Problem: I spend long hours underwater at shallow depths and I need to keep track of the time.
Parameters: I don't need the fancy features of a $500+ saturation dive watch, however the cheap "water resistant to 50M" watches are not up to the task. I don't even need the features of the cheap watches either, I just need something that will display the time and not get destroyed by a few hundred hours at 20 feet.
Solution: Encapsulate a cheap sport watch in clear polyester resin.
Step 1: Get supplies
Step 1. Get supplies. Cheap water-resistant sport watch with large display, suitable mold, clear resin, hardener.