PU with epoxy - shrinking problems

General Discussion
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Hi Paul, Thanks to everyone for input also.

O.K. so we are making toys to ride in the waves and sun but they can't be in the sun? This is wrong.

The heat capabilities of epoxy are very laking in my opinion. I thought it was superior to poly. This is not the case in this situation.

Sorry Greg I love your resin - can you please work on this and up the temp handling capabilites to match or surpass poly?

As far as I can tell this is the last hurdle. No poly board no matter how ravaged and brown ever did this - not ever.

A poly board can take way more heat and direct sun. This needs to be the case for epoxy also. It is silly to think that all of my customers no matter how many times you tell them will cover there boards.

I also feel bad telling them oh you can't leave it in the sun, car or heat. Board bags are a joke in hawaii. Here put your board in it's own sauna! Our island is big with beaches far apart - the boards are gonna heat up no matter what. It makes them think it's not durable - wich it isn't. Bastards are sensitive and need little sun umbrella's mounted on them instead of gopro cams!

One thing though is it doesn't happen to all of them so what gives?

I can only think sub par foam mixed with heat.

Guess I'll make some poly boards. Wife is gonna kill me cause the stink.

I attached a photo of a red epoxy RR KK with EPS SUP that takes heat very well. Thanks to PeteC's vents.

If it was PU would it vent or wrinkle? This guy leaves it on a truck rack in the direct sun for hours at a time. No problems in the first three months! No dents anywhere.

And by the way the KK resin is awesome. The pin holes that come from the rails draining out are no longer an issue. The KK fills the weave and stays instead of heating , thinning and then draining ever so little leaving a puka. I glassed this board one shot on the bottom with 6/6/4 and the top with 6/6/6 (two layups on the top) be fast for sure the bugga is 12'x36"x4.45 !!!

It is harder by far - the owner of this board is 250lbs and has never dented the deck.

Ah so much confusion and variables. I just can't have this happening - my home is Hilo and word gets around fast.

Thanks for helping out guy's. Mahalo's, Chris Upp

 

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Huie,

Everyone here is super stoked on the SB blanks we are getting.  I know you've been using them for sometime.  How have they been with epoxy and heat?  Any of these issues coming up?

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Nice Paul.  Some of the other posts seem to indicate some foam is worse than others.  As I stated before, we’ve npt seen this with Surfblanks but we haven’t seen it in US Foam urethane either until now.  Foam and resin do vary in temperature stability … all are somewhat different.  Also climate is an obvious variable.  We’ve also seen UV have this effect as well.  So I’ll make these suggestions.

  1. EPS is not at issue. No problems.

  2. CE and KK both contain UV blockers which will protect the foam from this type of damage from UV.

  3. As of this writing Surfblanks don’t seem to have this issue so this seems to be the safer bet.

  4. Higher densities will have less problems than lower densities. 

  5. As Paul suggested it appears that a post cure of 120F for 8 hours will help by raising HDT of the resin and would possibly help stabilize the foam as well.

  6. It should be suggested to the customer that they keep the board from being exposed to extreme heat.

In CA we are now only 3 years from the 2013 VOC mandates.  As suppliers to the surfboard industry we have that time to solve these issues if urethane is to continue to be part of surfboard building in the US.

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Wow! I am getting ready to do a stringerless high density [purple] surf blanks of america [pu]. I had planned to glass it with RR Blue  to try it over a high density pu  foam . It is going to be double 6 oz. both sides,but you guys are scaring me.any suggestions? Do I fair better with the high density foam [estim. 3 pound] that i will be using ?

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hi Greg , i have did a couple of bennets with resin research and they are still going strong after a year and a half . it is cooler here tho.  As Huie suggests it is most likely foam issues BUT huie does postcure his boards . his method is pretty low tech, as is mine . leave it on a even rack at the top of a warm shed for a day or two.

hey chris I hear you mate but realistically if you get a bit of foam or wood or whatever and leave it in the sun it breaks down just like our skin. a white polyurethane coating or gellcoat would be a good solution for UV but how many boards are you going to sell with that kinda finish. the fact of the matter is even tho we are a small business with very little income let alone profit and familys to look after and our workshops are landing zones for any bugger that wants to loan tools or materials, all our single surfy mates with disposable incomes think that we should be doing THEM a favour .

WHAT IS THE GO WITH THAT!

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btw chris some epoxys and polyesters have very high thermal ratings but this will effect workability and cosmetics. trying to achieve a balance . i think RR and some of the others achieve this for usability. i like RR but found it imposible to use in winter in my shed lol, but great to use in summer. if i had temerature control and better setup for post curings it would all be sweet. I think you will find a pu/epoxy combination that works but why not use eps . it seems like you guys get a good selection  of qaulity eps for cheap( something i dont have acces to ) . thats if you cant get hold of midgets foam. i cant get it here in New zealand. 

i think when you push for high thermal ratings then we are looking at more controlled postcures and different hardeners . as far as i can see you cant beat the flip times and cosmetics of gregs resin

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Very true - the resin is unbeatable. None better made in the world. Just convince the mates ( the ones who don't even return those tools they borrowed!) of that. The only reason I see a need for using the pu is for the ones who can't be swayed. Who wan't to ride what they call Clark foam kind brah! Most guy's think that it's the foam thats epoxy!

