Here is my first attempt to fix a small 1.5" x 3" delam on the deck of my Goya Bolt as recommended by West Systems support. Note that the delam was due to an impact (dive knife plastic case) which compressed the EPS and then the deck sprang back to its original shape pulling away from the EPS.
Initially thought I could just make a cut in deck, insert syringe, and inject epoxy and push through to exit cut. But needed to make a small hole for syringe tip to get epoxy in (did not cut down syringe tip from stock West Systems syringe).
Couple of comments:
1) It took a lot of effort on syringe plunger to get epoxy to enter delam, but it went in and moved through it and then exited two small cuts I made in deck on each far end of delam.
2) Before injecting epoxy, when I pressed and released delam I could hear deck sticking and releasing from EPS (residual glue used to hold deck to EPS). After injecting epoxy could not hear the sticky sound.
3) Pushed delam deck to move epoxy around until it came out of two exit cuts.
4) Once delam area was filled with epoxy could NOT inject any more with syringe, just too much resistance using thumb/finger pressure.
5) Put soft foam over just delam area and then added weight to press deck down.
Will get back after it cures!, again this was a small delam area.
Used orange crayon to mark limits of delam, comes off with microfiber cloth and 70% isopropanol. West Systems syringe and mixing tip for SixTen epoxy cartrige.
Injecting epoxy into delam, really had to press plunger hard and make sure tip was not blocked by EPS, had at a very shallow angle (more than in picture).
Epoxy oozed out of all cuts, pushed on delam to move epoxy around inside delam to edges.
Probably 30 pounds of pavers sitting on soft foam that only covers delam. Covered delam and holes with Saran-wrap so epoxy oozing out would not get on foam.
Epoxy setup, so removed weights to check, delam is now solid with no flex, put weights back on and will leave on 24 hr just to be safe.
Three days of off gassing in the bathroom with the fan on and you'll be good to go .
Select to expand quoteHydrosurf said..
Not thickened epoxy?
610 is a thickened gap filling epoxy.
Select to expand quoteImax1 said..
Three days of off gassing in the bathroom with the fan on and you'll be good to go .
Very close!, when I touch up the two cuts and one hole with Rustoleum enamel paint it will off gas for 7 days in the bathroom with the fan on for the first day or two (have a variable speed switch for fan so can leave on low and not hear it outside the bathroom). Enamel also needs 7 days to cure before seeing water.
Oh, and the other thing is 610 does not get even warm while setting up, at least for the relatively thin layer required for the delam. I had read here somewhere that was a problem with epoxies, they can get so hot will melt the EPS. But West Systems support told me that only happens if the epoxy pools, but did not define "pool".
Good stuff. I think this is a good key hole surgery method for surf boards
. The only thing I would recommend is to form up the holes with blue tack to prevent epoxy spillage, and have a 2nd syringe to suck the access epoxy from these blue tack wells. If you destroy your lovely grippy deck around the pads, then you will have a new problem when you go to gybe/tack this board.
How much epoxy did you inject ?
When I first used injection method, I was worried about the thermal runway effect. So, as a test, I mixed various qualities of West System 105/206 in day time temperature of ~25C (eg 10ml, 20ml, 30ml etc). I heated each quality with a heat gun to ~70C for 5 minutes, then took heat away. I then monitored. I found that about 50ml (about 3cm deep in the silicon container I was using) it would go critical, so this gave me an idea of the quality not to approach. So I never inject anymore than 10ml of this 105/206 at once (a safety margin of 5 times less), and this has never given me an issue. I also do my repairs at night when the air temperature is dropping.
This threshold could be different for other brands/models. I have been using Eparency's ultra clear epoxy lately (a fantastic product !). I should probably perform this same test on this product before I start using it for key hole board repairs.
Select to expand quoteSandman1221 said..Imax1 said..
Three days of off gassing in the bathroom with the fan on and you'll be good to go .
Very close!, when I touch up the two cuts and one hole with Rustoleum enamel paint it will off gas for 7 days in the bathroom with the fan on for the first day or two (have a variable speed switch for fan so can leave on low and not hear it outside the bathroom). Enamel also needs 7 days to cure before seeing water.
Variable speed ....?.....why didn't you mention this before ?
Select to expand quoteImax1 said..Sandman1221 said..Imax1 said..
Three days of off gassing in the bathroom with the fan on and you'll be good to go .
Very close!, when I touch up the two cuts and one hole with Rustoleum enamel paint it will off gas for 7 days in the bathroom with the fan on for the first day or two (have a variable speed switch for fan so can leave on low and not hear it outside the bathroom). Enamel also needs 7 days to cure before seeing water.
