So I have a few issues with my sanding. I am not getting rid of small dips in the hotcoat. I am using a hard disc for my initial sanding with 80, 150, 240 grit; and then touching it up with a soft pad with 240 grit and then going to 300, 400, and then 600. My issue is that I am not getting rid of the little dimples, they can still be felt when touching the board.
Also, if you only had a limited amount of money, what two pads would you get for all your jobs? I am thinking of getting new stuff and was going to go with a 6" softie and medium pads.
My .02 - If you still have dimples after 80 grit and a hard pad, I think you need to address your hot coat technique and maybe even your lamination, not so much your pads. Your hotcoat is only as smooth as the lowest spot
Glassing is like painting its only as good as your primer like your lam and may be your hotcoat isnt geling fast enough hotcoat need to gel fast so they dont sag or run and you dont need to use alot its only a filler its not your pads Good Luck
I always think of glassing a surfboard the way my father taught me to tape and spackle sheetrock. Its a lot easier and you will get better results if you work neatly rather than sanding it down after globbing it on. If you use a lot of care in the laminating and hotcoat process you won't have to do near as much sanding. I'm using a soft pad with 80grit for most of my work now and then working up to 400.
PS: One of the things I absolutely love about UV cure is the extra time I have to make absolutely sure everything is perfect before firing it off. It makes such a difference to have your laps perfect. Just flip and go for the second side with very little extra effort.
To clarify the dips I am talking about are tiny but can still be felt. My lam job was good, no air bubbles and I got the cloth down tight. The only thing I can think is that my hot coat is too thick and is kicking too fast while I am spreading it.
Simple fix… don’t consider that first hot coat the last. Sand that first one down (especially the rails, tail area) don’t worry about sand throughs or cloth showing just get it as smooth as possible. Then do a SECOND hot coat to fill those little holes etc. Then since it was already close to perfect before the second coat it will be way easier to finish sand the second. You can start sanding with 200 then work up to 600. Boom.
After your hot-coat has kicked and before you sand, thicken your resin a bit, then squegee it smooth over the little pinholes. It's thick enough to stay in place, then sand. But a second hotcoat might be inevitable if that doesn't cut it? Also I've been using a 45$ Black and Decker random orbital sander and getting great results. It doesn't heat up the board's surface the way an orbital does and the sander cost about as much as a pad for the other. It makes it really easy to blend those spots you might have to touch up, but can tackle a whole board in no time.
wait as minute here. Before you hotcoat you lam should look like a hot coat. Or i should say it should be perfectly flat and flush. All seams should be flat and flush. Then when you put the hotcoat on the board should look pretty close to a gloss coat. The only bumps should be from the tape line, and or maybe around the corners.
if you are not acheiving this yet, then your glassing has to become a bit better. Using a hot coat to fill woop's and wobbles is not the proper technique. The hotcoat is only there to fill the weave and pins in that lamination. Remember resin is only the glue that holds the cloth in place, and makes the cloth water tight. resin is not structural, and should not be used as a leveling agent to fix problems.
I know what you are talking about, those little wobbles you get (usually in the bottom rail line of the board, usually around the nose, about where the rocker starts to kick).
The fix is solid glassing skills, and a better prep job before you hotcoat. I mean, your foam blank didn't start with wobbles..err..right? So there's no reason the glass job should have wobbles.
So if it's the sanding technique..go back to a sanding block on the rails. A sanding block will not lie. If it's the sanding pad with grinder, then check your skills..dont press too hard, and keep the pad flat and moving all the time.
Lot's of advice above, some good . It sounds as though you are getting a tight lam. After the lam You may want to consider a "cheater coat".. Which is nothing more than a second lam coat of lam resin after the initial lam has jelled. Most guys put it on with a squeege, some use a brush. This will insure that you didn't pull too much resin off during the lamination. It also sounds as though your brushing technique may need improvement and you may not be pulling enough resin off when laying off the hotcoat. If they are pinholes; it is most likly that air is trapped beneath the resin as it sets. Which means you need to work faster at laying off the hotcoat and improve your technique.
So I wanted to thank you all for your advice and after putting in a few hours of work today I think I know what my problem is. After looking at the dips I think, as other said, I was working the hotcoat after it had already kicked and gelled. Some of the dips clearly looked like I had pulled the gelled resin off the deck and left brush strokes. I sanded the sh!t out of the thing today and worked out alot of trouble spots, so hopefully it will just be another hotcoat and some light sanding and that is it. I will post some pics when I get done.