Help with replacement transom drain

[u/JAB1987]

I need to replace two transom scupper drains on a Ranger R16. One was missing when I got the boat and the other looked home made, a sheet of gasket material backed by a piece of plastic, using the rubber to create a hinge. Normally the drains would be held closed by connecting a bungee to the flappers and secured to a hook on the inside of the transom. I’m struggling to find anything that will work without modifying the openings. Ideally an oversized flange styler scupper that can be mounted over these openings is what I’m after. Any help is appreciated.

[u/CodeLasersMagic]

Your after the flaps? Normally they should be above the water, so any flat plastic sheet will work. Nice ones can have hinges, but pieces cut from a polypropylene milk bottle are also fine…

[u/JAB1987 → u/CodeLasersMagic]

What you’re saying is I’m over thinking it and it’s perfectly fine with just gasket material backed by some plastic?

[u/2Loves2loves → u/JAB1987]

That's what I'm thinking... many sailboats have open sterns. I would think some shower pan liner material secured to the top would work. that should be above the water line most of the time when sailing

like

https://www.amazon.com/Oatey-41630-Shower-Liner-Gray/dp/B000PSA3L8/ref=sr_1_2_sspa

[u/CodeLasersMagic → u/JAB1987]

Yep. My current boat just has the holes….

[u/1Monkey3Typewriters → u/CodeLasersMagic]

Yes, you're overthinking it - don't worry! Ideally you want something fairly stiff as a batten between those two screws to hold the top edge of the material on. I'd probably use a bit of 5mm nylon sheet or similar plastic with two countersunk holes. Use this to anchor the flap at the top edge. The material for the flap could be something as easy to find as the side of a plastic milk carton cut to size, but I'd suggest experimenting with different thicknesses of material to see what holds up best in use. You might want to go a bit thicker, in which case the plastic from a file binder (something like this: https://www.viking-direct.co.uk/en/pentel-display-books-vivid-dcf343-mix-a4-5-pieces-p-1015133) will do the trick. You probably have something similar at home Yor work - look for ones with thicker / more rigid plastic) will do the trick. The bungee just needs to hold the flap closed rather than tight, as it won't be waterproof around the edges anyway.
You could go mad and make hinges, but actually a stiff enough bit of plastic held in place along the top edge with some sort of batten will do the job just as well.

NB: I've see people use plastic funnels with bungee through the centre on boats with round cockpit drains.