Chicken wire between fiberglass layers??

[canadian_cowboy]

Is it a good idea/ possible to use plastic chicken wire/snow fencing between layers of fiberglass for strength??

Rob

[mmd]

Possible? Yes.
A good idea? No.

[canadian_cowboy]

Hi,
Thanks for the straightforward answer. P.S. I was living in Bridgewater last year and went to Park View Ed. Ctr. for grade 11, heard of it??
Thanks again for the heads up.
Rob

[DaveB]

Hi,

Interesting, but I agree that it might not be the best idea... not too sure of myself though as I don't have piles of experience (yet.... )

I think that one of the real benefits of frp is that it doesn't rot or rust... I think that chickenwire might, and there might also be some bonding issues... maybe even thermal expansion/contraction issues...

Does anyone else have any other ideas on the topic?

Cheers,

Dave

[ErikG]

An FRP laminate should be an engineered composite. Using a material with unknown properties in it seems like a petty bad idea

In any case, since it appears to be plastic it wont increase he strength of any laminate as glass is almost surtainly a lot stronger.

As has been said... A really bad idea

[Bhatla]

Some years back, I as involved in vibration testing of FRP cases for portable military equipment.

One of the batches tested had copper mesh layered in between the FRP. Endurance ( Heat cycling and vibration) tests revealed separation of the layers at the metal mesh. We suspect de-lamination occured due to to poor bonding between the copper and FRP, or thermal expansion issues.

Mechanical testing show no appreciable advantage in flex strength/weight ratio. In an hammer impact test, the metal meshed FRP fared worse than the batch with no metal.
The "dent"was permanent.No signs of recovery.

Cannot say if the same would be true of a plastic mesh. I would firstly suspect bonding, epoxy and most plastics do not bond well.

As ErikG points out, this is hi tech engineering...

One suggestion , if you have access to a mechanical laboratory, say in your local college, you can make small samples and do some testing. I reckon all this will cost , is a few crates of the local brew !!!!

Hope above helps.

Prasad Bhatla

[mmd]

Rob, I live about three kilometres from Parkview, away from town. Just up the hill past the Cookville bridge, on the same side of the river as PVEC.

DaveB, where are you studying? Your 'Strength of Materials' courses will eventually explain (in more detail than you want) the answer to this question.

ErikG, you are on the right track - simplistically, the glass fibres resist tension in the matrix and the hardened resin resists compression; chicken wire and plastic snow fence don't have much tensile strength and, due to their large cross-sectional size, won't integrate into the matrix very well.

To be honest, and no insult intended, but considering these materials is so far "off the wall" that I find it somewhat difficult not to poke fun (good-naturedly, of course) at the question rather than to discuss it so reasonably. But then again, when FRP was new, developers tried all kinds of fibrous material, including sisal and cotton. And as the old saying goes; "There are no bad questions, only bad answers."

[Not A Guest]

plastic chicken wire/snow fencing core

glass/resin faces

Not worth my time to do the engineering, but if it bonds well it should be ok.

[Morgig]

Possibly slightly of track, but when I was at the JEC composite show in Pairs, I saw an interesting material on the Chomarat stand. It took the form of an open grid of large dia (1.0>mm) carbon rods, linked into an approximate 50mm square pattern. They were selling it as an alternative reinforcement in concrete. It got me thinking, that something along these lines would be an interesting way of stiffening a panel, without going for a full carbon mat.

[ClarkT]

One of our vendors recently brought by some woven bronze mesh with a coating to encourage proper bonding with vinylester. I believe this stuff would be useless as a structural reinforcement, but it might have some very intresting possibilities in building a ballistic reinforcement (bullet proofing). In ballistic panels, delamination absorbs the projectiles energy, so the fact that the metal mesh encourages delamination might be a good thing. I've not done any testing on it yet, but I'm curious if anyone else is thinking this way and has done any testing with this stuff.

[canadian_cowboy]

Thanks folks, definitely good to have some input from people who might know just a little about fibreglass where I know almost nothing and this will be my first project. I think I'm gonna go without the snow fencing for the fact that it'd make a pretty gaudy-looking surface in the fibreglass and also make it hard to paint and not easy to gel coat. Thanks again. Any more advice for a novice boatbuilder would be great my hotmail address is cowboy_9@hotmail.com or leave some here.

Rob

[PAR]

Since this is your first project, it would be wise not to venture very far from the path traveled by typical 'glass layup schedules. Why would you want to change the laminate with this stuff, which I think is PVC and will have bonding issues? I have to admit that the puns are rather tempting, but seeing the number of your posts and that you have been scared off the idea already has me biting my tongue.

After some experience you can do some testing with different types of materials in the matrix, but I think you'll find the R&D departments of the many manufactures have done their homework.

[canadian_cowboy]

Thanks for ALL the advice on my question. I'll likely have a lot more questions as I start getting into glassing and layering and sanding and painting and gel coating and even opinions on what color would look best on the hull design (same style hull as the original bluenose, only about 1/10 the size.)
Thanks again for allowing me to make all u experts laugh!
Rob, Cape Breton, NS