Delete if in the wrong place but I had these GEBO hatch handles printed quite cheaply, around 15% of new part price...can get more done if anyone out there needs some...
Well done. The issue with 3d printing as far as I am aware is there are no structural reinforcing fibres included - so it is just plastic.
Your hatch handles might be fine for their purpose depending on the load cases expected of them - do they include any reinforcing fibres?
See the boat here...........nice effort but would you take it out into the ocean?
www.cnbc.com/video/2019/10/11/the-first-3d-printed-boat-built-by-the-worlds-largest-3d-printer.html
I believe there are all sorts of plastics and polymers to use with these printers. For what they have to do, they're more than strong enough. Quite thick too. I can't see them ever breaking due to strain of opening the hatch. How they go with regard to UV is unknown but at $8 compared to $65 plus I'm stoked!
Stick them on. It is just a cover plate with a handle isn't it?? (to let burglars in 
)
If they fail, what does it matter? You can still lock the hatch closed from down below can't you? That is all that really matters.
Apologies 3d printing with reinforcing is possible
markforged.com/learn/fiber-reinforced-3d-printing-what-you-need-to-know/
3d.markforged.com/white-paper-composite-design-guide.html
Pm me your contact details and I'll put you in touch with the guy that made them,
