HELP PLEASE! How to deal with bubbles in 3" wide carbon tape on EPS??

I epoxied a 3" wide strip of carbon tape directly to sealed and painted (acrylic paint) EPS foam. The carbon tape runs from nose to the tail. The problem is that there are 4 bubbles in the carbon tape ranging in size from 3/8" to 1/2" in diameter. I could sand the bubbles away but doing so would mean sanding through the carbon strands and that would look funky. After I deal with these bubbles then I will laminate 2 layers of 4 oz S.


What’s the best way to lose the bubbles? Slit them with a razor > inject them with epoxy > put wax paper between the bubbles and maybe add some weights? It seems like it would be difficult to focus the weight on such small areas though. Or should I forget about weighing them down after injecting them with epoxy and then proceed with laying down the 2 layers of 4 oz S and deal with the slight high spots later when I sand the hot coat? (The ideal would and instant curing glue like a “super glue” that didn’t melt EPS and wouldn’t delam later.)

Any ideas will be greatly appreciated as I’d like to start glassing this board asap. :slight_smile:



With carbon it’s tricky to see if it’s well saturated or not… The ideal solution is to have a clean working table to fully saturate it, then roll it around a peace of PVC pipe and unroll it on the board afterwise.

In you case, i’ll sand it off, and do a “repair” with a smal carbon patch if you have some left.

The infusion of resin under it could be a solution but with a large needle. If you cut the bubble to lift it and apply resin under… it loose most of it’s strength so doing a “real” repair would be better.

W8 other advices sinces i’m unexperienced, but I went with the sand/small carbon patch way for my SUP were I had some bubble too.

Next time, i’ll definetly use a table to cleanly and carefully wet all the carbon cloth !


It seems like it might be tough to make a patch that’s small enough to match the surrounding threads but I’ll look over it to see if it’s feasible. You’re right about wetting it out on a flat table would have been better. It’s ironic that the reason for the bubbles is because I tried the flat table wet out method for the first time for the 4 oz S but the S started going off on me and I had to pull the whole mess up and throw it in the trash. (It was just too damn hot that night!) It was in the process of pulling off the 4 oz S that it yanked the carbon tape up in a few places resulting in the bubbles.

So there isn’t some super fast drying glue I could use that I could hold in place while it dried in a couple minutes?


Lam on table is funky and techy but failing to be really useful it’s a real waist of time. Next time put resin on board and lay resin on it, press it and add resin if needed. know make a real repair.

Lamming on the table would have gone okay if I had waited for cooler weather. I tried it because it’s amazing how little resin is used - which means less weight. (Only 36 grams of epoxy/hardner per lineal foot of board!)

Off the subject of this thread, but do you have any tips for laminating in 90 degree fahrenheit temps?



Lam when temp. is dropping not rising.

Keeps blank fron out-gassing.

If you see a bubble rising, open weave with a pin.

It will settle down flat.

Oops, double post.

Move along, there’s nothing to see here.

Stepping into it again, I know. If you think that a wet out table is a waste of time, then you probably need more practice, because you haven’t worked it out yet.  Reading between the lnes; sometimes to distract “competition”, some will post bad info.   Don’t believe everything you read on the internet.

EPS should always be primed an completely sealed before any glassing…end of story …you can’t seal EPS with a wet-out table…(lol)

For 1 or 2 layers of light open wave fiberglass on foam that need to be water tight i assume to say that table lam is a waist of time. For multi layers of tight exotic fibers vaccum bagged it’s an other question.
Seal EPS blank with resin before lam. Have enough resin mix to go fast and to not have to over work epoxy résine, go layer after layer in humid way.

hate to break the news to you, but if you are hand laying your fibercarbon glass…I would never consider buying a board from you.

Knowing your are probably not a vac bagger I will try to help you. 

