Epoxy over PU (Epoly, Etech, etc)

LifeOnMars

Michael Peterson status
Jan 14, 2020
3,164
2,106
113
In terms of quick UV fixes it seems too tempermental. I don't know if it's the quality of the product or epoxy itself.
Seems to need blazing hot sun to cure. had a tube of epoxy solarez that I thought was done, used it in Indo this past season and it worked just fine
 
Last edited:
  • Like
Reactions: MathDebater

JBerry

Billy Hamilton status
Dec 8, 2017
1,602
872
113
I appreciate everyone's input here, thanks.

Perhaps to keep this from turning into a thread specifically about R. quality, I'll ask another question.

If epoxy/PU doesn't come with any significant disadvantages, why have shapers tended to put epoxy over EPS blanks? Why use EPS at all?
The biggest disadvantage is cost. Epoxy resin over PU is about 50-100$ more than a standard pupe board. Surfers are notoriously cheap. 2nd biggest disadvantage is time. It takes a lot more labor to glass with epoxy resin. IMO it doesn't really give you too many extra strength advantages over pupe. It may be stronger, but it dents the same, and is unnoticeable. It also will yellow a lot faster than a standard poly resin.
Why use EPS? good question.......
 
  • Like
Reactions: Havoc and JDJ

GromsDad

Duke status
Jan 21, 2014
54,141
16,164
113
West of the Atlantic. East of the ICW.
No it’s not.
NO? News to me.
Seems to need blazing hot sun to cure. had a tube of epoxy solarez that I thought was done, used it in Indo this past season and it worked just fine
My comment about ding repairs is not about the ability to do a small instant repair with solar rez. I'm talking about doing a quality professional repair job. I can bang out repairs on PU/PE very quickly. Throw epoxy in the mix and everything takes longer and there are more hassles to get the same quality in a repair.
 
  • Haha
Reactions: LifeOnMars

Waterlogged05

Michael Peterson status
May 14, 2005
1,923
1,822
113
NO? News to me.

My comment about ding repairs is not about the ability to do a small instant repair with solar rez. I'm talking about doing a quality professional repair job. I can bang out repairs on PU/PE very quickly. Throw epoxy in the mix and everything takes longer and there are more hassles to get the same quality in a repair.
Yea, little stuff with epoxy is easy, big jobs, eesh
 

doc_flavonoid

Billy Hamilton status
Dec 27, 2019
1,740
3,198
113
NO? News to me.

My comment about ding repairs is not about the ability to do a small instant repair with solar rez. I'm talking about doing a quality professional repair job. I can bang out repairs on PU/PE very quickly. Throw epoxy in the mix and everything takes longer and there are more hassles to get the same quality in a repair.
easy to bang poly repairs because it doesnt require any real cat to resin accuracy and is not all that temp/humidity sensitive?

whereas with epoxy mix accuracy is critical. if weighing ingredients and proper mixing is too much of a hassle for you then yea stick with poly.
 

GromsDad

Duke status
Jan 21, 2014
54,141
16,164
113
West of the Atlantic. East of the ICW.
easy to bang poly repairs because it doesnt require any real cat to resin accuracy and is not all that temp/humidity sensitive?

whereas with epoxy mix accuracy is critical. if weighing ingredients and proper mixing is too much of a hassle for you then yea stick with poly.
Small batches of epoxy I do using syringes......one for resin and one for hardener and they are marked so they don't get mixed up. Like you said, still a hassle. Then you have the long cure time at every step. Its very temperature sensitive. Then you have the heat epoxy generates on fills. Then it doesn't sand so good. Blending new into old is a pain. You have to prep the hell out of the area of the board you're working on otherwise you'll get fish eyes. When people ask me to fix their boards most of the time I direct them to a local surf shop if its epoxy. I'm anal about board repairs and its just too much of a pain to deal with epoxy to get the results I want.
 
  • Like
Reactions: daave

rowjimmytour

Tom Curren status
Feb 7, 2009
11,534
5,832
113
54
Small batches of epoxy I do using syringes......one for resin and one for hardener and they are marked so they don't get mixed up. Like you said, still a hassle. Then you have the long cure time at every step. Its very temperature sensitive. Then you have the heat epoxy generates on fills. Then it doesn't sand so good. Blending new into old is a pain. You have to prep the hell out of the area of the board you're working on otherwise you'll get fish eyes. When people ask me to fix their boards most of the time I direct them to a local surf shop if its epoxy. I'm anal about board repairs and its just too much of a pain to deal with epoxy to get the results I want.
Easy cure to all......
70 degrees is perfect temp
Weight by volume in grams digital scale 2:1 (epoxy:hardner)
Mix in plastic cup stir slowly scrape bottom and sides with popscycle stick 3 minutes
Let epoxy sit 5 minutes after mix in cup before using.
 

doc_flavonoid

Billy Hamilton status
Dec 27, 2019
1,740
3,198
113
Small batches of epoxy I do using syringes......one for resin and one for hardener and they are marked so they don't get mixed up. Like you said, still a hassle. Then you have the long cure time at every step. Its very temperature sensitive. Then you have the heat epoxy generates on fills. Then it doesn't sand so good. Blending new into old is a pain. You have to prep the hell out of the area of the board you're working on otherwise you'll get fish eyes. When people ask me to fix their boards most of the time I direct them to a local surf shop if its epoxy. I'm anal about board repairs and its just too much of a pain to deal with epoxy to get the results I want.
im super ocd when it comes to results.

gotta use a digital scale to accurately weigh the ingredients. other than that i find the epoxy application and finish process superior to poly. obviously ymv
 

rowjimmytour

Tom Curren status
Feb 7, 2009
11,534
5,832
113
54
just had this nightmare. ironically.....the suncure i sued didnt kick...the the stuff i used with catalyst worked great. i can't measure catalyst to save my life.
Never understood why people waste time with suncure unless your on vacation better just to stick duct tape over it or even better use epoxy putty no sanding.
 
  • Haha
Reactions: LifeOnMars

Senor Sopa

Billy Hamilton status
Mar 11, 2015
1,366
2,176
113
Ponto
If epoxy/PU doesn't come with any significant disadvantages, why have shapers tended to put epoxy over EPS blanks? Why use EPS at all?
Because polyurethane resin melts EPS foam. Good way to make napalm knockoffs.

easy to bang poly repairs because it doesnt require any real cat to resin accuracy and is not all that temp/humidity sensitive?

whereas with epoxy mix accuracy is critical. if weighing ingredients and proper mixing is too much of a hassle for you then yea stick with poly.
I have an old skool triple beam. Small batches suck, you need to be precise. 1 gram out of 10 is fubar. Big batches are much harder to mess up the ratio.

Easy cure to all......
70 degrees is perfect temp
Weight by volume in grams digital scale 2:1 (epoxy:hardner)
Mix in plastic cup stir slowly scrape bottom and sides with popscycle stick 3 minutes
Let epoxy sit 5 minutes after mix in cup before using.
The two resins I've used, RR and Apex have a 100:44 ratio.
Be careful on the 5 minutes if your running 100 g batches. Don't want to melt your red cup.
Vinegar and paper towels to clean up. Fook acetone!!!
 
Last edited:

shaheeb

OTF status
Feb 24, 2013
255
69
28
had negative experience with two epoly boars. after sum time the boaar started to shrinkage, stringers start raising, etc. weird dents on bottom. the shapers said they had seen a few. blame it on the heat n sun

tiduk bagus
i'm sticking w pu/pe