Originally Posted by redbopeep
That sounds sort of right. Sealing it with epoxy so that NO water can penetrate the core is paramount. There's also another issue of having sufficient strength in the equipment/deck/backing plate sandwich so that your deck isn't damaged by a load on the deck mounted object and doesn't flex due to such loads. Often manufacturers of equipment will have a couple nice drawings/installation plans depicting how to do the job right. What are you installing, btw?
Yes to the backing plates! I have a lucky access to stainless or aluminum plate I will take full advantage of, with holes precisely punched rather than drilled.
The starboard side of the cabin top, the PO put in a deck organizer and a three-banger rope clutch. He rigged main halyard, first reef, and topping lift to it. Then he moved the associated winch back a foot allowing him to reuse the holes for the rope clutch.
This setup works very well. I want to do the same on the port side and rig the mainsheet, the jib halyard, and the spinnaker halyard through it. I might also take the #16 two-speed winch off the mast and use it there in place of the #8 single speed I have now. The mast winch has no other use.
The good thing is that I can look at what was done on the other side and make sure I have created something at least as strong.
So some of the holes I need are already there. Some of the existing holes will need to be filled. I can afford to take my time on this and will probably space it out over the next few months, ensuring that everything is correct and minimizing the missed sailing opportunities.
Meanwhile, product or method recommendations will be taken to heart.