depth of swim platform

[Wilson]

I'm getting ready to build a new swim platform for my 74 chb marine trader, 34 feet. Was wondering how far out beyond the support brackets I could/should go. I want to think the old platform was about 24" but I already junked it, only have pictures to go by. Any advice on how much deeper I can make it would be appreciated.

 

[Capt.Bill11]

When I rebuilt mine I added about 8" to the original depth. I also added longer SS flat stock strips to the top of the original brackets for added support. Personally I love deeper swim platforms.

 

[obthomas]

The answer to your question depends greatly on the strength of your transom and connections and the compressive strength of the diagonals. It's a simple structural engineering problem if you somewhat describe the support system and and transom connections, and the biggest dude that is going to jump up and down on the platform.

 

[Wilson]

Thanks guys. The transom is about an inch thick, glass over plywood from what I can see. We have 4 platform supports across the transom and the original platform had all thread bars at 4 spots all the way thru the platform. We are going to build it in a similar fashion with the same hardware, new hardware but same design except we are going to use some backing plates on it all in the lazarette.
The support brackets are 17" long. I'd like to get it out to 24 inches or so. We will have 1/2" all thread at 4 points along the platform as well as the brackets underneath. I will have a bait tank sitting on it, only weighs about 500 pounds wet ha. I think the old platform was about 20" deep.

 

[jleonard]

I added 7 inches to the original platform on mt 40 Albin. For support I simply put 1.5 x 1/8 stainless angle over the top of the oem brackets. It has worked fine for 7 years.

 

[rwidman]

I would go with the original size. Long swim platforms often look out of place, especially on traditionally styled boats. And remember, you will be paying for that additional length at many marinas.

 

[Lutarious]

Im planning to build a Pipe davit / Cranew system on the boat deck and remove the swim deck completely on my new (to me) Nova 44. Somebody try to talk me into keeping the swim deck, or make me an offer for the parts.....

 

[healhustler]

Regarding the depth of the swim platform, rwidman is right about the appearance of oversized platforms, but even more important is how you want to use it. My Admiral and I discovered that having a swim platform and ladder large enough to make water access easy and pleasurable would probably have tripled our usage of the boat. A marginal platform, for us, would be marginally used. I say build your platform the way it will serve you best, but engineer it well.

 

[Capt.Bill11]

I would go with the original size. Long swim platforms often look out of place, especially on traditionally styled boats. And remember, you will be paying for that additional length at many marinas.

Only if they come out and measure. Which I've never seen happen. Besides, do you really think they are going to ding you for an extra foot because your swim platform is 6-8 inches longer than standard? And how would they even know what standard is? If you tell them you have a 42' GB, Albin, MT, whatever, that is what they are going to charge you for.

 

[Wilson]

I only want to take it out to 24" from an original 20 or so, mostly so my bait tank is not hanging off the platform. I really don't think it is that big a deal with the 1/2" all thread going thru the entire thing. I could be wrong though, probably use some ss angle irons to run it out. Thanks for the ideas guys