Can you cover over improperly mixed epoxy resin with properly mixed resin?

Question

I used the wrong amount of hardener in the epoxy that I used on the hull of a plywood boat. It has been two weeks and the resin still isn't dry on the fiberglass tape. can I just mix some more epoxy ( this time with the right amount of hardener ) and cover over the the entire hull?

Answer 1

as ( amongst other things) I am a builder of sailboats, and have mixed and spread  A LOT of epoxy in my life

No.

All you will do is have a mix of epoxy that is still under catalyzed;

( 4+1 + 4 + .5 doesn't equal 8+2. as an example;)

after two weeks you have a chemical reaction that has produced SOMETHING, but not epoxy; scrape it off and then rub  off the remainder with acetone, denatured alcohol or toluene, WEARING GLOVES AND BEING PARANOID ABOUT FIRE; then wash the alcohol residue off with soap and water,  rinse and then try again.

We've all done this 'just how much catalyst DID I put in there?" space out at least once in our lives

Answer 2

No.

Sorry, but you are asking for big problems if you do that.

Remove as much of the failed application as you can before you proceed.

Again, sorry, but that's the facts.

Answer 3

yes, if you put the next layer on while the previous layer is still tacky, you'll get good adhesion.  Once you cover over that uncured resin, it'll cure.

no air pockets, yada yada yada.

Answer 4

It's very iffy, I've tried it a few times, but I'd not recommend it, unless there's just no other way.  Sorry Tex I've got to go with Jim on this one.      P.S. In my other life, I'm an expert in Plural

Component Materials, like urethane's and epoxies.

Answer 5

Hate to disagree with jtexas, we usually are in sync, but in my experience, if you go over uncured resin, you may not get a good bond to the original surface.  I'd scrape and clean off the old with acetone, reprep the surface, and start again.