If you get white and shiny spots, that’s a sure sign of unwetted (enough) spots. Maybe you drew the squeegee too hard, maybe the blank sucked resin, maybe both. Also, glass cloth may have irregular “sizing” (“sizing” being the treatment given to the cloth so that it absorbs resin) but usually one or both of the above are the culprits… I suggest you inspect your glassed blank very closely (with varying lights) just after lamination. If you detect unwetted spots, don’t wait, pour immediately a “filler coat” (you may make it thinner with some styrene so it penetrates easier.)
You should do all layers at the same time. More difficult but less weight.
Grant… when you are done laminating you should just be able to see/feel the weave. You should not be seeing a “pit” between the strands of glass, this is a sure sign you’ve pulled too much resin off the board, or didn’t have enough in the first place.
I hope you’r using UV cure resin, it makes for a lot less drama with timing of the resin. More time means you can do a better job, too.
In my experience, blanks don’t really suck resin out of the glass. Remember, if it’s polyurethane foam, it’s a closed cell foam. EPS is not closed cell, and when using that material we spackle before laminating. Lately since I’ve been using sun cured resin, as soon as the lam is even, I drag the rack and board out into the sun and - wham - it cures. No time for draining or sucking it in. I suspect guys who claim the blank sucked resin in, are really just not putting enough on, or squeegeeing too much off. Anyway, never a problem for me.
I’ll also note that some penetration of the blank by the resin is a good thing because it distributes the shear load when the board is flexed, and may make it slightly less likely to buckle and snap.
Yeah there are not really any “pits” its more like the texture of the weave. Some of it pools a bit more and totally covers the weave, it is very smooth to the touch. Is it better to have the weave texture showing or to be totally covered and smooth?
I am not using UV resin, although I wish I was. Once this bottle is finished I will get UV. How long does it take to set once in the sun?
When laminating you don’t want pooled resin. Your glass job will not be as strong. Wet out all the cloth and then pull the excess resin out. Your hotcoat is for covering the weave and giving a smooth surface. Not the lamination.
Grant-----------------As mentioned by Balsa; You can apply a “filler coat” or what alot of glassers call a “cheater coat”. In my opinion if you have wet out properly, have no dry spots or unessesary pools of resin and have pulled any excess resin off the blank; You are good to go. The purpose of the cheater coat(although it adds some weight) is to fill and make sure everything got resin. Some guys think it makes the board stronger, but I doubt it. When I used to glass my own I used UV and never used a cheater coat. Guys over here in Hawaii favor a cheater coat. Guys on the Mainland don’t. That’s just my observation. I have to agree with my very experienced and high quality glasser in Westminister Calif. ; ‘No need’. There certainly is a technique to using your squeege and the pouring and spreading of the resin. Just the right touch, not too much pressure. More pressure less resin on the cloth and more dry areas. You can tell by the sound of your squeege across the the cloth if you are pulling too hard and taking too much resin off the board. You really shouldn’t be able to hear the squeege drag accross the cloth. Too much noise; You are going to need a cheater coat. Hope this helps. Using UV for your first few boards will allow you the time you need to develop technique. Lowel
Thanks Guys, huge help! I think I was leaving too much resin on.
Do you guys sand the board before you do a hot coat, or do you just leave it as is after the lam.
Now time to put all this info to use, time to glass board number 2. I will post some pics once its done.
Thanks again,
Grant
Grant --------Never sand a lam. Other than grinding your laps: never take a sander to a lam. Hotcoat it, sand it and THEN fix your mistakes.
Useful stuff for me, a pretty crap laminator.
Do you ever weight the cloth and resin to try to get resin loading right (10-20% more resin than cloth)? Or do you just work from experience?
Red---**Experience. And not always the most pleasant of experiences my first few times either. But experience good or bad is a good teacher.**