V-berth platform

[fred1diver]

Hello everyone
I am starting the process of getting th wood for our new V-berth platform, do you think ½ inch is sufficient?

 

[dlochner]

Probably, but depends on the support beneath the platform.

 

[jssailem]

Sure, as long as you have an adequate frame under the platform to handle the jostling about that may occur on the V-Berth.



It is all about spreading the stress. 3/4 would add weight but allow a more open frame structure as the platform thickness will spread the stress.

 

[Project_Mayhem]

My O'Day 25 had 1/2" but it wasn't much bigger than 12x18". Can whatever you are building support your full weight on one knee or foot?

 

[fred1diver]

Ok, so I will get ¾ inch ply, thank you all for your quick replies

 

[FastOlson]

Either half or three quarter thickness would add a Lot of weight where you do not want it (like, in the ends of the hull).
I would advise some foam-core panels, or make your own with 1/8 inch door skins and raw foam. That's a big panel.
For comparison, the factory balsa-cored all of the interior flat panels in our boat. John's comments about the support and the area to be bridged are really the key to the project question, too.

 

[dlochner]

Ok, so I will get ¾ inch ply, thank you all for your quick replies

¾" is probably way overkill. If there are supports about 16-20" apart ½" will be fine. The boats I have owned from 22-36 feet all had ½" or ⅜" ply for the platform.

The photo below is from a Sabre 30. The plywood is all ½". Note the plywood is doubled up where the hatches are located to provide support for the hatches. There is also a vertical piece that runs along the centerline above the holding tank and rests on the 2 partial bulkheads/tank restraints that are tabbed to the hull. This provides plenty of support. The V berth on my 36 is built in a similar fashion.

 

[fred1diver]

Ok, thank you for the info
Ours has a lot of open space under it

the waste tank will be replaced by a solid one and hopefully a new water tank as well

 

[jssailem]

That is a lot of open space. My fore-berth area is criss-crossed with 3x2 beams that form a lattice from the hull to the mid and a bulkhead that runs along the keel to the bow. The structure provides more than adequate support for the 3/8" thick v-berth deck and 3" thick foam pad.

 

[mermike]

Coosa board is expensive, but very light. You might consider a sheet of 1/2" with glassed stringers underneath.

 

[dlochner]

Oh, you have a big project. The speed and depth sensors will have to move to have a tank of any size. Sooner or later the sensors will need replacing and removing the tank to access them will be a major PITA, especially if one begins to leak.

There will need to be a ledge around the perimeter of the tank to support the platform. Then added a partial bulkhead on the fore and aft sides of the holding tank that extends up to the platform level. A center support running across the top of the tank will support the middle of the platform. Doubled up ply to support access panels will further stiffen the platform.

All this support will be necessary to prevent the platform from bowing under the weight of you and your significant other unless both of you are particularly dainty. Even ¾" ply will likely bend and or put a lot of tension on the edges which is why the center supports are necessary.

 

[Foswick]

I would build a scaffold/frame that fits over this opening - so that it is supported around the periphery and, at minimum, down the centerline. I would be inclined to make another crossmember that runs perpendicular to the centerline. This would allow you to divide your panels into 4 smaller pieces. This makes access a bit more convenient. And, this also allows you to use thinner plywood - maybe even 3/8?

 

[fred1diver]

Ok, thank you for the input
As for the speed sensor, it is no longer in use, the only one still working is the depth for the chartplotter, the tank we are looking at will end about a few inches before the depth sensor.
Yes everything will be framed to secure the tanks.
The water tank will be in the forward section. That one we are still looking at different options.
As for the platform, yes we will make cross members to help secure everything in place

 

[fred1diver]

Ok, so we are finally starting the project, we ended up with ¾” just because of the price, it was given to us
We are still working on the actual tank dimensions, but I think with the platform partially in place it will be easier to see exactly how high I can go.

we will start the install by the end of the week.

 

[fred1diver]

Here is a quick update, nothing has been secured yet!
I will install blocks on the underside to support the sides before installing the platform
In place.
When I receive my tanks (water and waste) I will be able to see the size of the openings needed.

 

[fred1diver]

Hello again everyone
We are getting ready to buy the tanks, we are just wondering if some plywood can be removed, one of them is structural, it is easy to see it is structural, but the rest? I am not sure, if I do remove them it gives me more space for tanks, I would reinforce, add more panels in different Location to strengthen after the tanks are installed.

so my question is, do you think it is safe to remove the front V-panel and its shelf? And the big panel that separated the water/poop tank from storage?

Thank you in advance

 

[kappykaplan]

Sure looks like they provide some structural support to the bow.

 

[jssailem]

In for a penny, in for a pound.

The structure is not for the berth; it is to maintain the hull shape, so if you hit something in the water, the hull does not collapse inward.

Additionally, you want to limit the weight you put onto the bow. Already, you could have a chain and an anchor rode. It is wise to have limited bow weight so that as you enter into an oncoming wave, the bow flotation causes it to rise up and over the wave rather than bury itself into the wave and have these seas wash up and over the deck.

Water weighs in at about 8 lbs per gallon. Putting that gallonage near the center of the boat improves the ride of the boat in unsettled seas.