Who knows where I can get a surfblanks in hawaii?

Otherwise I have a huge block of very nice superfused eps like 12'x3'x3' and a hotwire. Oh fun smells.

Thanks to Paul, Greg and Huie for helping me figure this out. Maybe red formula is just not dense enough?

Much aloha, Chris

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[quote="$1"]

Very true - the resin is unbeatable. None better made in the world. Just convince the mates ( the ones who don't even return those tools they borrowed!) of that. The only reason I see a need for using the pu is for the ones who can't be swayed. Who wan't to ride what they call Clark foam kind brah! Most guy's think that it's the foam thats epoxy!

Who knows where I can get a surfblanks in hawaii?

Otherwise I have a huge block of very nice superfused eps like 12'x3'x3' and a hotwire. Oh fun smells.

Thanks to Paul, Greg and Huie for helping me figure this out. Maybe red formula is just not dense enough?

Much aloha, Chris

[/quote

 

Contact Derek Young at SB Hawaii in Waipahu 808-676-5050.  He can take some time to get back to you if he doesn't answer right away. 

You will also have to set up an account.  It can take a week or longer but he will ship on YB.  The Surfblanks America website has a downloadable blank catatlog and their rocker selection rivals US's one.

I wasn't completely sold on the talk about the blanks qualities, but it is for real.  You will trip out on how you can finish the foam.  It is very different than the US.  It is a hard foam, harder to overshape and easier to fine sand and tune.  The other plus is it doesn't absorb as much resin during laminating.  Kind of trippy, hard and light instead of hard and heavy.

 

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[quote=“$1”]

Huie,

Everyone here is super stoked on the SB blanks we are getting.  I know you’ve been using them for sometime.  How have they been with epoxy and heat?  Any of these issues coming up?

 

yea but i dont do large numbers   but i once lost about 50 boards to this same prblm no epoxy them days & it was clarke foam

i do know the reason for whats going on but would not be prepared to say anymore than that.

get to know your foam & leave the 2nd teir foam for  the suckers

 

in aus the main foam makers will give you 5 free blanks if you get this happening    and i have not seen or heard of it being a prblm with surfblanks over here

**as well midget has a special way to test his formulas so he knows any new formula is spot on before he sends  it out to his customers
**

**
**

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Thanks for the #. I will call up Derek and put some SB's to use. I have never shaped one.

Now i'm off to email us blanks and see what they have to say. Will let you guy's know what they say. Mahalo's

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Huie, why withhold information? This is a sharing site used for this discourse. There is no slander in stating the truth. Instead of baiting everyone, why not be forthright? Your experience and knowledge is well respected here even when it comes with a bit of piss.I realize you probably came across most of this info on your own and through trial and error, but somewhere along the way somebody has thrown you a “bone” two.I believe in paying dues as well but isn’t this the spirit of this site?

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You know I just could agree with this more.  Nice to hear someone say that paying customers shouldn’t be given team built.  I see it all the time … some novice with his new 4.5 lb shooter bustin the nose off on his first surf.  5.5 - 6 lb board and he’s got something of value that will last and it will make absolutely NO difference in his surfing. In fact in most cases it’ll go better.  Better momentum, better glide  … right on Huie

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if its the foam to blame, then why do these problems not show up on the same blanks glassed with polyester resin?

 

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[quote="$1"]

if its the foam to blame, then why do these problems not show up on the same blanks glassed with polyester resin?

 

[/quote]

 

Because its the resin.  The only one with problems with all resins was th Ice9 Cane blanks.

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remember, surfblanks aus is a different formula than surfblanks usa.  I found the aus to be better foam, lighter, whiter, stronger.  

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[quote=“$1”]

Huie, why withhold information? This is a sharing site used for this discourse. There is no slander in stating the truth. Instead of baiting everyone, why not be

    t b    i am more than happy to share .  you would be surprised how many i do help in some small way or another

forthright? Your experience and knowledge is well respected here even when it comes with a bit of piss.I realize you probably came across most of this info on your own and through trial and error, but somewhere along the way somebody has thrown you a “bone” two.I believe in paying dues as well but isn’t this the spirit of this site?

**when someone entrusts me with certain data its not in my make up to disclose it    sorry’’
**

**plus to post it up here it would only help another foam maker  **

**whith all respect have a nice day
**

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Huie, Understood and well stated. I wasn’t thinking about proprietary information nor was I taking it into account.Foam Makers have a right to their process. Your sharing of info in the past has helped me out and I’m grateful. Just thought a couple of your comments although pointed were somewhat cryptic. Thank you for the missive. Also I had a great day with a strong south running and respectfully, hope your day is equally nice. 

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I very much agree because if it were the resin the entire surface of the blank would be affected. Top and bottom. Not just certain places on it.