Thanks for all the content on here, it’s absolutely incredible. I just finished my first board and had a blast. Wanted to ask a few questions to hopefully hone my skills
Futures boxes was tricky on a board with moderate double concaves (modeled after Machado Seaside). Lining up and leveling the template was fine, but getting the depth right was a little tricky. Any tips on this?
Sanding the double concave with the rotary sander was rough, I never did get it right. Any tips for tight concave spaces like that?
Sanding the fin boxes down was also a bit of a nightmare with the concaves, was hard to get the fin boxes level without digging into the glass elsewhere.
My laps were too big and probably contributed to the deck and bottom not being perfectly smooth. Should I just sand the heck out of the laps so they don't cause ridges?
Carbon fiber tape was tough to get straight, especially at the ends where it came unraveled, almost seems not worth it. Any tips?
What's the best way to deal with rail ridges on the final coats? It almost seems better to not mask them or mask at the very bottom of the rails and then sand flat? I kept burning through to the glass trying to basically reshape the rails to knock down the ridges.
My final coat had a bunch of little "gloss" marks that were lower and didn't sand, almost looked like rain drops fell all over the board in certain light (photo below). Do I just need to sand deeper or is this contamination or bubbles?
I have a couple spots that look like minor burn through. It sounds like I at least need to spot seal them? (photo below)
Can’t address “cosmetic” issues at the moment. But you should be happy with a difficult shape for a first board that turned out so well. Next time; power sand the flats and hand sand the rails and concaves. And do a “cheater coat” when you laminate. Don’t ask, just look it up. Get out and ride it. See if you like it.
Thanks for the reply. Since this was my second resin coat I decided to just sand the crap out of the whole board and do another resin coat. It also allowed me to sand down any remaining high/low spots. Final sanding today so will follow your advice. Hopefully surf it tomorrow!
Board looks great. You chose to build a difficult shape along with concaves, fin boxes and such. Learn from this one and on the next one figure out procedures that will make the process easier. Ride it figure out what you like and dislike about the board and incorporate the changes on the next one.
Regarding cutting your carbon fiber tape, try this. Take a piece of copy paper or a little thicker if you have it and fold it in half. Now take your carbon fiber tape and place it in the folder you’ve created so that its up against the fold to keep it aligned. Now with a good sharp pair of scissors cut it paper and all cutting from the fold.
Regarding your sanding issue. Open up the box with a hard pad. Given your concave you should use a softer pad and be mindful of where you are applying pressure to the sander. Apply more pressure to the side of the pad where the sandpaper is exiting the rail. I have a feeling your sandpaper was cutting entering the rail. Don’t know if that makes sense the way I explained it. Might be something best demonstrated.
Many thanks for the thoughts. I’ll try the carbon fiber cutting trick on my next go. I think I get what you are saying about sanding, I want to angle the wheel so that it’s spitting the dust out over the rail, rather than toward the stringer? I imagine I also want to be dragging the disc down the board (moving the sander in the direction of the high side of the disc) rather than pushing it up the board?
Avoid tipping the sander, or pressuring the edge, that will make swirl marks. Also, tipping the sander puts more pressure on that side, and pressure leads to heat. Not a good thing. Listen to McDing on this one, he’s built a lit of boards. Keep the sander flat, hand sand the hardest curves, use your trigger to control the speed. You will have less burn throughs at low speed. Then to get the totally even finish after the orbital sander, see if you can get a 1/2 sheet vibrating sander, not the cheap 1/4 sheet Jitterbug. A porter cable 505 is the best if you can fi nd one used.
Thanks for all the replies guys, much appreciated.
I’ve got the soft pad on the sander (only use the hard one for fin boxes and leash plug), but it’s an 8" pad and just doesn’t fit inside my concaves. Maybe that’s my problem? Would a 4" or 6" pad help? However, if I do angle it, it seems to conform to the concave pretty well, just have to keep the pressure light. I’ve got the cheap harbor freight digital sander so no trigger, but I’ve been doing 1500 rpm for the rougher grits (120/150) and 1000 for the 220/320/400 and it seems to be working ok. Cleaning the dust off the paper often seems to help too.
After heavy sanding and re-coating the board it turned out much better. I’m realizing the importance of a cheater coat and getting everything perfectly flat before the final coat. So much easier. I was able to be more aggressive with the flat areas knowing they were perfectly flat which made for a really nice matte finish after wet 320/400. I’m also realizing that maroon scotch-brite is one of my best friends–with pressure it smooths out swirls and rails and with a light touch and cross hatch pattern it’s almost as good as 400 for a finishing touch.
I think I still need practice with the sander though. I just can’t keep it flat. I feel like I’m there and then it starts grabbing on one side or the other so I purposely give it just a little tilt so it’s more predictable. Also, do you cut your paper to the size of the pad or leave a 1/2" extra on the outsides? I tried both and I think I like it cut close, maybe just a hair wider than the pad.
Still one problem I haven’t solved. With the concaves the resin tends to pool in the concave, especially at the tail where the tape is damming up the tail. My thought was for next time to NOT let the tail be level, and either raise the tail so the resin all runs off the nose, or drop it and keep the tail dam as low as possible so it overflows the tail dam easily and I could just sand down the dammed part. Thoughts?
So, summary of questions:
Would a smaller diameter pad help me stay flat in the concaves?
When cutting paper how much do you leave outside the pad?
Any help on managing resin pooling in the concaves at the tail?
Surfed the board yesterday and had a great session. Really happy with how it turned out.
