How to Install a Surfboard Vent

Venting a surfboard is very important if you have an EPS (styrofoam). This applies to other forms of watercraft too, such as standup paddle boards or windsurfing boards. Typically when you purchase a a premade board they are vented but if the vent get damaged or fails you will need to install a new one.

In this Instructable I retrofit a vent into my surfboard that was left in a hot car and the off-gassing of the EPS foam caused the surfboard to form a blister.

Here is a video for how to do the install. The written steps follow.

The vents I will be using is a combination Gore-Tex vent and removable plug. The nice thing about these vents is if you leave the plug screwed in it will still vent as Gore-Tex is a semi-permeable membrane and allow air too pass through, acting as a passive venting system.

The vents used are called "Milvent" and I found them on Aliexpress.

Materials:

• Vent
• Epoxy putty
• Liquid Epoxy
• Plywood
• Masking tape

Tools:

• Drill
• Hole saw
• Disposable Gloves
• Router or rotary tool

Find a hole saw that is the same size as the vent. Drill a hole in a piece of thin plywood, this will be used as a template to guide the hole saw as a pilot bit for the saw can not be used.

Tape or clamp the plywood to the surfboard with the hole aligned to where you want the vent to be installed. Typically you want the vent installed at the stringer so it allows venting from both sides of the surfboard with one vent. The stringer acts as a dam between the two sides of foam.

Mark on the hole saw the depth of the vent with masking tape. This will be your depth gauge so you know when to stop drilling.

Using a drill on low speed and on reverse (I find it's a less aggressive cut with a tenancy to not catch) start cutting a hole with the template. Remove the template once it's started and finish cutting the hole, stopping at the marked depth.

Take a flat head screwdriver to pry and remove the fiberglass from the foam and stringer.

Take your router or rotary tool, carefully remove the foam and stringer from the hole. It is possible to do this without drilling a hole first but I like that by pre-drilling the hole you get an even looking hole.

Test fit the vent and adjust the depth as required. You want a slight recessed fit so you can seal the top later with liquid epoxy.

Take some rough sandpaper rough up the vent so the epoxy putty will have lots of surface area to grab on to. Wipe down with some alcohol.

Cut off a small piece of plastic epoxy putty, the reason why you use this to install the vent is if you use regular liquid epoxy it will fill in the hole and will seal the foam.

Knead the putty to mix the two parts, use disposable gloves. Wrap the putty around the vent and push it into the hole. I used a wooden board, socket and clamps to hold the vent down until the epoxy putty hardened.

Once the epoxy putty has hardened, remove the clamps. To ensure a water tight seal, some liquid epoxy was used to seal the seam around the vent and surfboard.

First some tape was applied to keep the liquid epoxy out of the vent. The inside and outside hole was taped to ensure no epoxy could leak.

Some liquid epoxy was placed over the seam of the plug and board. Try to keep it as even as possible.

Let the epoxy set until it is mostly hardened, remove the tape before it fully hardens as it makes tape removal much easier than if you let it full harden.

Sand to blend the epoxy.

Install the plug into the vent with a socket.

Vent is installed, go surfing!