Flotation Foam

[fireman24mn]

Good story Jerry, the only thing I would add concerning a bilge pump is that it is only the best money you can spend if it has an automatic float switch.

I agree with the automatic bilge. It lets you know right away if there is a water problem. Say you forget the plug , driving and plug falls out, you tear open the bottom, frost plug comes out of engine, hose fails, ETC. You don't need to wait until you see water coming over the floor before you know there is a problem. Once the engine well is full of water and it starts showing on the floor the lower pulley is submerged in water and flinging water everywhere in the engine compartment potentailly killing the engine. Then you are stranded and if you cant make it to shore better get the life jackets or hope there is enough foam to float your boat.

I have went back and forth on foam on the 23 and i am thinking I will foam for the strength and sound quality it will provide, but I am thinking that I will leave some kind of gap so that water/ air can pass threw and into the bilge. I have been trying to figure out a plan to do it. Couple ideas I have came up with would be a tube or PVC of some sort laid in while foaming then pull it out leaving a void for air/ water kind of like a drain tile. Another option I thought of would be a balloon like they make animals out of. They are long and skinny then I could just pop the balloon and would have a void. Last I have seen where people put "liner" or something in the cavity, pour in foam then cover it and let it dry. Then remove the liner and you have a foam block the exact size of the cavity you then could shape or cut out what ever you want. I don't think this method would add as much strength though as it would not be bonded to anything just floating around in the cavity but i suppose you could glue it back in once you shaped to how you wanted to.

[Jerry]

Just my thoughts; These boats lasted 40-50-60 years with a foam that would hold water. The foam Red uses won't hold water, so don't leave any room for water to collect, FILL IT UP.  We won't be leaving them outside to fill with water, and if by some chance 40 years from now there is some wood rot. It won't be my problem

[Plugcheck]

     Is the foam from Express Compossites the type that does not hold water?   Curious to know if the product Red uses is the same, and if not, where can I get that product.   Sounds like the thing to use.

[75starflight]

I also have dimensional lumber for stringers in my CVZ haul, thought it was weird. Also no glass over them either. by the color of the bottom looks like yours is a 1978, but wasn't it listed as a 1979?  The foam I used from express comp. doesn't hold water, it flows right through it. I found this out when some water got under the tarp when I was working on phoenix rising. I did not have the drain hole drilled so I tilted the hull all the way up and let it drain into the bilge. I ended up vacuuming out about 2 gallons of waterout, so I dug into the foam and it was dry as a bone.

[dorelse]

I'm with Jerry...fill it up, seal the wood up and forget about it. 

[kert0307]

I'm with Jerry...fill it up, seal the wood up and forget about it. 

That's the way my floor is... Poured this under my floor after it was down http://www.uscomposites.com/foam.html

Definitely makes the boat more rigid.

[dgmeyer]

Good story Jerry, the only thing I would add concerning a bilge pump is that it is only the best money you can spend if it has an automatic float switch.

I agree with the automatic bilge. It lets you know right away if there is a water problem. Say you forget the plug , driving and plug falls out, you tear open the bottom, frost plug comes out of engine, hose fails, ETC. You don't need to wait until you see water coming over the floor before you know there is a problem. Once the engine well is full of water and it starts showing on the floor the lower pulley is submerged in water and flinging water everywhere in the engine compartment potentailly killing the engine. Then you are stranded and if you cant make it to shore better get the life jackets or hope there is enough foam to float your boat.

I have went back and forth on foam on the 23 and i am thinking I will foam for the strength and sound quality it will provide, but I am thinking that I will leave some kind of gap so that water/ air can pass threw and into the bilge. I have been trying to figure out a plan to do it. Couple ideas I have came up with would be a tube or PVC of some sort laid in while foaming then pull it out leaving a void for air/ water kind of like a drain tile. Another option I thought of would be a balloon like they make animals out of. They are long and skinny then I could just pop the balloon and would have a void. Last I have seen where people put "liner" or something in the cavity, pour in foam then cover it and let it dry. Then remove the liner and you have a foam block the exact size of the cavity you then could shape or cut out what ever you want. I don't think this method would add as much strength though as it would not be bonded to anything just floating around in the cavity but i suppose you could glue it back in once you shaped to how you wanted to.

