Building take-apart bulkheads

Builder's Forum
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I have a question for builders and users of nesting boats in general (I’m building an Eastport Nesting Pram) having to do with bonding the carriage bolts to the take apart bulkhead. As I possess a certain talent for complicating the simplest instructions, I’ve found myself wondering whether I should back up and start over, and so I’m asking others what they’d do!

To make a long story short, the instructions direct the builder to prepare the fore and aft bulkeads by drilling and filling the holes, then redrilling with a countersink to fit the bolt heads. When the time comes, the countersink is filled with epoxy/fibers/silica bonding mix, and the bolts (waxed)are pushed through and the handles on the opposite side are tightened down to ensure everything sets up straight.

In my build the bolts all set up straight, but I tightened them down too much, drawing the bolt heads down into the countersinks. Some of the adhesive oozed up around and over the heads leaving them partially buried, and by the time I figured out this had happened there was no way to back the bolts out without completely starting over, which I talked myself out of.

As I’d waxed the bolts only enough to make sure the ends in the aft bulkhead wouldn’t bond to it, and very carefully to avoid leaving gobs of wax where it wasn’t needed, I decided (hopefully) the overtightened bolts would have drawn some of the glue down into the bolt hole below the countersink, instead of just squeezing it out the top around the heads. When I checked the next day it seemed so: the oversized drilled-and-filled bolt holes in the fwd bulkhead were almost all nicely filled, which made me feel better about the “plug” of epoxy that’s supposed to be under the bolt heads being a little shallower than the designer intended.

I hope this makes sense first of all, and second, what would you do (besides cursing your carelessness)? This assembly has to deal with a lot of stresses and while I don’t want to overreact to a minimal departure from the plan, I don’t want the boat breaking in half when it’s not supposed to! Your wisdom is greatly appreciated.

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From what you've described I think you'll be fine.

The nature of epoxy and plywood construction tends to lead to success when things don't go quite as the  build manual suggests they ought to.

You epoxified your plywood bulkheads before insterting the bolts but erred in just how much 'tightness' was needed to hold everything in alignment as the epoxy cured? The effect of the overtight bolts ought to have forced epoxy well into the plywood fibers, enough to ensure that the ply's well-enough protected from mechanical forces as well as water intrusion once your project's launched.

Keep in mind you can always return to these fasteners and the manner in which they're fitted to your hull; if you think perchance you've not done it right the first time, by all means pull it apart & do it again!

There's nothing lost but a bit of epoxy and some time for the effort.