ive started building my second hollow timber board and, unlike the first, ive decided not to glass it on the inside to keep the weight down.
i have just had someone tell me i still need to seal the timber on the inside or the moisture will damage it.
is this true?
how will the moisture get into a sealed board? damage maybe?
i do have a vent plug so maybe there?..
i know there are people out there that dont seal there boards on the inside so id kind of like to know the pro’s and con’s…
cheers…
I can only go from my own limited experience and what I’ve learned from Paul and the other HWS builders here on sways.
Paul glassess the inside of his boards for additional strength, but I think that has a lot to do with the beautiful deck patterns made from thin strips of different woods, but I cant remember anything about him sealing the actual frame.
I’m sure if you sent him a PM he would be happy to help clarify that.
I used a single layer of faced ply to skin the deck and hull and felt the board would be strong enough with out glassing the inside due to the alternate grain of a ply lay up and from being a single pieve and not made from lots of thin strips.
I didn’t seal the frame or the inside of the skins and the board is still in great condition, I used water proof glues and external ply for the frame. If water ever gets in I’m sure it would do some damage depending on the amount and how long it is left but I think you would notice quite quickly. and would be salvageable if I were to open it up and let it dry off.
I think Paul had a storry about a crack along a cut lap that sucked in some water on one of his early boards 2# or 3# I think of the top of my head so it may be worth reading that.
I think sealling the wood could be a good extra precausion but it will add time and wieght to the board.
Check these guys out. They probably can help. The Tree to Sea Wooden Surfboard Builders Forum Forum Index
dfish
I think it is best to glass the deck on the inside!
Otherwise you put the wood under tension under your weight.
No one seals the insides of chambered wooden boards. I don’t see why a HWS would need to be treated differently.
My chambered balsa is just varnished on the outside (no resin or fiberglass), and haven’t had any problems yet… knock on wood.
cheers all…
i think your right woody. if my deck was any thinner, say 3 to 4 mm, i would definately glass both sides for the sandwich effect. as paul does.
my deck is 5mm so im hoping im gunna be ok.
also regarding the tree to sea guys. they dont glass the inside but there decks seem to be quite thick. maybe 8 to 10mm…
Hey Shifty,
Nice looking stick!
I can’t speak to the structural advantage of glassing your inside surfaces (because I can’t recall if indicated how thick your planks are), but with respect to moisture damage, if you used cedar (red or white) I don’t think you should worry about it. Cedar is extremely rot resistant and will most likely out last all of us (at least us old-timers). As far as short-term damage (ie. glue failure and/or plywood delamination), there is an “easy” solution - just dry it out thoroughly if she leaks.
Otherwise I wouldn’t worry about it. Hope this alleviates your mind 
glass inside and outside seems absurd.
with ribs 8" on center and 1/4" (6mm) decking makes glass almost pointless, IMO.
just a couple coats of epoxy and a vent plug and you’re golden.
one guy at Tree to Sea are using glass or just epoxy on the rails for added strength
and less for a seal, but that seems to be the exception more than the rule.
if you want to get fancy put vent plugs at the nose and tail so you can forcibly
circulate air through the board in the event that it gets wet.
venting, on it’s own, helps to normalize the internal air pressure and thus cut down
on the possibility of cracks and blowouts, keeping it dry on the inside.
My experience with hollow boards is they almost always get water inside at some point. That could just be me and how I abuse boards, and that I’ve only surfed about two or three-hundred hollow ones.
Vent plugs increase your chances of getting water in but they’re nice if you need them. Placement is important. Put them where water can easily get to them. I learned a trick to get the last bit of water out through the vent plug… feed a piece of cotton rope through the plug to let the water wick.
The three common causes of water getting into hollow boards are (not necessarily in this order):
• Damage
• Poor quality control
• Vent plug leakage
Do whatever Paul tells you to.