I'm curious if anyone has used one inch polystyrene sheet laminated on each side with FRP board to create a lightweight
sandwich for a front decking material requiring minimal support structure underneath?
Thanks for the response. Saving weight is a top concern.
I have searched, but have not found an example of dual sided FRP/Polystyrene laminate used on our boats. Am I understanding you correctly that you recommend using epoxy to join the layers? I can see where it would probably have better shear characteristics than warm contact adhesives.
My 1436 Alumacraft has height difference between the first and middle seat that leads me to believe I can lay the laminate material on the top of the middle seat, and add a lip to back part of the front seat. I suppose the only way to tell how much framing is needed is to build the laminate and then test the load bearing characteristics.
Definitely watching this one. I am curious how you plan on testing your composite. I’ve definitely gone the make it and see how it goes route, but with this kind of project I could see there being a lot on excess that could be used as test material.
What might be worth trying is adding some internal structure to your build. If you can cut some strips of the FRP and apply it to the cut edges of the insulation before sandwiching. You could also introduce some of these strips where heavier loads are expected.
Pulled some Q&A from HD on their product. Says that it is polyester based.
Q:Can these panels be glued directly to rigid foam insulation That has been glued to masonry walls?
bylando|May 26, 2021
A: Yes. But most rigid foam Insulation has a plastic finish on it and over time the plastic will start to pull away from the foam.
byThomas|May 27, 2021
A: Yes the panels can be glued as mentioned. Make sure that the foam insulation is listed as compatible with the adhesive used and that the adhesive is listed for use with the FRP Board.
byPV|May 28, 2021
A: Hi Lando, Make sure substrate surfaces are non‐painted, clean and dry. Wall surfaces should be smooth & flush. Please keep in mind that FRP will follow the contours of the substrate, so any major imperfections in the substrate may show through the product. Thanks, -Stabilit America
byStabilit|May 27, 2021
Q: IS THIS MATERIAL CUTABLE AND IF SO HOW WOULD YOU CUT
byTERRY|Dec 26, 2016
A: Unishear. Not every body has one & they’re not cheap. Very little dust, clean cuts & scrollable ( s-turns ) If you know a good tinknocker (sheetmetal mechanic) see if you can borrow it! They are the ultimate tool for FRP. Outlet openings... rotozip it w/ wood saber bit...holes... use appropriate sized holesaw. 100s of sq.ft installed,little dust, clean cuts,no itching or scratchy eyes!
A: Use a plexiglass or glass cutter tool. They won't have the same problems that a utility knife has, and they're less than $10. I'd buy both the one with a wheel and the one that looks kind of like a chisel.
A: Use good quality offset tin snips. Easy to set up and cut. Very precise control of cut. NO DUST! Make sure frp is not too cold. To cut out holes for outlets etc. start with hole saw or drill small starter hole with a conventional bit or paddle bit. Make sure that you have a scrap of wood below panel so that when you drill the hole, the frp does not break unevenly when the bit comes through the back. The drilling may generate small amount of dust. Once starter hole is made then use the left or right shears to cut the opening that you have marked out with a pencil or marker. This method uses less time when you figure in the safety prep, clean up and set up required for any sawing method.
byPV|Apr 8, 2021
A: I just re-did a huge commercial kitchen and here is what we tried. I started off by using a razor blade as other comments have mentioned and that was taking way too long. The blades were quick to dull and the tips kept snapping. We next tried a skil saw and yes its doable but you need hand protection and eye/face protection as this stuff once cut produces sharp small shards that give you insulation type itching and the projectiles are laser guided to go straight into your eyeballs. We next tried a jig saw which was a little better but the cuts were slow, a little jagged and very rough even with different teeth quantities. The ultimate best experience we had was using an oscillating tool. Wow. Very smooth and quick cuts on long strips, easy to free hand and cutting out outlet and switch holes was a breeze. Every power tool company makes one so just look it up on Home Depots website. The one we happened to have was a Porter Cable. I could care less on the brand you get but I cannot recommend an oscillating tool for this job enough. Happy Installs Folks!
byStevo|Jun 30, 2021
A: Skill saw and a shop vac. This stuff is very splintery so wear glasses, gloves and a (snug fitting) long sleeve shirt.
byDag|Jun 28, 2017
A: Use your plywood blade, turned backwards. Wear goggles and gloves. Same as you would do with thin aluminum.
byHopeithelps|Jul 27, 2021
A: I have been a building mechanic for years. Used this stuff everywhere you can think of because of its durability and longevity and I have to say that the only way to cut this stuff is with a 4"grinder and a cutting disk. Like a hot knife through butter. Also with a little know how and a torch or wheat burner you can wrap cylinders and corners, although I would not recommend this without a bit of practice in a non flammable environment.
byKnighttof7|Jul 1, 2021
Thanks for posting that info. I expect that the weight will be around 1.35 pounds per square foot. The encouraging thing is that my 1436 will only require roughly 42" square area to cover the front part of the boat.
The info on the plastic coating is good info...I'll be stripping the plastic off mine before I do the laminating.
I'd like to find some 1" in foamular 250, but there is only 150 available in my area. The FRP should spread my weight sufficiently. I guess only testing will tell.