West System G/Flex Epoxy (2-4oz)
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|Compatible Material||Fiberglass, Ceramic, Plastic|
|Item Volume||236 Milliliters|
About this item
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- G/flex 650 is a toughened, versatile, liquid epoxy for permanent waterproof bonding of fiberglass, ceramics, metals, plastics, damp and difficult-to-bond woods.
- G/flex adheres tenaciously to difficult- to-glue hardwoods, both tropical and domestic varieties. This is important since many of the exotic and tropical species now being used to replace traditional woods present bonding challenges.
- G/flex has the ability to glue damp woods. It can be used on wet surfaces, even underwater when applied with specific techniques.
- Country of origin: United States
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WEST SYSTEM Specialty Epoxies
These specialty epoxies add even more versatility to the WEST SYSTEM line of epoxies.
WEST SYSTEM Specialty Epoxies
Six10 Thickened Epoxy Adhesive
Six10 Thickened Epoxy Adhesive is a two-part epoxy with a consistency similar to gel toothpaste. We manufacture it under vacuum to prevent entrapped air bubbles. Our in-house chemists formulated this toughened system with 8% elongation. Conveniently, Six10 requires no hand mixing when used with a standard caulk gun and the static mixing wand that comes with each cartridge (pictured caulk gun not included). The self-metering coaxial cartridge dispenses a gap-filling, structural adhesive that bonds tenaciously to wood, metals, fiberglass, and concrete.
Six10 has a working time of over 40 minutes until the mixing wand becomes unusable. This adhesive has shear thinning properties, which means it moves more like a liquid when you work the material. This allows its use in cooler temperatures. You can also use it to wet out lightweight fiberglass cloth. It will cure in temperatures as low as 50°F (10°C).
G/flex is a two-part, toughened epoxy that can make structural bonds which absorb the stress of expansion, contraction, shock, and vibration. We formulated this system for high elongation with an ultimate elongation of around 30%. The increase in elongation and lower modulus (stiffness) that it provides equates to better adhesion to substrates. This helps it resist a peel or delamination from starting.
G/flex has a 1:1 mix ratio by volume for easy measuring. It’s also ideal for bonding dissimilar materials. We offer it in two versions. The liquid version, G/flex 650, has a consistency similar to honey. You can thicken it with 406 Colloidal Silica to reach the same viscosity as the 655. The pre-thickened version, G/flex 655, has a consistency like gel toothpaste. With proper application techniques, it will bond to wet/damp substrates and dense or oily woods like teak and oak.
G/5 Five-Minute Adhesive
G/5 Five-Minute Adhesive is a two-part adhesive that will cure to a gel state within minutes. It has a 1:1 mix ratio by volume. You can wet sand it about 30 minutes after application. It is ideal for a temporary, quick cure that’s convenient for some applications like fabricating a quick custom sanding block with some scrap fiberglass cloth and a piece of foam.
G/5 should not be used where high loads are expected or if it will be continually immersed in water.
|Six10 Thickened Epoxy Adhesive||G/flex 650 Toughened Epoxy||G/flex 655 Thickened Epoxy Adhesive||G/5 Five-Minute Adhesive|
|Mix ratio, resin:hardener||NA (dispenses at proper ratio)||1:1||1:1||1:1|
|Pot life @72°F||42 minutes (in static mixing wand)||45 minutes||45 minutes||3-5 minutes|
|Working time, thin film @72°F||42 minutes||45 minutes||45 minutes||3-5 minutes|
|Cures to a solid, thin film @72°F||5 to 6 hours||3 to 4 hours||3 to 4 hours||5 minutes|
|Cures to working strength @72°F||1 to 4 days||7 to 10 hours||7 to 10 hours||15 minutes|
|Minimum working temp||50°F (4°C)||40°F (4°C)||40°F (4°C)|
|Hardness (Shore D) ASTM D-2240||80.6||75||75|
|Compression yield (ASTM D-685||9,690 psi||5,270 psi||5,270 psi|
|Tensile strength ASTM D-638||6,440 psi||3,440 psi||5,270 psi|
|Flexural strength ASTM D-790||11,300 psi||5,190 psi||5,270 psi|
WEST SYSTEM Epoxies
WEST SYSTEM offers high-quality epoxy resins, hardeners, fillers, and additives. Developed by our in-house chemists, our formulations are proprietary, structural, and marine grade. These epoxies have set the standard for epoxy quality in the marine industry and beyond since 1969.
An ISO 9001:2015 certified company
Founded in 1969, Gougeon Brothers, Inc. (GBI) formulates and manufactures WEST SYSTEM products. In 2020, NSF International recertified GBI's ISO 9001:2015 status, which ensures consistency in epoxy formulation, production, packaging, and instructional materials.
