[quote=traphappy]Often the holes are larger than the bolts on the new boats, but things stay put. The beam may sit well if you seat it in a thick vat of silicone, tighten down, and call it good. 5 minutes. Don't forget to put Tef-gel on the bolts to prevent the galvanic corrosion present on your beam from getting worse and to prevent your beam bolts from seizing in the threads.
Below is some more information, but I really think the enlarged holes are a non-issue so long as the beam is seated in silicone. I replaced beams once with new ones from the factory and the holes were very large. Yet, the beams never move. Boat is super stiff, nothing ever moves. This was on an Inter 20.
If that does not work, you might solve the problem by using epoxy to create a more form-fitting seat in the deck for the beam, without actually bonding the beam. Many racers fill the entire beam seat with epoxy, grease the beam (lard, I dunno; see old Catsailor threads for more info), and tighten things down to get a perfect fit. I would clean both surfaces thoroughly with acetone and sand to scar and clean again. There are many epoxies to choose from. West system products work very well. They produce reliable secondary bonds when many other things out there simply don't work. Cost is a consideration. Buying WS epoxy, hardener, and adhesive filler (to make it thick) is going to cost a pretty penny. You could use West System 610 (under $20 for large caulking gun size tube). It would be very good for this job for several reasons. It's thick like gel right out of the tube. Importantly, it mixes as it comes out of the tube. Thus, you will not have a pot of mixed epoxy flash on you before you are ready to seat the beam. You will want to get it straight before the epoxy sets, or else it will be a bad situation. To improve epoxy working time, you could work during a cool time of day (inside with AC would be best), shade the beams, and place the epoxy tube in a container or ice water (taking it out as you apply). I've done the ice water thing with other WS stuff, but you may want to try with 610 first to ensure it hardens, etc (although I'd be shocked if it did not).
You'll want to be sure epoxy does not creep too far into the holes or grab the bolt threads when you are seating the beams. You might put silicone around the holes and bolt threads before you put the epoxy down. After you seat the beams, you can remove them, apply some proper silicone (to waterproof and keep beam even more snug), and tighten the bolts.<!-- editby --><em>Edited by traphappy on Jul 27, 2019 - 12:51 PM.</em><!-- end editby --> [/quote]
