I’m doing a hollow wood surfboard and I’m trying to find information on skin material. Most people go for Paulownia of course, Balsa or different “esthetical” woods like cedar pine and such.
I’m wondering if anyone ever used Lauan plywood for skins?? I see a lot of people using 1/8" dor the inner structure but nowhere have I found a place where they use it as skin. Why is that? most people think it looks ugly? is it a weight to volume ratio, and stiffness thing?
I don’t mind the look of Lauan, and at say 3/16 thickness it seems to me that it would be solid enough with proper glassing…
Lauan plywood, because of the thinness of the ply and the orientation and fibrousness of the wood grain, makes it almost impossible to sand smooth enough when under stress, like the curves of a surfboard. try a scrap piece and see if it works for you.
Isn’t Luan a super thin skin, one single layer in the middle and another super thin skin?
Basically as cheaply as a door skin can be made?
Seeing how easy it is to puncture a hollow door skin with a knuckle, I’d pass.
Pay the extra for marine plywood if you are going this route or watch your efforts swell, discolor, then disintegrate.
Aircraft grade plywood is built to even higher standards in regards to wood layering orientation and voids, and glue. $$$ though. Marine ply aint cheap either, at least not the good stuff.
If you really want to go Luan, I’d recommend sealing the interior frame and glassing the inside of the panels before attaching them to the frame. Luan is so thirsty it sucks a lot of resin, so its likely to pull resin from cloth unless it is well sealed before glassing. With epoxy, as opposed to laminating PE resin, this can lead to secondary bonding issues.
Many years ago A friend was using thinned polyurethane on a luan door for the first layer then several additional coats unthinned, while it was on sawhorses. When he went to flip the door over to do the other side the outer skin pulled off the center layer as the thinned first layer apparently destroyed the glue bond of outer veneer to inner core. He wound up gluing it back on but it was a full on curse fest, and failrly amusing from an observer’s point of view. Not sure what he used to thin the polyurethane,
I’ve just avoided anything to do with Luan ever since and will happily remain ignorant of best practices used regarding it.
Thanks all for the feedback, I’ll direct myself away from that choice of material!
I’m not finding close by supply of marine grade plywood in my area, specificaly thinner sheets. I can’t seem to find any Paulownia in Canada, from what I can gather it’s not so available in North America. I’ll keep on searching for my options!
Most Western Red Cedar C or better clear lumber, comes from British Colombia.
I’ve taken long road trips just to have enough selection.
It it Lightweight, stable, works well and smells incredible. Splits along the grain a bit easily. Thus the fiberglass on the interior and extra internal supports where knees and feet go.
I have used marine plywood. It’s way heavier. More impact resistant. Have to be weary of sanding through that thin outer veneer, and voids.
I get 5 planks from a 2x4 grade c or better, ripping lumber on a tablesaw. Wish for a quality band saw and fence and 6. Each slightly more than 3/16" thick. 4 of 5 them are bookmatches. 6 planks per side needed maybe a bit more.
Select lightweight( fishscale and hanging method) clear boards with acceptable character
Learn how to edge glue planks.
Or.
I tape planks together tightly with the green 3m concrete high adhesion masking tape, **flip panel over without stretching tape/ allowing seams to open… onto waxpapered flat table, then laminate them flat on a table pushing epoxy into the seams, then pulling cloth tight from middle. This laminated ‘homemade panel’ process can be taken to extremes, but a few stages can be combined.
Interior fiberglass on deck/hull panels, increases impact resistance greatly. Makes it much easier to seal the interior as well. One also gets to see the grain pop a bit earlier, and then not have rush to get to that near final stage of the serotonin blast.
When I started out building hws I used 5mm underlayment plywood for a few boards. It is definitely not the best material, but it is a cheap material for making mistakes when learning hws building. I also still use it for most of my hws frames. Depending on how you attach your decks and how evenly you sand you could end up with noticeable “grain” lines from the plywood plys. If that makes sense. If you look closely at the nose and tail of my boards you can see the noticeable unevenness I am talking about. Also with plywood be extremely careful not to sand through the top veneer.
I would say go for it, worse case is you make some mistakes and learn from them. Best case it comes out looking awesome and surfs great.
Thanks man! I’m still thinking about my options. But I like how it looks like it’s just one piece of wood on the deck and bottom that you get using ply. Very cool boards! I had not thought about the sanding issue with plywood go figure!
I use to be paranoid when I built my first foam boards that they had to be perfect… So much it held me back from making progress. Then you learn to like those imperfections :)
Home depot used to sell a balsa plywood that was fairly suitable for a hws skin. Luaun could probably be used if you glass both sides of the plywood, build with a closely spaced framework, and don’t have any shaping type sanding to do.
The Depot sells what theycall “Sanderly” ply in various thickness. Don’t know what kind of wood it is. Maybe Poplar? I have used the three ply 1/4" for stringers and fins. They sell a door skin that looks the same and is about 1/8"…
