Cracked the nose of your board? Here's a video tutorial. Note that this assumes no damage to the foam underneath - just a small, mostly cosmetic crack.
Q cells are also known as glass microspheres, here. System 3 sells 2:1 epoxy. It's what I use and a bit cheaper than West. WEAR A MASK WHEN SANDING. Fiberglass is absolutely nasty stuff to breathe.
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...or you can save a lot of steps (added bonus– people will avoid you on the water).
The seabreeze thread is here (some helpful comments and clarifications): https://www.seabreeze.com.au/forums/Windsurfing/General/Board-Repair-Videos
More vids
Spray paint
Fin repair