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This is the place to post your ideas, thoughts, questions and comments as relates to general boatbuilding and reconstruction techniques and procedures (i.e. recoring, epoxy, fiberglass, wood, etc.)
My original mast beam had two long bolts that went down through the mast step, through the beam and ended with a recessed nut on the bottom of the beam in the cabin. I'm wondering how necessary those bolts are, anyone know how tritons are set up? I know the beam bolts to the bulkhead, as does mine.
One thing I was thinking, is that perhaps the bolts don't need to go all the way through the beam. If the bolts went in a couple inches, even with out a nut on the end, it would achieve the same goal? What I'm trying to avoid, is weakening the beam by drilling holes all the way through, and worse, drilling large holes on the bottom to counter sink the nuts and washers. On the original beam, the nuts and washers sat in a 1 inch diameter hole, that went 2 inches up into the beam. That's alot of material to remove, at a critical spot.
Instead of through bolting, try using SS or Bronze lag bolts long enough to go into the beam a couple of inches. I had a boat with a deck stepped mast that was done this way. Never had a problem.
I laminated a new beam out of white oak and g-flex. I removed the aluminum mast step, removed the top layer of glass, dug out the Masonite core forward to the back edge of the hatch coaming and about 10" on the other 3 sides. I had some minor water intrusion into the Masonite, this is also likely what caused the delamination of the original beam. I don't think the holes weakened the beam, but provided a way for water to get into the beam over the years. Mine had water damage spread out from the holes and delaminated. No sign of cracking around the through bolts.
I replaced the core with solid layers of epoxy and fibreglass. I then epoxied a 12"x12" x1/2" piece of g10 from Mcmasters and Carr over the repair where the aluminum mast step sits. The mast step has 6 bolts. I over drilled these into the g10 filled with colodial filler and epoxy. After fairing, I drilled and tapped the 6 SS bolts for the aluminum mast step into this. No drilling into the beam, no through bolts to leak, extra reinforcement and the step is not likely to go anywhere. Just my solution for my Alberg 30.
If I understand correctly, you used 6 short bolts that didn't penetrate into the mast beam, just the tapped epoxy.
<the bolts were ~2" long tapped into the 1/2" g10 and into the deck but not through.
How wide an area under the mast step did you excavate? Did you stick to the perimeter of the aluminum mast step? Or wider?
<I ground flush the raised glass and foam that was under mast step and used the G10 to replace it and wider. The area I removed the top layer and glass was a few inches larger than the 12x12 g10 except forward, just to the hatch.
Did you do anything to beef up the support posts inside on the bulkhead?
<I made 2ea 3" x 1 1/2" x 4' beams and thru bolted them to the center two supports where the door attaches out of white oak. I removed the door. The beams I made are tapered from 3" to 1" top to bottom. I through bolted the main beam to the main bulkhead and to another 7/8" thick beam on the forward side of the main bulkhead in the v-berth. The forward beam was not laminated, although I thought of making my laminated one wider and slice off a section. My boat showed maybe 1/2" -3/4" compression on both sides of the main bulkhead. These two beams were both installed after I re-glassed the main bulkhead to the underside of the deck.
What is your opinions on laminating multiple layers of unidirectional carbon fiber onto your beam to prevent any further flex? i.e. what Steve did on his Commander (there is a post about his "strongback" mast support on this forum) I believe he had two 1/4" strips of what ended up being 20 layers of 9oz cloth, iirc.
