foam enhancement

[1966starcraft18ft]

Hey guys. well, I have a technical question for you all. I have my boat at work and have been working on it on my lunches. I am almost ready to install floor for last time and fasten it down with rivets. My boss has been conversing with me about how it has been coming along and he had made the comment about the amount of foam there is in it. Right now, the middle of the stringers( front to back) is packed with that bead type foam in it. There is no other foam on the boat. Do I need to ad more anywhere? We did the math and right now I have 12 cubic feet of foam now and our math showed that it needs 25 cubic feet. we used 1550 for the weight.

What do you guys suggest? cant afford it to get to a stand still. Has to be ready by memorial day weekend. said it would be to the family. I live in Minnesota and would not be out in cruddy weather hardly ever.

 

[barato2]

Re: foam enhanncement

Re: foam enhanncement

would not be out in cruddy weather hardly ever.

FORGET SUCH SILLY THINKING....kinda like not getting your kids vaccinated cuz they haven't had much polio around these parts lately. you cannot predict what sort of conditions you (and future owners of the boat) will run into, and making your basic safety item plans based on an unrealistic analysis and excessive need to rush the job along is not a good idea. would you rather answer Qs about why you didn't quite have the boat ready by M-Day, or about why your family drowned due to YOU being in too much of a hurry to install sufficient flotation? they didn't expect trouble on the Korean ferry either...... someone on here will probably know where to find a link to that story where the brand-new 2011 model boat went down on Lk Michigan while being tested by Grt Lakes Angler in good weather......the author was only around to write the story due to grabbing a Coleman cooler, and because the water was warm enough that hypothermia didn't get him. how warm is the water where you boat? would you be able to survive 5 hours in that water before dying from hypothermia? have i got your attention yet? sorry to sound harsh, but you don't want to cut corners on safety.

fill the entire area under the decks with foam, as much as you can stuff in (while leaving a drainage channel down in the center of bolge). fill the area under gunwales and splashwell, and under bow cover if you have closed bow boat. the stuff you're using thus far will eventually absorb water and rodents like to make nests in it, but it will work. i'd suggest using extruded foam for the remainder.

again, sorry if i sound like a jerk, but we'd like you, your family, and your laboriously restored boat to be around for a while. kudos to your boss for thinking about you.

 

[1966starcraft18ft]

Re: foam enhanncement

Re: foam enhanncement

ok. ok. I get the point. he only thought bout it cuz of people he knew that took foam out to make storage space and it literally bit them in the butt. I was asking in hopes getting hard info from guys who have done foam replacement and to see if our calculations sounded right. only said the timeline so that someone didn't sit on the answer for a time. I had every intention doing it right and if it aint ready by then, they will live.

The blue or pink better for this type of application? what about spray foam? that ok to use?

Does the 25 cubic ft sound right?

 

[barato2]

Re: foam enhanncement

Re: foam enhanncement

wow, did i really say all that? dang, that guy is a prick. sorry again.

your boss is 100% right. not sure about the calculations or the # of cubic feet. i just work on the "stuff as much as you possibly can in, wherever you can" plan. extruded foam comes in both blue and pink, i think the only difference is the brand (Dow vs Owens corning?). either works fine....i have some of each and they seem identical.

spray foam is a dangerous swamp for discussion. yes, it will float the boat if it's CLOSED CELL (open cell absorbs water, assume it's not closed cell unless it says so) and it fits into odd spaces easily. BUT....it makes a mess; will be durn near impossible to remove if you, say, hit a floating log and dent the hull badly; and will be durn near impossible to remove if you want to remove it for any reason. i've seen suggestions of using saran wrap or cooking spray oil to coat the area to be foamed so it comes out easier, but have not tested either.

 

[ezmobee]

Re: foam enhanncement

Re: foam enhanncement

The blue or pink better for this type of application? what about spray foam? that ok to use?

Pink, blue, or even Lowe's house brand green is all the same stuff. Extruded polystyrene. NOT Expanded polystyrene.

Putting foam behind the side panels is a great idea I wish I'd had when I did mine.

The idea here is that if swamped your boat does this:



as opposed to sinking to the bottom like a rock. I'd rather have something to hold onto waiting for help to arrive than treadin' water.

 

[Gibbles]

Re: foam enhancement

^ what they said

Stuff it anywhere and everywhere you can (leaving room for the storage ect).

I stuffed foam everywhere I could, even behind the side panels, and I'm still thinking of areas to stuff more :lol:

 

[Gibbles]

Re: foam enhanncement

Re: foam enhanncement

Oh yeah, we forgot to put the plug in my FIL's boat one day, rushing to get out on the lake...

That foam helps slow the sink... we made it back to the ramp just in time for it to settle on the ramp... from there we got the plug and started bailing, once it started floating again back on the trailer for some drain time...

Tinny with little to no foam, I bet it would of sunk like a rock...

On that note, my Jetstar did not have much space for foam, it still worries me...

