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 Laminating Foam Panels with Vinylester Resin

What the hell... I wanted to know what the alternative was anyway and what i learned I pass on here. This was my first choice in resin before I took advise I wish I hadn't took.

 These photos aren't necessarily in chronological order but do show the steps in order. The foam is 20mm thick, 4 X 7 foot and density is 80 kg, or 80 kg per cubic metre. This is a good density and thickness for decking which is what this will be for. Vinylester is less permeable than polyester, which doesn't matter much in this application, but is also reputed to be stronger than polyester. Epoxies adhere to this well, so no problem with joining to other work on the boat as long as epoxy is used as the joining agent. Here I am dipping out some resin.

There are a couple important tips at the end of this page!

   I was using small (to small really) batches. Here I have resin on a digital scale and am loading a syringe with catalyst. The mix is usually about 100:1. Knowing what I know now I would have been mixing about a kilo at a time but this one looks like about 400 grams.
   It really helps to wet the foam first. It doesn't have to be flooded, just wet.
   Then roll out the e'glass. This is 800 gram double bias. I'm smoothing out the glass with the roller.
   Roll it in to spread it evenly and to help it start wetting from the resin under it.
   Then pour on the resin. You can see that the glass is already partly wet from underside from when I rolled on it to spread out the glass.
   Now I've spread the resin around and have used my consolidating roller to remove any air under the glass. This type of consolidating roller or "cutter" as some call it, works best when flooded with resin. I used a squeegee to move any excess resin forward.

The small cutter works best in fine detail and when the resin is spread around to normal wetness. I have just used the squeegee behind my foot to push the flood forward.


I am using "peel Ply" (light weight polyester cloth) to insure a fine finish and had it pre measured like I did the glass and now roll it forward to cover the area just worked.

    And roll it on to smooth. You have to "work" the peel ply. Start from the centre and work outward and use your free hand to drag the cloth toward the edge to help eliminate wrinkles. You can wet the roller to help wet in the cloth and even to help wet the resin if you think you have a spot that is undersaturated. I like to use my consolidating roller over the peel ply too if needed and if time allows!!!!
   And if at the end of the panel you have more resin than you need... I keep reject papers for pushing the excess off before rolling out the last of the peel ply.

 OK... lessons learnt and tips... this stuff get sticky as hell. Toward the end of the panels it's sticky enough that it pulled the fine cotton thread out of the weave on the glass and ripped it out. This doesn't trash the job but it can leave a rough spot in the finish and it's damned annoying. The cure? After these were done I got in the habit of putting a length of PVC tape over the place where I was going to cut the glass and left it in place after the cut. That kept the cotton thread from being pulled up. It also helped keep the glass from loosing it's shape and making a bumpy surface. One person wetting, rolling etc, can work OK but the peel ply requires more time and stresses the situation.

I really disliked the sticky bit. Besides pulling out thread from the glass everything I touched stuck like glue to my gloves. It is about 60% of the cost of Epoxy and the vapours are not toxic to me. I thought it over and went back to epoxy for laminating after a few of these.


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