Just got my study plans! Woods Sango

Discussion in 'Boatbuilding' started by WoodSango, May 14, 2020.

  1. WoodSango
    Joined: May 2020
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    WoodSango Junior Member

    Thanks, you could very well be right. I just want to make my own carbon mast and prove the technique. If I fail, it’s only money...I’m pretty sure it’s a good build system for a diy guy.

    sglass waste? If I use 8mm foam The sglass helps with the thinner foam used
    Also, I’m using p60 instead of 80. I think the sglass helps there to.

    Sglass offers up 30-40% increase in structural benefit over eglass. My thinking (could be wrong) is use the 8mm foam instead of 10mm and spend the savings on a better skin
    Material?

    Any advice on this would be appreciated!
     
  2. WoodSango
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    WoodSango Junior Member

  3. Rumars
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    Rumars Senior Member

    For the rig, look what your designer said in the past. How to reduce costs for rig/sails (Sango from Woods) https://www.boatdesign.net/threads/how-to-reduce-costs-for-rig-sails-sango-from-woods.32760/#post-365237
    Composites are engineered to a specification and all components work together. This one was done for E-glass, that means E-glass is sufficient. Using something "stronger" like S-glass is a waste of money because the laminate will never see those loads where S-glass might be usefull. Or the core will fail before the skin. You want to use other fibers and core have the laminate reengineered for them. If the designer says P60 is OK then use it, otherwise not.
    On the subject of 8 vs 10mm core:
    1. Price. What is cheaper paying for 10mm core or for double the resin and glass?
    2. Do you plan to bang the boat much? If yes, choose the thicker skin.
     
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  4. WoodSango
    Joined: May 2020
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    WoodSango Junior Member


    Thanks, I re-read this advice From you and it seems solid.i have also read the link you furnished a few times also in the past.

    I’m going to go with the p80 8mm strucell (instead of p60)
    And 600 45 degree biax Eglass (Good quality glass)

    I got the point on cost of upping the foam size vs the price for heavier glass and more resin. But I want the heavier skins for cruising. Whew, took me awhile to get here, thanks for the help.
     
    Last edited: May 20, 2020
  5. fallguy
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    fallguy Senior Member

    The heavier skin for cruising is sort of nonsense. What are you expecting it will do?

    The foam and glass interface is not stronger with thicker glass. The hull panels are not stiffer with the 8mm core. I'd need to see testing to be sure. But the cube rule is in effect here. And by that standard; 8x8x8=512, and 10x10x10 is 1000, so the 10mm core is nearly twice as stiff sans glass.

    You are confused about things.

    Now, I am leaping, to be sure.

    The only way to know is testing, but I am fairly certain, based on mt knowledge and experience; the 10mm core is the best choice.

    Not to mention, I really love working with 400 gram glass. It will tops down wetout, where 600 will not. Both wetout better with some on the bottom; mind you.

    Anyhow, not sure why you would want an 8mm core over a 10mm core.
     
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  6. WoodSango
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    WoodSango Junior Member


    Weight savings was my attention. by using the p80 I figured the 8mm would be acceptable?

    So let me ask, I assume you would pick P80 10mm foam And the 400 eglass


    Thanks
     
    Last edited: May 21, 2020
  7. WoodSango
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    WoodSango Junior Member


    You are right, I just reconfirmed with an email I received from the designer..

    Options are
    8mm with 600
    10mm with 600
    10mm with 400 (light build)

    So my thinking was use 8mm p80 instead of p60
    Use 400 biax.

    which brings me right back to my original idea...

    Use the p80 8mm
    And use the sglass...

    I save weight
    I get a stiffer hull
    And the sglass has better protection then eglass...

    it’s a win win in my eyes..

    I’ll email the designer and put this all to rest. I’ll post his reply.
     
  8. WoodSango
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    WoodSango Junior Member

    I’m going to run a test any help will be appreciated..

    I’m going to do 3x1 ft test panels

    8mm strucell foam

    laminated with

    eglass
    Sglass
    Basalt
    Carbon

    Any suggestions on what we want to see with the test would be good and how I should run the test, before I start, would be a big help.

    I’m very interested in the basalt, I’m doing the others to compare that to.
     
