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I've been googling around and although UHMWPE seems to be by far the most abrasion resistant I have been reading that Nylon is also extremely tough. I've been thinking about an approach and wanted to see if anyone had thoughts about whether it might work.

Dacron sailcloth (Rip-stop nylon) is really tough and seems pretty easy to get hold of. 2 problems are that its thin and epoxy doesn't bond to it well. According to google it melts at c. 270 degree Celcius. So I've been thinking of trying to make a bottom sheet out of it by heat bonding 3 or so layers of it. Domestic clothes irons may not be hot enough as it seems they only hit about 210 degress S on linen setting but a hot air gun would certainly do it.

I was thinking to use 3 layers of dacron and a layer of woven fibreglass. Heated to melting on a sheet of glass an pressed under another sheet of glass. The idea of the fibreglass is to create a better bonding surface with epoxy.

Alternatively I have read that hot glue melts at temperatures above the melting point of nylon and so has the potential to create a really good bond between layers of dacron.

Anyone tried something like this?

i'm a bit confused.
what is the intended function of the nylon or dacron cloth?
where on the board do you intend to use it?

nylon is tough (moderately strong for a thermo-plastic with good elongation), but difficult to bond.
dacron (one flavor of polyester) is a bit stronger and maybe slightly easier to bond to.

folks typically use UHMWPE or polyurethane as trim along the rails for ding resistance and because many want to avoid the extra effort in wraping the rails with glass.
but if you plan to add a layer of glass anyway, it seems like you're already doing the extra work w/o any getting any benefits.

neither nylon or dacron is stong enough or stiff enough to be a legit replacement for glass laminate in the boards layup (imho), so it would be mostly extra weight beneath the glass.

some folks have use formica as as a cosmetic top/bottom sheet in the lay-up.
still heavier and not as strong as glass but it is fast and easy with no sanding required.

regards,
-bill

zfennell wrote:i'm a bit confused.
what is the intended function of the nylon or dacron cloth?
where on the board do you intend to use it?

neither nylon or dacron is stong enough or stiff enough to be a legit replacement for glass in the boards layup (imho)

If I understand Mattma correctly, he would use it for bottom sheet for abrasion resistance.
But I don't see any comparison between the materials he is thinking of changing.

UHMWPE is a plastic sheet, nylon and dacron come as a cloth, so in this case the most abrasion resistance would come from epoxy.
That's why I don't see no point of doing an extra mile and by the way risking fast delamination.

If it would be possible to apply it to the glass with the iron, I would say go for it and report, how it goes , but with hot air gun??? Think about how many rincles will you get and holes in the cloth.

At least I would suggest you do a small sample, to trie all this ''new technology'' and what kind of abrasion resistance you get!

Thanks for taking time to think about the idea. I think I haven't been very clear on what I've got in mind so let me have another crack at it.

I can't source any of the usual abrasion resistant materials here in Australia (UHMW or PBT) and so I'm looking for alternative materials for abrasion resistance (not as reinforcement material).

I was talking to a local plastic supplier and seen some things on google the suggest nylon sheets material is the next best thing because of it abrasion resistance. While our local suppleir does sell nylon sheet in the right thickness, to get it laser etched so that it can be bonded to doubles the price and so prices it out of the game for me.

So I was thinking, what it we got woven nylon material and basically melted and pressed multiple layers of the material into a single sheet to use for abrasion resistance. Nylon is ease to melt and so my idea was to put 3 layers of nylon sailcloth together, heat them up past melting point and squeeze them together under high pressure (maybe through a roller). Add to this on one side some woven fibre-glass to create a face that will improve the (mechanical) bonding. Ideally the result is a uniformly thin sheet of nylon with the pores closed (melted) and one side that would offer a good mechanical bond. This would all be done seperately to th laying the board up so it would go into the normal lay up cold.

I wouldn't be heat bonding the nylon to the board, the nylon stack would be set and cold before it went into the layup.

I hope this helps clear up what I'm on about.

