My board has a 2 way valve with the brand name 2wayv.com.
What is the exact purpose of such a valve compared to the more traditional screw in and out valves used on windsurfers?
It’s Hobie’s version of a Gore-Tex membrane material sandwiched between two O-rings and clamped together mechanically. It’s a two-way valve in that the membrane will pass air in both directions but not water, so there’s nothing to open/close. At least that’s what it’s supposed to do.
thanks Pete.
my board is damaged and sea water got in the board.
obviously I am trying to get all moisture out but let’s say I can not get all the moisture out and I repair the board. would the valve let water vapor out?
You’ll never get all of the water out (see archives about this). You can remove the guts of the 2wayv vent so that you have a larger open area and then put the board in the sun, but watch out that the skin doesn’t get too hot. If you have a ding you’re repairing, grind it down to foam and put it in the sun. Position the vent hole or ding in a draining position and drain out as much as you can. Once it stops draining keep putting it in the sun and more will exit as vapor via the hole. With any membrane vent, don’t expect that water in the core will eventually leave as vapor; there’s just not enough air exchange at normal temperatures. If you disassemble the 2wayv vent, be very careful putting it back together or else you’ll wind up with even more water in the board.
Thanks Pete:
I spent a few days draining the board with the gash down then like you said once i ground down to foam and left it for two weeks. Using a fan intermitently to create some airflow (a tip from someone else) and left if for two weeks. I am sure there is still moisture in there but it does not feel much heavier than it used to so i started patching it up this weekend. Good thing is that whent the board gets warm the expanding water vapour can get out instead of damaging the board.
I unscrewed the vent but did not disasemble. Looks like it just screws back in…
Do you make any recomendations about these goretex vents and board bags (moisture in bag, inside hot car). In fact my new bag is pretty sweet it has an openening to release evaporating water vapor.
OR Any idea how much pressure is required to push water vapor through the goretex barrier into the board?
The vents I manufacture allow 5 ml/min airflow at optimum pressure/temperature differential, the one you have is similar. In normal conditions, it never sees this since it constantly is breathing and would require an abrupt change in temperature/pressure to flow at maximum. In the normal breathing condition, the amount of water vapor that can be held in the air during an intake mode is insigificant. I don’t know what the yield strength of the 2wayv membrane is, but the Gore-Tex I use is rated at ≥ 0.6 bar/60 sec. It is also tested to withstand IP65 - water jets, IP67 - 1 meter water submersion for 30 minutes, IP69K - high pressure spray. Keep in mind that this isn’t for the membrane, but the entire valve assembly as made by Gore. Since the 2wayv is a home-brew design using a piece of Gore membrane, you’ll need check with Hobie if they have those spec’s.