Surfboard Delam repair Lumps and bumps !

Looking for a bit of advice, I am repairing a longboard that has delamed on the deck, I have cut away the damage and filled it with epoxy resin/q cell and have come to the tricky bit, The glassing ! I glassed the Delam with 4oz cloth and then 6 oz cloth over the top of that, I wrapped it round one of rails as the Delam was off center on the deck and decided this would give it strength, It seamed to go well and Glassed round the rail and onto the base of the board, I came back a few hours later and found that the resin had ran round from the deck and puddled just off from the rail on the base of the board, I am fast learning that resin has a mind of its own ! It was to late to smooth it out as it had started to cure, What is the best thing to do ? Do I just put it down to experience or is there a way I can sand it out ? It isn’t really providing strength and I could have probably wrapped less cloth round if I am honest but I am worried about Sanding down and cutting through the cloth and ending up with a worse situation than I have already, Any advice welcome for a newbie.
thanks Rosco

Can you post some pictures?

My guess is that you had too much resin so it could run off. Squeegee off the excess next time.

If the cloth is floating in the resin then the strength to weight is likely to be low (it will be weaker than a drier coating that is filled after it has dried). I was taught that you can lay two layers of cloth and then remove the top one while the resin is wet. That will remove excess resin and make the remaining layer quick to sand. Haven’t used the technique much.

I did a similar poor repair to a snapped board and just ended up cleaning it up and surfing it. Added a pound of weight but less effort than sand off and restart.

If you do sand your repair off/ when feathering in the edges of your repair, be careful of overheating the existing old cloth because that will bubble up and delam.

Here’s a pic of where the excess resin has ended up on the base just off from the rail, I think that is my concern @red_boards is the cloth floating in it or has it puddled above the cloth ? I might start with hand sanding it and see how I go.

That’s barely nothing. Sand it (carefully) off. Also, are those air bubbles trapped under the resin?

Thanks for the info, I will try hand sanding it and see how that goes,

 They aren’t air bubbles, It is an epoxy board and they are paint chips, I probably should have touched them up before I glassed it, I am not to worried about them though, Talking about air bubbles This is the delam area I have repaired, It is pretty big !  Looks like I have air bubbles here though or are they just where the resin has pushed the cloth up ? Do I need to do anything with them or will they be ok, They feel pretty solid when you tap on them.


Well,  you’re up in it to your neck eh?!  Those are bubbles yes. Is it your personal board? Leave the bubbles if you don’t care too much, is it for a well and respected customer or you want the best? Drill holes, fill the holes up with epoxy [and something in it perhaps] ON A DROPPING TEMP. EPS is a real pain to work with as far as temps go.

The mini drip is a matter of roughing up and filler coating the lamination you did over the yellow paint [which is likely to detach upon a localized impact…] 

Good luck

Hey Wouter, Yes It is my board, It is my old faithful Stewart Hydro Hull, I couldn’t bring myself to throw it in a skip, The base is sound so I thought why not give it a go at fixing it up, I am happy to leave the bubbles if they aren’t going to cause me any problems, I am going to try and give it a bit of a spray job so hopefully won’t see them but will leave that for another post ! 


Thanks for all your help guys 


It looks pretty good to me from here.  Always try to feather out the edges of a deconstruct/repair to avoid any hinge points.  I’m not sure if 4+6 Ozs of fiberglass is going to be enough to avoid future dents/delams.  If that is TufLite construction(Surftech?) there is a high density PVC sheet foam sandwich over a light weight EPS core.  I’m not sure what the equivalent fiberglass schedule is on that.  It’s always a good idea to at least try and match the strength of the original which in this case wasn’t enough to begin with.

Lumps and bumps?  Sandpaper is your friend!  


You used far too much resin when applying the glass. The idea is to use just enough to saturate the glass and adhere it to the board. On the other hand, you also have dry spots. Those may be due to depressions in the surface that were not even enough, or spots that absorbed more resin for some reason and it drained from the glass.  The ideal result is to wind up with the weave being very obvious on the surface and not have any puddles or pooling. It’s a balanace between too much (puddles) and too little (dry spots). It seems you got both.

Doesn’t look like a Tuflite. Those are always opaque colors with no visible foam and a PU paint finish. The Tuflites have four layers of glass in them. Not sure of the weight. See diagram

I definitely used to much resin, I would also spend more time prepping the Delam area as well next time and remove the bits of foam, It made it very tricky to fill, You can see them in the photo they are green, It might explain the dry spots as well, It has been a learning process for sure, Maybe I shouldn’t have gone for a epoxy Delam job as my first repair ! 

The fact that it’s epoxy means little. When it comes down to basics, resin is resin and glass is glass. Delams are tricky to repair and should be done by those with some experience. For instance, I probably wouldn’t have cut the glass away. You can fix a delam without removing any material.

I learnt a lot when I went from ding repair to laminating. Mainly how much you need to move the resin around over the cloth to get proper wet out and then to take the excess off.  Watch some laminating vids and you’ll see how the resin is moved to and fro to spread and penetrate and get the cloth down to the substrate.