Buliding a fiberglass swim platform

[rrrwel]

I'm thinking of building a fiberglass swim platform this winter. The boat is an inboard bridge Sportfish with a 13' 8" beam with a walk thru transom. I fish the boat boat with downriggers so the depth of the paltform will be short - maybe only 20 to 24 inches. The reason for wanting the platform is to accommadate the occasional dingy and somewhere to get off and on a Jet ski when playing around the dock.

I've read the other posts on suggested construction but It looks they they were going to build a mold and I really don't want to have to build a mold. My question is: Could I simply build it out of a coreing such as Divinycell or Balsa and then glass over it, paint it with something like Interlux Perfection with non skid added.

I'm aware of the companies that custom build platforms but I have the time and space to do it myself and would like to give it a shot. Any suggestions would be appreciated.

Thanks

Rick

[Capt Rick Hiott]

The best way to do it is to build a mold,,,,,,you will be glad you did.

If you glass over wood, It wont last.

[Cracker Larry]

If you glass over wood, It wont last.

I disagree. I build custom composite boats, glass over marine plywood, and they will last your entire life and your children's. I guarantee them for life. The trick is to use epoxy resin, not polyester, and a good marine plywood. Polyester resins are not waterproof, which is why you see so many rotten transoms and stringers in production boats. Water actually wicks through polyesters over time, this is what also causes hull blisters. Manufacturers also use cheap A/C exterior plywood as a core. When it gets wet it will delaminate and rot. If you use BS1088 meranti plywood and good epoxy resin such as System3 Silvertip, it will last 3 lifetimes longer than the hull of a production boat.

Foam core will work, but it will require much more fiberglass and resin than a wood core and may end up being heavier and certainly more costly than a marine ply core, and not as strong. It will also require more support structure.

If you mold it and use a solid glass lamination, it will be 4 times heavier than a meranti core and only half as strong.

I'd use 1/2" marine plywood core with a few 1X2 yellow pine or mahogany stiffeners, glassed with 2 layers of 12 oz. biaxial cloth. Once it's glassed you'll apply a couple of coats of epoxy based fairing compound, sand it smooth, prime with an epoxy primer such as System3 Yacht Primer, then finish with the paint of your choice.

[Capt Rick Hiott]

I always used a mold with good success..........

How much would you charge to build something like that Larry?

Edited October 1, 2009 by Capt Rick Hiott

[A Few Dollars]

Why not build it out of Starboard?

http://www.kingstarboard.com/Products/starboardas.aspx

[Cracker Larry]

It would depend on the dimensions, how fancy and the level of finish, but probably in the ball park of $2,000. For the size he is talking about the material costs would be about $700, not including paint. Good paint such as Sterling or Awlgrip will run over $300 a gallon, but worth it.

If it were my boat I'd build it from laminated mahogany just because I like the way it looks compared to glass It would actually be less expensive for the materials, but a higher labor element. Something like this...

[Cracker Larry]

Why not build it out of Starboard?

You certainly could use starboard although I'd consider it low end. Depending on the boat it's going on, it may or may not be appropriate. Not to slight anyone's boat, but if it's going on a Bayliner then starboard would be perfectly adequate. If it's going on a custom Buddy Davis then probably not.

The end result has to look good, match the boat in quality, fit and finish, and not damage or devalue the boat.

[rrrwel]

Thanks Larry,

I was planning on using epoxy resin. I have rebuilt some large cockpit hatches using this method with success. My question is would you glass the 1 X 2 stiffeners on the bottom going length wise or width.

Rick

[Cracker Larry]

I think I would first stiffen (double) the entire perimeter. If it has a lot of curve this would be easier using plywood. Then run stiffeners fore and aft on 24" centers. The mounting bracket locations will need to be doubled up also.

For non-skid I like a product called Kiwi Grip. It goes on with a roller like paint and you control the texture with the roller type and pressure. It does a great job, holds up good and is easy on bare feet. Available in several colors.

[rrrwel]

Got it Larry - Thanks

Rick