Reattaching Stanchion with no Access to Thru-Bolt

[BigBeakie]

Originally Posted by tkeithlu

That's a good idea for gaining more strength, BigBeakie. I'll remember that for the next time I'm in that situation.

The core of the problem is that the original bolts supplied more strength than a lag screw can. Whether the lag screw will be adequate none of us can answer for sure.

I wasn't thinking lag screw, the helical inserts are meant for regular bolt threads. So replace the original bolt with stainless bolt or cap screw or hex stainless screw or whatever head is suitable.

[Cheechako]

Originally Posted by Hudson Force

'but often assembled during a stage before other large pieces of the vessel were assembled and covering the access.

Yeah, although I don't remember seeing a boat with stancions on before the deck and bulkheads!

[Jim Cate]

Originally Posted by Cheechako

Yeah, although I don't remember seeing a boat with stancions on before the deck and bulkheads!

I believe that it is common practice to attach the deck hardware before attaching the deck to the hull. Saves a lot of man hours... and why would you not do so?

Jim

[Cheechako]

Originally Posted by Jim Cate

I believe that it is common practice to attach the deck hardware before attaching the deck to the hull. Saves a lot of man hours... and why would you not do so?

Jim

Because with stancions it's right at the deck joint, might interfere with glassing the two together I would imagine...? I have seen the nuts glassed over on some though.... so some makers do it I suppose...

[Boatwright]

1) If you have the width of an open end wrench for access, it is possible to glue or tape a nut into the wrench, work it into position and thread your bolt in from above. After it's torqued up wiggle the wrench free. I've used this trick more than once to place a nut in an 'impossible" spot. I've also heated and bent the wrench handle with a torch to fit around an obstruction.

2) Often what appears to be structure in the way of access is actually molded "headliner". Drill a 1/16" hole from above and see if it breaks through where you can see it. If it does, use this hole to center a larger work hole which can be patched with a snap in trim cover.

3) If you must work from one side, fabricate a nut plate a bit wider than the nut and 4 or 5 nut widths long. Cut a slot that will be hidden by your stanchion base as wide as the nut plate and long enough allow it to be inserted through the deck. Thread a stud into the plate from the underside. Rotate the nut plate 90 deg while moving it into position under the bolt hole. Pot the whole deal in thickened epoxy to anchor the nut plate and fill the slot. Fasten with a nut from above.

4) Where there's a will there's a way.

[NevilleCat]

I reckon the s/s inserts are the go.
Free Range Sailing have used them quite a bit around their refit; around 1:55ish...

Here