Q re Design of master berth in a 560

[Jackie J V]

When I was prepping the boat for hibernation, I pulled up the mattress in the master stateroom and found a few large "soft spots" in the board supporting the mattress. When I took up the board, this is what I found:

For whatever reason, there are cut-outs in the support board. The white backing in the pic is simply the fabric covering the top. That centre square is between 2 and 3 feet on each length.

The mattress itself is reasonably firm, but not designed to provide support across that expanse and thus sags into the gap. Before I go and replace the plywood, does any one know why Sea Ray would have designed it this way? It's got me stumped. Surely to God they're not trying to save 2lbs of weight on a 50,000 lbs boat (dry). Is there a possibility it has some purpose?

Paul

 

[HUMPH]

It almost looks like they were trying to provide a surface that gives a bit more so the mattress isn't on such a hard surface?

 

[Jackie J V]

Maybe Ken, but if that was their intent, they failed miserably. The thing sags just enough to make the back ache.

I was noticing my back more over the summer and thought that maybe the mattress was starting to go. It's not like there's a big droop that's visible.

The cut out sections match up exactly with open areas/compartments below the berth. Could be used as more storage I guess, but it wouldn't be very accessible.

Paul

 

[HUMPH]

Maybe Ken, but if that was their intent, they failed miserably. The thing sags just enough to make the back ache.

I was noticing my back more over the summer and thought that maybe the mattress was starting to go. It's not like there's a big droop that's visible.

The cut out sections match up exactly with open areas/compartments below the berth. Could be used as more storage I guess, but it wouldn't be very accessible.

Paul

That sucks, such a beautiful boat you would think they would have put more thought into the main berth comfort. Our next boat will be getting a new mattress, probably a memory foam cut to fit.

 

[dgrumm]

We found the exact same thing on our 400... And i am still baffled as to why!?

 

[Southpaw II]

It's probably designed that way to allow ventilation and the escape of moisture from the mattress. When new, the mattress was a bit firmer, I suspect.

Don

 

[OldSkool]

Looks like they used the same CNC machine to cut the bottom berth support as the mattress support. One set up for two pieces? Are they the same cut outs?

 

[Jackie J V]

Could be related to moisture release and maybe your correct Don in that the mattress was firmer 10 years ago...who knows. The mattress seems to be in great shape otherwise. Given the hours on the boat when we got it, I really don't think that bed was used all that much by previous owners.

Moisture could be an explanation. That open design only addresses the top half of the mattress though, so the bottom half would still encounter moisture issues if that were the concern. Also, I never had that issue with previous boats.

The only other thing I can come up with, is perhaps its designed to baffle sound. The spaces in the plywood do line up with the spaces below. Also, the area underneath is the front of the bow (is that redundant?) near the water line. My guess is that if the top were solid, waves lapping or pounding on the bow would echo through that space.

I think I'm just going to go ahead and replace the plywood with one solid piece and fill the space with some acoustic dampening material. I'll need to find something mold resistant to be sure. I think I'll also add a layer of memory foam to top of the mattress as well. We probably slept on that mattress for 80 nights or so this year.

Paul

 

[Jackie J V]

Afternoon project was to fill in the cut-outs. This is a pretty specific issue, however if you're encountering the same issue on the same boat, here's some info on what I did:
- The plywood already there to support the mattress is 19/32" marine grade plywood.
- It would have been too much of a pain to replace the entire piece of plywood - as the fabric was glued to it and the edges along the front were angled just so, to fit the curvature of he hull.
- Given that the existing plywood sits on top of fibreglassed supports, support bracket for the fill in pieces would have to be recessed - no big deal.
- I used 1/2" standard grade plywood deck tie straps for supports and 1/2" screws.

Here's the next-to finished product. I just covered the strapping with gorilla tape to protect the fiberglassed supports from the screw heads.

The straps are all recessed so everything will sit flat. When I put it back in the boat, I'm going to glue some mold resistant underlay to the bottom for acoustic dampening.

Paul