I foamed my GT160 under the floor and it definitely made it sturdier.  Used about 90% of a 1 gallon each part kit.  I put pull noodles with holes in the middle along the keel to create an air passage to help it dry out.   I plan on cutting pool noodles into 24" lengths and putting them where the flotation boxes are.  I am going to make the front of the boxes removable with a few stainless screws so I can get in there if I ever need to for rigging or inspection.   I'm also thinking about creating some bundles of pool noodles and just wedging them under the bow or zip strip them to the cross member.  I bought two cases of pool noodles at the dollar store for $1 each at the end of the summer.   I boat in a deep lake so I feel like I need the flotation.   I also have the experience when I was a kid boating in an old Arrowglass tri-hull that would regularly swamp over the rear if you stopped too quickly.  It was sort of frightening sitting there waiting for the bilge pump to catch up.  It had a Tower of Power that must have set up high enough not to ruin the motor.   We were a bunch of 18 year old kids that probably didn't know enough to be frightened.

[WetRaider]

Red's foam is impervious to water and sets up quickly.  Most Coast Guard approved flotation foam should be … it should all be a closed cell foam.  I imagine the difference to be in the expanded & cured densities (this is why you can get a 2 / 4 / 8 cu. ft. cured size from the same 2 gallon A & B mixture).  Over time, I'm sure all the foams will degrade.

Shawn, I think the heat from the curing foam would pop your balloon before it did you any good.  If you want to make a path for water to drain and travel, cut a swim noodle in half and tape it down in the corner on either side of that keel stringer.  It is flotation foam itself, and won't take on water, and your pour-in will stick to it like glue.

[Burnin Daylight]

This how Red did Burnin Daylight.

http://www.olered.com/Intimidator.html

[makinwaves]

Mike and I have discussed this in length.  I haven't tried to sway him but my thought is to leave out the water absorbing, weight adding, wood rotting foam.  In my GT-150 restoration I made sure each stringer (3) had drainage at the stern and added vents in each cavity (2) up front.  If any water gets in it will easily drain out and the air vents will allow the hull to dry out quickly.  Thanks to the FOBG's I coated my stringers and floor with a resin/ acetone mix.  They should outlive me.  Short of a catastrophe, a high capacity bilge pump with an auto-float switch should keep me afloat.

[dorelse]

I hated not having foam in my B**liner after having pulled it all out.  Noisy, hollow feeling boat that seemed to allow more hull flexing than I wanted.

After having experienced both, I'm firmly in the foam camp.  So much quieter, totally solid and supported throughout...I will always foam, regardless of the safety aspect.

If the wood is sealed properly, so water can't get in, the foam will always be dry, and you won't have condensation issues b/c there are no air cavities for it to sweat.

But, I totally understand others want the free airflow...but foamed, done properly, will outlast me on this earth...

[OleRed]

my thought is to leave out the water absorbing, weight adding, wood rotting foam.

all foams do Not absorb water, a closed cell polystyrene will not absorb water, I know of boat house's
and docks that have been floating on it for more than 40 years, I use a polyurethane foam I come across a couple years ago that is impervious to water, is designed to set telephone, electric poles, flag poles and fence post in just a few minutes, it weighs 9 pounds a gallon, two gallons, part A and part B mixed together expand to 33 gallons, not much weight compared to the safety aspect, sound, and rigidity it adds to the hull of a boat, the GT-160 of Jerry's Okie Dokie has less than the two gallon kit in it, stuffed full, you could actually peel the fiberglass bottom off that little boat and still go boating

[wexrocks]

Be sure to allow the foam to free rise, or at least multiple vents and keep adding small amounts to fill. Too much foam in a small area will not only completely distort the hull bottom, but can also do serious damage. I've watched these types of foams rip numerous 3" screws out of a wood box.

