Friday, February 5, 2010

Bulkheads: Thru-bolting

I was thinking about the bulkheads and the loads they might be subject to in a storm. They had several layers of cloth tying tying them to the hull but the bulkhead is made of plywood with the final ply being two millimeters thick. I could imagine that thin ply shearing from the rest under a severe load. The more I thought about it the more I felt I'd better "beef" em up. Drilling through the glass tabbing and thru-bolting seemed to be the logical thing to do, even if it wasn't necessary I'd sleep better at sea knowing it was done.
So it was I found myself scrunched in lockers with drill in hand, boring holes in the bulkheads.
The plan was I'd bore several holes along the bulkhead, vacuum up the dust, then push a 5/16" cap screw (bolt) through the bulkhead with some 5200 and a big fender washer on it. My helper  would place another big fender washer on his side of the bulkhead and then finish up with a nylock nut and tighten it down.
This procedure was going along very smoothly, after all I had built the interior so I knew were everything was and could just go along drilling without checking the other side of the bulkhead for wires, obstructions, etc.
Imagine my surprise when I drilled through the forward settee bulkhead, pulled back the drill, and out  poured a geyser of water! The look on my face must have been priceless, there were no tanks there and the water system was dry, having never been filled. How could there be water!  My helper took one look my expression and burst out laughing and yelled "shes taking on water! abandon ship!" as he dashed off the boat for some rags and a bucket.
I'd forgotten I had placed a row of one gallon water jugs in the locker to ensure they would fit and had neglected to remove them and drilled right into one. Fortunately we had made the locker water tight and sealed the wood so the water was contained and all we had to do was mop it up and run a fan on the bolt hole for a day to dry it out. The rest of the bulkheads were bolted without issues.....I looked before I drilled.

1 comment:

Anonymous said...

Great idea!
And a funny story to boot.
No wonder you're my best friend, eh?!