PolyMetal [I]vs[/I] Basalt fiber

[freebeard]

Times past I have advocated for PolyMetal as a construction material.


www.nudo.com/p_polymetal.php



Experiments resulted in my wanting to make a teardrop trailer from it:



However, it comes to my attention that this is the same material used in cladding Grenfell Tower, which burned to the ground! Combustibility may not be a deal-breaker for an airdam, etc., but it is for sleeping inside it. Not a problem for basalt fiber: https://en.wikipedia.org/wiki/Basalt_fiber#Properties

Thermal performance: Super-thin basalt fiber

Nano-glass-coating before adding the resin matrix makes it as cool looking as carbon fiber:


Basalt fabric with a touch of glass - Basalt Guru

Strengthening of basalt fibers with nano-SiO 2–epoxy composite coating
https://www.researchgate.net/publica...posite_coating

So — in summary — forget everything I said about PolyMetal. Thank you.

[jray3]

A teardrop and a high-rise are not very comparable on fire risk, especially given that polymetal is approved under US fire regs for buildings under 40 feet tall. (according to the Wikipedia article you referenced). Yes, if you apply two crossed torches to the teardrop skin for 30 minutes (or tip over a combustion heater), your trailer may burn. Just like all the other trailers made of plywood and filled with wood cabinetry and combustible fabrics.

The basalt fiber doesn't seem comparable because it is a fabric and not a rigid panel. I'd love to build a trailer out of fabric and resin, but it requires a lot more skill and time to make it look good and perform well than fitting together some rigid panels.
I found references to some prototype basalt wall panels, but other than simulated stone cladding, no commercial products. Is a basalt alternative panel to polymetal out there?

[freebeard]

Maybe I'm being alarmist.

I like PolyMetal because you can hand work it and it's prefinished. I just don't want someone going down a bad path on my say-so. The fire regulations are prolly about how tall their ladders are. I guess if I'm in a forest fire in my teardrop I have bigger problems.

Did I mention basalt is electrically insulative?

The trailer design I showed would require rollers 4ft wide to form PolyMetal (not undoable) But with fabric I could cinch it down over some hoops and then spray or roller it with resin. Sort of a Conestoga look.

[Stubby79]

I'm OK with flammable. (for the day when the project pizzes me off enough)

[California98Civic]

This is the thread from which I learned about PolyMetal. I am buying a similar product from a local supplier for my decklid spoiler build. Some notes: PolyMetal is only a brand name for this type of product. All the suppliers recognized my description (a layer of black thermoplastic between two layers of aluminum, usually 3mm or 6mm thickness) with different brand names: DiBond, Komalu, and AlumaCore. Don't buy it online! The shipping charges are more than the sheet, and that is ontop of product prices already 2 to 4 times as high as when I called local suppliers. Instead of $150-200+ with another 150 in shipping, I will pay $51.76 tomorrow, total,taxes included.

I hope that helps someone later down the road. Looking forward to this build a lot!

[freebeard]

Thanx.

How big a piece does $51 and change get you?

The other brands I was aware of were Alumapanel and Grimco MaxMetal. One think I like it's available in 5x10ft sheets.

[California98Civic]

Originally Posted by freebeard

Thanx.

How big a piece does $51 and change get you?

The other brands I was aware of were Alumapanel and Grimco MaxMetal. One think I like it's available in 5x10ft sheets.

It is 4'x8' and will just barely, I hope, fit into the back of my wife's Forester, sticking out the back two to three feet.

[cRiPpLe_rOoStEr]

I'd still take it with a grain of salt. How could a basalt fiber-based composite be fireproof at all if it still requires a plastic resin? Or would it be possible to replace a plastic resin with some ceramic compound?

[freebeard]

basalt.today: Successful development of the first truly non-toxic Fire Retardant (FR) epoxy

We have tested this epoxy on various layers of basalt volcanic rock fiber fabrics and fiberglass and carbon fibers. All successfully. Typically most so-called FR resins give off toxic smoke that is more dangerous than the fire. This new FR epoxy builds up a char layer, sort of like an in tumescent paint, and prevents fire from penetrating to the lower layers of cloth and resin while maintaining great structural capacity.... Our chemistry wets out beautifully on most all fiber fabrics. Basalt is, for an FR solution, the prime material.

[cRiPpLe_rOoStEr]

Fire retardant is not fireproof at all. Well, considering the char layer may eventually get washed away or eventually become flammable, I'd still look at those ceramic compounds currently used on carbon-ceramic aircraft disc brakes. Makes me wonder how basalt could fare on aircraft disc brakes...