I'm not angry at all, and don't think that any of my postings indicate that.Every street light in your town is bolted into helicoils or is a burial pole leaning.
Thread inserts in all industries are common. Your cell phone prolly has 3.
I think you just like to get angry.
Poly carb will bond to the hull with its alike Epoxy. The receiving hole will equal cast aluminum without the possibility of corrosion.
The 3D society is way friendly and patient that you imply.
In software the insert would cost 2.40 Canadian if the hull is 3” thick. Likely it’s 2” in poly carb.
On a group called Cults 3D you can link to 3D artists world wide. You can get a quote for any 3D part in any material. The owner is looking at a Fat 22$ bill plus postage for two inserts in poly carb. ASA and Nylon great marine plastics would not be appropriate.
In every corner of the planet is a 3D printer networked. Its jam packed with leading engineers. The very ppl who build the boat you sail are on it.
18 of these printers are at leading Yacht Clubs. Hinckley Yachts has one in their office. All for private use.
A fibreglass patch is equal to hammering in a cork. Would indicate zero knowledge of fibreglass.
I didn't question polycarb. Your original suggestion was carbon fiber, which would be a poor choice leading to problems.
Yes, I understand that lights and other things are designed with threaded inserts. However, a threaded insert used as a repair for something not designed with a threaded insert is a compromise over the original design, otherwise it would be designed with an insert. You are comparing apples to oranges in your argument - a designed insert vs a repair using an insert.
The fact that there are a lot of 3D printers around, as well as yacht builders having them, is a non-sequitar. Go ask Hinckley Yachts how they would approach this problem.
A fiberglass patch is far from being equal to hammering in a cork. Else you would have to declare that building the boat itself was compromised. I don't need to detail my fiberglass knowledge and experience, but I'd bet a donut it far exceeds yours.