spray foam or pour foam ?

Discussion in 'Boat Repair Help' started by TCAT, Jan 9, 2008.

  1. TCAT

    TCAT New Member

    Messages:
    25
    State:
    mo
    i am currently redoing a boat and need to know which polyfoam would be the best way to go . would the the sray kind be better or the pour kind ? which density would be best 2# or 4# also needing to shorten steer cable can u have them cut down or do u have to buy a new one that is right lenght?
     
  2. spoonfish

    spoonfish New Member

    Messages:
    3,780
    State:
    Warsaw, Mo.
    Welcome to the BOC Tom.
    I used the 2# pour in on mine and it worked really well. I dont know a lot about all the differences but Mark J. on here will be able to help you decide what will work the best and why. If he see's this thread Im sure he will reply or send him a pm.
    Im sure you will get several replys to help. Good luck with the boat and again Welcome aboard...
     

  3. BKS72

    BKS72 New Member

    Messages:
    3,361
    State:
    East of KC
    Used pour foam from this site on my boat just a couple of weeks ago. http://www.jgreer.com/Foam Page.htm Good stuff and great prices. I PM'ed Mark J about it before I bought it (he's forgotten more about boats than I'll probably ever know) and I think he said their foam looked OK, but was iffy on their epoxy.

    As far as the steering cable, I picked up a 14' cable, helm, and steering wheel that are as good as new for $56, including shipping. There were tons of them on there, probably can find one there and it would be less hassle than cutting one down. Good Luck!

    Branden
     
  4. BKS72

    BKS72 New Member

    Messages:
    3,361
    State:
    East of KC
    Sorry, forgot to say I got the cable and stuff from Ebay on the earlier post.
     
  5. JERMSQUIRM

    JERMSQUIRM New Member

    Messages:
    13,145
    State:
    il-waynesv
    ya ide go with the two part pour type.
     
  6. Mark J

    Mark J New Member

    Messages:
    9,407
    State:
    Four Oaks, NC
    You've been told right. Two part CLOSED CELL flotation foam.
    The stuff in a can is insulating foam and open cell. Not good for nothing in a boat.

    A word of advice. Make small pours. You dont have to pour it all in one lick.
    This stuff will literally blow a boat apart at the seams. Even welded seams.
    No kidding. If its expanding and has no where to expand to something has to give and it wont be the foam.

    2 pound is adequate enough. The higher pound densities come in handy in some situations where the foam is actually used in a supportive manner like for some types of flooring.

    A foamless option is permanantly sealed compartments.
    Air is lighter then foam.
    Its a popular belief that foam makes a boat float higher in the water.
    Its the opposite. Foam adds weight.
     
  7. BKS72

    BKS72 New Member

    Messages:
    3,361
    State:
    East of KC
    When you do go to pour, get your calculator out. I did the math and figured out the volume of the void I wanted to fill - in my case 3" x 14" x 60" for 2520 cubic inches or just less than 1.5 cubic feet.

    The foam I used made 4 cubic feet per gallon, or 1 cubic foot per quart. I mixed batches of a little more than a pint of A and a pint of B for maybe a quart and a half of pre-expanded foam. When expanded, it came out about right. This isn't foolproof because ambient temperature, temperature of the boat, and liquid foam temp will greatly affect the amount of expansion (warmer = more foam, colder = less foam) but it will give you an idea of how much to mix.

    If your pour makes more foam than expected, you can cut off the excess and put the pieces in your next void and pour over it. Also, if you need to smooth off your pour, a sanding disc on a 4" grinder worked well for me. Overall it's pretty fun to work with, but I'd recommend latex gloves - once that stuff is on you it pretty much has to wear off :wink: Good Luck!

    Branden
     
  8. Big Dav

    Big Dav New Member

    Messages:
    1,016
    State:
    Southwest
    When I re built my Tracker a few years ago I used Dow Froth Paks. It is a spray in insulating foam but it is closed cell and can be used for flotation. I contacted them before I used it and I also tested it for myself before it went into my boat. I had to replace the floor foam and the foam under the front deck.
    Here is a link to the product I used. http://www.dow.com/buildingproducts/frothpak/
    You can follow that link and go to the FAQ section and it tells that is can be used for flotation and it is closed cell foam.
    Cost me about $200 to replace the foam but the price may have gone up since then. Man that was a lot of work. At the time that was the best option I could find. If I were doing it again today I would use the pour in foam. If I could not get to an area to pour in the foam I would use the Froth Pak again.
    The Dow Froth Pak 180 kit yielded 16.6 cubic feet and has a density of 1.75. Like I said there probably was better options at the time, I just did not know about them. I think the guys have you pointed in the right direction if you can access the area to pour in the foam.

    FYI, Great Stuff spray foam by DOW is a closed cell foam.

    Thanks
    David
     
  9. Big Dav

    Big Dav New Member

    Messages:
    1,016
    State:
    Southwest
    Darn 5 min edit timer.:angry:
    Like I was saying the Great Stuff foam is closed cell but I am not suggestion it for use. That is what I was told by Dow when i contacted them about the Froth Pak. i just checked there web site and it does say it is closed cell but does not give the density. I have used it before to fill in weak spots under the floor of boats. I have never had a problem with it but the pour in flotation foam may have been a better option if I could have accessed the areas to pour it. I "fixed" a weak spot in a guys jon boat that could not be accessed to pour foam in and I used about six taped together straws on the can to reach the spot. I just added a little at a time and it fixed the spot. I have a couple of places on my new boat that I may fix the same way. I cannot get to them to pour.:big_smile:

    I hope this helps.
    Thanks
    David
     
  10. CarolinaCats

    CarolinaCats New Member

    Messages:
    223
    State:
    Rural Hall
    I use 2 part foam in Taxidermy almost daily building specialty forms and habitat scenes. I purchase mine from, US Composites http://www.uscomposites.com its the cheapest priced 2 part foam I have been able to find. I think its 59 bucks for the 2 gallon kit. To get the most expansion from the foam use it in a well heated area or in the heat of the summer. Winter time and cold work areas , you get less expansion results. If you need to slow down the expansion take a squirt bottle and spray water on it as it expands. That will slow it down some. DO NOT pour the foam and seal it off! Leave the pour hole open for it to expand any extra to prevent busting seams like Mark said.

    <quick story>
    Several years ago A contractor supervisor forgot to "insulate" a (fiberglass) bath tub for a retired couples new retirement home. So he went in the access door in the closet and sprayed about 5 cans of the spray insulation stuff. Well end result, He got fired, the complete tub/shower encloser was replaced. The bathtub bottom/floor buckled so bad there was a gallon of water standing in the tub! It worked its way up the sides as well. What a freaking mess!