I am quite new to the forum and I would like to get some information on vent plugs.
I am presently building a hollow wood surfboard with cedar strips.
From what I saw on earlier discussions on the website, I now understand that I will need vent plugs for my Surfboard.
There are various products for venting a surfboard and I would like to get your comments on which are the best(Goretex, brass, including leash, etc.)for wooden surfboards. Thank you for taking the time to help me.
Hi Shawn, welcome to Swaylocks. I haven’t built a hws in awhile, so I’m interested to hear what others have to say. I have used brass, plastic, and goretex. Brass you need a screwdriver, so you’re not likely to neutralize pressure after you paddle out. You just surf with a negative pressure (suction), which can draw water in through tiny holes or cracks. Plastic are operated manually, so it’s easy to neutralize pressure at any time, but the seal is a little less secure than a brass plug tightened with screwdriver. Goretex operate by default, but you may need two in a larger board, they are prone to plugging of the fabric, and it is recommended they be replaced after a couple years. Interested to hear if there’s anything new and improved lately. Venting is one of the Achilles’ heels of hws.
As long as your structure has integrity you don’t need no stinking vents. If you can build a board to withstand outside pressure it will then withstand inside pressure. Some time ago In collaberation with Chriss Garret we built timber veneer EPS boards mainly for the Japanese market [shipped as air cargo] and as you should know EPS is about 80% air and these boards are basically two chambered when you consider the stringer right up the centre. Your average hollow board is chambered in what ? 30 chambers… something like that … Soo if your hollow board contains 100% air and is chambered 15 imes more than is an EPS core, how can it be said that one needs a venting? It’s an equasion that aint T00 hard to figure … Vents are just more marketing horse shit to keep you standing on the spot… not moving forward through fear of atmospheric pressure LOL. Chriss shipped dozens of our UN-pressurised vessels offshore and none of us EVER heard a pop.
I just put a gortex vent in the cedar strip board I am currenty working on. I set the plastic plug in a block of scrap and glued it to the inderside of the deck. after I glass, I will drill out the deck to the vent and touch up the epoxy around the hole. At least thats my plan. You can see a small pilot hole marking the center of the plug, just right of the leash plug.
Go gortex vent. It is working on keeping pressure equalized at all times. A micro hole around a fin box, handle, leash plug etc wil leak minimally or not at all with a board with equalized pressure. Warm board enters colder water causing an internal vacuum and micro holes will suck water bigggg time with out a gortex vent. A screw open/closed vent does you no good if closed off. Not practicle to have it open when you enter the water either.
Pic this morning no drama green room final coat of Deck on semi hallow/1LB eps foam frame paulownia board. Just pulled clay insert out of Pete C’s gortex vent after resin set.
Thanks Huck. It is a flatwater SUP built with Wood Surfboard Supply frame kit. 12’ x 30.5" x 4" Too late to install another one… I’m going to just have to trust the one.
I don’t know because I’ve never built anything near as big, but on the wood surfboard forum the SUP guys recommend two. I know from the boards I’ve made that the pressure differential can get extreme real quick on a sunny day going from cool water to dry sunshine, and back again. Don’t know how much air the goretex can process on short notice, but I guess you’ll find out if its adequate or not!
Foam E-Z makes this comment on the Casica vent with Goretex: “The vent will flow 40 ml/minute max, and SUP’s over 10’ or hollow boards should use two (mid-board & near tail).”
Atmospheric venting of hollow surfboards or sup's is critical. Without a functioning vent, your board will be vulnerable to structural failure due to (primarily) the expansion of air inside your board as the board heats up, which it inevitably does when out in the sun. The amount of pressure build up inside a board can increase to the extent that the board will actually pop! I know this to be true because it has happened to me. At first I wasn't sure what the sound I had heard was, but as soon as I got to the launch site and looked at the deck of the board and how expanded and rounded up the deck was I knew exactly what had happened. The board didn't actually explode but parts of the deck popped loose from the internal framework and the loud pop I had heard was the sound made by that structural failure. Oh man, did I feel horrible....I only had one board at the time, the surf was good and I needed this board!
I had installed two membrane (Goretex) vents and was confident that I had done the right thing. So what happened? The vents I had used were the Goretex membrane type. My comments are not about how "bad" the Goretex vents are, they are about the limitations of any membrane vent. Goretex vents will only transfer a certain amount of air through the membrane. The board I installed them in is a redwood board and what I hadn't anticipated with the redwood skin on this board is just how fast the darker wood would heat up. So even with two Goretex vents in this board, the pressure built up to the point of failure....so, POW!! was the result.
