closed cell foam |
Post Reply |
Author | |
todd
Newbie Joined: January-03-2004 Location: United States Status: Offline Points: 23 |
Post Options
Thanks(0)
Posted: January-21-2006 at 6:24pm |
First off, thanks everyone for all the info on this site. I am in the process of replacing the floor on my 1982 nautique. I have dried the stringers and have glassed them in. They were in pretty good shape. I went back with marine grade ply and I am getting ready to pour in the urethane foam. any tips on doing this. As it is expanding, can I apply pressure to help it fill in all of the cavity, or do I just let it expand and then trim away and buy more if needed.
thanks, Todd |
|
David F
Platinum Member Joined: June-11-2004 Location: United States Status: Offline Points: 1770 |
Post Options
Thanks(0)
|
I do not understand. You say you went back with marine grade plywood. So, how are you going to pour in the foam if the floor is in place? Am I missing something here? Also, Marine Grade plywood is just a fancy way of saying structural grade plywood in that there are no voids in the laminated layers...and the cost is very high. Marine Grade plywood rots just as fast as regular plywood. So, what I am saying is that ALL sides of the plywood MUST be sealed against moisture.
If you have already installed the floor, then I suggest you forget about the foam. If you try to pour the foam through holes, it will not fill all the voids/spaces and you seriously risk bulging the hull from the created pressure. The proper method is to pour in the foam BEFORE the floor is installed. The foam is allowed to expand above the floor level and then is cut/sanded to proper elevation. |
|
kscarter
Newbie Joined: December-19-2005 Location: United States Status: Offline Points: 9 |
Post Options
Thanks(0)
|
I think I understand what he is asking and I have the same question since I'm almost to the point of being ready to add foam to my floor replacement project.
Can I pour a small amount of foam into the cavity and cover it with a piece of plywood that has waxpaper under it. The idea would be this will cause the foam to expand down the cavity instead of out of the cavity. The plywood would be held down by standing on it while the foam expands. If the foam pushes the plywood up some, it can still be trimmed and the waxpaper should keep the foam from adhering to it. Start at the back and work towards the front a section at a time. This should cut down on the amount of waste and cleanup. My project is on a Malibu Skier but I follow this site since it provides more info on mid '80 boats that other sites I have read. If anyone would like to see pics from my floor replacement or tower project, go to this link http://home.bellsouth.net/p/s/community.dll?ep=87&subpageid=236846&ck= |
|
todd
Newbie Joined: January-03-2004 Location: United States Status: Offline Points: 23 |
Post Options
Thanks(0)
|
Thanks for the inputs, but I started pouring foam today. My 82 nautique only had wood below the seats back to the front of the engine box. I traced the old wood and went back exactly like this. My floor was only bad back to the engine box so I took out foam only back to the engine. I tilted the boat on the trailer so the foam would pool at the old foam and expand toward the opening at the front of the plywood between the stringers. I am only pouring a small amount at a time. This worked great on one side, but the other side did not expand as much, I think because of the lower temperatures. There is a gap between the foam and the bottom of the ply. I am going to figure a way to fill this in. I wish I had a little more time to work with the stuff before it starts expanding. In the open areas I guess I will pour and sand away till it is level. By the way I bought my foam and fiberglass at uscomposites found through this website. I have been pleased.
|
|
David F
Platinum Member Joined: June-11-2004 Location: United States Status: Offline Points: 1770 |
Post Options
Thanks(0)
|
Todd:
Ok, I understand now and you should be fine with your method. You will have to get creative in trying to fill the small gap left behind. For instance, when I repaired my '93 SN, I wanted to replace the thin foam layer on the inside of the side of the boat (bow under carpet). I scratched my head for a bit and then decide to "paint" the foam on using a foam paint roller. I had to work fast and dispose of the foam roller after each application. After about three applications, the foam was thick enough to sand smooth and match the countour I was looking for. Point is, thick outside the box and I am sure you will come up with a way. You might even try the foam in a can that is used to seal windows and such. kscarter: You are thinking outside the box, and maybe it will work. You will need to pour in the foam in stages until it is close to the bottom of the floor, then you can try your plywood idea. Let us know how it works. |
|
Atmspltr
Senior Member Joined: May-04-2005 Location: United States Status: Offline Points: 170 |
Post Options
Thanks(0)
|
Not bad..here's the way I did it...
I used 1/2" regular plywood...the boat is 57" wide at it widest point (67 Mustang)...that meant plywood had to be laid side to side (>48" wide)...I cut all sections from front to back with about a 1/4" gap at the gunwales...once I was satisfied with the fit, I removed the sections (4 sections) and coated them generously with polyester resin and let it cure...once I was ready to foam, I screwed the back section in and tilted the boat on the trailer to as much as I could get (no motor in boat)...with rear deck panel in, I poured liquid foam (US Composites 2lb density) down each chamber (4) with enough to fill the chambers when expanded...it doesn't take long...once that's in, screw the next deck section in and repeat the process until you're pouring in the bow of the boat to fill the front chambers...the gap at the gunwales allows for expansion and ensures it's full of foam...once it's all cured, go back and trim the excess from the gunwales...I went back and glassed (w/fabric) the deck seams and the deck to the gunwales for watertightness and structural integrity...it's rock solid. I bought 10 gallons (5 gal foam, 5 gal catalyst) and had some left over to set the gas tank. |
|
Post Reply | |
Tweet
|
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |