Advice for making a layered foam V-berth mattress

[Cadence]

Originally Posted by Hunky Dory

I am doing exactly as you are. I checked with a foam manufacturer ( bhart@sureline.ca )
He recommended 3" of 2050 IFD a medium firm,( test measure for open cell polyurethane foam). This product has no fire rating. Then using a water based adhesive and glueing a 1"top layer of Serene a new product that is open cell not affected by temperature. This combination does not engulf you like memory foam. Approximate cost for materials equal to queen size is $325. Canadian,

I'm glad to hear someone else thinks Memory Foam engulfs you. The most over hyped bedding product ever. If someone can find a real latex, that is rubber, in the right durometer for them it would be heaven.

[Copacabana]

Thanks for the replies. In the end I bought the gel memory foam, which is supposed to eliminate the problem with getting warm at night. It's just under 2 inches thick, so I'm hoping it will just provide a "comfort" layer. The support will come from the denser foam underneath. I will test my original V-birth foam with the gel foam topper and, if it's too soft, I'll probably change the under foam to something firmer.

Living in Brazil, a country full of rubber plantations, you'd think latex foam would be cheap and abundant. Not the case at all...

At any rate, I'll report back with the results when the V-birth is ready. Thanks for the advice.

[El Pinguino]

Looks like I'm a day late and a dollar short once again

However.... I'm always hearing about condensation under bunks etc etc.... why don't people use EVA closed cell foam? https://www.foamsales.com.au/product...yABEgIOi_D_BwE

Seems to come in suitable sizes and thicknesses...

I have it in the saloon settees and also use 4mm and 6mm closed cell for insulation.
Works good... I've never had condensation issues.

Down the back of the boat I sleep on a custom made inner sprung mattress....

[AJ_n_Audrey]

Here's what worked for me. I quickly discovered that the foam in the V-berth "mattress" that came with the boat was too thin. I had learned previously via Army and backpacking experience about sleeping pads, so I put three sleeping pads (at about $20 each) under the V-berth. The first two were in line with the bodies in the berth, i.e., mostly fore-aft, but then I realized my hips tended to be uncomfortable as they dug into the foam. So the third pad was athwartship, to add additional padding underneath my (and my wife's) hips. Thenceforth, no issues at all, and have had many a quiet sleep and a sweet dream at anchor.

Something like this, or even cheaper, does the trick:

On Amazon: Outdoor Hiking Mountaineering Foam Camping Mat Sleeping Pad in Tent Dampproof Mattress Foam

[MarkusK]

We went to our local ‘rembourreur’ (upholsterer). He expertly advised us on a dual density foam mattress. 2” softer top + 2” firmer bottom. He cut and glued the foam to fit the covers we brought to him. Very pleased with the results.

[Copacabana]

The gel memory foam arrived and I've used it the last 2 nights on my bed at home to test it before I cut it for the V-berth. It isn't hot, which was good news. It provides some additional "comfort" in that it has a nice, soft texture. It's only 4cm thick (just under 2 inches), so it doesn't really offer much support- that comes from the mattress underneath it. It was quite expensive and I'm not sure yet if it was worth it. The next test is trying it over the V-berth mattress to see how it feels. If it's too soft (my V-berth foam isn't very firm), I'll try adding denser foam under the topper. I'll report back, just in case anyone else is thinking of going this route.

[Supers0nic]

The cheapest way to go is to buy some mattress toppers at Walmart.

[donradcliffe]

Originally Posted by Supers0nic

The cheapest way to go is to buy some mattress toppers at Walmart.

Or Costco.

[Markhunter1097]

Cut to size with an electric carving knife

[Copacabana]

Originally Posted by Markhunter1097

Cut to size with an electric carving knife

I don't think I've ever seen one in Brazil.

I was going to cut it with a fine-tooth hacksaw blade or a sharp knife.

[a64pilot]

Originally Posted by Supers0nic

The cheapest way to go is to buy some mattress toppers at Walmart.

Originally Posted by Markhunter1097

Cut to size with an electric carving knife

Both of those, and if no electric carving knife, maybe use a hot wire to cut the foam.
If you have to you can make your own hot wire knife with an electric train transformer and nichrome wire. I have only cut styrofoam with a hot wire so unsure how it will work on soft foam, but any kind of knife makes a mess, best I have been able to do is with a serrated knife, but it looks like it was cut with a chainsaw.

For the bottom layer, the closed Cell dense foam that is USCG approved for floatation is excellent, I have dual layered my Settee cushions with a three inch medium density open Cell and two inches of the dense closed Cell. Works great as my butt bones don’t hit plywood now.

[Cadence]

Originally Posted by Copacabana

I don't think I've ever seen one in Brazil.

I was going to cut it with a fine-tooth hacksaw blade or a sharp knife.

A serrated blade hand carving knife will do you better than a hacksaw blade. One with the big scallops in the blade.

[uhu]

... a roundish serrated blade with little pressure, but several strokes works wonders.
like this
or this

try to avoid these "pointy" serrated blades, they "hook" too much into the foam.

[a64pilot]

The rounded may well be the trick, I can attest to the pointy ones hooking, and tearing the foam.
Scissors don’t work well either

[bcboomer]

Ceramic knives slide through foam like butter. If you can find a long serrated one it would probably work better than the electric carving knife.
I've found that, with the electric knives, you need to go slow or they self destruct.