G/flex Epoxy Adhesive belongs in every boater's repair kit. Get a waterproof, flexible bond on plastic, fiberglass, aluminum, etc. The 650-8 kit gives you two 4 oz. bottles of the liquid epoxy. The 650-8 kit contains 4 oz. each of viscous liquid G/flex 650 resin and hardener. Mixing ratio is 1: 1. Mixed G/flex 650 is of a heavy "syrup" consistency. It will run off a vertical surface. 650 can be thickened with inert filling materials. G/flex is a product of West System, a division of Gouge on Brother's, The Gouge on brothers have been using epoxy resins in boat building and repair for some 50 years. It makes structural bonds that can absorb the stresses of expansion, contraction, shock and vibration. In addition to its superior bonding to many different materials and its ability to bond dissimilar materials, G/flex is much more flexible than other epoxies. This is an excellent property for boat building and repair. Polyethylene (HDPE) is a common kayak and canoe material. Its molecular structure resists gluing by most adhesives. G/flex solves the problem; it bonds well to polyethylene and ABS plastics. At 72 F pot life is 45 minutes. Working time is 75 minutes. It cures to a solid in three hours and cures to its full strength in one to two days. It cures faster in warmer temperatures and slower in colder ones. Clean up is simple. Wipe up spills with absorbent materials. Clean residue before it cures, with alcohol or acetone. G/flex adheres tenaciously to difficult-to-glue hardwoods, both tropical and domestic varieties. It has the ability to glue damp woods. It can be used on wet surfaces, even underwater when applied with specific techniques. G/flex does indeed belong in every boater's repair kit. The more you use it, the more uses you'll find for it - with your boating gear and other sporting and household items. It's easy to mix and use. The instructions that come with the kit are top notch.
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I then found a PDF on the internet where it states two different ratios, one using volume and one using weight. The instructions that came with the product make no mention of this, and now apprently the only solution is to try and heat the epoxy and literally try to pry and scrape it off, which I can assure you will trash the hull. So, thanks to West Systems lack of attention to critical details about their product, I can either trash the hull trying to fix the problem and eat what I paid for it, or I can just run it as it is, yellow gel coat, no paint.
My first regret of 2020 goes to West Systems
I got an amazing deal on a cracked Thule Motion XT box that the guy had driven into his garage without knowing the roof was too low & cracked it. I bought at night & when I checked in the AM, I noticed that the box was a few inches from being broken into 3 pieces.
After doing some online searching, I came across this & went to work.
It took a few days of minimal work but the end results are amazing. I'm generally good at stuff like this but had never really done anything with fiberglass or resin (patched a surfboard once 20+ years ago). I followed the directions & the end results are amazing.
How I fixed the box:
1) taped outside of box so the seams were as close as I could get them
2) rough sanded everything so there was plenty of adhesion.
3) used propane torch to heat treat the plastic (which I'm sure I did wrong as some of the plastic melted).
4) mixed G/flex & patched inside of box as well as I could & layered/coated cut dryer sheets to use hold stuff together (let dry for 24hrs)
5) took tape off, rough sanded outside
6) mixed some filler with the g/flex so I could use it like a bondo type material (I believe i used 405) - let dry 24hrs
7) sanded everything down & painted with rust-oleum painters touch spray paint from home depot
As it is, the box looks great from a distance. If I'd spent more time or had more experience, you wouldn't be able to at all but as it is, you can tell a bit if you get close. I'm still totally happy with how it all looks
Cracked box price on OfferUp $260
G/Flex, filler & paint: about $50
Total - $325ish
Cost from thule for new box $750
I did some bond tests with glass to metal to see if this would be good for optical element bonding. I made up some pairs of 25mm diameter 12mm thick plate glass and 50mm diameter 12mm thick pyrex bonded to 3/8" MIC-6 aluminum with 0.015" and 0.03" bond line thickness. I subjected these to temperatures ranging from -7F to 180F many times. There were no hints of any bond failure. The 50mm Pyrex with thin bond line is a particularly harsh combination considering the large CTE delta. Finally, I performed a lateral shear push-off test on one of the Pyrex samples, and the glass failed before the bond line, so Yeah, this stuff is great for technical bonding.
It entrains a lot of air with mixing, especially with fillers, so you might want to consider using a vacuum to de-air.
I measured Shore D 70 with my old out of cal durometer at room temp on a 4mm thick section. - like a medium soft plastic. At -7F from my freezer it measured D 80. In thin sections (5mm - 1mm) it's flexible and bendy - it won't break,