Thursday, February 2, 2017

Off Center Board Part 2


The basic shaping of the board has been completed.  Per Dave Z's suggestion I roughed it out with a power plane (a vintage Skill 100!) which worked really well (thanks Dave).   I then used a 3x24 belt sander with the coarsest belts I could find - #30 - to finish the shaping.  Looks pretty good for me.









The wider leading edge is going to get a 5 foot piece of 1-1/2" steel round bar bedded and faired in with thickened epoxy.  Once that is done, the whole board will be wrapped in a couple layers of 10 oz fiberglass cloth set in epoxy resin.  The thinner trailing edge will be left flat and not rounded off.  Ideally, from a hydrodynamic point of view, it should taper to a knife edge.  But that would be fragile.  Also, if I rounded it off, this would create turbulence as well.  So it is best to square it off for the least turbulence.

2 comments:

  1. Nice shaping job. Wood surfboard makers do the same but to a finer degree..... and charge $1000 a longboard, usually.

    I never saw a reason Michalaks single offcenterboards wouldn't work on a larger scale save the brutish hardware involved. It always made a LOT more sense than a trunk and all its headaches and eliminated the flopping about of large traditional leeboards (which, to me, seemed entirely unseaworthy due to such huge mass being manipulated by a gale out at sea.... ripe for holing a hull or smashing a seamans hand). I am especially appreciative of your experimenting with leading edge steel protection that doubles as ballast.... if it works then so much nicer than messing with melted lead. Plus a super robust bottom scraper and grounding alarmer!!! Right on.

    Given your particular beam-length ratio it will be neat to see how your offcenterboard works out with such a large hull. If well I imagine longer and trimmer box hulls might do even better. Once I mentioned to Jim MIchalak, in correspondence, that many of his hulls would be awesome bluewater boats if blown up double and I meant offcenterboards and all. Now you're about to proof it. Best wishes on it.

    ReplyDelete
    Replies
    1. Thanks Robert! I have some confidence in this working out well. It seems beefy and strong enough, and once wrapped with the epoxy/fiberglass I think it will be very strong.

      We are once again snowed in with the biggest dump of the season yet. I can't leave the house at all, and likely won't be able to until the end of the week. But I did get my steel bar and got it glued to the leading edge of the board with PL Premium. I have epoxy and I have wood flour, so I'll be able to fair it in over the next couple of days. I'll post again once that's done.

      Delete