Thursday, September 3, 2009

Aft bulkhead holes fix

A Shields sank in Edgartown this summer, so the national class is asking fleet measurers to crack down on perforations in the bulkheads. One of the many things required on the Nationals entry measurement form is checking these out so they comply with this rule:

Perforations - Bulkheads
Perforations in the fore and aft bulkheads are permitted. Such perforations shall be made watertight while racing. One or two small holes not to exceed 3/8 inch in diameter may be drilled as close as possible to the top of the aft bulkhead to accommodate lines for trimming the backstay. (See Specifications 7.2, 10.1)

About half our fleet is in some small violation of this rule, and I let everyone know by email that some boats would have to fix this. Within about 5 minutes much of our fleet had gotten in touch with me by phone or email, kinda freaking out. Here are some fix tips:

First step when in violation of this rule is do not freak out and call me!

Second step is fix the holes. Old holes are easy, you can either fill them with epoxy, or close the hole up with a bolt and washer on each side of the bulkhead. 88 has a combination of these fixes.

The big stainless washed is covering the 1/2" hole left by the original backstay line. There is a 1/4" bolt holding the washers in place, with a nut on the back. Make this tight and put sealant below the washers.

The smaller hole between the 2 blocks has been filled and sealed with epoxy. The super easy way to do this is to wash out the hole with acetone, put tape on the front face of the bulkhead, then pack it with very thick epoxy or aggressive sealant from the back of the bulkhead. Let it dry, then tear the tape.

The holes where the line goes through are about 5/16" so we're fine there. If your line holes are larger you can make a gasket out of 1/8" plastic or G10, drill a 3/8" hole through it, glue it in place and clamp. Once dry, run your line through. Or, you can do the epoxy trick above, and then redrill your line hole.

Third step is really, really don't freak out and call me all at once.

Here are photos of how boats are in violation:




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