Where do I start to build window frames for the wheelhouse of a barge. My last material was marine ply this has failed, now to start again what do I need to know?

It depends what you want to make them from?? if its composites you will need some kind of master to use to make a mould.   You need to have a look at what design you are thinking of and how it could be made.

Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

Why / how did the marine ply "fail"  Most window frames I have seen on river barges (which I assume this is) were made from solid hardwood, well coated in ships-varnish, preferably two-component polyurethane  If maintained/cared for they will outlast you ...

If you want to make them from "composite materials" you could make them from thin strips of hardwood, laminated with epoxy, thus avoiding the "cross-ply" that will weaken a thin frame some.
 

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