What to use under stringers

Discussion in 'Materials' started by 95 outlaw, Jul 17, 2007.

  1. grady
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    grady Novice

  2. the1much
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    the1much hippie dreams

    they should of used hull-n-deck,,,or,,,they kicked off their glass to hot,,,i've never seen it do that ca-ca before,,,but then again,, how old is that boat,,,heheee ;)
     
  3. grady
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    grady Novice

    Old

    it's a 86' grady white
     
  4. the1much
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    the1much hippie dreams

    wow,,,ya,,they should have used hull-n-deck,,so the "too hot" batch thingy is probably what happened.
    or for some odd reason ya had ALOT of stress on em.
     
  5. ratrace2
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    ratrace2 Senior Member

    I got a question: if divinycell, coremat, etc foam in a stringer has no structural purpose. then (1) why use such an expensive material $125 fro a 4x8 sheet. (2) why not just make them hollow....
     
  6. the1much
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    the1much hippie dreams

    rigidity,,,,,take a soda can ( empty) and squeeze it,,,petty easy huh,,,,now take that empty can and fill it with sand, and close the top.,,,,now try squeezing it.
    its real hard.
     
  7. grady
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    grady Novice

    Boring

    Hey Much, Here's what happened (at the risk putting everyone to sleep) . From what I can gather the engine compartment was laid up with chopped strand and I guess if it's not wetted out properly it can be fairly weak.

    It was originally powered with a 230 hp OMC (305 ci gm sm blk), when I repowered with a 280 hp 350 ci sm blk, I think all the weak areas were over stressed. And cracks formed at all the corners.In these pics you can see how dry the glass appears (starved of resin)http://www.boatdesign.net/forums/showthread.php?t=17029

    And with the new power plant rated at 320 hp, I thought it best to repair these areas. But after much debate I decided the best coarse of action was to grind all of the chopped crap off. While grinding i would come across pockets of water, and wet wood, although I found no rot the only way to fix right was to remove everything and replace with new beefer stringers and engine bearers. ( and not to lag down into the tops of the bearers for the engine mounts.)

    Anyone awake?

    After grinding the glass off the tops and sides, I found this funny little void under the stringer. ( most of the filler, grout whatever was missing) the stuff under the bearers was pretty much intact.http://www.boatdesign.net/forums/showthread.php?t=17029&page=2

    night night everyone
     
  8. the1much
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    the1much hippie dreams

    ya man,,,thats why (AND I DONT CARE WHO THE STUPID-*** MAKER IS) i dont believe in chop guns,,,they should be outlawed,,(and yes i know theres people out there that use the idiotic things,,and everything is fine) 1 reason is it makes LAZY lay-up people,,,and ya can pay any idiot $2.00 an hour to run 1.,,,where hand lay up,,,,your there touching it all the way,,ya have MANY eyes looking at it during the "work" time,,,ya pay MORE attention to air pockets,,,o,,,YA CAN SEE AIR POCKETS or DRY areas easier.and then theres the idiots that think chop is stronger ,,,,jus cause it goes in every direction (which if they thought about it,,,it ACTUALLY makes it weaker,,hehe),,,well,,,,,this should of gone in the "grumpy ravers" thread i guess,,,,,pay-back fer the snoring hehe ;)
     
  9. dragonjbynight
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    dragonjbynight Senior Member

    wouldn't that theory be the same with particle board and plywood Jim..with chop being equivalent to particle and cloth to plywood? seems if that holds true, cloth is the stronger of the two.

    my opinion anyways
     
  10. the1much
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    the1much hippie dreams

    yups,,,,cloth will always be stronger,,,till ya talk bout mat,,,then thats jus flat chop hehe ;)
     
  11. the1much
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    the1much hippie dreams

    "had a brain Fart" ,,,think of it this way,,,,(these numbers are just for EASY thinkin),,in a 50' boat made of chop,,in a 1" strip, from stern ta bow,,you'll have 5000 pieces of glass stuck together by resin,,,so that strip is actually only as strong as the resin gluing them together,,,,,with cloth youll have say 2500 strands (continuous strands weaved together like ya cloths) ,,now them are strands weaved together,,,but in 4' pieces at a time,,so you'll actually have like 50 connections. and in them sections even without resin,,try pulling it apart,,,,,,,,,,,,,,so,,would ya rather have 5000 connections,,or 50?
     
  12. ratrace2
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    ratrace2 Senior Member

    Protect that new stringer job

    Hey "1Much,"
    Wouldn't it be a good idea to "coat" the inside bottom of the boat below the water line with epoxy, especially the "always wet" areas?
     
  13. the1much
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    the1much hippie dreams

    dont know,,,i hate epoxy,,,(not really,,,just dont use it unless i have to).,,then ya got to think about painting it if ya want a "finished" look...but the paint i use in them areas is better then epoxy any day hehe ;)
    and with a "coat" of straight epoxy,,,i dont know how paint would stick,,,or hold up to "chipping",,,,just like trying to paint a coat of poly or vinyl,,,does work,,,but not for long.
     
  14. ratrace2
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    ratrace2 Senior Member

    Ya could gel-coat over the epoxy. It's just that epoxy has such great water resistant properties...No osmosis, ya know.
    I starting to think that most of this stringer "rot" is coming from water laying inside of the boat.
     

  15. the1much
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    the1much hippie dreams

    even if the water stays there,,,if you put the stringers in right,,and ya painted it,,,there is no way water can get in,,,each stringer should be like its "own little boat",,and NO water should get into ya "boat"(stringer)
     
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