I bought a diamond cruzader FSP pro in July. I did not hit the board I am not jumping. paint chipped very quickly. now 2 month after I see crack appearing on the rail of the board. I am in the east so temperature over 50 degres celsius are not rare in summer. it seems it did not pass the summer test. Gong board are tested in brittany where temperature barely go over 25degres in summer. not a surprise they not tesing it with higher temperature.

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colas said..

Sandee said..
Well, clearly white things reflect heat better than black things

No exactly. White things reflect the direct sunlight.

But when in an oven, i.e. a car whose internal air itself is hot, white wont protect the board: everything in the car not directly under the sunlight will end up at thermal equilibrium (same temp as the rest of the car), bag or no bag.

That's true. Maybe I should've said that the light colours better resist being heated by the sun, rather than "reflect heat", as the situation in a car or an oven is quite different from leaving a board in its bag in the sun.
Therefore the colour of the bag would make no difference, but some sort of thermal insulation foam would help to slow the time taken for the bag's contents to heat to thermal equilibrium.

MBA- rail crack has nothing to do with heat .. Unless heat caused a delamination and the rail is then taking more load so it cracks. have a good push on the deck and bottom to see

tiny rail cracks can be fatal very quick it they line up with the front of the tracks so if that's the case, have a reallllyyyyy good look on bottom for crease using oblique lighting

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mba75 said..
Gong board are tested in brittany where temperature barely go over 25degres in summer. not a surprise they not tesing it with higher temperature.

I am always flabbergasted on how people just invent "facts" out of thin air...Gong was for a long time based in Marseilles, then Corsica.
And nowadays, some team members live in the tropics.
And the team regularly tests gear in hot climates. (Currently in Tahiti, as you can see on their instagram/facebook)

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mba75 said..
I bought a diamond cruzader FSP pro in July. I did not hit the board I am not jumping. paint chipped very quickly. now 2 month after I see crack appearing on the rail of the board. I am in the east so temperature over 50 degres celsius are not rare in summer. it seems it did not pass the summer test. Gong board are tested in brittany where temperature barely go over 25degres in summer. not a surprise they not tesing it with higher temperature.

How does one wingfoil in 50 deg weather, let alone breathe?

"Out where the river broke
The bloodwood and the desert oak
Holden wrecks and boilin' diesels
Steam (foiling) in forty-five degrees"

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Hwy1North said..
How does one wingfoil in 50 deg weather, let alone breathe?

They don't.
Eastern Australia coasts never reached 50C.
"The highest temperature ever recorded in Australia is 50.7 ?C (123.3 ?F), which was recorded on 2 January 1960"...

en.wikipedia.org/wiki/List_of_extreme_temperatures_in_Australia

They should only sell boards where it's 10C to 20C? Or maybe it will be Isobars that will then be the problem?

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Hwy1North said..

Holden wrecks and boilin' diesels
Steam (foiling) in forty-five degrees"

I always though it was
Holden wrecks & boiling desires
scheme at 45 degrees

I think my next board's going to be wood

Sunny day here in Brisbane SEQ, a nice 27 c in shade. Just measured the temps inside my car that has been sitting outside, windows up.
Dash board, in full sun 77.1 c
Shaded area in back of car 51 c
Sunlit Area in back of car 59.3 c

More than enough to delam a board if the gortex vent is blocked which is usual if the board isn't new.

And this isn't even a hot day.

A lot to be said for well made boards and manual vent.
Yet threads about how good 3.5kg boards are, seem to have quite a few fans. Lots of reinventing the wheel with every new discipline only to find out the tried n tested constructions work.

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Mark _australia said..
MBA- rail crack has nothing to do with heat .. Unless heat caused a delamination and the rail is then taking more load so it cracks. have a good push on the deck and bottom to see

tiny rail cracks can be fatal very quick it they line up with the front of the tracks so if that's the case, have a reallllyyyyy good look on bottom for crease using oblique lighting

yes heat cause the delamination under the pad on the deck. I let sun resin dry an hour on the grass was enough to cause that delamination. It was invisible so I navigate with it then the crack appear. Now i wonder if I can ask a Local windsurf repairer to inject resine under the deck as the bottom of the board is still perfect. Gong did not suggest that solution they want me to pay for repair and buy another board So I wonder if somebody has experienced with that kind of repair?

