1979 246 CCP stringer foam

[gman 82 aquasport]

Back to the original ?
The new foam is closed cell, as long as it's not molested it will stay that way a long time, if you have to cut it you will need to seal it somehow(epoxy).
As far as strength, I pulled the following info from uscomposites website on expandable polyerethane foam,
For comparison                
                                                     2lb foam                vs                   4 lb foam
Buoyancy    per cubic foot                 60 lb                    vs                     58lb
Parallel compression strength                40psi                  vs                       90psi
Tensile strength                                30psi                   vs                      110psi
Shear strength                                    30psi                   vs                       70psi
Flexural strength                                  50psi                   vs                     120psi

They post that after years of water contact the foam can lose it's closed cell behaviors and hold water..It's mainly in case of pinholes and in case of striking submerged objects to keep the boat afloat longer
Hope this helps your decision on foam or no foam

[dbiscayne]

If you wanna figure out how much foam you'll need to float the boat don't just compare the boats weight to the amount of bouyancy provided by the foam.
Gotta factor in the specific gravity of each different item on the boat, including people, and toss in a safety factor.  You'll find you actually need less foam than what you previously mentioned.
Basically accounting for the fact that 100lbs of wood doesn't need as much foam to float as 100lbs of steel  
http://www.glen-l.com/weblettr/weblette ... ation.html
or
http://www.uscgboating.org/regulations/ ... rt1_e.aspx

[orb]

I used 2lb foam in the stringers in my 240. The 2lb  2 part poly foam is miles and miles above the original foam in the stringers. I figured that the 2lb foam is stronger than what was there originally, so I would just use that. The foam strengthens the whole stringer system. I would check and make sure that the stringers have not come aloose from the hull anywhere. The stringers in my 240 busted loose in front of the console.

[kaptainkoz]

Gman thanks for the awesome stats I appreciate them. Seems like the different strengths make the 4lb a better choice if maximizing structure is a consideration.
DBiscayne, thats something I thought of as well that certain materials have some bouyancy. Obviously plywood floats. I figured that by reasonably filling all the empty cavities under the floor I would more than cover positive bouyancy. I hope to never find out!!!
Orb, yes, stringer integrity is high on my inspection list and if all seems well it may get an additional fillet just for good measure.

Thank you all again for sharing exceptional information.

[kaptainkoz]

So interesting turn of events today. As a Realtor not far from Sanday-Ravaged areas, I was in Wantagh NY today and began noticing pieces of blue floatation foam that is typically used for floating docks, spread out along the edges of the waterways that feed the bays. I drove to a bay front park and started to hike off towards the water and found a decent amout of foam in the marsh. Not a bad collection for wearing slacks and dressy shoes. I plan to go back with proper gear and spend more time looking for larger pieces. Im sure I will find all that I need to fill hull voids to provide positive floatation and do the shore line a service with a little litter removal. Win win!!!!

I can clean the pieces up and cut them to a proper shape, then hold them in place with a few dabs of 5200 so they dont rattle and thump while pounding chop. The idea is so any water that gets in there will easily run down and into the bilge. I am convinced that I do not want to pour 2 part foam into open cavities because of how tightly it seals against the bilge. Id rather have loose fitting pieces that will allow run off.
 
I priced the stuff out on the internet and a DOW brand 10 inch by 20 inch by 8 foot piece was $144 before shipping minimum 8 pieces. I dont exactly want to spend $900 on something I can find for free, especially on as tight of a budget as I am on now. Times are tough!!!!

[CLM65]

Good deal!  You are filling a need for your rebuild and cleaning up the environment at the same time!  I used those blue foam blocks when I built my floating dock about 12 years ago.  Still floating, although maybe not as much as they originally did.  And that is with 24/7 submergence in water.  I think they will be fine for your boat.

[gman 82 aquasport]

Recycling is not a dirty word I would use that stuff in a heartbeat

[kaptainkoz]

Went back into the bays today for more foam. Luckily I think I have enough now. Man i tell ya, nothing in life is free! Hauling this stuff out 300 yards of thick over growth and brush almost had me reaching for the credit card. "This sucks" came to mind quite a few times. But hey, free is free and I felt good about doing a good service to the bays and I worked up a sweat. Below is a pic of the what i saw. Now I would love to say I pick up every piece but I didnt. I grabbed what was larger and what seemed to be newer. The older stuff was more porous. I was selective which means I had to leave alot of what you see behind, but quite a bit came home with me.




Here is everything that came home with me. This is in addtion to what I brought home the other day


I should have more than enough now. There are additional pieces under the trailer behind the stacks. I figure about 1/4 will go to waste as I cut and trim it clean.

[Double Trouble]

Double Trouble,
I fish out of Jones inlet and not the Great South Bay. Its a bit east of me. I kind of missed the boat on the fall striper run from not having a functional boat as I am at the start of this renovation. Also, what made it worse was Sandy hit just right and ruined the fall run for us. I got in two trips before sandy and brought a keeper home. The spring run was pretty good. There were ALOT of big fish that came over the rails which is historically bad for the species. Apparently this pattern happened before and it is a bad sign that there arent as much young around to keep the numbers high. I hope they are wrong but history repeats itself.  How about you? Have any good striper days?

I had excellant days in the spring run chunking in Jamaica Bay into early June. Sept saw some good days off the rockaways livelining bunker. The bunker schools were all over some days and no where to be found on other days.