Hello board builders and repairers. I'm after a versatile laminating epoxy to use for a range of projects, including wanting to laminate boards that won't be painted. Are the so-called UV stable resins really up to the task yet? How do they go for filler and sanding/finishing coats?

Here are my priorities. What experiences have you had with relevant products? Thanks!

UV Stable - will retain strength and clarity for clear laminations including over timber.
Minimally Toxic - I've had enough chemical exposure for one lifetime (no more polyester!) and the planet hardly needs more dodgy gunk.
Decent Shelf Life - or available in smallish quantities (1litre or even 500mL) as there are only occasional projects.

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djdojo said..
Hello board builders and repairers. I'm after a versatile laminating epoxy to use for a range of projects, including wanting to laminate boards that won't be painted. Are the so-called UV stable resins really up to the task yet? How do they go for filler and sanding/finishing coats?

Here are my priorities. What experiences have you had with relevant products? Thanks!

UV Stable - will retain strength and clarity for clear laminations including over timber.
Minimally Toxic - I've had enough chemical exposure for one lifetime (no more polyester!) and the planet hardly needs more dodgy gunk.
Decent Shelf Life - or available in smallish quantities (1litre or even 500mL) as there are only occasional projects.

I have used (and still do) West System and Kinetix.

West tend to get yellow rather quickly. I was told that they have a product that have a good UV stability but not sure which one it is. I use resin 105 with slow hardener 206.

Kinetix has a better UV stability and is a bit cheaper as well. It has been designed for surfboards so I guess it would be a good option for your intended use.

When I mix small amounts of resin I prefer using syringes however Kinetix resin is so thick that I can't even pull the syringe... For small amounts I go with West System.

www.currumbinwoodworks.com.au/wooden-surfboards/

I think this guy use Kinetix and judging from the result it seems pretty good on wood....

Entropy Super SAP has good reviews amongst the people building wooden boards as well but I haven't tried this one yet.

Had good success with Kinetix R240. Go with the 126 hardener, the 160/161 is too slow and seems to be prone to bubbles in laminates. The West 105 is fine for board projects, but the Kinetix cures a bit harder, so better for high strength, like hydrofoils. Kinetix can also be post cured to get higher strength/stiffness (possibly West can as well).

Sanding coat - mix with microballoons, no problem. Hot coat - straight epoxy.

I have very limited experience with repairs and recently asked for some similar advice. I had boatcoat recommended by a few in the know which I went with and was very pleased with the end result. I repaired a couple of small chips to the trailing edge of a epoxy foil front wing and it worked a treat. They have small quantities available here..

boatcraft.com.au/Shop/

I have used both West Systems and kinetix, the Kinetix is more user friendly, and good for repairs. I found all epoxy resins go yellow to a degree, some builders add some white pigment to make it translucent. in terms of toxicity, I'm not sure which takes the cake, epoxy is highly cancerous, just doesn't stink as much as polyester

Entropy Super Sap CLR Resin (from Surfing Green in QLD). Yes, it is up to the task and did not yellow at all. Using my DIY TT 99% of time.
Filler *might* go cloudy in any epoxy.

West is old system, it is proved, but lacking modern UV protection, post curing etc. I use 207 hardener which is ultra clear.

West 207:

kiteforum.com/download/file.php?id=69198&mode=view


Entropy (did a mat finish):

www.kiteforum.com/download/file.php?id=64978&mode=view

djdojo....didnt you post about copying a tomo board? what are you useing to recreate the MPH ? are you going to mold it then make a block from the mold and wrap in sandpaper or something? or are you going to be meticulously sitting there with your cals transfering the height sover n over again? where you pulling your stencils from?

^^^ Not me doing the tomo, I'm just modifying an old surfboard and thinking about some pawlonia projects.

I use west system for no other reason than that's what my local boat builder buddy uses. It does yellow off but that doesn't affect performance. I have boards dating back past 2006 that are still going stong after extensive use.