  1. Why seperately glass the carbon 3" strip then the S glass ???

  2. Consider a poor mans vac bag technique by spraying a EPS compatable spray adhesive for the CF application

  3. CF is tached down with the adhesive, lay out the S glass and use a LOW VISCOSITY epoxy resin that ensures a optimal fiberglass abosorbtion and an every time it is tried tight lamination by hand. The filler coat will need to be NON low viscosity resin and the same with the final coat.

  4. Except for rail sections or tail patches, using CF and s glass without vac bagging techiques is a total waste of money. The tail patches and rail sections will even need an extra special technique for quality results. Anything else short of this is all smoke and mirror aesthetic BS.

  5. Unlike the CNC cutting machine versus hand shaping argument, Hand layed CF/S glass is functionally INFERIOR to vac bagged of the same materials.  Hope you hand shape only types aren’t short cutting in this quality arena. The responses have me thinking???




…that depends entirely on who’s holding the squeegee . I regularly see custom shapes in EPS totally laminated by hand with first class results . CF saturates very easily and presents no problem…problems always arise from badly prepared substrate ,or inexperienced laminators ----- and too many people blame the CF.

As other light fiber, fiber lighter or near same weight than resin, carbon want to float over resin so when you work by hand with resin over it can be difficult to not use too much resin. Vac bag allow to compact it on support. But be carreful to not be too dry a real bad thing for parts that work in flexural mode in sandwich config. The ideal ratio of 70% fiber 30% resin often mention abut composit is only for composit that work in tensil mode regardless gluing off this composit on something and need of eventual waterproofing.

Good question. Because I F’ed it up. My intentions were to glass the 3" carbon strip and then immediately do the 2 layers of 4 oz S. But because I tried the wet out table method with the S – on a night that was hotter than hell – the S went off soon after I started laying it on the foam and I had to peel the whole damn thing off and throw it in the trash.

I finally lammed the first layer last night with temps dropping. It’s the next morning as I write this and temps are rising, can I lam the second layer now with RISING temps since I already have 1 layer down? Or do I have to wait until tonight when the temps start falling again to lam the second layer of cloth?


toss the bitch in the trash.  If you can’t laminate epoxy with S or E or Warp or whatever…then you are doomed.  How in the hell did it kick right after you poured it on the cloth?   1) you kept it in the pot too long and it thermed out…right?  It wont therm if its thin…hell when epoxy is thin on the board, a fast kick is like 45 minutes or so?

Next time mix your epoxy…stir for about 1 minute or 2…then get it all out on the board, spread it out thin…all you need to do is have it touch the cloth. Then let it sit for a few minutes…let it saturate…go have a smoke, have a soda…whatever.  Now come back and laminate it down and pull off and residual epoxy.   I don’t care if its 100 degrees out…oops it 100 degrees here, and I just got done with a long board… it was fun, it kicked a bit slower than poly resin. But it didn’t therm on the board?..  WTF?  If you need more epoxy…just mix up a bit more.  

Carbon fiber is a resin rich matrial unless you vac bag.  it’s got that open weave that will take a huge hot coat unless you vac it flat.  Carbon fiber on a surfboard is over rated…ie, stiff, epoxy rich, etc.


Not a fan of carbonfiber on surfboards…ask me how I really feel?

I lammed one layer of S last night using the normal method (wet out on board) and the board looks great so of course I’m not going to “throw it in the trash.”

It worked last night in spite of the heat because I did it using multiple small 75 gram batches.

I did exactly what you said but in the 95 degree heat the cloth/resin started going off while I was still rolling it off the tube.

Anywho, the important question for the moment is…

Can I lam the second layer now during RISING temps since the 1 layer I lammed last night is down?

Nice board there Kayu. First class results mean alot of things but your beautiful board with a vac bag application would be superior functionally, structurally and time of build would be done in one day and ready to sand and polish the next day. Most high quality CF products are pressure cured for a reason. No reason not to pressure cure a CF laminated surfboard if you have the ability to do so.

The Joy of learning. Don’t give up!!!