If TPU ends up not being rigid enough for you: I've had good enough luck with ABS coated in automotive RTV.

Thing with ABS though is that it's a special (not so)"solid" that gets softer as it gets hotter. My use had water in it when warm so wasn't too much of an issue, and it never experienced freezing temleratures.

Also it hasn't been 5 years yet. ~2 years and counting.

If TPU ends up not being rigid enough for you: I've had good enough luck with ABS coated in automotive RTV.

Thing with ABS though is that it's a special (not so)"solid" that gets softer as it gets hotter. My use had water in it when warm so wasn't too much of an issue, and it never experienced freezing temperatures.

Also it hasn't been 5 years yet. ~2 years and counting.