My Floor on a Sea Ray 1972 Pics

[drewmitch44]

On my new to me project boat i noticed that the prev owner replaced the floor cheaply. The floors should have been laid out horizontally. The plywood seems only 4' wide and there is a bit of a gap between the floor and the last stringer. width wise that is. I added pics. I didnt notice it til i pulled up the carpet and the vinal pannels off the sides where they met the floor. Ive seen the stringers in a few places and they are dry and solid. I also rode in this boat for a couple of days last year. Last owner glassed in the floor (verry light glass layer) but it looks like i want to redo it so that it runs horisontally. So the wood runs all the way to the edges. I purposly left it uncovered tonight during a thunderstorm and sure enough water pools up in the back corners where the wood wasn't wide enough to let it drain right to the bildge. You think i should start the floor over????

 

[tashasdaddy]

Re: My Floor on a Sea Ray 1972 Pics

i reall can tell by the picture, but the plywood should ran across the boat. if the boat was 8 feet wide and 16 long you would use 4 sheet, with the 8 feet direction running across the stringers. run the other way the ply will feel mushy, between the stringers.

 

[sdunt]

Re: My Floor on a Sea Ray 1972 Pics

Decisions, decisions..

If the gap is small 1/2 inch to less than 1 inch, I might be inclined to grind down the area and make some chopped fiber reinforced filler http://www.shareaproject.com/pages/imageDetail,p,148,i,2869,00.html

and fill in around the edges. Grind down the top surface of the existing glass with 36 grit paper and add a couple of layers of glass over the existing. You probably also want to tape over the edges that you fixed first.

I don't agree with Tashadaddy (sorry man - we all have opinions you know) that the different orientation of the plywood will affect whether its spongy or not. As a carpenter all sheet materials are designed to have nearly equal strength in either direction.. That's why the direction of the grain in each layer of the plywood runs at different angles.

The plywood in my boat runs front to back and the floor is not spongy. It is more important that the joints and edges of the plywood are over something solid. Every joint should be over a stringer or a frame..

I apparently didn't take pictures of the framing I used to join the floor panels on my job, but here is the explanation: http://www.shareaproject.com/pages/imageDetail,p,148,i,3424,00.html

Also you can slightly extend the size of a plywood panel, if you do it right..
http://www.shareaproject.com/pages/imageDetail,p,148,i,2766,00.html

Keep in mind all of the layers of plywood are held together with glue, and every available modern wood glue is actually stronger that the wood itself, if used properly according to directions.

Watch Norm Abrahm's (The New Yankee workshop http://www.newyankee.com/index.shtml), he uses glues correctly. He always applies wood glue to BOTH sides of the joint before assembling.. You need to do that wet out the wood on both sides. And, don't over clamp the joint, you will literally squeeze all of the glue out of the joint and there won't be any glue left in the joint. Folks that crank their clamps down as tight as they can are asking for joint failures. Your clamps are there to hold the materials in position until the adhesive in the joint sets up, and thats all.

Oh, and gluing MDF, which you would not use in a boat, is unusual because is soaks up glue like a sponge. You have to pre-treat the edge with glue, let it dry and then apply a 2nd layer and assemble.

Sorry - the carpenter will now get off the soap box..

 

[Robj]

Re: My Floor on a Sea Ray 1972 Pics

Hello there,

Sorry sdunt but TD is right. Plywood is stronger in one direction than the other. I believe when you lay a 5/8 inch floor there is a direction to lay the plywood in relation to the joists. Same with a boat floor, you want the grain of the outside layer running perpendicular to the stringers. You see martial artists break wood, they always do it with the grain, because it is weaker in that direction. Yes the direction of grain changes with the layers, but you want the outside layer running perpendicular to your supports. Do a test, cut two pieces of ply and and try breaking it with and against the grain of the outside layers. You will see there is a noticable difference, I am 100% certain of this.

The plywood that I am using for my floor is 1/2 inch exterior grade with 4 - 1/8 inch layers. There is a noticable difference in floor stiffness based on how the grain is oriented in relation to the stringers.

Drewmitch44, if your floor is otherwise solid, I would just fill the low spots with filler, sand and refinish. If you are really worried about strength, add another layer of glass. Ideally you want a gap between the floor and the hull, about 1/4 inch, and fill that with a putty mixture. Why create more work for yourself by replacing a good floor? Use it until it creates problems and then replace it.

Have a great day,

Rob.

 

[drewmitch44]

Re: My Floor on a Sea Ray 1972 Pics

you know what, your right robj. I think im going to sand the whole floor down and glass it in. Walmart has fiberglass mat and fiberglass cloth. It comes in 8 square feet packages. They also have the bondo resin with a hardner. Last night i tried out the mat-resin-hardner on a piece of the splashwell that had a small crack in it. I think i did ok its solid. Is this glass mat and cloth from wallyworld ok to use on the floor? its all the bondo brand. Also what can i use to fill in the cracks between the floor and the hull? Can i cut pieces of ply for the bigger areas and just glass it down? And do i want to use mat or cloth for the floor? For my first time glassing last night im pretty happy with how it came out. Ill do it a little different next time but its solid as a rock. Thanks for any tips.

 

[Robj]

Re: My Floor on a Sea Ray 1972 Pics

How big is this gap that we are talking about?? If not too big I would just use filler. The boat has been this way without any problems for the last two years so I would think that major repairs may not be required? As far as Wallyworld brand glass and resin, I would not use it. Go to a plastics supplier and get some good quality waxed resin. I have heard people on this forum complain about the Bondo brand. Rough it up with at least 40 grit paper, I use 24 grit on an angle grinder, wipe it down with acetone and you are good to go. A fibreglass roller to remove bubbles works great and is a worthwhile investment.

Have fun.

Rob.