Cheers

They don't stick with glue and will peel off. Mechanical bond is the only chance - something like melting in a very thin fleece of some kind. Kind of on to a loser for the homebuilder but if you think mechanical bond, not chemical you you could be onto something.

You should do test pieces whatever you do and try and rip them apart with your hands (delaminate them - then you will get an idea and not waste time building rubbish..

mattma wrote:........
So I was thinking, what it we got woven nylon material and basically melted and pressed multiple layers of the material into a single sheet to use for abrasion resistance. Nylon is ease to melt and so my idea was to put 3 layers of nylon sailcloth together, heat them up past melting point and squeeze them together under high pressure (maybe through a roller). Add to this on one side some woven fibre-glass to create a face that will improve the (mechanical) bonding. Ideally the result is a uniformly thin sheet of nylon with the pores closed (melted) and one side that would offer a good mechanical bond. This would all be done seperately to th laying the board up so it would go into the normal lay up cold.

I wouldn't be heat bonding the nylon to the board, the nylon stack would be set and cold before it went into the layup.

I hope this helps clear up what I'm on about.

Cheers

yikes!
i get it.
I'm the last person that should be trying to talk someone out of a "science project" so i won't try here.
But let me add my vote to the growing list of folks that suggest trying this out on a smaller scale before you commit to a lot of time and tears.

Before you give up on bonding nylon sheet stock directly, you may want to consider another experiment.
There are many references to 'flame treating' nylon that has been shown to improve bond strength.
it is easy and has worked for me, but i still dont understand the mechanism well enough to sort out the magic requirements from the part thats just voodoo.

also, desipte the fact that i an a big fan of epoxy and generally resist adding too many ingredients to the mix.... I do have a fair amount of experience with something called Plastic Welder II as an adhesive for bonding Nylon. Its some sort of acryllic advesive. With good surface prep and their primer you can get bonds in excess of 1000 psi shear ( i think) that were always better than comparable epoxy bonds to Nylon.
1000 psi should be good enough for a thin sacrificial layer on the bottom of a board.
especialy considering how many square inches are involved.
on the other hand, a few coats of paint from time to time works well too.
its only water we're dealing with.

no worries.
regards,
-bill

Hi Bill

Thanks for the tip on Plastic Weld II. I have a look and see it I can find some locally.

Unforetunately our local conditions means that we do a good job of grinding the bottom surface on sand and rocks. Rails and sliders are currently a no go too.

I've used flame treating on ABS plastic for the rails and it does seem to work well. My reservation about it for thinner films is that the difficulty of making sure the nylon isn't burned through by the heat. I was thinking that heating it slowly with a hot air gun and pressing a layer of fibreglass into one side when it melted might act like the 'fleece / remay' longwhitecloud was refering and improve the mechanical bonding ( nylon heat joined to one side of it and then the epoxy bonding to the otherside.

I just came across a thread on skibuilder that talks about some of the approaches to controlling the heat treating process so will explore.

Anyhow, I have loads of nylon to work with in the form of dead kites so I'll post up anything thats comes out of tinkering with it.

Cheers
Matt

... in case anyone else finds this stuff interesting here is a link that has a detailed discussion of surface treatment approaches for improving bonding.

http://www.idspackaging.com/Common/Pape ... erview.htm

UHMW-PE (Dyneema) is also available as a corona threated fabric for composites too.
http://swiss-composite.ch/scs4/html/index.shtml?lang=en page 20.
Weighing only 0,97g/cm3 it is lighter than water and very high strength. It is an interesting composite material to try when building a bomb-proof board. I see two main disadvantages high price and low compresive strength. Using it for the bottom reinforcement and glass for the top would be cool. Relatively soft core material and resin system should be used to absorb the impacts well.
Coating Dyneema composite with a thick urethane multilayer topcoat would be relatively durable surface. Nevertheless it would fail on the rocks.
You should check snowboard construction http://www.snowboardmaterials.com/# not kiteboard...

I think no sailcloth material could be used for that purpose. The only way to go is a solid sheet of plastic. The cheapest material to try would be a glass protection film. It is thick enough.
http://www.3m.com/product/information/S ... -Film.html