Creating A Replacement Cap For Our Pool

Project:
Making a little plastic cap to keep the air in our small paddling pool

Difficulty Level (Easy, Medium, Hard, Insane):
Easy

Process:
It was July 1st and almost warm enough to put out the little paddling pool for the kids so I hauled out the air pump and got going just to realize that one of the 3 plugs that keeps the air in for the pool wall was missing. I tried a regular pop can cap but it was too big and no other bottle had a cap that was just the right size.

I realized I could probably just go to walmart and buy one for a couple of bucks but where would be the fun in that? So I hauled out the alginate and the two-component urethane casting resin (both from www.smooth-on.com) that I bought a couple of years ago after the Fix that wasn't fiasco.

The first step was to create a negative mold of the bottle cap using the alginate. Then, I had to mix the two components of the rubber and pour it into the cavity. An hour later it was de-mold time, clean up the edges and cap the pool

Pictures:

One of the other caps

Inside of cap

I used a piece of silicone gasket (red) to replace one of the missing stoppers

This is what it should look like

The rubber stopper that is still missing the screw-on cap

After I poured the alignate (the cap is at the bottom of the tin can)

The two urethane components before mixing

After I poured the urethane into the alginate mold

Second try as the first try didn't work out

After I de-molded the cured urethane

After it was cleaned up. It looks pretty ugly but it works

After I installed the cap on the pool

The pool all ready to be filled

Tools:
Belt sander
Knife
Screwdriver
Dental pick

Materials:
2 tbsp Alja-Safe Alginate
1/8 cup Smooth-Cast 380
Some tuck tape

Cost:
$0.00

Time:
1hr

Savings:
$2.50

Conclusion:
Works great. The air is holding.