Alright here goes. I’ve built 6 SUP’s now, all EPS/RR epoxy/ 3x 6oz. deck 2x6oz. bottom. On 5 of these boards the rails look as if the hotcoat is either seperated from the glass or the rail lap have seperated from each other. The cloth pattern is visible. This has been from hits with paddles. Yea I know hits with paddles are going to ding the boards up. But I didn’t think it would do this so easily. My question is if I’m doing something wrong. I normally only build poly surfboards so epoxy is a learning curve for me especially SUP’s. My glass process is like this: I lam the bottom wetting out the glass and rapping the wetout cloth tight on the rails. Let cure to slight tackyness then flip and do the deck lam all in the same day. The next day I hit the deck lap with the grinder and do the hotcoat. I dont rough up the lam though since I do the hotcoat in the 24 hour mark. Hoping this isn’t the issue but quite certain its not. The board that doesn’t have this rail issue got the same treatment except when I was rapping the deck lap I hit the bottom lap with a resined brush to help with the rail wet out. All other steps the same, no rough up either before the hotcoat. Now this rail issue only on the rails. These boards have gotten pressure dents but it doesnt cause cloth pattern to show just dents. I’ve noticed that most SUP’s have painted rails. Is this the reason? Or am I making a mistake somewhere? Any help would be awesome. I hate the idea of selling SUP’s like this . If this is a common problem and is fixed with the paint to cover it up that would be a stress reliever. Thanks
i get the same problem the sup’s i have done for myself, i dont think its delam but im not sure exactly what is going on i would love to find out a fix though!.
Paddle hits show real bad on anything with color. I only do clear or white pigment on rail. It doesn’t show any paddle stress if you stay white.
Of course keep the resin use minimum on the rails to reduce chances of shatter spots. I assume you have 5 layers in rails. You should if you don’t
It’s possible that you have too many layers of wet cloth on the rails and you’re floating the cloth off the 1st rail wrap and/or resin is draining off the vertical rails due to so much wet epoxy. Even though it’s tracky, it will still flow to a certain degree. The more you load it up, the more it will flow. On race SUP’s with high vertical rails this is a real problem enough so that some are even set with the rails up. Try letting the 1st lam go off hard before doing the other side and see if this changes anything.
Paddle hits show more if the rails are not wrapped tight enough, I see less on SUP’s that are bagged. To minimize the effects, use carbon tape (bound edges) along the paddle area on the rail over the 1st lam, then cover it with the second lam. I’ve also seen the clear stick-on deck traction cut in strips and applied along the rails (the thin stuff, not traction pad material). Another preventative measure is to use plastic edging on the paddle blades.
Petec the rails only have four layers. To clarify the lam schedule its 1 layer deck patch that is about four inches from rail, then a layer cut at apex, then last layer rapping rail to bottom. The bottom is one layer cut at apex and layer rapping. So four total. I made sure I pulled out excess resin also. I could try with your idea of letting the bottom going to full cure next time and rough it up before deck lam. Like I said in my first post I didn’t rough up the rails before the hotcoat, could this be the culprit? Maybe its not getting a proper bond to the lam? I normally only have time for lamming the deck and bottom in the first day. Then I wake up in the morning to do the hotcoats.
I can’t say for sure what the issue is with your lamination. I think Pete’s advice is good though. Let it set up hard before the hot coat. The Graphite Tape along the rail is good as well. I’ve set up alot of SUP’s on Maui for surf schools. We always put rail tape along the rails to prevent scratches and shatters. I think we got ours from Surfco. I don’t think the rails on “Production” Sups out of Thailand and China are painted for any reason other than to cover up poor workmanship. Lowel
Don’t cut your laps short. SUPs need super tough rails. Not doing your customers any favors cutting laps short. All my layers full wraps. Still staggered edges, but as full as reasonable. Paddles and surfboards don’t mix well. like going surfing with a baseball bat.
This kevlar tape should help with impact resistance on the rails;
Might need to work more on the mechanical bond even though you’re doing the lam within the 24 hour window. All of these theories hold water and will probably help with this issue in the end. Good luck.
I know this post is old and I haven’t posted an update. Sorry to all the guys that commented for not getting back to you. Here’s my update on that issue I had back then. On my last SUP I took the advice Petec gave me and let the bottom lam cure hard and sanded it up the following day with 100 grit to rough up the weave so it would get a better mechanical bond as fiberglasshi stated. Then did the deck lam. All same schedule glass. What do ya know the problem was solved. Thanks all for the help. I haven’t made a SUP lately. What a bitch those things are to make. Exhausting. Heres a photo of my last one I did with the proper steps mentioned.
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Nice board! RR makes the 2020 resin for higher impacts and it is easier to wet out in the lam too.
Thanks lavarat will have to check that out.
Some fiber show most when ding, depend of sizing. Hexcel TF970 clear is far better than aerialite on this aspect.
Unfortunately from my experience, unless you can do your deck and hull at the same time and in so doing have both laps go off at the same time (within the data sheet gel time and so creating a real chemical bond) there are too many factory that effect the bond post gel time. As such if you want bulletproof rails on a EPS sup without bagging deck and hull in one go, you need to let the rail cure enough to sand to creat a strong mechanical bond between that hull lap and the deck lap. I run a “cheater coat” over the rails that I can sand with 80grit withought touching the cloth. Sanding also ensure that any amine blush (as a result of low temp and or humidity) is removed. Just my two cents and it works for me. Caution though, you need to get cheater coat timing spot on, too early and it’ll float your laminate, too late and you’ll have the same problem as you are having now!
A little side bar here. Some of us in Hawaii have been using this product with pretty good results: http://tnttinting.com/node/1269. It helps save the rails from paddle nicks.