  9. fallguy
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    fallguy Senior Member

    No. No. No.

    you did not listen

    10mm core is nearly twice as stiff as 8mm core per the cube rule

    personally, I would build it with 10mm and 400, but some people are not fans of 400 exterior for abrasion

    I would be very tempted to build 10mm (8 is foolish) with 400 inside and 400 outside with a 6 oz woven to just past DWL and perhaps up the dockside of each hull.
     
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  10. WoodSango
    Joined: May 2020
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    WoodSango Junior Member


    I understand what your saying.

    I’m agreeing with what has been said previously.

    I want to use the lighter skins, but with more strength then eglass...

    less foam equals less money in material
    Lighter glass uses less resin, more money saved
    The plans call for biax one layer per side
    10mm p60-600/400
    Or 8mm 600
    THE DESIGNER said I could use the p60 without problems
    With 600 or The light build is 400 (Not as rugged)

    I think I understand fully...

    I understand that I can use the 8mm and save some cost
    I understand I could use 450 basalt and achieve
    Less weight in skins
    The same hull strength as if I used sglass at half the cost per meter..Most importantly, I get a hull that’s around 50% better in all areas then if I used eglass. And what really makes me happy is the puncture resistance is like 100 times better then e or s glass..
    They took an elephant gun from 30 yards, and shot a basalt hull the bullets didn’t make it through the core...

    that’s my focus now, 8mm stru cell & 450 basalt. the basalt acts and laminates just like the eglass, matter of fact, I have read it is better with epoxy laninatiins then even eglass.
    Lays better, easy to wet out, ect..

    I get a much stronger hull, for about 3 bucks more a meter then good eglass....

    why wouldn’t u?
     
  11. fallguy
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    fallguy Senior Member

    I would not use 8mm over 10mm for the reasons I cited twice. 10mm is about twice as stiff and lighter with the 400 g layup. I would probably consider laying the woven over it because it finishes so nicely and would help in an abrasion event.

    If you shoot a gun at the hull; it will delam if it does not puncture, so the concept is silly. There is no foam capable of not shearing from projectiles hitting it at gun rates.

    I have no experience with basalt and have never seen it even.

    I would see if you can get some more advice from others. Rxcomposite is very wise on foam layups.

    I am just a Wood's builder using 12mm core and 22 oz triax.

    I have 6mm core here and it is really very flimsy. I can tell you without question, I would build your boat with 10mm core. It will be stiffer.
     
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  12. WoodSango
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    WoodSango Junior Member


    Prob better safe then sorry. I agree I’ll use the 10

    now it’s the skin weight
    400 or 600
    Basalt or eglass need to do more research on basalt


    Thanks
     
  13. fallguy
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    fallguy Senior Member

    As for the skin weight, 400 gram biaxial is a dream to work with. The only negative about it is it can be snaky, but so can 600. The way to deal with snaky fabrics is to dry lay them and use sharpie lines for references, not just side to side, but also for length. Suppose you are laying 8 meters of fabric and each meter stretches 50mm. At the end your fabric ends up narrow and long and under 400g/m^2, or worse, if you end up short...the length references really helped me on anything over 12' even if just to know pull more or pull less

    400 gram glass can be wetted tops down, although all biax wets easier if you wet the substrates first because the biaxial glass is basically two layers of fabric more or less...600 gram is nearly impossible to wet down through from a dry start..

    by adding a light layer of woven 4-6 oz; if you could do it the same time; you will reduce your resin rate in the 400g and probably need very little to wetout...and end up with a better laminate; easier to finish with more abrasion resistance..obviously an abrasion layer is useless on the inside of the hull; so an abrasion layer is dockside and bottom only

    And despite me saying 12oz will wet top down; don't try it on your hulls; it is too time consuming; you need to wet the sibstrate and roll off the glass for long pieces.

    Have you laminated foam before?

    I have a couple other tips if you have not done it.
     
  14. WoodSango
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    WoodSango Junior Member

    Thanks again, not Much experience with foam core. Most of my limited experience is infusion and prepreg.


    I’m going to continue to research that basalt, it comes in a 450.Might just be perfect!

    Everything I have read, Basalt handles about like eglass, a few have said it wets out even easier.

    At this point, unless Mr woods tells me I’m nuts, it’s

    10mm strucell p80
    Basalt 450, that stuff is so rugged, I doubt
    I need any other protection.
     

  15. fallguy
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    fallguy Senior Member

    Where can you source basalt?

    does it match up well with the resin and core for elongation and cte?
     
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