600 GSM Biaxial Fiberglass

Meanz, as I posted earlier I've never used poly/nida core except for having worked on boats that incorperate it so have some experience of it, you may/might be able to laminate to it with stitched or woven using poly resin with success but check with the distributor to make sure, maybe the scrim stuff they put on it has special properties? but generally if using a core material such as foam or balsa an interface of either a minimum of 225gsm chop or a corebonding putty is required to meet Aus standards with poly/vinyle if stitched or woven fabric wieght exceeds 400gsm however if using epoxy, because of its superior adhesive properties the chop is not necesarily required.
Heres a rough comparison per ply with similar total fabric wieghts

Poly-
600gsm gelcoat
225 choppy
+560gsm resin
450gsm biax
+500gsm resin
700 gsm corebonding putty
200gsm coreprime resin
15mm h80 foam at 1200gsm
125gsm coreprime resin
225gsm choppy
+560gsm resin
450gsm biax
+500gsm resin
3-400gsm flowcoat
=6.5 kj per m2 less some waste & styrene emmissions(check my math-its been a long day!)

epoxy-
600gsm biax
+say 700 - 750gsm resin include coreprime
15mm h80 foam 1200gsm
600gsm biax
again say 700-750gsm resin
+ paint & fairing material
=3.9kg per m2 less a little waste but plus some paint & putty depending on finish etc

poly cons is 50% heavier & really stinks, pros are happens quick & includes coatings & "feels" more solid & includes a margin of thickness for fairing repairs
epoxy cons is "can" take longer esp' for coatings(carpet is good!) pros is lighter & dosn't attract complaints of so much stink.
A pretty basic comparison just to give you an idea of the materials, savings of wieght could be made on both by vac bagging etc & dropping the gelcoat on the poly model but then it needs paint or carpet & allowance can be made for fabric overlaps etc. Give your Nupol or FGI rep a call, personally I'd stck with a foam core but thats your call, just the foam is easier to proccess in regards to fixing some deck gear & creation of fastening annulus etc & its just more familiar to me. All the best from Jeff.

 

Meanz, those couta boats are a nice style of vessel, I'd love to have one myself, that nervous tick is from all that red & white lead paint & putty the old timers used, the "new timers" get it from xylyne & styrene & amides & acetonium & methlethle ketoniums & & & I think I got one right now just thinking about it, seeing as I'm a middle timer & might get it from both! I think they ban glass fiber from the couta boats to keep them special. Regards from jeff.

 

I love Couta Boats, Jeff, just saying they are the high tech builders around here & F/G is a dirty word in some quarters of the shed. I plan to have one in my stable of 50 or so boats

I think I'm going to use epoxy and probably Bote Cote, that way I can make up a filler, cut the core as originally planed (maybe 2:1, I will experiment) and fill it to give the edge some density. I can be sure it will be lighter and stronger that way and that everything will stick. Apparently you can fix straight through the polycore and just spread the load with large washers on the fixings. For the application I have its cheaper and stiffer than foam and I also have a fair idea what foam is about... this is part experiment as well. To tell the truth I am wondering if I even need to dress or seal the edge of this stuff and if I can't just laminate top and bottom and be done with it. Sounds a bit rough, but? When I have my hands on the stuff and have played with it a bit I will see what I think of it.

Thanks for the info Jeff...

Cheers

 

MBz

1. Decide on what your preference is for the surface finish, if paint then use epoxy, if gelcoat then use polyester.

2. You can use polyester resin and stitched glass with foam and tissue covered plastic honeycomb cores without choped strand mat as a tye layer.
But if your supplier recomends it then simply get a 400g DB with 200g CSM backing.

3. If you do not want to use foam then before you purchase Polycore check with what ever the new name for Huntsman Composites is for their version of plastic honeycomb core. A friend of mine was paying only half the cost of Polycore for the Huntsman product.

4. When you have prices for the glass, polyester, epoxy, foam and plastic core you can use attached spreadsheet to compare total cost of panels.

Cheers
Andrew

 

Thanks for that Andrew.

I will see if Huntsman Composites are in Australia, I have not run across them, only Nidaplast and thats about +20% on polycore.

Cheers
Mbz

 

MBz
Huntsman is now Nupol Composites and owned by the same parent company as FGI. phone 1300 786228 product is plascore.

I would also personaly have a bit more glass as the top laminate say 800g, but since you mentioned having carpet it may not be necessary.
The reason for this is that I have seen decks with 600g laminates end up full of heel dents.

Andrew

 

Hi Andrew... I'm just going from another guy I know of who did 600 top 400 bottom. Is that with polycore or foam? They said they jumped on the polycore from the cabin top with no ill effect! Thanks for the number I will follow it up, Nupol are the guys I'm buying the double bias from... funny they didn't mention it when I said I was using polycore.

Cheers
MBz