bonding and potting or encapsulating applications.
MAX GPE A/B MEDIUM SET performs well as an adhesive for metals, alloys, plastic, wood, stones products, fiberglass, carbon fiber composites and concrete and other substrates that require high tensile shear strength properties. Higher adhesion performance can be achieved after a post cure cycle of 1 hour at 120oC.
MAX GPE A/B MEDIUM SET coating properties exhibits very high gloss, good color stability, high surface and excellent chemical resistance. Optimized amounts UV inhibitors, anti-oxidants and stabilizers are incorporated with the MAX GPE A/B MEDIUM SET to provide added outdoor durability. An aliphatic polyurethane coating should be applied to further improved resistance to UV degradation.
MAX GPE A/B MEDIUM SET can be used as a protective or decorative coating for metals, alloys, plastic, wood, stones products, fiberglass, carbon fiber composites and concrete and other substrates Higher coating performance can be achieved after a post cure cycle of 1 hour at 120oC.
MAX GPE A/B MEDIUM SET is an excellent choice for composite fabrication using fiberglass, carbon fiber, Aramid, and other hybrid fabrics. Its low viscosity allows fast fabric wet-out resulting in minimal void and laminant porosity. Cured composites fabricated with
MAX GPE A/B MEDIUM SET exhibits exceptional mechanical properties such as impact resistance, compressive and tensile strength. Higher mechanical performance can be achieved after a post cure cycle of 1 hour at 120oC.
As a casting resin and potting compound, MAX GPE A/B MEDIUM SET demonstrates good dimensional stability excellent electrical insulative performance and low coefficient of expansion and contraction. General mechanical properties are enhanced after a post cure cycle of 1 hour at 120oC.
Pre-Mix And Mixing Notes
Prepare all needed tooling and materials before mixing the resin and curing agent together. Pour the desired amount of resin then the curing agent in a clean container and gently mix with a spatula or mixing blade until uniform blend is achieved. Scrape the sides and bottom of the container to insure a thorough mix. Pour or apply the resin directly unto the prepare surface and allow to cure for at least 24 to 36 hours. The mixed resin will set-up in less than 2 hours and can be handled in 3 hours.
Physical Properties
Viscosity
900 cPs Mixed
Mix Ratio
100 parts A to 50 parts B by weight or volume
Working Time
65 Minutes at 200 Gram Mass
Peak Exotherm
160oC
Time To Reach Peak
80 Minutes
Density
1.10 g/cc Cured
Cure Time
1 to 3 days at 25oC
Heat Cure
2 Hours @ 25oC Plus 1 Hour @ 120oC
Set-To-Dry @ 10 Mil Film
6 Hours
Surface Dry
9 Hours
Handling Time
8 Hours
Mechanical Properties (1)
Test Criteria
Room Temp Cure
Room Temp + Heat Cure
Hardness
78 D
81 D
Izod Impact ft-lb/in
.13
.19
Tensile Shear Strength psi
3,100
3,765
Tensile Strength psi
9,600
12,300
Tensile Modulus psi
460,000
489,120
Ultimate Elongation %
3.8
2.3
Heat Distortion Temperature
84oC
110oC
Compressive Strength
12,300
13,000
24 Hours Water Boil
% Weight Gain
2.2
1.8
Electrical Properties (1)
@ 23oC
@ 40oC
@ 60oC
@ 100oC
Dielectric Constant 100 Hz
ASTM D-150
4.7
4.7
4.7
5.4
Dissipation Factor 100Hz
3.4 x 10-3
3.1 x 10-3
3.5 x 10-3
6.9 x 10-3
Volume Resistivity
Ohm-cm
5.0 x 1015
3.4 x 1015
2.6 x 1014
2.4 x 1014
Dielectric Strength V/mil
1/8 Inch Thick
558
(1) Cured 2 hours at 80oC plus 3 hours 125o
I am going to sand the epoxy with 300 and use a coarser grit on the bad areas and try again. Did anybody ever have a simular issue that can give me some tips. I am aware now i must have did a poor prep job.