 

[Grandad]

Re: foam enhanncement

Re: foam enhanncement

I figured 35 cu ft for my 21' Holiday, so your figure of 25 is probably pretty close. I tended to gross up the calculation where dubious. I figure that sinking slowly with almost enough flotation isn't a lot better than sinking without flotation. To be entirely truthful, the parts of your boat that are somewhat heavier than water are a lot heavier than air. Accurately calculated, you'd need to calculate the boat's weight when submerged by comparing the specific gravity of aluminum and iron with the specific gravity of water. I'd rather overbuild flotation. See my flotation attempt here and further in the same thread. - Grandad
http://forums.iboats.com/boat-resto...iday-reno-hull-repair-517895.html#post3500536

 

[jigngrub]

Re: foam enhancement

With the right amount and proper placement of floatation foam your boat could float like this:
https://www.youtube.com/watch?v=M30nDtZ4iys
... and you and your passengers won't even hardly have to get your feet wet instead of just having something to cling onto for life.

... and yes, your calculations of 25 cu. ft. are correct. 1550 divided by 60=25.83

5 sheets of 4'x8'x2" thick foam will yield 26.56 cubic feet for 1593.6 lbs. of floatation.

Remove that white beaded crapola and replace it with the modern polystyrene sheet foam.

 

[1966starcraft18ft]

Re: foam enhancement

Hey guys, so, after my last post, my boss did some brainstorming about my foam snaffoo and has come up with a two fold resolution to the lack of foam in my boat. He found at bed bath & beyond, a 25lb bag of bean bag filler. Same stuff they make Styrofoam out of. put that in replacement bags for a parents dream, diaper genie, and ziptie the ends. and tada, air pockets that also have foam in it. According to his figuring, that 25 lb bag will take care of my other 13 cubic feet of foam I need to install. doing this on a budget so will be reusing the foam that is already in there.

I will still be buying a couple of sheets of the foam insulation for behind the side panels and under the gunwhales.

 

[Grandad]

Re: foam enhancement

As I recall, bean bag filler is white styrofoam pellets. You don't ever want them to escape the bag or you'll have a snowstorm in your bilge that likes to clog things like drainage passageways and bilge pumps. So you'll have to use some pretty tough vinyl bags that will conform to the cavities, yet won't get cut on anything. Also, if water ever enters a bag, the pellets will absorb water after a while and weigh down your boat. - Grandad

 

[ezmobee]

Re: foam enhancement

Your proposed solution, while economical, sounds like a future nightmare. Noodles would be an improvement over that.

 

[barato2]

Re: foam enhancement

and rodent nests....don't forget our little furry friends, they'll love that bean bag chair filler.

i understand budget. re-use your expanded foam for up under gunwales, splashwell, behind side panels, under bow....the places that you can get at to replace it if needed, and where if you have standing water, you have bigger, more immediate issues than long term water absorption by foam. then use the extruded stuff for under the deck

 

[jbcurt00]

Re: foam enhancement

penny wise, pound foolish..........

Budget driven rebuilds are often more time consuming & difficult to complete when the bottom line is very thin and money can't be spent unwisely. But budget builds can be done, and done smartly.

I'd NEVER skip flotation foam on a rebuild, and I'd go w/out foam before I'd give false security of adequate flotation via plastic bags, filled w/ loose styro beads. At least w/ no flotation foam, when my boat sinks, I also won't be fined for all the loose styro beads floating everywhere..... But again, I'd NEVER skip the flotation foam, ever.

Safety should always outweigh budget constraints. It's not just whether or not you are a safe boater, only boat in good weather or are an exceptionally attentive captain. Carp happens, and on the water, it happens quickly.

 

[theoldwizard1]

Re: foam enhanncement

Re: foam enhanncement

fill the entire area under the decks with foam, as much as you can stuff in (while leaving a drainage channel down in the center of bilge).

This is the problem with the pourable, self-expanding foam ! It works too well in filling all voids and does not allow water to drain down the center of the boat to the bilge pump. You also need what are call "limber holes" in any ribs or stringers so that water can also drain to the lowest part (center) of the boat.

Fill the area under gunwales and splashwell, and under bow cover if you have closed bow boat.

Installing floatation up under the gunwales and above the floor in the splash well will help keep the boat upright and "turn turtle" (roll over) if you do have a major hull breach.

 

[jigngrub]

Re: foam enhancement

penny wise, pound foolish..........

Budget driven rebuilds are often more time consuming & difficult to complete when the bottom line is very thin and money can't be spent unwisely. But budget builds can be done, and done smartly.

I'd NEVER skip flotation foam on a rebuild, and I'd go w/out foam before I'd give false security of adequate flotation via plastic bags, filled w/ loose styro beads. At least w/ no flotation foam, when my boat sinks, I also won't be fined for all the loose styro beads floating everywhere..... But again, I'd NEVER skip the flotation foam, ever.

Safety should always outweigh budget constraints. It's not just whether or not you are a safe boater, only boat in good weather or are an exceptionally attentive captain. Carp happens, and on the water, it happens quickly.

I couldn't agree more, floatation foam would be the very last thing I'd skimp on too. You can't put a price on a human life when you really need the floatation foam.


It never ceases to amaze me how people don't have the money to build their boat right... but when it comes to filling the boat up with gas and running it around on the water all summer, money is no object.:facepalm: