My epoxy longboard has become very heavy in the tail!

General Discussion
1

Hey guys,

I don’t know if any one can help but I am experiencing something that i have not come across before!

I am a sponsored longboarder and have been riding epoxy high performance boards for a few years now. The initial models I snapped very regularly but the latest model is fantastic and has lasted me a long time. I dinged the nose pretty badly a while back and packed it with solarez as i was abroad.

I have since fixed the ding properly and have noticed that lately the board has become very heavy in the tail. This is a very light performance board and it is so noticable during turns… My sponsors haven’t got any new boards for the next six weeks so i need this one to be performing up to scratch…

Do you think it might be waterlogged??? I have “dried” it out for the last 2 weeks and it still seems really imbalanced. Also the ding is on the nose and the board is always stored flat so why would the tail be heavy???

I have today stripped the repair out of the ding and cut back any damaged glass, the foam seems really dry and there is no discolouring around the ding!!!

Any advice will be greatfully received!!

2

Water intrusion through the fin box installation area? Maybe the force on the fin has wobbbled the box and cracked the resin allowing water to seep in. Very unlikely but it’s my best guess.

~Brian

www.greenlightsurfsupply.com

3

A few weeks ago I took one of my home shapes out for its maiden voyage. The first three or four rides were great. After a while I noticed that I was having a difficult time getting into the waves and the turns were more sluggish. Walking back to the car I noticed that the board was significantly heavier in the tail. Following a friends advice I laid it out in the sun and after a few minutes noticed water bubbling out through a pin sized hole near the tail. (I guess this says something about my glassing skills…) I would have never seen the hole if the water wasnt draining out of if.

Bottom line- Water can get into the EPS through even the tiniest holes that you might not notice with the naked eye. Check around the fin box or leash plug, these seem like likely places.

I widened the hole and left it in the car with the heater blasting for a few hours and it seemed to get most of the water out. Im going to give it a few more weeks to see if I can get any more water out and reglass the area.

Not sure if this helps…

4

drill hole in nose and tail, hook up clear plastic tube to tail hole(or the ding hole).

seal around the hole/tube entry point with mastic or bluetack perhaps

run tube into jar top and have another tube out jar top to vaccuum pump (jar is water trap)

turn on pump. leave for 4 hours

come back and it will be dry as a bone

the hole in the nose is to bring air circulation into it. fill hole after water removed

this is the only way that really works

5

Guys thanks very much for the great advice.

Upon closer inspection there is a postage stamp size area behind the tail grip that feels soft and I’m guessing has gone porous…

I have cut the glass from the area and am currently drying it in a warm room. After which I will try the vacuum pump.

Thanks again guys.

6

Thanks Silly, that looks like a good idea. I dont have a vacuum pump so would a shop vac work? Or wiil that be too much vacuum, not enough vacuum, or just plain fry the motor?

7

Do what silly said…water can’t exist in a vacuum…ET

8

i gotta do my board this week . i can post photos !. waves to good to get out

9

I get lots of waterlogged eps boards in for repair, and pumping out through small holes can take several days if not more for a longboard. Recently I’ve seen many dark colored boards that have leakage around the fin boxes and plugs. Often these will try and push out if the board becomes heated and the eps expands. When it contracts again, there’s noticeable gaps around the plugs and boxes allowing water to enter. After drying, I laminate cloth over the plugs/boxes and cut out the openings (fill if needed with modeling clay). I use several drying techniques, but the big question is if it’s really dry. You can put it in the sun with plastic food wrap over the openings and look for condensation. Better yet, weight the board when new, and weigh again when leakage is suspected. Most of the time the damaged area is big and open enough to just let sit for a couple of weeks and dry on it’s own. If not, I’ll bore a 1" hole about 1/4" deep and later plug it with polyfoam/gorilla glue and lam a patch over.

10

yeah thats why i know a vacuum pump works. i weigh my boards before and after. a pump will get you within a few grams

11

Hey Max,

In the past I’ve needed to fast-track the drying process for repairs to a sponsored riders’ sandwich board…As Silly has pointed out, a vac pump will assist the process. I add that it is possible to both blow AND suck water out of an EPS core simultaneously.

I can’t assume you are talking 1lb or 2lb…you don’t specify that your board is a sandwich composite or straight-out laminated EPS core, but it will be easier the lighter the foam is:- just as the lighter foams take in water more readily, so it is easier to get it out again, and there is no structural damage to the interior of the board. This is in contrast to PU in which water intrusion takes way longer, but removing it can mean stripping whole panels of glass.

I have used the existing vent hole as the blow point as well as a ding or hole drilled as the vacuum point. If your board is unvented, you will need to drill a hole in it and attach the compressed air outlet with a wad of plasticene, or some such stuff.

Attach a vac connection to a section of plastic sheet which is sealed with tape around the board at the ding or drilled area.

There is a critical and scary factor in attaching a compressed air nozzle to your board…DO NOT HAVE THE COMPRESSOR PRESSURE VERY HIGH !!!

Trust me I learned hard!

You can blow up your board. I did it to an all-time favourite of my brothers…There is a heart-breaking little pop sound as the skins are tron from the foam and the concaves become convexes!

The rule is:- BEFORE YOU ATTACH THE COMPRESSED AIR OUTLET, MAKE SURE IT IS POSSIBLE TO STOP UP THE FLOW OF AIR WITH YOUR TONGUE.

And I don’t mean you are trying to jam your tongue down the outlet ! If your compressor does not have a pressure regulator with a gauge, DO NOT GO THERE!

With pressure VERY gently forcing water towards the vac point, the drying time is reduced.

I prefer to rely on sunlight, gravity and evaporation. to drain water from a board, and the few times its been required, the board has returned to like-new.

There are no shortcuts in lamination of EPS…Pinholes are your enemy.

Josh

www.joshdowlingshape.com

12 
 Howzit silly,before you vacumn make sure you soak you soak the area wuth fresh water to get rid of the salt crystalls. the salt crytals ill cause delam the next time the predinged area gets hot or even heated uo up from up from sandingI have seen it happen and make pro ding repair guys cry .

I took my only 1 time to figure out what happened and the cause.Poly/ epoxy it doesnt matter and closed cell may be the only one not suceptible to it .Aloha,Kokua

13

Oooh did’nt know about that…I’ll remember that, good one Kokua.

Josh

14

Quality tip Kokua. Ill make sure I rinse the ding and re-dry it in the hot car before I glass it up.

15

great tip. thanks mike

16

Kokua’s absolutey right. On any damage, I take a spray bottle to rinse and then blow if out. On eps/epoxy, any water or salt crystals will cause pinholes as the epoxy exotherms on curing. On vac pumping out the water, make a separator as Silly suggests. If not, you’ll soon be needing a new pump.

17

heres a video of removing water

http://www.youtube.com/watch?v=Bk5UPMnBCsA

hey pete i need some vents whats your paypal

18

One important question that has not been discussed in this thread regarding the use of a vacuum pump to dry a surfboard is the ultimate pressure that one should not go below in order to avoid board implosion.

What experience do others have with safe operating pressures when pumping on a carbon fiber board?

Does fiberglass withstand less?

I’m thinking 7.35 psi or 0.5 atm is more than adequate vacuum to facilitate water removal.

19

Uhmmm- essentially, you're not trying to draw down the pressure inside the board, what you're trying to do is draw air through the board, which will bring any water with it. Just drawing the pressure down will get some of the water out, but by no means all. You'll get a little at, say. 0.5 ATM, but probably little more than half, but then you gotta release the pressure, which may even suck the water that remains further into the board and most certainly disperse it a lot more...not a good thing. ,

You want to make an air inlet upstream of both the vac pump and the area of water intrusion capable of letting in - well, call it a little less air than your pump is taking out. Hence the requests in this thread for the 'vents', usually placed up in the nose. Something the same as the ID ( inside diameter ) of your vac pump tubing should be fine.

 This is also an ideal place to introduce the fresh water that Kokua suggested to rinse out any dried salts that came in and which can most definitely have bad effects on the foam. Something like the laboratory squeeze bottles I remember fondly from chem lab would be ideal for that. Though the ones I swiped tended to have a very nice grade of ethanol in 'em.

Who says science ain't fun.

If somebody is really twisted, they could add a little food coloring to the water. Imagine the patterns it'd make. And you might just get a real good handle on where the water is coming in.

Hope that's of use

doc...

 

 

20

I’m hoping I won’t need this information anytime soon, but since I’m worried about a couple of areas of delamination on the underside of one rail on a handshaped epoxy longboard, I will ask.

Doc, are you suggesting introducing a little fresh water at the nose and pulling that water through the length of the board to flush out the salt? It’s hard for me to imagine intentionally introducing water under the skin, but then again I’ve never even used a vac pump.

Thanks.