I have always used West but it has a low ratio of solids (ie: lots of solvents). I still use it as it is avail everywhere and I want good flow into a couple of vac bagged things I make, that a thicker resin may not like...

If I was building a board as you said with pawlonia, a perfectly clear resin is not essential as the wood has colour. But yellowing later due to UV will be noticeable. West will yellow, so I'd go the Botecote "non yellowing" epoxy kit I use it for re-grip on boards that will see a LOT of sun and it is tops. :) Plus it is Aussie and can be posted non dangerous goods so if u r in a remote area it won't break the bank.

If you want premium gloss then try the stuff any surfboard guy is using, most look slightly blue in the resin and clear hardener. Will be a smidge more glossy but doubt you will tell the difference from the Botecote when it is 0.2mm thick over wood. How it looks after full sun after many years I dunno..... at least Botecote non yellowing epoxy doesn't have an issue

As for shelf life, both West and Botecote are avail in 0.5L kits and I have stored both in a hot as hell workshop fore 2yrs plus, with no problems. Or just make your board and paint it. Done.

Thanks for suggestions all. Just recovered this from another thread -

This CET epoxy is awesome. www.bennettfoamaustralia.com John Gillis from CET Technology; who pioneered shaping machines, epoxy sandwich construction in windsurfers and is now on the Sunshine Coast developed it..... and has passed on the formulas to Barry Bennett and Dion Chemicals...

So there are several options. Still happy to hear more experiences with different resins in different applications.

Paulownia ? They only use that timber because its "farmed" its not actually good or anything. Just grows quick. Its also what they use for bed slats and basicly EVERYTHING. So dont get to excited thinking its a great bita timber you probably have better stuff in your back yard

^

All TT are made of Paulownia. Plus Paipos, hollow surfboards, etc...Are you suggesting a pine is better? Jarrah? Cedar?


That is like saying a foam is no good for anything :)


DJ, non so toxic epoxy, only Entropy is BIO epoxy.

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dbabicwa said..
^

All TT are made of Paulownia. Plus Paipos, hollow surfboards, etc...Are you suggesting a pine is better? Jarrah? Cedar?


That is like saying a foam is no good for anything :)


DJ, non so toxic epoxy, only Entropy is BIO epoxy.

yeah he just said everything was made from it. then he said bed slats... so i checked that our for you

www.alibaba.com/product-detail/paulownia-drawer-sides-and-backs-board_60380103218.html?spm=a2700.7724838.0.0.nLCsiU

sounds ritzy

www.alibaba.com/trade/search?fsb=y&IndexArea=product_en&CatId=&SearchText=paulownia+wood+price

.... think im going to go to the dump and make some boards out of old beds and drawers

They all get you high.

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sir ROWDY said...
They all get you high.

Long haired lay about tweak

I have been making bamboo surfboards and found this stuff, so far so good.

It comes clear and doesn't seem to yellow? Find CET and Kinetix have a tint in it so turns my bamboo a different colour when this doesn't?

www.sanded.com.au/collections/surfboard-resins/products/surfset-flex-clear-3-litres

I'm on other side of the planet. Using Resin Research with fast hardener and additive F on last board and it's really good stuff. Used Easycomposites from UK and it was very similar, but have to deal with amine blush, easy enough to wash off with soap and water.
I have read most modern epoxy intended for lamination and coating is uv resistent. But I'm at 56N so uv is pretty minimal!

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Plummet said..
I use west system for no other reason than that's what my local boat builder buddy uses. It does yellow off but that doesn't affect performance. I have boards dating back past 2006 that are still going stong after extensive use.

What's the flex like in the resin Plums? Any cracking?

Great thread by the way peeps

Big price differences!

$85 for 3 litres www.sanded.com.au/collections/surfset-epoxy-resin/products/surfset-flex-clear-3-litres

$137 for 3 litres www.surfinggreen.com.au/product/entropy-super-sap-clr/

Thoughts on this?

