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Old 09-06-2012
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Re: Mast Compression

My Cal 2-27 has a similar, although less extreme, problem. And I have heard of other 2-27s having problems with the compression post. In the case of my boat, the CP was obviously deflected down by about a quarter if an inch, but there was no apparent damage to any of the associated wood. I loosened the standing rigging a little and that seemed to take care of most (but not quite all) of the problem. It appears that there are two problems: first, the design wasn't meant to be tensioned nearly as much as I, the previous owner(s), and probably most folks, tension standing rigging; and second, the design of these boats really didn't take into account the effects of 20, 30, or 40 years of bending stress/strain on that fiberglass box/beam that is supposed to support the compression post. On my boat I can actually see that the top of the FG box/beam has a bit of a dimple in it under the butt of the CP.

For the moment, I'm just going to leave the standing rigging a little looser. But, in the long run, I was thinking of slipping a steel plate (maybe 1/8" or 3/16" thick) under the butt of the CP (between the butt of the CP and the top of the box/beam, to distribute the load along a larger section of the box/beam), and/or installing some sort of support under the FG box/beam. In another thread, someone poured concrete (less than a cubic foot, IIRC) under the support for his boat's CP. In that thread the poster figured that it only added a hundred or so pounds, nice and low in the boat, and it spread the load out nicely. That might be something to consider, if the geometry of the area in question on your boat would allow doing so (but from your pics, it doesn't look like such a fix would be easy in this case). On my boat, the "concrete fix" might be a bit easier. But, it does have the disadvantage (besides the added weight) of not letting the hull and the liner flex independently of one another (which I think was one of the original assumptions of the design).
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Last edited by SlowButSteady; 09-06-2012 at 01:52 PM.
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