Hardware Bedding

The stanchion base is strong enough...is your deck strong enough ? To increase the footprint of the stanchion base , a backing plate... on top...between the deck and stanchion base is effective.

This backing plated could be constructed of a few layers of carbon or eglass laid over a flat surface, removed, cut to the profile of the base plus 20 percent, epoxy bedded and painted.

you have now increased the footprint load on the deck laminate by 20 percent

 

That's is one of the questions I had. What is the adequete laminate thickness around the stanchion base. There is a huge backing plate, the toe rail, but it was not used in the original design very well, since only the center bolt went through it and the two other bolts are even out of the area where there would be double laminate due to hull deck joint.

The new stanchion bases will have two bolts through the toe rail with 60 mm separation.

 

That must be a "Goiot " base... deck and toe rail fastened. they work. Make sure your deck laminate and profile are robust enough.to spread the compression load. An additional backing plate on the deck surface , under the stanchion base ,may be called for.

Most of the yachts Ive worked with for the past 30 years are metal. On alloy boats the most robust bases are alloy tubes buried into the deck then welded to a frame or gusset. The stanchion slides into this tube. Be sure that a plastic Insulator sleeve isolates the SS stanchion from the alloy tube. I dont know if a similar instalation is practicle on composite boats.

The rule is that stanchion always failes before the base.

 

No, I think the toe rail is from Pfeiffer (see picture, without the actual toe rail lip in the stern haf of the boat) and the bases I have bought are Niro Petersen and they will be boltet through the horizontal part of the toe rail. The two stern stanchions have a support leg thus they are firm lateraly, but not yet longitudinally. Maybe I need to add some packing plate beside the toe rail in the front two stanchion bases without support legs?