Lightweight, Non-Toxic, Good Looking and Relatively Inexpensive Panels?

[Chotu]

Originally Posted by MicHughV

This may be a shot in the dark....

I've " glued" two pieces of 1/8" plywood together using the expandable foam you can buy at any Home Depot store and just squished the two pieces together. Once dry, it was nearly impossible to remove.

Why did I try this....I wanted a piece of 1/4" plywood with two finished veneer sides and my past experience with the foam led me to believe it would work.

that’s true. That foam is just as much of an adhesive as it is foam. Very sticky stuff.

[Bowdrie]

Originally Posted by Chotu

*no polyester, vinylester or epoxy used in construction- glue, contact cement, etc ok
*extremely lightweight- think a piece of foam, doorskin plywood, etc
*attractive - I need to finish to be perfect. The cabinetry has to be exceptionally beautiful
* Lastly, not being ridiculously expensive would be good as well

Perhaps a bit tongue-in-cheek, but jeepers, you do want to have your cake and eat it too.
"Lightness" is usually the most expensive product you can buy.
Will nobody ever fall or be thrown against any cabinetry? Will nothing ever be dropped on it, or the cabin sole?
How much weight do you envision to save? The weight of 2>3 people and a couple of full ice chests?
A perfect finish? In the end that may prove to be the most expensive goal imaginable.
Many types of foam and foam laminates can make a strong structure, but you pay for it with the work necessary to fasten anything to it and the type of work needed to form corner/angle joints that have any structural rigidity.
Grab bars, hand rails, sea rails, towel bars, even a heavy brass barometer won't hold so well to a couple millimeters of "whatever".
Eliminating the use of any Polyesters/Epoxies will by definition degrade the strength of many of the laminations/glue joints.

[Chotu]

Originally Posted by Bowdrie

Perhaps a bit tongue-in-cheek, but jeepers, you do want to have your cake and eat it too.
"Lightness" is usually the most expensive product you can buy.
Will nobody ever fall or be thrown against any cabinetry? Will nothing ever be dropped on it, or the cabin sole?
How much weight do you envision to save? The weight of 2>3 people and a couple of full ice chests?
A perfect finish? In the end that may prove to be the most expensive goal imaginable.
Many types of foam and foam laminates can make a strong structure, but you pay for it with the work necessary to fasten anything to it and the type of work needed to form corner/angle joints that have any structural rigidity.
Grab bars, hand rails, sea rails, towel bars, even a heavy brass barometer won't hold so well to a couple millimeters of "whatever".
Eliminating the use of any Polyesters/Epoxies will by definition degrade the strength of many of the laminations/glue joints.

did you read the rest of the thread or did you just stop there? Asking because there’s a lot of information about these topics in the thread.

And it doesn’t sound like you are very familiar with my boat and what it’s like to travel in it. it doesn’t move around very much. I can leave a 16oz plastic keg cup of water on a glass smooth coffee table with no fiddles all day long in the worst weather and nothing happens to it. Precisely because I built it the way you think is wrong is why it behaves like this. if I did a bad job and made it heavy, it would be a piece of junk and it would have all sorts of accelerations that it shouldn’t have. you kind of have it all backwards.

heavy brass barometer? Not on my boat. That’s a dumpster type item

Wait until you see the results. I’ll have the finish looking perfect. And it won’t weigh anything either.

I already have a galley built with far less structural integrity than we are even talking about here. Stick frame. Douglas Fir 1x2s. 5mm ply (same stuff Jedi talked about). The shelves are a single layer of 5 mm plywood. Those shelves are holding hundreds of pounds of galley stuff. it’s only the carcass because i didn’t do the finish work yet . The faces of some of the areas are single layer of 5 mm plywood. The countertop is something more. It was a more robust half inch piece of a super light plywood. I forget the wood type. still going strong nearly 6-8 years after I put it in and it’s been in use every day. no, people did not fly around in the galley and smash into it. That’s not the kind of boat I have.

and then finally cabin soles? What’s your problem with the cabin soles? you don’t even know how their construction. I haven’t mentioned that at all.

what you don’t understand about a high-performance catamaran is that every pound counts. You don’t look every little project and say how much am I going to save. you have to save every single pound at every juncture you can from the beginning you start building the boat until the end. That’s how you do it. That’s how you come out with a good boat. Otherwise you come out with a piece of junk.

There is no justifying adding weight.

every single pound that you add through stupidity or fear results in worse performance, worse handling, lousy acceleration that can spill your drink or throw people into cabinets, and generally just a bad boat. additionally, the boat is far more structurally sound if you don’t add all of that extra weight. The more weight you add the higher the forces are on everything.

if you add the big heavy brass barometer, you have to add something behind it to support it. Then that adds to the weight of the thing that you just built to support the barometer. Which adds to the force on the hull which maybe makes you increase the amount of glass on a bulkhead which adds more weight which means you have to reinforce the boat in other areas. It’s called a design spiral and it’s no good.

