Building a pedestal for windlass out of fiberglass

Discussion in 'Projects & Proposals' started by chowdan, May 17, 2020.

  1. chowdan
    Joined: Jul 2008
    Posts: 104
    Likes: 3, Points: 18, Legacy Rep: 10
    Location: Seattle WA

    chowdan 1980 PAC41 Liveaboard

    Hey all

    I am looking at making a "pedestal" which will be used to raise my windlass up out of my anchor locker roughly 10"(give or take) so that the chain will be pulling parallel to the bow roller/anchor.

    The idea originally started with just making a slanted plywood base that bolts down, but the angle will be over 5 degrees which is not advised by the windlass manufacturer. I could have this welded up, but I enjoy working with glass and feel comfortable with it and thought it'd be a fun little project.

    The idea currently is that I would build a plywood mold which I can then lay up the glass in and put a male mold over and use clamps to clamp the entire structure together to squeeze out excess resin and air bubbles.

    The biggest question I am trying to figure out is how thick do I need to go? Considering the boat is a 42 foot sailboat and at last haulout we were 38,000lbs(for whatever a travelift scale is worth), I am thinking .25" would be thick enough, so doubling to .5" would be best. Looking at VectorPly's site, it looks like E-BXM 1708 open mold gives a thickness of 0.047" per layer so I'd need to do 10 layers in the layup.

    I've attached a drawing of what I'm thinking. I think the "feet" that would be through bolted on the floor inside the anchor locker(false floor - not where chain is stored) should not be 3" rather maybe more around the 4-6" mark each.

    Any opinions or advice anyone can give?
     

    Attached Files:

  2. fallguy
    Joined: Dec 2016
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    Location: usa

    fallguy Senior Member

    I would probably make the plug and open mould the entire thing. Make the flanges big enough and calculate the strength of the flange fastenings as well (glass tape and epoxy or metal)?

    Ten layers of glass will start to misbehave a bit, so the beginning layers need to be intentionally larger and lay largest first then trim later. In fact, I'd probably step each two layers say 1/4" or so. It will be easier to push air out that way, too. I might go 1/2" for twos. So, for 10x1/4"; you'd be making it 2.5" larger on the first layers at the flanges..

    Make sure to give youself plenty of radius as well, inside and out.

    You could try to build a vacuum mould, but hardly worth it.

    I am an amateur when it comes to moulds. Ondarvr is the guy here.
     
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  3. chowdan
    Joined: Jul 2008
    Posts: 104
    Likes: 3, Points: 18, Legacy Rep: 10
    Location: Seattle WA

    chowdan 1980 PAC41 Liveaboard

    Thanks fallguy.

    I haven't had to deal with moulds yet, but I was thinking i would overside it and then trim after the fact. Thanks for the little explanation on the oversizing(10x1/4" means 2.5").

    I was thinking doing a closed mould wouldn't be too hard to do with some clamps and plywood, but open mould would definitely be far easier to build and laminate up in.

    The drawings i posted were from when I was designing out the stainless concept, I am thinking that the "sides" would be angled(not 90 degree bends) to accommodate a better radius on the edges.

    For building a mould, i was thinking of doing it out of plywood and layering some plastic over it, but is there a better alternative?
     
  4. kapnD
    Joined: Jan 2003
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    Location: hawaii, usa

    kapnD Senior Member

    Melamine or Formica make easy one off molds.
    Doesn’t look like it’s going to show, so even packing tape over plywood will suffice for a quick mold.
     
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  5. chowdan
    Joined: Jul 2008
    Posts: 104
    Likes: 3, Points: 18, Legacy Rep: 10
    Location: Seattle WA

    chowdan 1980 PAC41 Liveaboard

    Thanks! The whole thing will just be lightly sanded and probably just painted white(maybe gelcoated). It will all live under the locker while the windlass will be pretty much parallel to the lid.

    I'm thinking that the two joints will be at around 45 degress to the horizontal surfaces. Shouldn't be difficult to build a plywood mould for. I need to finish my fiberglass water tank before i do this, but it will be pretty soon. Appreciate the quick response from both of you!
     

  6. fallguy
    Joined: Dec 2016
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    Location: usa

    fallguy Senior Member

    Anything you want for the mold that keeps shape well.

    ship tape like kapn says is easiest and won't float off on you
     
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