Boat repair kit

I was looking at West Marine web site and they have a plastic boat repair kit that contains a thickened version of Gflex. Has anyone used this on a glass boat in combination with glass cloth? my wife paddles a plastic boat and I have a glass boat so I’m thinking about carrying this repair kit but adding some cloth to it so I can fix either boat.

Marine epoxy stick (putty) is what I

– Last Updated: Nov-14-15 10:43 AM EST –

have used in the field for repairs. Much less "mess" to activate and apply. Knead it like clay until its mixed then apply to the desired area. Hard cures in 60 minutes and doesn't need a dry surface or warm temp to harden. I've only used the PC-Marine brand but there are other brands out there. also, bring along a roll of Gorilla Tape.

cloth plus thickened
GFlex is use able. prepare to bear down into the cloth that is the surface needs support against your hand/spreader pressure. Use a commercial spreader.

I use epoxy under sheet metal for autobody repair, predrilling for pop rivits, riveting sheet into epoxy.

The Gflex thickened was a surprise at West, a parsec improvement over standard A+B. In a second repair with cloth over metal, used GFlex when the shelf resin had hardend. The wetting looks different than standard viscosity epoxy mixes but sets without bubbles or voids. Against a solid metal surface.

Is there a kit with standard viscosity GFlex ?

The thickened rates lower tenacity than the standard…why ? I dunno less bite or less applicability using standard methods ? less viscous fluids have more fluid carrier the carrier giving bite…MEK ?

MEK may or may not be added to thickened for more bite more viscosity…check with West and blogs.

Thickened’s working time with tubes bought from nautical Naples/S. Fla West Marine in a high heat humidity environment…specially mixed ? … had an easy 10 minute working time on a vertical surface with 85-90 degree temps, 75% humidity.

the putty stick
joins plastic poly boat cracks under duck tape ?

It will work
You are no doubt referring to the West System G Flex 655-K repair kit. There is also a G Flex 650-K repair kit which is somewhat misleadingly labelled “Aluminum Boat Repair Kit.” and I would recommend you buy that instead.

The epoxy resin and hardener in the 655-K kit come in separate toothpaste type tubes and have been somewhat thickened with colloidal silica powder (cab-o-sil). The resin and hardener in the 650 kit is unthickened but the kit includes some silica powder that you can use to thicken the epoxy if desired.

G Flex has been specially formulated to give an improved bond to plastic materials, however, if you are using this to repair a polyethylene boat you really need to pre-treat the hull surface by flame oxidation to achieve a satisfactory bond. This is easily done by quickly passing the tip of the inner blue cone of a propane torch over the surface. Flame oxidation is not required for repair of ABS or composite hulls. Here are the instructions for using G Flex from the West System site:

If you plan to use G Flex to wet out cloth you are better off using the unthickened version. G Flex is already viscous enough in the unthickened form. If you are using G Flex as a gap filler or epoxy glue to bond cracks, by all means thicken it up with some silica powder.

G Flex does not really offer any real advantages to conventional epoxies for repair of composite boats except for the fact that it can be mixed up in very small batches at a 1:1 volume ratio by eye. Apart from being more viscous, G Flex also does not cure clear. It is somewhat honey-colored when cured. Addition of silica powder will tend to give it an ivory color, depending on how much you add.

Apart from the fact that you really need to have a propane torch to repair polyethylene hulls with G Flex, proper repair of cracks in poly boats also requires guttering out the cracks to maximize the bonding surface and a thorough cleaning. For field repairs of polyethylene hulls it probably makes more sense to carry a roll of Gorilla tape and do a proper repair job when you get home. Any quick and dirty repair job you do in the field with quick set epoxy, JB Weld, or whatever, will make it more difficult to do a proper job later.

By the way, if you do want to go ahead and buy the West System G Flex 650-K kit, you can beat West Marine’s price by a fair margin:

carry tape instead
unless you are on a very long trip, repair tape is a better option for a field repair than epoxy.

a good choice is Nashua brand waterproof repair tape available at Home Depot. It’s an Aluminum tape with a blue plastic backing that you peel off. It’s about $18 a roll I think.

I have used this to repair a 3" diameter hole in a sea kayak while on the the water. I also patched a whole in my surfski for 4 months with no problem.