Not sure Epoxy 's better...

Hi everyone. 14 years with the classic PU/PE combo, i decided a few weeks ago to try the epoxy. So many hours spent on Swaylock’s reading “every” epoxy post… i thought i was ready to experiment! A month ago i shaped and glassed 2 shortboards with the Keahana kit (EPS/ Epoxy) but didn’t like the shaping step with the EPS. So i keep on exerimenting with the combo PU/Epoxy. My goal is all about performance: light and strong. I ordered some RR 2000 epoxy, shaped 2 boards (Eskimo surfblanks) and voila. (I know i should laminate with the RR KK or RR CE but it’s not available in France yet.) Painted the board all white (UV “protection”) and some acylic colors on the deck. 31° C (85°F i guess) during all the process, 2/1 resin/hardener, additive F 1% when laminating, 3% glassing, clean squeege, etc… I think i respect all the steps and tips.

First of all i was surprised how easy it went. Not so different from the PE (except the odor and the aceton free (good!), due to the temp it went really fast and did the 2 boards on the same day: entire lamination and deck glassing. I used 4 oz E- cloth, 1 layer bottom and 2 layer deck+ patch on the back foot. It went ok, except that once it dried i get some “bumps” with the cloth on the deck. Did i mention that i wear gloves since shape is finished, so…? BUT, here is the real problem: the following day i did the bottom glassing and let it cure for 12 hours, and post cure it for 8h at 40°C. Went for the FCS installation and… my bottom was SOFT! Well not mine, …, my shortboards one! If i handle the board too firmly i get my fingerprints on it!!! I let the boards post cure longer but nothing more, the bottom is still really fragile. The deck is ok, i shaped the board from the bottom but i always shape this way and to compare with the PU/PE, same step, it’s way harder with the PU (on the bottom)!!! I don’t understand what went wrong. I don’t want to laminate with one more cloth, so i’m going to sand the entire board and glass it may be thicker than i planned on the b…I’ll post some pictures ASAP.

What went wrong? Epoxies are way harder than polyester… not convinced yet!

http://markissurfboards.blogspot.com/

 

salut la France, comment va?

it is what silly says first: do really good measuring

then, when you mix, do it good, like 100 counts.

Make sure to scrape the sides of the pot as well as the bottom.

Personally, i use empty 0.5Liter yaourt pots, PE Poly Ethyleen stuff. 

And, make sure the resin is somewhat warm, but you seem to have that covered at 31 C!! where are you located?

checked out your blog, good work on those boards [and posting them too]

Wouter

sounds like you fcuked up the hardener ratio. must be accurate to the gram. epoxy is generally lighter and a bit tougher although UV seems pretty good to me as well. i use both

yah, i think Silly nailed it...

that's a ratio issue. ammounts have to be EXACT...

it seems to me that my epoxy dings much less easily. no shatters or cracks after over 2 years of surfing.

I think of surfboard epoxies as being more flexible than poly, as in not as stiff and not as hard and not as brittle.   I get more dents out of epoxy but basically no delams or spider cracking.  Back when I was using vinylester laminations and poly finishes I used to see real fine surface cracking where the finish didn’t flex as much as the lamination.   The VE is more flexible than poly but less flexible than the surfboard epoxies.  Leastwise, that’s been the case FOR ME with the resins I’ve used.  

Like silly has said it is probably a ratio thing with the part A and part B.  One thing that I have noticed also is you need to mix the part A and B really well.  I use an attachment that goes on the end of an electric drill like this one

epoxy mixer

I just go real slow with it because if you go too fast you will cause bubbles and since RR is a thicker resin it is real tough to get the bubbles out. 

I also agree with what the above guys say about epoxy boards not being as brittle and they don’t get spider cracks and what not like PE does. 

Hope this bit of info helps solve your problem.