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mba75 said..

Mark _australia said..
MBA- rail crack has nothing to do with heat .. Unless heat caused a delamination and the rail is then taking more load so it cracks. have a good push on the deck and bottom to see

tiny rail cracks can be fatal very quick it they line up with the front of the tracks so if that's the case, have a reallllyyyyy good look on bottom for crease using oblique lighting

yes heat cause the delamination under the pad on the deck. I let sun resin dry an hour on the grass was enough to cause that delamination. It was invisible so I navigate with it then the crack appear. Now i wonder if I can ask a Local windsurf repairer to inject resine under the deck as the bottom of the board is still perfect. Gong did not suggest that solution they want me to pay for repair and buy another board So I wonder if somebody has experienced with that kind of repair?

That almost never works. Usually it just makes things worse.

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mba75 said..
I let sun resin dry an hour on the grass was enough to cause that delamination.

[1] UV-curing resins need only 5mn in full sun

[2] I always protect the rest of the board (in the shade and for exposed parts white sheet or towel), to only let the UV resin in the sun.

You do not want to leave the whole board static in the sun because, first, obviously, it is a huge warranty-voiding risk of delamination (boards in action are cooled by the wind and water), or at least major shortening of its life expectancy, and second, you will be pushing air through the repair during curing, weakening it and creating bubble holes.

Question: are you speaking of a pad bubble (pad unglued) or a real delamination of the composite under the pad?

Injecting resin to fix the damage could be done, but it will be heavier, and it must be done properly (e.g. with the blank dried, taking care of the exothermia risk, ...). Competent repair shops will not attempt is, as the composite that has been lifted may have been structurally damaged: they remove the soft part and re-glass, which will be expensive for sandwich parts.

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jdfoils said..
That almost never works. Usually it just makes things worse.

There is more nuance that that statement suggests. Injection does work, but it is a last resort.

Injection has a lot of caveats:
1/ The failure may be excessive, thus no injection method is going to do anything useful
2/ The area will be prone to failure soon after due to the mismatch of stiffness between the various materials and the injected material
3/ Likely not get a good bond between the injected-material and the existing materials.
4/ warped layers due to incorrect injection
5/ uncured injected-material is typical
6/ wrong type of material is injected

A proper fix is really the best solution. But if you are in the middle of nowhere, or the board is already on its last legs, or no repairer is available or the repair is not cost-effective -> then it is a possible-solution.

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mba75 said..

Mark _australia said..
MBA- rail crack has nothing to do with heat .. Unless heat caused a delamination and the rail is then taking more load so it cracks. have a good push on the deck and bottom to see

tiny rail cracks can be fatal very quick it they line up with the front of the tracks so if that's the case, have a reallllyyyyy good look on bottom for crease using oblique lighting

yes heat cause the delamination under the pad on the deck. I let sun resin dry an hour on the grass was enough to cause that delamination. It was invisible so I navigate with it then the crack appear. Now i wonder if I can ask a Local windsurf repairer to inject resine under the deck as the bottom of the board is still perfect. Gong did not suggest that solution they want me to pay for repair and buy another board So I wonder if somebody has experienced with that kind of repair?

How'd you get on with it?

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mathew said..
Injection has a lot of caveats:

And not least:

7/ exothermia: too much resin pooled in one place (you cannot control where it will go, especially if the blank has collapsed and created holes), in a space enclosed into heat-isolating material ==> temperature increase by the curing which will melt the blank, and even start a fire.

Here is mild exothermia creating delamination during curing of a new board by a professionnal glasser:

www.instagram.com/reel/DMi-V7XB-k2/

"kazumasurfboardshawaii: Things an Epoxy Glasser have to deal with... We epoxy glassers get to babysit without getting payed??. In the time it takes me to wait and fix bubbles, I could have caught 18 waves.... Long video but shows what a Glasser has to deal with on a daily basis."

It demonstrates how glassed EPS boards are sensitive to heat.
Please do not leave them in the sun.

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colas said..

mathew said..
Injection has a lot of caveats:

And not least:

7/ exothermia: too much resin pooled in one place (you cannot control where it will go, especially if the blank has collapsed and created holes), in a space enclosed into heat-isolating material ==> temperature increase by the curing which will melt the blank, and even start a fire.

