Fill hull with foam?

Discussion in 'Fiberglass and Composite Boat Building' started by wrbowcal, Apr 3, 2010.

  1. mark775

    mark775 Guest

    There was a crazy, and soon, fat, lady here that tried to drink enuf Dr. Pepper to float a seventy foot scow on a high tide. For such an endeavor, I highly recommend buying said bottles and not drinking their contents... as this lady had to give up her dream when falling from the boat becaue of the ladder she broke!
     
  2. Ike
    Joined: Apr 2006
    Posts: 2,677
    Likes: 477, Points: 83, Legacy Rep: 1669
    Location: Washington

    Ike Senior Member

    I beg to differ. The USCG doesn't give a damn if you use plastic bottles. That is an urban myth invented by the foam industry. The flotation regulation does not specify what you use. It is a performance standard not a specification. I spent many years at USCG Office of Boating Safety running the program with the test lab to test boats for flotation. Most boat manufacturers use foam because it is convenient and fits well in the production process. (and they think their customers would think that plastic bottles were unprofessional. I know because i suggested it)

    However the most clever one I saw used plastic milk bottles. Unfortunately it failed because the bottles had metal caps which corroded. Enough water got into the bottles to make it fail the flotation test. Plastic bottles with plastic caps would work just fine.

    Besides, this is a 27 foot boat, the USCG regulation doesn't even apply to it (monohull boats under twenty feet must have flotation)

    Styrofoam would work fine except for one thing. Styrofoam dissolves when in contact with gasoline and other petroleum products, and many types of cleaners used on boats. To prevent this styrofoam in the bilge would have to be encapsulated in glass/epoxy or bagged in a plastic bag and sealed. But, I use styrofoam in my 12 foot dink and it works just fine.

    PU has had problems absorbing water, but only the two part pour or spray foams. I worked on a research project to find out why but it went no where. The manufactured block PU foam does not have this problem. Also some ( a few)manufacturers use Polyethylene foam.the type you see in pool noodles. It works great too but is simply hard to get.

    PS: unless of course you buy pool noodles which is exactly what one manufacturer used.
     
    1 person likes this.
  3. tinhorn
    Joined: Jan 2008
    Posts: 575
    Likes: 20, Points: 18, Legacy Rep: 310
    Location: Massachusetts South Shore.

    tinhorn Senior Member

    I'm leary of milk jugs--seems they'd collapse under just a bit of pressure. I'm not even going to use the 2-liter soda pop bottles for the same reason. I'm sticking to the itty-bitty pop bottles because they seem rigid enough to hold up if they were immersed.

    Pool noodles are a clever idea. You can find those at dollar stores for a buck apiece. (They cut like butter with electric carving knives. I use 'em for dinghy fenders.)
     
  4. rasorinc
    Joined: Nov 2007
    Posts: 1,853
    Likes: 71, Points: 48, Legacy Rep: 896
    Location: OREGON

    rasorinc Senior Member

    I was talking about dock billits made of stryofoam--closed cell--does not absorb water. I've got them floating a dock now for 30 years and still fine.
     
  5. rasorinc
    Joined: Nov 2007
    Posts: 1,853
    Likes: 71, Points: 48, Legacy Rep: 896
    Location: OREGON

    rasorinc Senior Member

    I was talking about dock billits made of stryofoam--closed cell--does not absorb water. I've got them floating a dock now for 30 years and still fine.
    this type of stuff http://www.larkdock.com/styrofloat.htm
     

  6. Ike
    Joined: Apr 2006
    Posts: 2,677
    Likes: 477, Points: 83, Legacy Rep: 1669
    Location: Washington

    Ike Senior Member

    How about ping pong balls? One boat builder did. Another built a boat out of beer cans. He wrapped them in glass and epoxy, making essentially long pool noodles and use them to form the hull. I suppose he enjoyed emptiing the cans too.
     
Loading...
Similar Threads
  1. reelpleasure
    Replies:
    5
    Views:
    3,843
  2. BernieJ
    Replies:
    13
    Views:
    1,279
  3. massandspace
    Replies:
    20
    Views:
    1,891
  4. IdahoBoats
    Replies:
    6
    Views:
    1,460
  5. Jason Rodgers
    Replies:
    9
    Views:
    1,501
  6. DogCavalry
    Replies:
    26
    Views:
    2,835
  7. Heynow999
    Replies:
    8
    Views:
    2,683
  8. garage monster
    Replies:
    9
    Views:
    3,430
  9. L'eau.Life
    Replies:
    4
    Views:
    2,471
  10. midcap
    Replies:
    10
    Views:
    6,365
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.