I use Sun Cure resin on all my boards i glass, for both lam and hot coat. When it comes to hot coat I start with the bottum of the board and I do exactly what I am supposed to do, like let it sit for 3 min then flash it in the sun then back in for a few seconds then back out in the sun for the remaining cure process.
But when it comes to when I put the hot coat on the top of the board, when I am letting it sit the for the 3 min to let the wax rise it starts to like separate from other parts of the resin and makes these weird lines were the resin splits and i can see the laminates were the resin splits perfctly.
Ive tried were I clean the lam first with acytone and sanding it a little.
What else should I do or what could be causing these problems?? Thanks A lot.
Kick your hot coats with catalyst like normal and then just take them outside in like 20 minutes to harden all the way. Sounds like you are using too much resin and they are shelfing.
Immediately after brushing on the hot coat you should walk the board out into the sun and “flash it” for like 10-15 seconds. Basically let the sun kick the UV Initiator off and start the curing process. Bring it back in and leave it on your racks for 2-4 mins until you see the wax sheen come to the surface. Then bring it back out to fully cure in the sun for about 5-7 mins.
What Brad said above is the correct way to flash and harden a UV hotcoat. But; Agua is correct. If you are having issues and nervous about it shoot a little catalyst to be sure it goes off. Doing it the way Brad described; I never had any trouble with a UV hotcoat even on those Central Coast overcast days at the "Chicken Ranch".
And PS; I never used the name brand "Sun Cure". For many years I used "5's" of Silmar 249 with UV premixed and purchased from Fiberglass Hawaii both in Calif and on Maui. No problems. Later I started buying UV powder and normal 249. Uv-ing my own as needed.
combsurf for sure do what all these guys are telling you to do. I was told the same thing about flashing and the times, etc. The problem I had though when I did the 3-4 minute then flash step was that the sun was never consistent enought to get it just right. Sometimes cloudy sometime blazing bright.
So I found that after brushing the deck I’d wait more like 8-10 minutes or longer depending on the size of the board to let the resin level out and the wax to rise on it’s own without the flash. Brush marks level better and it gives time for the wax to fully rise to the surface.
I do my deck before the bottoms and run my finger over the small resin curtain without tape to flatten the resin edge on the bottom. One time around the board then out into the sun.
Flip the board bottom up, quick wipe with acetone on the rail, tape then shoot the bottom, wait for the resin to level in the resin dam at the tail and the rest of the board then out into the sun.
Never had any problems with weird separation or sticky sand coats.
It slabs because its either too thick, or you are moving it..and causing it to slab....or you got way too much air movement in the shop. Just like above. I always put a bit of cat in my suncure because I have to walk my boards outside. The cat will kick it enough so it has tension strength..then the sun kicks it rock hard.
If you put wax paper on the slab lines (take the air way) it will help kick the sticky places where it slabbed, and help the sanding of that mess.
Also dont put the HC on so thick. 1) do a better job prepping the laps for the HC. 2) all you are going is covering the weave and air pins. 2) Hot coat is not a structural part of the build, HC is just a filler, it's meant to be sanded down.
All of the above answers are right. It’s just a choice. Slabbing usually means too thick. Unless you are in a big hurry I see no reason to be running back and forth with flashing etc. Just catylize the resin and let the wax rise.( I actually let it gel), and then take it oustside for flashing. Even with taking my time I can do both sides in an hour or so.
Started using UV cure this year with no problems. I do it the way McDing and Cleanlines do theirs. Add some cat, let the wax rise and bring it out for final cure. No need to flash it, too much of a chance to hit the board on something.
Make sure your SA is good and the wax is dispersed throughout. Pour out your HC, brush nose to tail, then do a 45 degree pass across the whole board and rails. The 45 degree passes gets rid of the excess resin. I do a light final pass nose to tail to smooth it out a bit then WALK AWAY!!