We highly recommend that you test fit your foil BEFORE you go to the beach to ride.
First, check your mounting hardware to make sure you have the right thread type screws to match the threads in the barrel nut of the foil. The screw should turn into the barrel nut easily by hand.
Remove the screws, and mount the foil into the board's fin box. Make sure the foil is all the way in, you can place one foot on the board to stabilize it and gain leverage.
Place the board on it's side and slide the bolts in. Check your screw length is correct. You want a minimum of 1/2" (1.25 cm), but no more than 1" (2.5cm) of screw visible above the board's fin box holes when the screws make contact with the barrel nut to ensure the screw is long enough to fully engage ALL the threads of the barrel nut. Use a large stainless steel fender washer to spread the load across the deck of the board. Do not use rubber washers under the fender washer as they just add play to the connection. Tighten the screws incrementally so the foil head comes into the fin box straight. Make sure you are using a screw driver with a good rubber handle that is the correct drive size for your screws.
Double check that your foil screws are tight. Flip the board upside down and rock the foil forward, then re-tighten the front screw. Do the same for the rear screw - flip the board upside down and rock the foil backward, then tighten the rear screw.
For the sturdiest connection lubricate the foil's Tuttle Box and the foil's components with DuPont Non-Stick Lubricant before connecting. This allows the foil and components to slide together well for the sturdiest and eliminating any wobble.
Troubleshooting
Mounting hardware does not catch the nuts when test fitting. Check that the barrel nuts are properly aligned. Often this can be done by looking down through the foil's screw holes and aligning the nut using a flat head screw driver from the sides.
Foil does not fit into the box. Do not sand or file the Tuttle foil head without first lubricating the foil head and finbox.
If the foil continues to be too tight, visually inspect the inside of the finbox for any obvious abnormalities like a blob of resin or similar, remove if necessary. Try again.
If the foil continues to not fit, only then should you use a straight edge to shave off the parts of the foil that are rubbing on the finbox and stopping the foil from fitting properly.
Mounting hardware does not catch the nuts and does not cinch the foil up into the board easily. Properly aligned foil screws should be hand turnable with no side pressure on the screw from the deck of the board or the entry hole into the Tuttle head.
Sometimes the screw holes through the deck of the board are not perfectly aligned with the standard 105 mm center-to-center Tuttle head screw spacing. There are two ways to correct the screw alignment problem. The first way is to ovalize the holes through the deck of the board so the screws can correctly align to the barrel nuts. This however is not the most aesthetically pleasing solution, especially with a brand new board.
The second method is to expand the angle of the entry holes into the Tuttle head so that the barrel nut and screw can be rotated to align better to the screw holes in the deck of the board. To do this, first push the barrel nut out the side of the Tuttle head, then insert a 1/4" (6mm) drill bit into the entry hole and side-ream the hole wider fore and aft. Do not expand the entry hole sideways. Re-insert the barrel nut and re-check the screw alignment.
A bit of time invested in checking the foil to board fit can save a lot of frustration at the beach when its windy and you're anxious to ride.