Mike

www.anayasurfboards.com

Make sure you stir well!!! I stir epoxy for at least 1-2 minutes, scraping the sides and bottom during, to ensure that the epoxy is mixed enough…I feel like this is one of the most common problems that occurs with epoxy.

i mix for 100 seconds. but your right epoxy isnt better its just another type of useful resin for building surfboards

Thanks everyone, it’s incredible how fast you can get some precious tips. “Merci a tous.” In fact, here is the way i proceed to mix the resin and hardener. Small and clean glasses, 1 for the resin and 1 for the hardener. 2 resin + 1 hardener. Brand new chopstick. Mix slowly and during 3 min, in fact i stop when i feel the mix becoming hot! Then i proceed the classic way with a brand new brush. I guess i couldn’t be more precise.

BTW, Wouter, i live in the French west Indies, in Martinica. Best surfing season ever! But it looks like this is true every where else in the world, huh? Merci el nino.

http://markissurfboards.blogspot.com/

For whatever its worth

heres my 2cts.....

when measuring I use the painters qt containers with the markings on the side for ounces pints quarts, I dont weigh the stuff just eyeball it to the apropiate marks, first the resin then add the hardner

mix for 3 to 5 minutes, scrapeing sides and bottom

pour most of it out on the board and do the dance

never have problems with the larger amounts

only once when I eyeballed a little  like 3 or 4 ounces, that didnt fly

too much hardner makes for a soft cure, never gets real hard

I put the hardner in the cup first and swish it around the sides then add the resin and mix. It keeps the resin from sticking to the side of the cup and makes it a lot easier to mix.

Same here… hardener first. Not only does it prevent the resin from sticking to the sides/bottom, you can see the surface of the hardener rise (the resin tends to flow to the bottom, through the hardener, so the hardener “floats” on top) more clearly for a more accurate measurement if you’re going by volume.

What density is the foam?  It might just be a case of not enough glass if you're using light weight foam.

Great tip from Wood ogre & NJ surfer… so simple!

Eskimo core, density blue (regular). I switched to Eskimo when Surfoam shut down. Surfoam was the only French (and Euro when he started) foam supplier. Owner was Patrice Remoiville, well known glasser (Pukas, M. Cole, Linden,…). Some of these blanks where pure shit and others were just perfect with super strong and light foam. I was used to shape with these blanks and density was the same on the “shell” and inside. (Salut Patrice, si tu lis le message…) When i jumed to Eskimo, shaped the same way and get a lot of trouble: decks destroyed first month… Now i shape from the bottom, as i learn 14 years ago, and get less trouble with my boards.

Well, here is the end of the story: these 2 boards glassed with epoxy will never touch the water! 2 more weeks, more than 30 hours in the oven and… nothing more, they were still soft! Just watch the pictures. All that work, money, for that,… don’t want to read anything more about epoxies! Pictures on my blog.

http://markissurfboards.blogspot.com/

 




bummer! i can see how that would leave a bad taste in your mouth

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Well, here is the end of the story: these 2 boards glassed with epoxy will never touch the water! 2 more weeks, more than 30 hours in the oven and... nothing more, they were still soft! Just watch the pictures. All that work, money, for that,... don't want to read anything more about epoxies! Pictures on my blog.

http://markissurfboards.blogspot.com/

 

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Is Post Cure the problem? I think you over did it....too much heat...too fast...30 hours??? really ? 30 hours in the oven?

I use Resin Research. I do not post cure.......I glass in temps above 65f and cure for one week inside the house...Sanding makes heat....over sanding makes soft spots....

Resin Research Epoxy Resin is an Awesome product.....your problem is not the resin........................................

 

If it’s not tacky… just not hard… you can always add another layer of glass right over the first. That should have been the solution.

Too bad… Just don’t blame the epoxy. Sounds like user error to me.

If I quit everytime I made a simple mistake like this, I would have missed out on a whole lot of good surfing!

The product certainly is not defective when you consider the sheer number of people here and in production who use RR successfully day in and day out.

Chalk it up to a learning experience and be more careful how you measure your parts next time…but don’t throw the baby out with the bath water…that’s just ridiculous.