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.
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Step 1: Get Supplies
Step 1. Get supplies. Cheap water-resistant sport watch with large display, suitable mold, clear resin, hardener.
Step 2: Prep Watches
Step 2. Prep watches, set time/mode, remove bands.
Step 3: Add First Layer
Step 3. Add first layer, 1/2oz each. Mix resin and hardener according to instructions on package. Pour a thin "face layer" and wait 30 minutes for it to gel. Otherwise, the watch will sink to bottom and will not be encapsulated properly. Use stir stick to remove any bubbles from bottom of mold.
Step 4: Add Watches and Second Layer
Step 4. Add Watches and second layer, 1oz each. Use stir stick and coat watch face with resin, remove all air bubbles. Pour a some resin on top of first layer, place watch in resin, move it around to dislodge any air bubbles. Pour in rest of resin layer. Watch should be completely covered. Let sit 30 minutes until this layer gels.
Step 5: Add Straps and Third Layer
Step 5. Add straps and third layer, 1/2oz each. There needs to be a way to strap the watch to your person, you should have figured out something to use and have it ready. I used the straps off a sleeping bag, they come with locking clips and plenty of strap. Use stir stick to coat both sides of the strap, removing as much air as you can. Place strap on top of second layer. Pour the rest of the third layer over strap. Wait 4 or so hours.
Step 6: Remove From Mold.
Step 6. Remove from mold. After the resin has mostly cured, 4 hours or more, it will shrink slightly and pull away from the mold. It should pop right out, perhaps with a gentle tug.
Step 7: Inspect Awesomeness
Step 7. Inspect Awesomeness. Two totally encapsulated watches for a total of about $50 (Two watches: $17 each, 1/4 of the $30 resin+hardener, found straps), they should meet all my dive watch needs. If the any of the watch is exposed, simply mix some more resin, place in the mold, and put the watch in on top. This should form a new layer and bond to the previous layers.