$137 + $15 for dangerous goods + postage

You're still looking for Minimally Toxic, are you? :)

^^^ Yes, and whilst the super sap seems to be made from more sustainable materials, they don't say anything on the web page about its relative toxicity to the end user. I've had a look at the MSDS. I don't really know how to decipher it but seems it's still fairly nasty. Anyone with more knowledge of translating MSDS into layman's terms, that would be very helpful.

The surfset says it's xylene free, but I couldn't find a link to the MSDS to do a comparison.

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djdojo said..
Big price differences!

$85 for 3 litres www.sanded.com.au/collections/surfset-epoxy-resin/products/surfset-flex-clear-3-litres

$137 for 3 litres www.surfinggreen.com.au/product/entropy-super-sap-clr/

Thoughts on this?

dbabicwa said..
$137 + $15 for dangerous goods + postage

You're still looking for Minimally Toxic, are you? :)

Maybe Surfset is Australian made? Entropy made in USA?

Just Looked at MSDS paperwork, the only major nasty I can see in the Flex is Alcohol used instead of Xylene as a solvent? But maybe I'm reading the MSDS wrong?

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Loftywinds said...

Plummet said..
I use west system for no other reason than that's what my local boat builder buddy uses. It does yellow off but that doesn't affect performance. I have boards dating back past 2006 that are still going stong after extensive use.

What's the flex like in the resin Plums? Any cracking?

Great thread by the way peeps

No cracking other than on the topcoat of one landboard which I applied a coat too thick. Oh yeah that landboard is designed to flex 130mm of hard hits. So it has a lot of movement on that skin.

That means will scratch more easily than Entropy, and is more flexible. Something to consider when building ie a foil:)


Easy test: with 260-300 grit wet sanding West will sand off, Super SAP will be untouched.

I just got SAP 3L yesterday, and can compare a leftover hardener with almost 2years old one. West hardener will definitely change over time (got fast, slow and ultra clear, all different colors). Which is a bugger when doing a board, and you decide to go with different hardener - resulting in different color :(

West odour is bad, again, depending on hardener. SAP odour is not noticeable.

I would be really surprised with epoxy containing acrylic and no heavy smell. Try sanding some acrylic, says it all.

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dbabicwa said..
That means will scratch more easily than Entropy, and is more flexible. Something to consider when building ie a foil:)


Easy test: with 260-300 grit wet sanding West will sand off, Super SAP will be untouched.

I just got SAP 3L yesterday, and can compare a leftover hardener with almost 2years old one. West hardener will definitely change over time (got fast, slow and ultra clear, all different colors). Which is a bugger when doing a board, and you decide to go with different hardener - resulting in different color :(

West odour is bad, again, depending on hardener. SAP odour is not noticeable.

I would be really surprised with epoxy containing acrylic and no heavy smell. Try sanding some acrylic, says it all.

Just Googled and saw you are talking about our product! Thanks!

Epoxy/Acrylic is new to board building but not in composites, The main thing it does is makes it hard -wearing in our mix it is mainly epoxy but the acrylic helps with UV stable - and more scratch resistant.

The smell - no different to SAP or any other new tech Epoxy. The guys in the lab and making our product in the factory (made in the Central Coast NSW) don't use masks - it is an open area that has the right ventilation but I would say if you are building in a garage taking precautions with safety is the right thing to do. As per all epoxies you need to cover your skin and sanding I would suggest to make sure you use the right mask to sand.

We decided that we would talk about the differences in our epoxy - no xylene most surf epoxies have this, acrylic for harder wearing/ UV stable.

Sanding - you sand the same way you sand any epoxy, How our product works is that the epoxy part goes off first and then the Acrylic hardens up which makes it easier to sand in the first 1-4 days and then after that its pretty much the same sanding as any other epoxy. But this means you don't need to add the additives that the other companies recommend to make it easier to sand.

Other great thing is that you can get a Gloss coat. Get a lot of industry guys shocked that you can do it with epoxy.

We have more and more users jumping onto our products everyday.