Latest Lightweight, Rot Free Panels for Projects

[jimbunyard]

Made a couple calls before Christmas, but unfortunately neither of the manufacturers have gotten back to me. Baltek used to make flat end-grain balsa panels laminated on both sides with 6 oz cloth and polyester resin, which were light, strong and inexpensive.
We just called it 'Baltek'

According to their regional sales rep, they no longer are in that business; there are apparently too many combinations of core and laminate for them to keep up.

There are a multitude of 'custom laminators' out there though; one of the people I contacted seemed to think that 4 4x8 sheets was not a problem for any of them. An on line search might yield one close to you (because freight will be a significant part of the cost for such ungainly items).

Rigid, 1/2" end-grain. unlaminated balsa panels cost about a third less than the cheapest 1/2" PVC or PU panels I could find. You should be able to find a stockist in south Florida, or at least one who could order it on a stock order to save freight.

Laminating formica direct to it with contact cement should yield a strong bond, but if the panel still wasn't stiff enough, it could be laminated with 6 oz cloth and polyester resin at relatively low cost, and then have formica laminated over that...

[2020]

back to opriginal poster, these two are worth a look
https://multipanel.com.au/other-industries/marine this one i like coz you can heat curve and bend it
this one coz its so easy to work with for flaty square shapes.
https://www.industrysearch.com.au/un...-sheet/p/74938
both are fire retard mold and water proof and heaps lighter than ply

[2020]

better brochure downloads is here
http://www.lustrefx.com.au/content-i...l_brochure.pdf

it's proving pretty popular in OZ (no personal connection except as a customer7 user occasionally)

[jimbunyard]

Originally Posted by 2020

better brochure downloads is here
http://www.lustrefx.com.au/content-i...l_brochure.pdf

it's proving pretty popular in OZ (no personal connection except as a customer7 user occasionally)

Looks an awful lot like standard 6 lb/cu ft polyurethane foam, which seems unlikely to check Chotu's 'low cost' box.

T'would be interesting to know as well what their "non-petroleum based polyol component" is, and just how 'green' it actually is, since they're using that as a marketing tool. Wonder if it has anything to do with palm oil...durable-use plastics from hydrocarbons can be one of the (mostly) legitimate uses for those hydrocarbons.

[GRIT]

I just bought some gurit GPET foam from Noah’s, $106 CAD a sheet, 4x8. They also have a US website.
I haven’t used it yet. I believe it’s friable, but I’m using it for cabinets, and such, so I don’t see a problem. I’m considering laminating some veneer to both sides, as I find my really light constructions weigh 30% more, once I’ve faired and painted them. And, take 200% more time. Veneer should speed things up.

GPET is 90kg, or about 5.5 lbs.

Honeycomb is relatively cheap, all our interior furniture is honeycomb. It’s a pain to finish the edges, and takes more fairing than foam, if you’re vacuum bagging, or even hand layup, but veneer laminating, and ply edges, is fairly quick, and light.

On my last two monohull Rebuilds, we used plywood for all cabinetry, and never had an issue.
There isn’t any wood on this one yet, and I’m having a hard time, like you, getting myself to transition to wood.

Cheers.
Paul.

[Chotu]

Thanks, Paul!

Didn't see this response.

I'm reopening the discussion after having some issues still.

The test panel with XPS foam wasn't to my satisfaction. It was too "squishy."

So, what are the absolute cheapest, lightest, structural cores available?

Don't worry about the outer skins. I have that part covered. I just need to keep the cost down. Even $100/sheet is more than I'm hoping to pay since it's barely structural work. Ideally waterproof would be nice, but balsa and aramid honeycomb are in consideration. I've seen something called plascore. Anyone use that?

Really looking to keep costs down. That's priority #1. Priority #2 is weight.

Thanks!

Any core

[exMaggieDrum]

Originally Posted by Chotu

Thanks, Paul!

Didn't see this response.

I'm reopening the discussion after having some issues still.

The test panel with XPS foam wasn't to my satisfaction. It was too "squishy."

So, what are the absolute cheapest, lightest, structural cores available?

Don't worry about the outer skins. I have that part covered. I just need to keep the cost down. Even $100/sheet is more than I'm hoping to pay since it's barely structural work. Ideally waterproof would be nice, but balsa and aramid honeycomb are in consideration. I've seen something called plascore. Anyone use that?

Really looking to keep costs down. That's priority #1. Priority #2 is weight.

Thanks!

Any core

You have given your intended usage through this thread before. I don't remember the total square footage of panels you are planning for. If it is not a really big number the overall cost savings might seem insignificant with all the other costs associated with your project. Manufacturers are dealing with thousands and thousands of square feet so small savings can add up. I have found myself going to excessive measures to save a few dollars when other factors (and costs) are far more important. I'm not suggesting that is the case with your project but it is a decision point we all have to deal with.

[GRIT]

For light use panels, maybe in a pantry, or closet, with a span of less than 2 feet, I'd strongly consider 1/4 inch aircraft plywood, ( home depot) sometimes called Russian ply. It has roughly twice the number of laminations as regular, or marine plywood. It's very stiff and dimensionally stable. It resists warping very well.

Even regular marine ply, at 1/4 inch, can work well in smaller spans. Just screw it onto 20mm cleat stock. Though 1/2" is my preferred thickness for shelving, I have used 1/4 for really light shelves. Lasted 8 years, and was going strong when we sold her.

[Chotu]

Originally Posted by exMaggieDrum

You have given your intended usage through this thread before. I don't remember the total square footage of panels you are planning for. If it is not a really big number the overall cost savings might seem insignificant with all the other costs associated with your project. Manufacturers are dealing with thousands and thousands of square feet so small savings can add up. I have found myself going to excessive measures to save a few dollars when other factors (and costs) are far more important. I'm not suggesting that is the case with your project but it is a decision point we all have to deal with.

It's a 50' x 25' catamaran. Entire interior cabinetry. So cost, weight and speed of construction need to be balanced out.

I also need to have it look great so Formica surfaces are needed.

It's just the core I'm stuck on. Need the absolute cheapest 1/2" core material. Does anyone know exactly what core that is?