Surf Commission
 








Tech Talk

Q. What quad rear depth does my board need?

A. This is dependant on the depth of the fin box in your board.


The method of identifying what depth your box will take is to check if your board's box has a 'X' or the 'Future Fins logo' stamped out; as per example to the right.

The 'X' stamp indicates that the box will require a 1/2" depth fin, while the 'Future Fins logo' specifies a 3/4" depth fin.


As a general rule most quad boards are shaped with 3/4" boxes for the front fins, and 1/2" for the rear.

image of two fin boxes, one being 1/2'' with a future fin logo and the other being a 3/4'' box showing a X

Q. Why do boards have different box depths?

A.Generally, as is the case with thrusters, performance quads have a thinner tail, and consequently can only accommodate 1/2" boxes.

However more traditional retro boards have a thicker tail, and therefore provide adequate space for the larger 3/4" boxes.

Q. What makes Vector fins different from regular flat fins?

A. Vector foils create greater water attachment to the fin compared to flat foils. The more water attached to the fin the less drag and with less drag comes more speed.
More information here.

Q. Why is Future Fins the strongest fin system?

A. Futures has the strongest system out of any other fins system because its strength comes from its encompassing flange. This flange acts as a lap joint, which is similar in looks and in strength as an L-bracket. The perfect material ratio mix of the box and flange allows the flange to adhere to the foam and fiberglass when laminated.
Another key strength aspect is that Future Fin boxes are installed before lamination, unlike other fin systems that are installed after. By installing before lamination, Future boxes become part of the board that is being glassed, which keeps the boards integrity and becomes one single entity. Future boxes are not only the strongest fin system; its the lightest post-installation system on the market too.

Q. What is the reason why fins sometimes hum?

A.The short answer:
Pressure differences = Vortices or Turbulence = Vibration = Humming Fins

The long answer:

As water flows around a fin there are different pressures on each side of the fin. Water flows meet up at the trailing edge of the fin, and in cases with very different pressures, vortices or turbulence can be generated. These vortices push and pull on the trailing edge of the fin, causing it to vibrate. This vibration creates pressure waves or sound. Think of it as your voice when you blow air across your vocal cords.

Have you noticed that your fins hum at certain points while you are surfing, for example during a bottom turn on a fast wave? The vibration hum can be amplified or louder in cases of resonance. In fin terms resonance happens when the pushing and pulling from the vortices causes the fins trailing edge to move back and forth how it wants to move naturally. Or more technically, resonance can be defined as the circumstance when the force applied to the system is equal to the damping or resistance of the system at the systems natural frequency.

How do you fix it?:

Sand the sides of the trailing edge with a 100-150 grit sand paper (give it a few passes) and then surf it, if it still hums then give it a few more passes with the sand paper. The idea is to minimize the pressure difference at the trailing edge by sanding off any imperfections that may have been left from the production process. Make sure you don't sand too much, the more you sand, the sharper and more dangerous the trailing edge gets.

Q. How do you fix a stripped screw?

A. Step 1: Clean the box in question with a little fresh water to remove any sand or grit and make sure the screw hole and work area are clean and dry.
Step 2: When dry, use masking tape to cover the screw hole on the inside cavity of the box so the resin doesn't run out the bottom of the hole.
Step 3: Prepare the epoxy by following the instructions on the back of the package. Fill the screw hole with the Where 3. five minute epoxy. NOTE: Leave a little void at the top of the screw hole, to allow the drill to be started easier. Allow the epoxy to dry for a few hours.
Step 4: Use the #21 drill bit to drill a hole through the epoxy following angle of the original screw hole.
Step 5: Now use the 10/32 tap to re-tap the drilled hole following the angle of the original screw hole.
Step 6: Screw in screw and check for tightness, then go for a surf!

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