Well, I haven’t used the RR’s with the Add. F. But, I’ve found:
Lam as dry as possible, but don’t bother with sealing the blank. Use about 2 oz of resin + appropriate hardener, per ft of board, per side, to lam 6+6+6 or 10+10. So for a 1:2 mix, you’ll end up with (mixed) 3 oz x 6’ x 2 = 36 oz to lam a 6’ board. For each side, you’ll pour out about 10 oz on the flat area & work it all over the board with a hard plastic squeegee, moving slowly enough that you don’t get foaming. Then pour 4 oz along a whole rail side & hand-saturate the lap (or fold it up onto the deck to pour that bead and flip it down once its all wet out). Then use your last 4 oz for the other side. Those amounts sound about right to me.
Don’t skimp on the hot/gloss coat. This is the hard part with epoxy because the long open time can be just too long. You can’t just pour it on & do your brush pattern and watch it kick like poly. If you do a dry enough lam, you should see cloth texture everywhere after your lam is dry. You will need almost as much epoxy for a good hotcoat as you did to lam. Maybe instead of mixing a total of 18 oz per side on a 6’ board, you’ll want to mix 12 or even 15 total. When you hotcoat too thin you get way too many zits, bare spots, and drips. But it stays open so long, a thick hotcoat will all run off the sides and leave even more bare spots.
So I’ve done three things & all work.
One, I’ve mixed a batch and literally let it sit in the bucket for 20 minutes before starting to use it. Its 30 minute pot life, so it works out. You will feel it get warm, but if it starts to bubble or gets really hot, you waited too long and if you try to use it it’ll be horrible to work with.
Two, you can also use Cabosil to thicken it up. That actually works great and makes the resin stick together much better. I did a whole deck side hotcoat and had maybe 20 drips off my rail tape. The only problem is it doesn’t set up quite as crystal clear, so I wouldn’t do it over a tinted board or color work. On a deck that’s going to be covered with wax, it doesn’t bother me at all.
Third, you can do the hotcoat as a lam with a layer of 4 oz and thicker resin than you did on your stronger, dry lam. I just did this on a snapped board I was putting back together. After setting the 2 halves and sanding away the old gloss & hotcoats and into the original weave a little, I did a tinted 6+6 lam in bright red to make it look like a competition band, not a repair. Really dry lams. Then a wetter lam of 4 oz with clear resin over each side, lapping over the cut edges of the tint onto the original clear glass. The cloth holds the resin from running off. I still let it sit in the bucket for maybe 15 minutes after mixing, to let it start to kick. But the epoxy is so hard, final sanding with 100, 150, 220, 600, steel wool, comes out great. Then 3 coats of Future & buff it out…beautiful.
Maybe the Add F solves these problems. I think its a liquid too, so I don’t know how it could help you thicken up like Cabosil does. But be prepared & don’t go short on the hotcoat resin…