So durning a boating session this railing came apart. The bolt that fountain used looked short it only stuck up about 1/2 inch. If you were to take a look at the other pics of the port side you can see that there is a lot of tenson on this end of the rail (like it was cut too short) anyways when I put a longer bolt in the after having someone else push down on the rail to meet the bolt while I was in that small hole with a custom piece ratchet I found that the threads in the rail were no longer gripping....now what?? there's not much space to do any type of work between the boat and the rail so?? I do have a new plan but I just want to hear what some else would do.

can you get in there with a TAP and tap it to the next size fastner?

Maybe a metric if its tight

Not trying to be obvious, but can you get the rail off the boat? Once it's off you can either tap the hole a little deeper, or drill and helicoil

both are great ideas but i only have about 2 inches of space to get any type of tool in under there without damaging the gel coat. I had a guy look at it to see if he can tack weld a bolt that will go down into the boat but the space was to small. I thought about taking the railing off but she is a 47 and finding all those bolts from the cabin side will be hard enough even if I can get to them there are a few behind the closet and head that hatch access is the only bolt i can see and that one is hard to get a wrench onto.

For my next trick i will try this:

Using a stainless steel piece of all thread that is a little smaller than the original bolt bent it into a curve or hook then hook it around the thick washer that has the bad threads on it then insert that into the boat and come under with a washer and nylon nut. once I have curved this piece i can cut and grind it to fit????????????

Try getting a metric self tapping bolt next size up and screwing it in.

thats what i'm going to try right there!

you could also go with a flat 1/4in think peice of steel,,,placed inside the rail that is drilled and tapped for any size bolt you need,,,kinda like a nut inside the rail,,,made out of the piece of steel

Are the rails ss? Is so be careful with jamming anything metric or self tapping in or you're gonna have a locked up mess.

Stick with me on this. Take a short piece of all thread, perhaps 3/8 and jam it into your hole from inside the boat. Drill and tap the rail from the side for two 10-32 grub/set screws. Tighten them till they mar the threads. Pull the all thread out, drill a hole where each set screw makes contact through the rod, then reinstall. Use longer screws to lock into the holes and then put a nut on the inside and call it a day

Love the ideas keep them coming!!! here are some more photos of the spacing and what is inside the rail I have to work with, that rail does pull up about another 1/2 inch. getting that peice of steel and the lineing up the new hole might pose a challange keep in mind once i go in the head with the wench i'm totally blind to where i'm bolting into. once i get the wrench on the bolt head im totally blind when turning it (whole forearm is in that hatch opening) I like the set screw idea drilling holes in the rail is my last resort I didn't want to have any hardware/holes showing on the out side.