[Plugcheck]

     Foam and fiber materials are on order from US composites(significant cost savings over express composites, sorry).    I read the instructions and the foam requires 80 degree temperatures to fully expand.   Apparently at 60 degrees the foam will only expand to 1/2 its possible volume?.  I will raise the shop temp to 80 to pour, then after expansion drop it down to the normal 60-65.    Several members have suggested pouring then cutting, has anyone ever tried to cut it with a hotwire(Nichrome wire)?   Seems like it would make for a nice flat cut.   Right now it seems the stringer design is getting the better of me, seems like I have a lot of time trying to make them fit just right.   The floor actually tilts down at a point roughly 8.5 feet from the transom.   Verified in the rotten stringers, there is a definite angle of the floor change.   Seems odd, but I am somewhat concerned the jump seats up front may not fit correctly if I install the floor level.   The floor had been repaired previously, but I suspect the stringers were original.   If it helps, the break point, or floor tilt, change is roughly in the area of the steering wheel going forward.

[wexrocks]

Just a quick note about the temps mentioned... the air temp will really not make as much of a difference, you need to make sure the material is up to temp. this can take quite a while (days) to get the temp right throughout the bucket (or barrel) of material. I have received material in the past that was stored and delivered cold, and used it right away, determined necessary volumes, then used again weeks later after being stored up high in a heated shop, and found that the expansion rate had doubled or maybe even tripled. I'm assuming you are not working with 55 gallon drums, so the time it takes to bring the temp up throughout the material shouldn't be nearly as long. Just thought I would mention that, so you get the correct results.

[OleRed]

Just a quick note about the temps mentioned... the air temp will really not make as much of a difference, you need to make sure the material is up to temp. this can take quite a while (days) to get the temp right throughout the bucket (or barrel) of material. I have received material in the past that was stored and delivered cold, and used it right away, determined necessary volumes, then used again weeks later after being stored up high in a heated shop, and found that the expansion rate had doubled or maybe even tripled. I'm assuming you are not working with 55 gallon drums, so the time it takes to bring the temp up throughout the material shouldn't be nearly as long. Just thought I would mention that, so you get the correct results.

Good Point Stevie-poo
thats why the Fox complains about our electric bill each month,  rather than bring the material inside the house, I keep my shop temp 75 degree's, and higher when I'm going to be running glass or foam the next day or two, the project is warm .. doing that now.

[dgmeyer]

I put mine in this summer when it was 90 degrees so no problem there.  One thing the guy at the fiberglass supplies store told me that was really helpful was to whip it up with a paint stirrer on an electric drill.   I just hit it for about 5 - 10 seconds after mixing the two parts and I think it did the trick.   I had a container of acetone nearby to immediately dip the bit in to clean it up before the Styrofoam cured.   I echo the comments about working in small batches because the stuff really expands and I ended up cutting some off where it got higher than the stringers.   I can also see where pouring it under floors through access holes could get really tricky.

No foaming for me here today....12 inches of snow, zero degree weather, and 30MPH winds.    Don

[wexrocks]

I mix with a smaller paint style mixer on a regular higher speed drill. I start by spraying the mixing bucket with cooking spray heavily... helps to bust up and remove residual foam in the bucket. I use plastic buckets with measurement marks, put in the lighter viscosity part first (helps in mixing to have the thicker poured in second, the thinner material will stick to the outside less and mix better and faster). Once both parts are in, I immediately mix with the drill continuously for a thorough mix, plus more mixing aggravates it more creating more expansion. Different brands react different. Some, as you're mixing, will turn a brown transparent color briefly right before expansion begins. Others will just begin expanding when mixed and ready. I then pull the drill out still spinning and "fling" off as much as possible, then quickly dump the foam out of the bucket, and quickly scrape out the bucket with the long narrow wood shims (real cheap and lots of them in a bundle!). If you have an extra person, they can be spinning the drill in acetone while you dump the foam. I usually just go back and scrape the mixer after it sets (I spray it with cooking spray first also). I'd rather spend the extra time mixing to get the most out of the foam and go back and clean the mixer rather than stop mixing early to clean the drill. These are the tricks I've learned over about 20 years of playing with this stuff, and certainly not necessarily the best way to do it, but it's how I've personally had the best results.