Latest Lightweight, Rot Free Panels for Projects

[Chotu]

Let's face it, making panels for projects from foam and fiberglass takes a lot of valuable time.

Sometimes spending a bit more for a pre-made panel can save you money in less time needed to build something.

To that end, what have some of you discovered to be some of the lightest, cheapest, most durable and easiest to work with premade panels?

I'm looking at making a lot of cabinets and interior finish stuff coming up soon. I was thinking of coosa board because I would be able to treat it as wood. They make a Nautical 15 product:


Nautical 15
Coosa's highly-economical, super-lightweight glass-reinforced panel
Density of 15 pounds per cubic foot
Typically used as a core or low-stress semi-structural component
61% or more lighter than plywood

The advantage I'm seeing with coosa is you wouldn't have to deal with a core. (I think). So installing hinges, knobs, etc would all be simplified. No edges either. Just sand a little, paint and done.

Has anyone worked with this Nautical 15?

Are there any other products you'd recommend for cabinetry?

[Bill O]

The Nautical is a good choice for non structural cabinets.

Biggest difference in the nautical vs. coosa is the coosa has f/g sheets plus strands while the N15 only has strands.

We've used both sign board and coosa for our exterior projects and think they work well. Both are fairly porous and have always been sealed/glassed them before painting. Depending on your look you are attempting to achieve, some surface prep may be needed before painting.

Gluing the boards together w/the urethane glue is fine, but need mechanical fastening and usually like to glass them for added strength.

For some hardware you may get away w/just screwing in and while hinges may eventually need a thru bolt if they start to work loose.

Its a great material and easily tooled to custom fit the pieces. Biggest down side was the dust and possibly f/g dust particles when using N15 or the coosa. (why we used sign board instead). We use better dust masks and protective clothing when doing heavy tooling on coosa.


Bill O.

[Chotu]

Thanks for that informative post, Bill.

I looked up signboard a little bit and found these. They seem to have a nice finish on them. And they are not made of foam in the middle. From what I am reading.

Could be good for cabinetry? Installing hardware into it and doing ends without a foam core is a major factor in speeding things up.

https://www.coastalcreative.com/prod...ard-pvc-signs/

Is that something like what you used?

I’m looking at panels for the interior work. Worst case would be a shower stall area that gets sprayed from time to time. The upper area. The lower area has its own special shower pan. The shower pan that rises up to about waist height.

Everything else is just plain old cabinets. And maybe some furniture.

If nautical Coosa is so porous, it may make sense for me to look around at some other panels that have a nice finish on them already. Just fitting them together and then running a bead of caulking after the bonding would be a lot faster.

[Bill O]

The sign board we used (particularly the brand, precision board from coastal enterprises) is still a HDU based product.

The PVC board looks interesting and may work for your application. I like pvc and want to use it more, except it has more thermal expansion for exterior use than what i would like, but again may be fine for the shower walls

So you're back to doing the shower stall. For the cabinets in our shower area, we made them more structural/integrated to the hull (1/2" coosa). The rest of our shower was part of bulkheads and an engine partition so it was framed w/wood. To finish that off we used smooth frp panels which also covered the coosa cabinets. Everything is easy to squeegee after a shower and very low maintenance. The frp has it place (no foam core) and could be cost effective way to make a shower enclosure (similar to commercial land based shower stalls)

I understand you want light weight, but will anyone be showering underway and possibly fall over/hit the walls. Things happen, so I tend to overbuild (a bit) which in the long run could save a lot of time/effort if you need to do a 2.0 version. I think you had pics up before of the area but don't exactly remember the layout.


Bill O.

[Chotu]

I didn’t know you remembered my post on showers along time ago. Thanks, Bill. That’s a good memory. We have redesigned a lot before the big push to finish.

It is a little bit hard to explain, but there is a natural place for the shower already. A bulkhead is involved, the hull is involved, and the hull on the other side is involved. There is a door on the fourth side. So, the sides of the shower are just going to be the hull itself. And the bulkhead. However, up high there are recessed areas for storage. I plan to build some cabinets basically at the top of the shower to help get into these areas. These are places where I can put a water maker and things like that.

As for the shower pan, I’m just going to use a flat panel that runs all the way to the hull on all sides and corners. No need for a traditional shower pan with a lip because of the way this is all fitting together.

A redesign of the space made all of this possible. We redesigned the whole interior. Probably a good idea that we did this now instead of after building. Ha ha ha

[jimbunyard]

Used it a lot. It is a good construction material, inside or out, but, as with any other, there are caveats.

Screws will not hold in it, unless it is coated with a couple layers of glass and even then, their purchase will be somewhat tenuous. Through-bolting will work, but the 15# density is still a bit soft and compression-related loosening is possible over time. For loaded hardware better to core-and-through bolt, which is time consuming. The nut's and bolt's ends on the inside may also cause problems.

