TexasKayakFisherman.com est. 2000

Kayak fishing the Lone Star State...


By jmhall87
#1870008
Hi I'm looking to do a build thats between a sit on top kayak and a SUP so I can fly fish better I found places to buy the foam online but I can only find it available in 108" increments which is 9' due to my ehhh advanced size I'm thinking i'm going to need at least 12' probably 14'. Does anybody know where I can find foam in those deminsions? it's just when I do the math to laminate layers I'm not coming out much cheaper than just buying somthing similar to what I want? I was also thinking I'd mold in a seat/ice chest, then weld up a big aluminum rack for the back should be pretty awesome if I actually build it.
User avatar
By neon14
#1870382
Theres only one foam boat builder on this forum and he uses stuff from the hardware store in sheet form. I would try some surfboard forums. They make SUPs that are over 14 feet out of one block of foam I think.
By RealBigReel
#1903792
I don't think I am the only one on the forum that builds out of foam but there are also others out there building out of foam. Foam joints nicely with Microballoons mixed with Epoxy or Gorilla glue. Both are waterproof and stronger than the foam. Gorilla glue sands a little easier and you never have to worry about mixing. One problem with Gorilla glue is that it will foam up. Sometimes that is a good thing as it fills gaps nicely.
By TexaRican
#1903823
neon14 wrote:Theres only one foam boat builder on this forum and he uses stuff from the hardware store in sheet form. I would try some surfboard forums. They make SUPs that are over 14 feet out of one block of foam I think.


I think RBR inspired some others Neon :wink:

JMHALL
Sounds like you are looking carve something like a surfboard? You might want to experiment with the pink foam from HD. Pull the plastic off and laminate a couple of pieces together and see how you can shape it with different tools. I have been considering doing something similar myself. I don't recommend the blue stuff from Lowes though because it tends to tear out easier than the pink stuff.

Image
Image
User avatar
By neon14
#1903853
TexaRican, I had a laps of memory. I should have remembered that. Those are a couple of nice looking boats.
By TexaRican
#1903879
My feelings weren't hurt :lol: I knew you were referring to RBR. He's the pioneer of the house insulation foam boat!
By RealBigReel
#1903969
Any foam will tear if not cut with a really sharp knife. Blades should be replaced regularly. To prevent tearing leave the skin on and cut only part way through and take 3 or 4 passes to complete the cut. Use a straight edge like a Sheetrockers "T" square (4 ft) make the cut clean and straight.
The blue Dow Styrofoam density is 2.1 lbs/ cubic ft.
The pink stuff is manufactured by Owens Corning and has a density of 1.55 lbs/cubic ft.
They both sand like warm butter. I usually use 60 grit for shaping and higher numbers for finish work but 4 oz glass over a 60 grit finish will work just fine.
I do any microballoon/epoxy fill work needed right before I apply glass so the fill is still wet. This saves having to sand in between, and makes nice fillets.
User avatar
By Homegrown
#1904758
Sorry not trying to hi-jack, but will the foam adhesive they sell in caulk gun sized tubes work in place of the epoxy fillets? I've glued the sheet foam together with it before but have never gone back over it with glass and epoxy. Just curious as to whether the two are compatible.

HG
By RealBigReel
#1904849
Homegrown wrote:Sorry not trying to hi-jack, but will the foam adhesive they sell in caulk gun sized tubes work in place of the epoxy fillets? I've glued the sheet foam together with it before but have never gone back over it with glass and epoxy. Just curious as to whether the two are compatible.

HG


I have used that calk tube type foam adhesive. It is blue. It is inexpensive. It fillets nicely. You can glass over it with no problem. Couple of problems though. It will cut with a utility knife but sanding is difficult. It sands really hard, because it too soft. It cures slowly so you want to keep it as thin as possible. Would not recommend using foam adhesive for any kind of filler or for layering foam. If you need to fill use Gorilla glue or Microballoons with Epoxy. Layering is best done with Gorilla glue.
User avatar
By neon14
#1904895
I have a question. How easily do these boats dent? Like if you stood on the floor would the heal of your food dent it or do yall put extra glass or even wood in the cockpit area? Thanks
By RealBigReel
#1905115
neon14 wrote:I have a question. How easily do these boats dent? Like if you stood on the floor would the heal of your food dent it or do yall put extra glass or even wood in the cockpit area? Thanks

With just one layer of 4 oz fiberglass cloth it would dent pretty easy. One layer of 6 oz is much tougher but I use at least 2 layers of 4 oz all over and this even tougher. I use 3 layers in the cockpit and 4-6 layers on the bottom of the ends. The bottom is covered with a couple of layers of Epoxy with Graphite powder. This is nice aesthetically as it is shiny black, but it also provides protection from abrasion. If you look at the bottom of my kayaks they look all scratched up, but run your finger over the scratches and you can barely feel them. The bottom can be sanded lightly and the scratches will disappear. This also exposes the Graphite more and makes the bottom even slicker. I thicken the first layer of Epoxy Graphite with Phenolic Microballoons (dark brown). This fills nicely and gives better coverage. The second layer is plain Epoxy Graphite powder for toughness. This way 2 layers of Epoxy Graphite will be enough.
The ends of my kayaks are wood and the gunnels are covered with 1" corner molding. This provides protection in critical areas, with minimal weight penalty and the wood is nice aesthetically.
A foam kayak built like this would be much tougher than any Polyethylene kayak and a whole lot easier to repair.
I painted one foamy with exterior house paint. I wouldn't do that again. It doesn't wear well.
I painted the last foam kayak with Epoxy and mango yellow pigment. (Everybody knows that yellow kayaks are the fastest.) Pigment color is really good and coverage is adequate in 2 layers. The Epoxy and Pigment can be thickened with glass microballoons to improve coverage without harming the color.
One of my foam kayaks is 14'X28" and weighs 30 lbs with a vendor seat. The other is 15'X28" (plus rudder) and weighs 40 lbs (with a 5 lb error penalty). The only type of home built construction lighter would be Skin on Frame. Although there are some wood boats built here that are pretty spectacular in light weight.
Sheet foam is an excellent material to work with. It will form compound curves to a limited extent, at least much more than plywood. Cuts, shapes and sands like butter. Do need to avoid polyester resins, contact cement and CA glues but it bonds well with Gorilla glue or any sort of Epoxy. Is easily repaired and modified. It is readily available and inexpensive.
User avatar
By Homegrown
#1905386
Thanks RBR. Good info. Any chance you can share with us some pics of the foam boats you have built finished? If they are in here I can find them. I'm wanting to build a foam SOT and trying to decide which one.

HG
By RealBigReel
#1905423
Homegrown wrote:Thanks RBR. Good info. Any chance you can share with us some pics of the foam boats you have built finished? If they are in here I can find them. I'm wanting to build a foam SOT and trying to decide which one.

HG

My kayak STRIPER

viewtopic.php?f=71&t=181309

My kayak SANDY

viewtopic.php?f=71&t=158180

My Kayak HYBRID (Balsa and Kevlar)

viewtopic.php?f=71&t=148792&hilit=ultimate

Nice talking with you.

PA14 PVC distance?

Here's how I did mine for my PA 14...it's a little[…]

Question on Lure Rigging? What should the leader l[…]

Will throw in a nice stakeout stick for a full pri[…]