Epoxy 2nd hotcoat... avoiding fisheyes??????????????

[jimdunlop]

I used RR from '06-08, greenroom '08-'12…switched to fiberglass hawaii aluzine in '13 and all the "operator errors "  disappeared… They came out last year with a new hardener specifically for hotcoats and addressing the fisheye problem. It’s called "thick/fast hardener and I’ve had zero fisheye problems in the last year.

[Swied]

@$1

I use Resin Research and pretty much haven’t seen a fish eye in years.   But there are other good products as BB30 says.   Here is a little snip I’ve saved and pasted here many times:

Epoxy Hot Coat Gloss

Per G Loehr: You’re working too hard to try to make everything perfect and in the mean time you’re adding a bunch of potential problems. After the laminate you sand lightly mostly getting the laps flat and all the high spots down. Wipe the excess sanding dust off with a white Tshirt or a paper towel. Tape off around the perimeter and sqeegee your cheater on if needed. Let that tack up and then brush on your hot coat. I only use 1 cc Add F per ounce of hardener. That’s adequate and using more may give you problems. I only use more if it’s extremely hot (which it never is in SD) or on a gloss. Rolling on the hot coat may have made it too thin which could have made it bead. Use a brush, a new one, a 3" chip brush. If you push the bristles into the sticky side of a piece of tape before you hot coat you can remove loose hairs. If you don’t the brush may shed a bit but unless the board is colored you probably wouldn’t see them anyway. Brush on a normal hot coat.  It should flow perfectly. This is the way I do it … simple. I never get fish eyes.

+1 to this technique of doing a cheater coat with a sqeegee.

I just tried doing it this way last night and got the best results I have ever achieved.  All of my attempts at hot/fill coating with epoxy in the past were plagued by fish eyes, dimples, and tiny bubbles.  I wasn’t even being that careful with cleanlness last night.  My shop floor was covered with sanding dust and I didn’t do much beforehand to clean off the board before applying the epoxy.  

Note that I was using KK epoxy.  The cheater coat had no additive-f, but the fill coat did have a small amount.

[melikefish]

Ditto on the fast. 

BB30 recommended me to start using fast and it has helped a bit. For doing a fill/final coat, I mix it for about two minutes or until it goes from a little cloudy to clear, and then dump it all on the board. I try to brush it out in around a total of 8 minutes since pouring the harder into the resin, and I am still probably way slower then a pro. I found the quicker I get it on the board, and brushed out, the nicer it looks. I also think since I am done with it quicker, I get less bristles in the coat. 

Using the fast has helped since it seems to get a little hotter right before it kicks and kind of smooths out. It also cures quicker so less chance for stuff falling in or drops. 

After flicking bristles off the brush, I wrap some tape around the base of the bristles to help hold any additional stragglers in there. 

Found a lot of good tips by going on boating websites. Those guys have been using epoxy and getting some really nice results for a while. One tip I found on there ,as was mentioned before, depending on how your epoxy has been mixed/cured, you might need to wipe it down with soap and water and scrub it to get rid of amine blush. 

 

[bb30]

so laminate, let cure, sand, tape off, cheater coat to past tacky then hot coat? After that you sand again and then do your gloss coat? Never seen such confusion. Why with epoxy would you not second coat to fill the the weave just past tacky on the lamination. Also where exactly are high spots on a lamination??? If you mean overlaps at the the nose and tail on the opposite side of the board, how does this method help if you tape the perimeter? What does perimeter mean in GL’s post???  My mind is now more clouded than the laps of an alleged over worked RR epoxy cut lap.  

Are you now finished with your board except for sanding and polish or do you still need to gloss coat your board???

Also with an epoxy filler coat why would fisheyes be a concern if your next step is to sand it back to shape then final coat or gloss coat it? Are the fisheyes everyone is refering to from really big fish or minnows? The final coat or gloss would be the part I would want as perfect as possible.