How Is the Bobstay Tang Secured?

[Mark O]

The boat: 1991 C-30 Tall rig.

The issue: The bob stay tang bolts appear to be coming out, and the tang is not flush with the bow anymore. (see image) I'm not able to confirm whether the bolts are backed by a plate inside the hull or if there are threaded inserts glassed into the hull. (Called Catalina, no answer yet. Called catalina Direct, they don't know.)

My questions: 1) If it's through bolted with a backing plate, where the heck is the access for that? (I can't seem to get access other than the little hole in the V berth where the anchor locker drain's through hull is.) 2) If it's threaded inserts and they're stripped then what? 3) In either case, I’m unsure whether the bolts can be tightened safely under load without damaging the threads or affecting the bobstay’s current tension / length etc.Assuming I can take some tension of the forestay with a halyard, loosen the bb stay a bit and give it a try.

 

[Will Gilmore]

Mark, I don't know the answer to your question about backing plates or inserts. It seems likely the manufacturing process installed an embedded insert or backing plate during the hull layup and covered it when the internal bulkheads went in. Looking at a few images online, of the C-30 TR, it looks like there is a turnbuckle for tensioning under the bow sprite. I wouldn't release tension by that turnbuckle until the upward tension on the bowsprit had been released with the turnbuckle on your backstays.

The angle of pull from your bobstay looks acute enough that that plate isn't in danger of pulling its bolts out. Perhaps they are coming out due to a collision with a dock. If you can relax the tension, remove the old bedding and re-bed the plate, it might work to simply tighten the bolts. You should be able to tell when you tighten them if they get enough grip to remain solid. If you strip the threads, it will likely be that they were already stripped, or you wouldn't have been able to strip them just from re-tightening. In that case, you'll want to have a yard install a new backer plate anyhow.

Other options could be to re-cut the threads and go with a slightly larger bolt, or put in new inserts after drilling out the old whatever is in there. Does the C-30 have an anchor locker or does it have a glassed in collision bulkhead? You could possible install a new backer plate in a new location that you can get to.

Anyhow, here's hoping someone with actual knowledge of your boat chimes in.

-Will