It’s absolutely essential to save every pound you possibly can when you build a good boat.

PS: towel racks go into the bulkheads. not into cabinetry.

[Chotu]

here you go. Here’s the unfinished galley I built circa 2016.

holding just fine to this day. Nothing has changed except the refrigerator. Upgraded to all electric refrigerator since the 1500 watts solar and lithium bank makes that, plus a dedicated chest freezer possible.

of course it looks like crap because I didn’t know how to build a galley back then and it was never finished. I’m going to take another stab at it and fix it.

but wait until you see how the process we’re talking about here comes out. It’s going to look exactly like every brand new catamaran you see at a boat show. I know exactly how to get that look now. Unlike this old dated style that I did in 2016.

those are Douglas for one by twos, 5 mm plywood for the shelves and that is all. There is no other thickness. Countertops are half inch.

everything is exactly the same now. 7 years, 3 direct hurricane hits and 3000 miles later.

i’ll be putting up pictures of the shower area and vanity area in the head once i get those done toward the early spring. launching an app right now. That’s going to take precedence for several weeks to months.

[Bowdrie]

I should have known you would respond as you did.
Yes, I have read every post and yes there have been many good ideas.
A cup of water won't move in the "worst" weather? That sounds hard to believe.
Can't afford the weight of a brass barometer? Now that is sad.
You don't have to attack everyone that doesn't see things exactly as you do.
If you want everything "beautiful" and "extreme lightweight" and still be inexpensive and without any cross-linked chemicals you've got a steep hill to climb.
That's reality.

[CaptainRivet]

Wonder why bamboo never came up till now. Water resistance by default and surface is light and modern when eg combining with stainless.
In 8mm thick massive plain bamboo they make nice doors or 5mm is enough for panels. The weight is then acceptable too.
Where more massive needed a sandwich from 5mm thick bamboo and foam.
You can keep them plain or oil or soap or varnish the surface to your liking.
Hard and very sturdy surface…

[CaptainRivet]

Originally Posted by Bowdrie

I should have known you would respond as you did.
Yes, I have read every post and yes there have been many good ideas.
A cup of water won't move in the "worst" weather? That sounds hard to believe.
Can't afford the weight of a brass barometer? Now that is sad.
You don't have to attack everyone that doesn't see things exactly as you do.
If you want everything "beautiful" and "extreme lightweight" and still be inexpensive and without any cross-linked chemicals you've got a steep hill to climb.
That's reality.

That’s not sad, it’s just another approach and mentality. And nobody needs a brass barometer anymore today, that’s already in my I Pad pro which I use for navigation anyhow…
Making it lightweight is loads of DIY work with good materials or big chunks of money if you buy of the shelf honeycomb carbon and veneered panels.

I done the same with an Audi R8 Supercar with a 150kg light Alu spaceframe and it was an art of Audi to f… that up to get that to 1800kg…I wanted 1400kg with full interior and standard OEM look and achieved it. I was standing countless hours on the driller to hole simple Alu holders to get 80g out of a 200g holder that had no structural purpose (think a hole drilled more then 200 of these holders so 200x80=16000g or -16kg), recreating panels from honeycomb with a 1mm carbon plate both sides, using titan screws instead of normal ones (the more then 3000 I replaced was -23kg at the end) …majority was laughing…till came out at 1377kg with a totally oem stock looking R8 that’s on par with a stock 911 GT3 RS with mods costing me blow 20k Euro. It’s a totally new car and suspension even being race setup is more comfortable then stock R8. Then nobody laughed anymore…

[Mark424]

Originally Posted by Chotu

*attractive - I need to finish to be perfect. The cabinetry has to be exceptionally beautiful because I am not sanding down the eopxy interior of the hull to smooth the surface. I’m going to leave it rough and paint right over it. Kind of like when you see them do that at a Whole Foods or other brand new expensive store. The cabinetry and accessories are beautiful but it’s still the old industrial building. I’m using that kind of motif because I will be able to do it more easily without exposure to epoxy dust. it’s also extremely lightweight to do it that way.

Whatever material you end up choosing you can also then add an "architectural film" to it, lots of textures, wood, leather, stone, etc. e.g. 3M Di-NOC. Search "yacht interior wrapping" on YouTube.

[Robert Jansen]

One of the lightest and most rigid possibilities is hexcel (expanded hexagonal grid, aka honeycomb. If you need insulation, two part systems, foamed in place, come to mind.


Just a suggestion.

[fijicalling]

Take a look at how the Mumby performance catamarans are fitted out. There is a bit on YouTube.

[coopec43]

Hi Chotu


Has anyone suggested looking at what they use in caravans (motor homes)