One solution is to use wood 1Xs (poplar, ash, mahogany, etc) where you intend to install hardware, and screw into that as you would at home.

If you use it for doors, some sort of edge treatment is necessary, for cosmetic as well as structural reasons. The methods I've used, edging with a resin/thickener putty, wrapping with fiberglass and molding, are all a PITA and consistent results are difficult.

You might find it simpler and more aesthetically pleasing to make the doors from wood with traditional finishing techniques.

[Chotu]

Jim, I had thought about using wood. Especially doing some stick and frame. I am concerned about the weight. Also concerned a bit about the potential for rot if I don’t take clothes care of it.

But the Coosa board does not sound ideal either. Why doesn’t anyone make a lightweight panel that is white on the outside and smooth or even satin finish, that’s reasonably good for putting in a screw or two, and has fairly good edge finishing qualities?
Does such a thing exist?

[jimbunyard]

Originally Posted by Chotu

Jim, I had thought about using wood. Especially doing some stick and frame. I am concerned about the weight. Also concerned a bit about the potential for rot if I don’t take clothes care of it.

But the Coosa board does not sound ideal either. Why doesn’t anyone make a lightweight panel that is white on the outside and smooth or even satin finish, that’s reasonably good for putting in a screw or two, and has fairly good edge finishing qualities?
Does such a thing exist?

Because those qualities are not easily combined, though nature comes closest to meeting all three, which is why I suggest using a composite approach; sides, backs and bottoms of coosa, fascia and doors wood.

An alternative that I've never tried would be to a laminate full sheets of coosa with Formica, cut the panel out, and glue the cabinets together with a methyl methacrylate-type glue. Doors could be cut out and edge trimmed with Formica. You'd still have the hardware issue, and I'd still tend toward using wood for that function. It laminates with Formica well.

As for rot, unless you have a hell-of-a-leaky boat, for interior use you shouldn't have a problem with any of the woods (or woods similar in characteristics) mentioned.

[Bill O]

Can always use well nuts, etc. embedded in the coosa to securely fasten something to it if you can't do a nut in the back side.

Again would be good to see exactly what you are doing as there usually is a solution to the problem.

Bill O.

[Chotu]

Originally Posted by Bill O

Can always use well nuts, etc. embedded in the coosa to securely fasten something to it if you can't do a nut in the back side.

Again would be good to see exactly what you are doing as there usually is a solution to the problem.

Bill O.

Bill, I’m doing everything. LOL Picture an empty hull with nothing in it. That’s what I’m doing. Everything. All cabinetry, all furniture, everything.

I’m sure there will be lots of specifics, but I just want to find some materials that will work quickly. Instead of hiring a helping hand, I can maybe bang a lot of this out myself quickly by using pre-fabricated white finish quality panels that go together easily to form cabinetry.

[Bill O]

I hear you, we do all our own work.

Wish I was close by, could probably do some good brain storming to get the job done.

Bill O.

[Chotu]

Originally Posted by Bill O

I hear you, we do all our own work.

Wish I was close by, could probably do some good brain storming to get the job done.

Bill O.

Thanks, Bill! Sane here. It's always better to be close to other builders when fitting out, if only to try for some volume discounts. Ha ha.

I think if I can figure out what lightweight, prefinished panel to use for everything, it'll be a lot easier.

[Chotu]

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[Chotu]

Originally Posted by jimbunyard

Because those qualities are not easily combined, though nature comes closest to meeting all three, which is why I suggest using a composite approach; sides, backs and bottoms of coosa, fascia and doors wood.

An alternative that I've never tried would be to a laminate full sheets of coosa with Formica, cut the panel out, and glue the cabinets together with a methyl methacrylate-type glue. Doors could be cut out and edge trimmed with Formica. You'd still have the hardware issue, and I'd still tend toward using wood for that function. It laminates with Formica well.

As for rot, unless you have a hell-of-a-leaky boat, for interior use you shouldn't have a problem with any of the woods (or woods similar in characteristics) mentioned.

Jim, I've done a little wood building on this project. My single hull bulkheads are all okoume bathed in epoxy. I also tried out stick frame building with 1x2 (furring strips/strapping) and doorskin ply. It was quite lightweight but also too flimsy. The doorskin was too breakable. I painted these in epoxy and then paint to keep mold away. I have a major medical issue with mold on boats, so any wood has to be sealed up to be sure mold can't get started.

What about laminating Formica over foam? Cheaper foam? Then glue that together as cabinetry? Caulking at the corners if needed for looks? Just through bolt hardware or put wood in the core where hardware goes?

I also so this stuff, but don't know how the finished surface would look.

Check out the video building cabinets.

https://m.youtube.com/watch?v=ScEvGBlBiis

But they don't show what you do with the front face.

[jimbunyard]

Seems virtually identical to coosa, though it's a bit less expansive. Coosa's compression strength is about double, I presume because of different fiberglass composition.

If you can find it prelaminated with a finish, from stock inventory, let us know. I couldn't