Epoxy and tint question

General Discussion
1

Am going to be starting a fish for a friend of mine in a couple of days. He wants a green tint done on it and I have been thinking about how to accomplish this with a 6 x 6-6 lam schedule.

I am thinking that it will have to go like this: Work out color mix… lam the bottom of board in green. When it has set, but tacky, do the cutlap and then do the butterfly tail patch in clear. When that has set, lam the top with one layer of 6oz with green tint(same mix as bottom). After that has set, cut the bottom laps and then lam the second layer of 6oz on the top in clear. (with the logo lam under it) Then proceed to hotcoating…

Does this sound like the right proceedure to everyone?

I am also wondering about the timing with the epoxy. You’re supposed to hotcoat inside of 24 hrs to get decent bond, otherwise you have to scuff the board. I am assuming that the same timing applies to lamming other layers on? What is the time limit for lamming another layer onto a cured one?

I also think that scuffing/sanding a tinted lam is not something that you want to do. Does this mean a long day of lamming in store for me? :slight_smile:

Or can I carefully scuff up a tinted lam to get a good bond? Is it necessary?

2

Johan,

I’d suggest a slightly different schedule, for ease of production as well as aethetics.

Do your bottom lam as described. Assuming you’re using RR and are at decent temperatures, come back 1-1.5h after layup when the lam is tsill tacky, but fairly set up and apply a clear, untinted sweetcoat; about 1/2 the amount of resin required to get the lam done. Apply uniformly with a roller. Wait for this to go off good and proper; full cure so that it’s sandable. Do your cut-lap. If you’ve done a good tape job, peel-up won’t be a big issue. Sand the rails back to where you want the bottom cutlap to be. This will sand pretty smooth; almost hotcoat like because of the sweetcoat.

Then, for your deck, assuming you want double tinted rails, do your 1 layer of 6oz with laps on a good tape-off. As soon as you have enough consistency to trim, do so. Lam your clear 6oz on top of this, with particular attention to the laps on the bottom of the board; once this clear layer has gone for 1-1.5h, apply untinted sweetcoat.

Sand whole board, taking sweetcoat more or less down to the weave, but careful for no sandthroughs; any time you get in to the weave, you’ll be making uneven colour patches. Then hotcoat whole board as normal. Let it go off good and hard. Sand right through to polish.

It’s a lighter than a true glosscoat, a little easier, definitely more structurally robust, but will still give you comparable optics. AND, it allows you to get everything done on a timeline that works; first lam on a given evening; sweetcoat just before bed; wake up, sand rails a bit, top tinted lam, check in a couple of hours later and clear lam, couple hours later sweetcoat; baboom, you’re done in 1.5 days, ready to sand before next coat the day after you finish the sweetcoat.

hth

g

btw; the boards in the other thread look great! Trips to NS in order I guess hey?

3

Thanks for the tips G.

That sounds like a much more… practical process.

What kind of roller are you using? A little foam one, or a short nap one?

And yes, there will be surf trips starting very soon (NS, Maine, New Hampshire). Trying to get a hook up for an xcel 4 mil suit. Probably be heading down to the river soon too, but do prefer the ocean.

thanks again, for the tips, and the kind comments.

4

little foam ones ('bout 4" long) that you can buy in a four-pack at Home Depot. They run about a bunck a piece and are destined for the garbage as soon as you use them, so not great from a consumables perspective :(. That said, I generally use the same roller for all my sweetcoats; I just toss it (along with the mixing cup) in the deep freezer as this more or less halts the cure. Then, next sweetcoat, bring it out; warm it up in front of the space heater and apply next sweet.

should add too; if you want to make your life easier when sanding; apply the sweet coat a little heavier right along your cutlaps; it’ll mellow out the little ridge there and sand much smoother. Everywhere else, just make sure it’s thick enough to hide the weave and not much thicker than that. They lay down much nicer if you warm them up before you go to apply them (kinda like the ladies…). Don’t forget your additive F in the sweetcoats. I’ve been skipping it in the lams, but pretty essential in the sweets.

Also; if you want your lam uniform in colour; a recommendation…calculate out approximately how much resin you’re going to use to lam your tinted layers; you know…1:1 total resin weight to glass weight; from there, calculate out how much of that resin mix weight is actually resin (not hardener), so about 2/3 or total glass weight is resin; pour that out in to a mixing cup and apply your tint BEFORE you ever mix a batch. That way you’ve got pre-tinted resin that just requires a swirl, a pour, some hardener and some mixing and you’re off to the races; no counting drops then when it comes to doing your deck lam. WAY better results when I figured this trick out.

my buddy dave sent me pics and vid of him surfing the river when he was at school at McGill last year…tell me you don’t use the rope; he said it was for people that walked with crutches and rode bikes with training wheels ;).

5

Hahahaha

No, I have never used the rope. It would just seem… strange I think. I wonder if I ever met your buddy down at the wave.

I was talking to a friend who was a rafting guide on a river up north of the city, and he is seeing more people trying surfboards on some of the standing waves on the river. It is a river with some class 4 and 5 rapids on it, so he mentioned that there are a little more hazards than the wave here in town. :expressionless:

Thanks for the help. Should make things go smoother.

6

GWN, I’ve been doing epoxy and color and when I accidently sand into the weave, the grain of the weave shows in contrast to the color. And its hard to get rid of. I’ve been coming back with another step and wiping a thinned coat of epoxy on it to saturate the weave and make it disappear. Otherwise it shows through in the final product since the hotcoat won’t saturate it.

How do you handle this? Do you even see this problem? I know the green tint, when sanded (before flipping for the top lam) will show the weave. thx

7 
Hmm..is a "Sweetcoat" the same as a "Hotcoat"?  I assume it is.  What a neat idea to use a small roller to apply the hotcoat.  How well does it work compared to a brush?  I've never heard of doing that.  I gotta try it.  And saving the roller in the freezer is a neat idea also.  I gotta try that too!  Where did you come up with that method?
8

Read through this post. I do mine in the gloss coat.

http://www.swaylocks.com/forum/gforum.cgi?post=297575;#297575

9

Don’t let Leslie fool ya… if anybody knows epoxy, she does.

I have incorporated her recommendation in my epoxy glassing process and it paid off in spades.

I.E. lam, then fillcoat. No flip.

Like Benny1 does on his conventional lay ups.

After a disasterous experience with epoxy in cold temperatures, I think I know how to do it now thanks to Leslie and Benny1.

http://www.swaylocks.com/forum/gforum.cgi?post=241837;search_string=lam%20no%20flip;#241837

10

I did the bottom lam this afternoon. Your steps worked very well GWN. It came out looking allright. I have lots of respect for the guys who can do tints very well. Tricky!

THere is something that I jadn’t even thought of while preparing for this board. At the nose and tail, and in the buttcrack, where you have glass that folds over the otherside, you end up with a darker uneven patch. Is there a way to avoid this from the beginning? A different way to cut or layup the cloth?

Could I just sand those spots down, so that the thickness will be taken back down to close to the thickness of the one layer of 6oz. cloth? Or might that just cause problems?

thanks for any help.