Re: Formula 330SS Bulkhead Replacement
Every person has a opinion... having been there done that here's one. Calculate the area and figure out the expansion rate that should give you the volume you need. Heat the surruonding surfaces to 80 degree's a hair dryer or heat gun will do well. Do one controlled massive mix and pour and fill the tank with water to prevent deformation. I if i remember correctly you have 15 minutes mix time it does not explode once poured
One massive pour will allow the foam in a liquid state to settle..the proper heat will allow it to expand at the rate it was intended to...make sure of your volume and allow for expansion escape..Then stand back and watch it expand form your vent's...going that way with 9lb foam i have a floor that feel's like its concrete.
Actually more like 15-30
seconds of mixing time, then it starts to expand. Expanding lasts for about 5 minutes.
Here is the info from the US Composites web site. . .
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[SIZE=+1]Urethane Pour Foam Overview[/SIZE]
- [SIZE=-1]This two-part liquid, expanding rigid urethane foam is a closed cell, pourable foam, which will resist the absorption of water.[/SIZE]
- [SIZE=-1]The densities shown refer to the weight per cubic foot of expanded foam (12" x 12" x 12").[/SIZE]
- [SIZE=-1]Once fully cured this foam can be laminated over with any type of polyester, epoxy or vinyl ester resin without melting.[/SIZE]
- [SIZE=-1]This product can be poured in multiple layers with excellent bonding between layers. [/SIZE]
- [SIZE=-1]All expansion rates and times given are temperature critical. Temperatures below 75 degrees F will lower the expansion rate therefore requiring more foam. Ideal working temperature is 75 to 80 degrees F or above.[/SIZE]
- [SIZE=-1]Accurate measuring of these products is extremely critical.[/SIZE]
- [SIZE=-1]Working time before foaming: approx. 45 seconds[/SIZE]
- [SIZE=-1]Time before full expansion: approx. 5 minutes[/SIZE]
- [SIZE=-1]The lightweight foam is commonly used for filling voids, filling under decks and practically any other flotation or insulation application. Higher densities are used for architectural castings, support applications and has virtually an unlimited number of potential uses.[/SIZE]
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Basically, the chemical reaction starts quickly and lasts for about 5 minutes. Higher temps yield higher expansion. . . not sure how much expansion you loose as the temps are lower. I am using the 4 lb/cubic foot density variety and I have a 20 cubic foot kit. I have calculated the volume to surround the bottom and sides of the tank to be approx. 12 cubic feet and the volume needed to fill the storage compartment floor around 1.5 (1-1/2) cubic feet.
I am guesstimating that the reduced temperatures may yield about 80-90% of the spec'd expansion rate, so, my 20 Cu. ft. kit may yield only 17 +/- cubic feet of foam . . . Still enough and should have some extra in case any particular area comes up shy, I can do a second pour. As long as it expands partially up along the sides of the tank, I am good for a second pour.
I am contemplating whether to pre-heat the liquid or to heat the areas in the boat (or both) so that the temps involved come closer to the spec'd range. On Cape Cod, we probably won't see 70-75 degree F temps until mid-June
EDIT - actually, I just found some additional info in the FAQ's on the expansion rate of the foam as the temps are lower . . .
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[SIZE=-1][SIZE=-1]9. Can I use the foam outdoors?[/SIZE][/SIZE]
[SIZE=-1][SIZE=-1]Yes. Our expansion rate of the foam is based on temperatures of 80 degrees F at moderate humidity. When using this foam in temperatures below 80 F you will see a reduction in expansion. At 50 degrees F you would probably only get half the normal expansion. For using the product during winter months it is ideal to work in a heated garage/shop in which you can get the product temperature and air temperature up to about 80 F.[/SIZE][/SIZE]
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So, maybe I would be best to heat everything up a bit . . .