Here is mild exothermia creating delamination during curing of a new board by a professionnal glasser:

www.instagram.com/reel/DMi-V7XB-k2/

"kazumasurfboardshawaii: Things an Epoxy Glasser have to deal with... We epoxy glassers get to babysit without getting payed??. In the time it takes me to wait and fix bubbles, I could have caught 18 waves.... Long video but shows what a Glasser has to deal with on a daily basis."

It demonstrates how glassed EPS boards are sensitive to heat.
Please do not leave them in the sun.

I laminate in the afternoon, not the morning so the falling temperature causes the air inside the blank to contract, not expand. Or use vacuum.

^^^
agreed
that was just air coming out of blank not exotherm

surfboard industry clings to so many old things and this is so easy to get around

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Mark _australia said..
^^^
agreed
that was just air coming out of blank not exotherm

surfboard industry clings to so many old things and this is so easy to get around

Exothermia is just the fact that a chemical reaction creates heat, which is then called exothermic.
en.wikipedia.org/wiki/Exothermic_process

Even if it just 1C increase.

My point was that even with a small temperature increase, the air moving inside an EPS blank can cause issues.
And thus leaving a board in the sun, or injected epoxy pooling is a huge temperature increase.

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mba75 said..

Mark _australia said..
MBA- rail crack has nothing to do with heat .. Unless heat caused a delamination and the rail is then taking more load so it cracks. have a good push on the deck and bottom to see

tiny rail cracks can be fatal very quick it they line up with the front of the tracks so if that's the case, have a reallllyyyyy good look on bottom for crease using oblique lighting

yes heat cause the delamination under the pad on the deck. I let sun resin dry an hour on the grass was enough to cause that delamination. It was invisible so I navigate with it then the crack appear. Now i wonder if I can ask a Local windsurf repairer to inject resine under the deck as the bottom of the board is still perfect. Gong did not suggest that solution they want me to pay for repair and buy another board So I wonder if somebody has experienced with that kind of repair?

I had several old windsurfers where the foam aged and rumbled under rear foot so felt spongy and delaminated. Some suggested and Boardlady.com explained how to inject 2- part polyurethane foam. That lasted a couple of years, and in one case it was then worth doing a redeck with fibre glass.

Yes, this seems like a Gong issue. I currently have 4 wing boards and only one the brand new Gong Cruzader Point has a ESP core issue. The issue that seems to be common is the EPS is melting away from the carbon inside skin. I know this as I have cut open the board and had a good look at what is going on. Im making a big statement here in saying they are possibly getting bad EPS from their China supply chain????It is interesting that the EPS that has become what looks to be melted away from the inside skin of the outer carbon foam shell, has a HDT consistent with the 100deg C as would be expected from EPS. I did a bit of a test to look at this sort of thing, also the contraction temp appears to be over the 120 dec C mark. The test spot I did however was not where the foam was melted away from the skin if the board. So there could be some inconsistency in the material.

It is always entraining to read some peoples theories about heat/sunexposure and composites. For a good read have a look at the article "why some dark boats blister" in professional boat builder number 64. This was one of my first reference articles that I used when running a composite R&D lab. Id love to show pics of the board and put in the link to the article but Im a newbie to this site so I cant.....

I left a slingshot board in the car without backing out the vent plug and it popped a section of the bottom. Not sure why all boards with light eps cores do not have gore vents, but lesson learned.

The fix was ten 1mm holes drilled with epoxy injected using a syringe then put into a vacuum bag. 2 months in and still good. I initially was hesitant to put all of the holes in the board, but exotherm from pooling epoxy is no joke. My other option could have added epoxy with a few holes and a vacuum placed a few feet away in another hole to pull the epoxy like an infusion, but I wasn't confident that it would work.

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sbpoint said..
I initially was hesitant to put all of the holes in the board, but exotherm from pooling epoxy is no joke.

So true.Plus letting your board in a windowed car in the sun is playing Russian Roulette:

All your pals telling your : "no worry mate, I have done it" will be of little comfort if you end up unlucky...

Sail247 - I see EPS melt and thus pull away from the skin all the time. That's not a Gong thing.
its not an EPS thing - they all melt at same temp. Crap foam may have inconsistent bead to bead adhesion and I have encountered that, our manufacturer quickly fixed it.