This board has a screw-vent in the tail, but it seemed to take in water from the vent, so I’m gonna caulk it tight. So I could open it with pliers if I had to let some water out, but basically abandoning it as a vent.
I added a breather vent in the nose, hopefully this will be a better solution. I don’t think this will ever be my daily driver, but I’d sure like to ride a few waves on it (no not monster waves), if my hip replacement is a success.
Is That a goretex vent, or are you going to thread in a thumbscrew somehow?
About 5 minutes after I get my 9’7" LB in the water, I unscrew my Vent to equalize, and once removed completely, it loudly draws in air for another 2 to 3 seconds through the ~ 3/8" aperture. Much depends on board temp before water entry and ocean water temperature of course.
If I just loosen the vent without removing it, it takes some 25 seconds to Equalize. if I completely remove thumbscrew I can EQ in about 8-10 seconds total.
I am not sure goretex could provide enough flow, and the partial vaccuum that occurs when the hot air inside contracts would have caused my board to gain more weight through dings/ pinholes in glass job in the 15+ years that it has been my goto longboard.
Goretex
I can’t find any info on just how much air goretex can pass and how quickly.
My experience with the thumbscrew vent taking a hot hollow board into cool water , just how much air it sucks in, would have me scared to rely on gortex alone. I would like my thumbscrew to have a goretex passageway for the cold board put in the sun with thumbscrew tightened down, but without knowing how much air the goretex can pass, and if it gets occluded over time I cannot have faith in its ability to protect the board from air pressure damage.
I’d rather just be vigilant with the thumbscrew, since I do not lend out my boards, or sell them.
The GoreTex vents I sell to all the distributors flow 500 ml / min. Grain has been using these in HWS since 2007 without any problems and they only use one unless it’s some monster flatwater SUP. Vents with the insert are $20 from Shapers Supply, get the retro-fit style and counterbore the flange to make flush. Why all the hassle and leak risk to make your own?
Thread for the vent are M12 x 1, the tap for this is more than the cost buying a vent.
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Thats cool! I did google surfboard vent, and that one didnt come up. If it had, I woulda been on it like a hobo on a ham sandwich! I just used what i had on hand, sorry. My bad.
Thanks for the flow rate figures.
In regards to a hot hollow surfboard entering cold water, and the air inside contracting forming partial vaccuum, how can a goretex plug on the deck, one filled with water, allow in any air to equalize pressure?
Obviously the compression of higher atmospheric pressure than interior board pressure is nowhere near as dangerous to the board as more pressure inside than out, and the Goretex vent can easily relieve the pressure of a cold board left in the sun, and I would certainly like that added level of safety, but I am not adding another vent. I would however be open to drilling a hole through my thumbscrew and having a gortex vent there.
The sheer volume of air that enters my HWSs when I unscrew the thumb vent after several minutes in the water is rather profound on a warm day with winter water temps. I usually Equalize the pressure more than once in between sets. It is cathartic.
If I open the vent in the water and hear no air rush in, then the board was the same temperature as the water when I closed the vent, or there is a leak.
The GoreTex vent is constantly equalizing, so there is no static pressure differential. A screw vent is not the same. The pressure will only equalize when you release the screw, so there’s always a differential as long as the screw is in. The GoreTex vent is never really submerged on the deck 100% of the time, but really a crush-pressure risk on the surface??? Most HWS construction can hold an internal pressure of 30 psi (or more) which means they could be submerged at an external pressure of 2 atmospheres (33 feet - 29.4 psi) without a crush risk.
No crush risk, but perhaps the pinholes in the glass job allow the wood to take on water with less pressure inside than out. I think it also effects the limited flex to some degree as well.
HWS’s might also have their volume affected as well, and significant knee or other impacts on the deck might be worse than if pressure were equal on both sides.
Logic and observation tell me that in order for the fabric to restrict water it has to be tight enough to impede air, while not restricting it. The vent would be constantly working to equalize pressure, but always behind in either direction. I can pressurize the board via the screw vent, plug it with my finger, and though the goretex is reducing pressure, i still get a rush of air when i take my finger off.
Pete C., thanks for the technical info about your vents. The flow on those looks much better than many of the imports.
Huck, thanks for the post. It took me a couple views to realize that you were ‘hacking’ a vented leash plug to get a vent-only setup. Sometimes I do the same thing (Japanese saw) on fin boxes to remove most of the plastic resin dam before sanding, so as not to heat up the box during that process.
I had a similar conversation on WBF
https://www.woodboardforum.com/forum/design/board-design-ideas/6661-vent-or-not-to-vent-or-gore-vent
As one result, there are two different types of goretex valves, regular and high airflow…
please check out: https://www.gore.com/news-events/press-release/venting-protective-press-release-high-airflow-us
the high airflow allows an gas exchange of 4000ml per minute or about a gallon per minute…
I bought them at an electronics supply site in germany and paid about 8 bucks for one vent.
I installed one in my new board, but it will hit the water next week first time…, hope it will work as it should, it will solve all the problems with forgotten valves in the past. And it will eliminate my concerns about how to use a valve, because if you just close it at the beach and head into cold water a vaccuum will draw the water inside if there is a slightest leak. In this case the vent makes things even worse. I had water intakes three times by now. The above described method of using the valve more often especially after some time in the water is wise, but only a working goretex allows for equal pressure at any time… If it works as it should…