Variable speed ....?.....why didn't you mention this before ?
That is on a strictly need-to-know basis, and you did not need to know until now.
Select to expand quoteImax1 said..Sandman1221 said..Imax1 said..
Three days of off gassing in the bathroom with the fan on and you'll be good to go .
Very close!, when I touch up the two cuts and one hole with Rustoleum enamel paint it will off gas for 7 days in the bathroom with the fan on for the first day or two (have a variable speed switch for fan so can leave on low and not hear it outside the bathroom). Enamel also needs 7 days to cure before seeing water.
Variable speed ....?.....why didn't you mention this before ?
If it sucks it sucks
Actually, the paint touchups I did are so small (used the end of chopstick wet with paint to touchup the cuts and small hole in deck) there is no need to put in bathroom while it cures. All done, no mess from oozing foam, and deck is now stronger than when new!
So there you have it, a relatively easy way to fix small delams due to impacts, versus the separation of the skin from the core due to manufacturing defects, age, or exposure to excessive heat and/or sun.
And have to say that deck is really thick, from cutting through it, and even though I stepped in that area many times the deck did not crack over the delam area. Francisco Goya really had the Bolt built tough.
Select to expand quotejn1 said..
Good stuff. I think this is a good key hole surgery method for surf boards. The only thing I would recommend is to form up the holes with blue tack to prevent epoxy spillage, and have a 2nd syringe to suck the access epoxy from these blue tack wells. If you destroy your lovely grippy deck around the pads, then you will have a new problem when you go to gybe/tack this board.
How much epoxy did you inject ?
When I first used injection method, I was worried about the thermal runway effect. So, as a test, I mixed various qualities of West System 105/206 in day time temperature of ~25C (eg 10ml, 20ml, 30ml etc). I heated each quality with a heat gun to ~70C for 5 minutes, then took heat away. I then monitored. I found that about 50ml (about 3cm deep in the silicon container I was using) it would go critical, so this gave me an idea of the quality not to approach. So I never inject anymore than 10ml of this 105/206 at once (a safety margin of 5 times less), and this has never given me an issue. I also do my repairs at night when the air temperature is dropping.
This threshold could be different for other brands/models. I have been using Eparency's ultra clear epoxy lately (a fantastic product !). I should probably perform this same test on this product before I start using it for key hole board repairs.
I wiped off the excess epoxy before putting weights on the deck (came off paint pretty clean), and no epoxy oozed out from the weights, 610 is a thickened epoxy and does not move easily. Deck is fine, and only step in that area when on the water.
I injected what you can see in the filled syringe picture, and of course some oozed out, so maybe 5 mL?
Good info on how thick epoxy needs to be to start an exothermic reaction, thanks jn1!
But what I just noticed is two very light lines in the repaired deck "under the white paint". I had painted that area of the deck with Rustoleum enamel paint to cover the black stripe. After being painted, the deck delaminated from the impact of my dive knife plastic case and I stepped on the delam regularly, was surprised how well the carbon deck stood up to the repeated flexing, and so put off repairing it. Well it turns out the carbon deck cracked in two places "under the white paint", fortunately the white paint did not crack, had also top coated white paint with several coats of clear enamel.
So if you notice a delam on the deck of a board repair asap, otherwise flexing of the delaminated deck could cause cracks to form and leak water inside the board.
Should have put it in the bathroom for seven days with the fan on , medium setting . If it's a four speed setting , it's a tricky one . You never really know if you should use setting two or three . And you won't know unless you try both .
Select to expand quoteImax1 said..
Should have put it in the bathroom for seven days with the fan on , medium setting . If it's a four speed setting , it's a tricky one . You never really know if you should use setting two or three . And you won't know unless you try both .
You are old school !, the bathroom wall light switch panel has two toggle switches, one for the lights (left-side) and the second for the fan (right-side), the fan ON/OFF toggle switch is about 3/4 the thickness of a regular light switch, and along its right-side is an infinitely adjustable slider for the fan speed 
Select to expand quoteImax1 said..
How the hell do you know the correct setting?
I stick my finger in side the vent and count how many times per minute the fan blade wacks my finger.
Have had the repaired Goya Bolt out now for two sessions and then carefully checked the repaired deck and it is still solid!
If it's survived two sessions it will probably now last a lifetime, maybe decades, that's what I find, failure will most probably happen in the first two sessions. Well done sandman.
Select to expand quoteSparky said..
If it's survived two sessions it will probably now last a lifetime, maybe decades, that's what I find, failure will most probably happen in the first two sessions. Well done sandman.
Good to hear, thanks Sparky
