Hello, I laminated my board using UV polyester resin but did not have a chance to hotcoat it till about a week or so after the lamination. The Lam does not feel very tacky any more. I am worried that when I hotcoat the board that the hotcoat will not adhere to the Lam. Is this possible? I dont understand why the Lam is no longer tacky because the board has been exposed to air the whole time it has sat in my garage so technically it should remain tacky. What do you guys think I should do?
It’s probably covered in dust. Blow it oiff and give it a wipedown with a clean acetone soaked rag and it should be fine.
Thanks insanecutback. I will do that!
Also, you did use laminating resin, not sanding resin, correct?
I know, stupid question but… gotta mention it
Yea i definately used Lam Resin. I was sanding the laps in the nose and the tail where the fiberglass is really thick and my sandpaper isnt getting gummy at all. This just makes me nervouse that maybe my Lamination has lost its tackiness after sitting for a week. But I do have a tendency to worry about things so its probably all good! Any more suggestions or insights would be greatly appreciated
I wish I had the same problem with my last hotcoat when I didnt put enough SA in it, must have cost me 15 dollars in sandpaper! If it ever happens again I’ll remember this thread and leave it a week or so before sanding.
Im not sure about leaving a board for so long before hotcoating, for dirt/dust/grime reasons just as much as adhesion problems, I think most people here must have had experience of touching a lamed board with 'clean hands’only to find fingerprints inside the hotcoat after sanding. Now I always make sure I have a ready supply of sandwich bags for my hands to make sure the boards stay clean whilst flipping them. Its likely that you will just about get away without adhesion problems, wiping down with acetone can help but personally I would stay clear of doing it as I’d be worried about more dirt getting on the lam job. We all do things differently though.
So LiveTheMoment, you think The hotcoat will adhere properly and I should go for it?
As mentioned above you can wipe it down with Acetone and that might work. But— If you are really worried about it; brush on a coat of lam resin, let that set and then hot coat as normal. Yes over a period of time a lam will lose its tackiness, which coild result in adhesion issues with the hotcoat. A coat of lam resin is the cure for the ill. Lowel
Yes, mc ding is spot on- thats a great idea and if you do a nice thin hotcoat it hopefully won’t add too much weight , the chances are that adhesion probably would be fine, although if you want to be 100% sure do what mcding says
I don’t feel tackiness has anything to do with adhesion. The wax in sanding resin is what prevents adhesion in that application, but without wax you should be fine as long as the lamination is clean with no contamination.
Once you sand the wax off a hotcoat, there isn’t problem with the gloss adhering, and there is no tackiness there.
I always thought that the tackiness of the Lam coat helped the hotcoat to bond chemically with the Lam. I was under the impression that gloss coats bonded well with sanded hotcoats because the glosscoat can bond mechanically with the sanded hotcoat even though it is not tacky. The Lamination is not sanded therefore there are not the tiny scratches all over it for the sanding resin to mechanically bond to. I was thinking of maybe light sanding the lam to give the hotcoat a prepared surface to bond to but i dont want to jeopordize the strength of the fiberglass by sanding into it. Mcdings solution sounds great.
Hot Coat as normal.
Some of my “project” boards sit weeks before Hot Coat.
Being that dry gives you the opportunity to sand bumps and lums anywhere inthe board.
Bumps in the lap, tips can be cleaned up and Etc…
Makes for a smooth, easy sand job.
I squeegee a Hot Coat mixture on the flats and brush it on the rails as a cheater coat.
As soon as it kicks, I Hot Coat as normal. (Don’t wait too long!).
A thin Hot Coat usually.
…the tacky thing is due to the evaporation of the monomere so the reaction is done but in reality never fully cure; so yes, you can put the hot coat whenever you want.
Main problem (more if you only did couple of glassing works) is the bubbles regarding a dry lamination + a density that soaks too much resin; so yes, if you let the lamination several days you should do as Barry Snyder is saying about using a squeegee and then the brush.