Sunday, December 28, 2014

Quick update

Just a quick update with some pics from last week. We completed fabrication of the four stainless hinge bases that will be welded to the hull to attach the down rigger poles and the forward support struts for the poles. The base plates are 1/4" stainless so we had to tack them down to some heavier plate to keep them from warping during welding. I found some 3/4" steel rounds that worked well for this. The heat from welding made the side plates want to warp as well. I had to use some threaded rod and bolts to get the assembly straight and square. In the end these came out nice and true, and the hinges operate smoothly with the Teflon washers in place.  We also jigged up the crows nest and tacked the basic structure together. After the holidays, we'll weld up the mast sections and start assembling the mast, cross trees, crows nest, etc. down rigger pole fittings and pad eyes are also ready to be welded up.




























4 comments:

  1. Nice Peter.

    That's the identical shape I used on fabricating my hinge pins. I already welded mine to the roof framing when I was building her. I started working on my mast, and as usual with all things boat building, I'm amazed at how big a project fabricating a mast is. Mine's no where near as complex as yours, as I'm just trying to get mine standing to hoist my yet to be purchased tender.

    Conall

    Conall

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  2. Hi Conall,

    I took my basic hinge design from the rig on the last boat we had. Seemed to work well. I definitely recommend having the downrigger poles (and any rigid supports) free to move on both up/down and fore/aft axis. This relieves a lot of localized stress on things as the poles load and unload in use. We're going to be doing a bunch of welding on the rig tomorrow so I should have more pics soon. Wish I had my design figured out when we were working with a bare unfinished hull- would have saved burning paint now... Are you doing the crows nest thing on yours?

    Peter

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  3. I thought about the crows nest, but I don't think I'm going to do one. I'd like to have a drone though.

    I'm turning bushings to weld in various places and have decided on turning them .006 over to try to not have to re bore. I bored and welded up the hinge joint on my mast/boom with the bore being .003 over... I had to re bore after weld up. I'm TIG welding everything.

    I did do some hull work during the build, so I'm hoping my paint burn will be to a minimum. I can handle burning off the outside paint, but I get a little testy when I'm burning inside paint from welding outside.

    I have my future paravane pole hinge pins welded in place and have a two arm design to brace the poles. Two pole braces per outrigger pole for fore and aft along with vertical. I think I skipped a roof frame between braces, so my pole braces should be 60" on center. I figure one of the pole braces will have to have a two way joint, along with a swivel joint on the pole . Two big, heavy duty ball joints would be nice.

    How tall is your mast going to be? What are you going to use for track for the steady sail? I was hoping to be able to weld or heli-coil some sort of track in place...I'd rather weld.

    Conall

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  4. We just welded the two pipe sections together, giving us about 24' overall on the aft mast. I think I've decided against the hinge/tabernacle arrangement in favor of a simple deck mounted socket to receive the mast. I don't really have a way to properly lay this mast down on deck if it were hinged, and things are getting complicated enough as it is... If I go this route, I will likely have some cheek plates welded to the mast step so I can pin the mast at the base and keep it from jumping out of the step.

    For track, I may go with standard 1.25" SS external track, with mast drilled and tapped for 316 stainless fasteners. Maybe with a UHMW isolating strip between the mast and the track? This size track conveniently matches with our neighbors sail rig, who we might inherit some parts from soon.

    Now I'm puzzling over winch type and placement for all the running rigging associated with the sail and paravanes.

    A lot of things to consider...


    Peter

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