Nemochad,
If you take too long to type in your response, your name is deleted. Don't ask me why.
+1 on no wax paper. I've been posting against it for over 10 years here, but people still want to give it a try.
And good karma for taking in strays.
All,
The best alternative to peel-ply that I've run across is paper towels. I got the idea from a builder who posted here about using toilet paper on his model airplanes. Paper towels were sturdier and more absorbent.
Basically, you wet out the glass as usual, then lay paper towels on it and gently push them in place. Leave them until they've soaked up all the resin that they'll hold (1 minute or less) and gently peel them off. This will leave bubbles and patterns on the glass, so immediately tip it out with a foam brush.
What this accomplishes is blotting any excess resin (like peel-ply) so you don't have to worry about floating the glass or having uneven bumps to sand off. It also increases the glass to resin ratio, making a lighter stronger layup. It does not leave a smooth matte surface like peel ply does. Instead, it leaves a prominent weave that's ready to fill with either fairing compound or more resin. Here's a panel on my schooner that shows the kind of surface that paper towel blotting leaves.
Larger image at http://www.morocz.com/BoatBuilding/images/schooner/10_PuzzleJoint.jpg .
Good luck,
Laszlo
>>>>>In the CLC website instructions on using peel-ply they say that it cannot be used on curved surfaces. I think they are talking about compound curves here. >>>
Just so. Anything that curves a lot in two directions---like the hull of a strip-planked kayak, say, would be impossible with peel ply. It's not stretchy like fiberglass. But if it's a "flat" 2D curve, no problem.
By the way, Chad, that's some beautiful carbon fabrication a few posts up.
Thanks, and, I beg to differ! By cutting slits or gores in the fabric (think mercator projection of the globe, if that helps), or just cutting it into strips beforehand (I'd guess 18"-24" for most strip kayaks, smaller at the ends), the very modestly compound shapes of a kayak will be no problem. Here's a *much* more greatly compounded shape (small sailboat cabin top):
I understand the company policy being reluctant to endorse a complication like this, and I'm just presenting it as an enhancement for folks that really want to save weight and are willing to spend a little time procuring and learning and applying this extra tool in the toolbox.
One other procedural enhancement that I think anybody can apply is to wet out things like tape or other small/local reinforcements on a bench on some plastic, using an auto-body spreader instead of a brush, and somewhat firmly (low angle modest pressure) squeezing out the excess from the cloth. Then, carry the wet tape to the boat and press and work it into the corner (which has already had epoxy freshly brushed on and the fillet still at least green) with your gloved fingers, and maybe some light teasing with a brush. Basically, avoid using a brush to wet out cloth whenever possible --whole-cloth sheathing on vertical surfaces being a notable exception. This will get you to the same place approximately as Laszlo's absorbent dabbing technique. Ah heck, while we're going crazy enhancing... those tapes and reinforcings (probably more applicable to bigger boats with either biax tapes or heftier weaves) can be wet out on pp, then the two carried together to the boat and applied to the seams. Pp or just the plastic on the bench you're wetting-out on also works especially well to carry bias-cut cloth from the bench to the boat, where the cloth would ordinarily turn into an unmanageable stretchy mess.
-Chad
Now you have me concerned that I used wax paper on some surfaces. So I did a test:
Last night I put first coat of epoxy on the daggerboard trunk with a brush and tipped it, (no wax paper) but the surface this morning has no drips but is pretty rough and needs sanding. I just went out there and water does bead up on it a little but not much. I wiped some alcohol on it and basically no change in the slight beading of water.
Last night I also put the last coat of epoxy on the mast step brushing it on and putting wax paper on the top and sides and smoothing it out. (no wax paper on the inside). Just went out and no matter how much I rub the top of the mast step with alcohol, water still beads up a lot on the mast step where I used wax paper and not as much where I didnt use wax paper.
So, I'm convinced, I wont use wax paper on epoxy but what do I do with the surfaces I epoxied where I did use wax paper? Go ahead and sand after rubbing with alcohol?
Thanks
Curt
For a known wax problem, I use acetone first, using paper, disposable rags. This used to be all you needed, but with the solvent companies using reclaimed sources more and more, today's acetone isn't always as clean as it used to be. So I wipe with alcohol next, then scrub with water and a scotch-brite pad. (Note, for the wax-like amine blush that occurs with some epoxies, use just the water and scotch-brite.) If recoating with epoxy, sand to 80 grit for structural stuff, maybe just 120 for a plain coating.
You can skip all this solvent stuff by coating/bonding wet-on-green epoxy. Blush, if it occurs, seems to happen in the final green-to-hard curing stage. And, while it is still green the epoxy has free molecules to bond to those in your new coat. (Don't let this be a big deal for your work flow, though- an 80 grit sanded surface provides a really good mechanical bond.)
Just before adding a paint finish, I use one of the paint companies' really gnarly solvent wash products to be extra sure any wax is gone.
>>>>
1) The mast step that water beads up on is going to be varnished and I had planned on sanding with 80, 120, 220 and setting it aside in the to-be-varnished pile. Is that OK?
2) The thwarts will be varnished where I did wet on green and used wax paper have already been rough sanded. OK to go ahead and do 120, 220?
3) On the boat floor, which will be painted, where wet on green and used wax paper, almost all of it came out great but I have a few of these:
<<<<
1- Wash it first: acetone, alcohol, abrasive pad and water; then sand.
2- Same again, and I'd repeat the washing steps after sanding. (can you tell I place a high value on washing, and realllly dislike wax anywhere near my projects???)
3- If they are trapped under glass (that's what the pic looks like) they *probably* won't be a problem. If you can press them with your finger tip and make them move, I'd dremel (or abrasive stone in a drill) them to open them up a little and dab some epoxy in/over them. Doing nothing, worst case would be slight pimples that show when the paint is on, after the first hot day in the sun.
Chad,
Thanks for answering my questions, as well as the others.
Lot of good info here.
Might be a bit of a learning curve, but I can always use the mold for a second try!
That 24 hours is a serving suggestion. Check the data from the epoxy manufacturer. System 3 SilverTip, for example, can go 3 days between coats without sanding.
Laszlo