problems with epoxy

General Discussion
1

i shaped my first board last summer, and used poly. seemed okay for a first try, definetly nothing worth any money but she’s water tight and floats. this summer i shaped an XPS (pink HD sheets glued) 7’0 and used R.R. epoxy. i had a few problems with it:

  1. it seemed fairly thick compared to poly, which was expected…but almost too thick. i did this in 60-70 degree nonhumid weather in a garage with the door up so conditions seemed fine. i mixed a little by buckets with measurement lines and some with my digi scale. mixed it up for about 1 1/2 minutes each time. did i do anything wrong? it just seemed way too thick when poured out over the board

  2. because of it’s viscosity, it didn’t seem to spread out over the board easy at all. in fact i found myself mixing up a little extra while to hit the dry spots towards the rails. i went through a little under a gallon set of R.R. on this 7 footer…this doesn’t seem right. i didn’t push into the cloth like i had read…i duno

  3. it seemed to fog/cloud up an awful lot if i touched it and tried to spread it a little too much…like more than two times. making it awfully difficult.

these all resulted in a VERY poor glass job. 3 days after it sitting and curing, i brought it out and it bubbled/delam’d quickly. somewhat expected because of XPS, but not as quickly…especially since i live in maine. it seems to me that the glass didn’t really bond to the foam. my other suspicion is that i used krylon h2o paint which has been okay’d on the forum before…but i am afraid it might have ruined the bond somehow? i’m sure this isn’t the R.R.'s fault at all as it seems like a very sucessful product so could someone please point out any mistakes i might have made so i won’t make them next time.

i’ve also been hunting for ANY videos online of wetting out with epoxy but i can’t seem to find any??

thanks guys! :slight_smile:

2

Sounds like your epoxy was to cold. I would heat the part a and b in separate containers in warm water or the microwave till it was at least 80 degrees. Your mix may have been off as well.

The stuff I have used twice now seems to work really well but I have never tried to use it in temps below 70.

http://www.jgreer.com/

The stuff I used with no success was the west marine then again it turns out my part two was a funky red color later a friend told me it was bad.

I found this out after shaping and glassing two diffrent boards blowing both shaped blanks. The only saving grace was the blanks are ones I made from excess eps roofing material so they cost me nothing but time and gorilla glue. I wound up with two boards that = a goopy red gummy bear glass jobs.

3

Hi,

I’ll let the US guys who use RR give you the real story on that product, but in the mean time, here’s some things that you can check for errors.

Sometimes the mixing ratio is actually different if you are weighing it, as opposed to volume measuring.

For example, the Fibreglass Hawaii Aluzine stuff I was using when I was living in Santa Cruz is 2:1, but when mixing by WEIGHT, it is 100 parts to 40 parts, which of course is 2.5:1

That’s because the hardener weighs less per volume, so when weighing it, 2:1 by volume weighs 2.5:1.

That would account for a little bit of increased thickness in your mix, and definitely would make it set-up shitty, meaning delams… Check the label, see if they distinguish between weight and volume ratios.

If you feel you can glass a bit faster, I’d recommend the microwave trick - only put the resin portion in the microwave, before combining the two, and do 5 second zaps until it’s warmer and runny. Helps heaps, will soak into the cloth way faster. Speeds up pot life by a pretty un-quantifiable amount though!

Other than that, it doesn’t matter how long you mix epoxy if you are not mixing propery, which means scraping the sides and bottom of the mixing pots, sraping off your mixing stick, being really really thorough.

Every bit ya miss is a soft spot…

Anybody else? I don’t use that paint, or XPS, can’t think of any other probs.

Kit

4

BenR has some good points. Another thing to think about is to heat up your resin in your mixing cup in the microwave for a few seconds before using it. 60 degrees shounds a bit cold, and I’m not sure about glassing in anything colder than that. Additive F or xylene will help it flow better too. Epoxy is going to be thicker than poly, so try a harder squeegee. The yellow one is popular in this forum. There are lots of discussions on how to use epoxy on this site. Stick with it and don’t give up too soon.

If you can’t find video, PM me and I’ll try to set up a vid cam on a tripod the next time I lam. I’m not the best laminator in the world by far, so fair warning.

BTW - Did you give the paint time to dry?

5

I’ve had great luck with RR epoxy. I’m not that precise (I use metered buckets but often the scale starts at a amount greater than that which I’m using , so I eyeball the 2:1 ratio). I’m not surgical about being clean. I do mix thouroughly but not for four minutes like I’ve heard some people do. Never had a bad batch (I’m going to go now and knock on my wood board).

One thing I’ve notice on my most recent board (still in the process of being glassed) is that the residual hardener in my measuring bucket will turn a powdery white over night. I’ve been just wiping it off and reusing the bucket, so far no problems. I didn’t see this powdery effect on my last two boards though so I’m wondering if anyone else has seen this happen?

I can’t figure out what might be your problem. I glassed this past winter in 60-70 degree weather with no problems (LA area- dry). I got two shortboards out of 1 1/2 gallons with a little left over and a lot of waste (being a newbie I went generous on the amounts).

Maybe your cloth was damp?

6

While we are on the subject. Say you did a hotcoat on a board and there was a serious amount of fish eyes how would you go about fixing that?

7

I laminated, sand coated and finish (hot) coated my 6’4" XPS blank with RR Epoxy’s 3 pint kit. I could have used a little more and added one more sanding coat. I stuck to the Additive F recommendations and found the epoxy poured like water after a good mixing. It was amazingly easy to use and soaked into the glass just like Greg said it would.

You shouldn’t seal XPS. There is no need to, as it will not absorb H2O like EPS will. Steve Pirsch stopped me from sealing my XPS blank. In fact, he suggested I rough-up the foam in order to get a better physical bond. So far, so good.

I imagine that between the fine sanded blank and the krylon, your epoxy couldn’t bond well. Physically, that is. I’m sure that some members here are more “chemically” proficient than I, and have a better answer.

8
Quote:

While we are on the subject. Say you did a hotcoat on a board and there was a serious amount of fish eyes how would you go about fixing that?

cut out the fish eyes before you hotcoat… then with the brush, dab it into the holes where your fish eyes are so you can get all the resin in there…

as for the delamed boards, i think that maybe you should have gone over your art with a 220 grit to ensure that your glass attaches to the foam well…

also, i don’t know about the whole weight ratio thing so i stick to the normal 2:1 ratio… seems logical and like a lot less of a pain in the ass…

epoxy is thick and i would reccomend pushing that resin into that cloth as much as possible…

you have a 30 min grace period befor it starts to kick and gel so there is plenty of time to work things out

9
Quote:

One thing I’ve notice on my most recent board (still in the process of being glassed) is that the residual hardener in my measuring bucket will turn a powdery white over night.

I have the same thing happen when I have leavings in my cup. It seems kinda white and airy. Boards seem rock hard though. Glad I am not the only one. Wish I knew why.

10

The hardener does dry up on its own and turn white and powdery. Mine does that on the rim around the bottle if I don’t wipe it off after I pour. I don’t think it’s a problem as long as you’re not mixing it into your next batch.

I find it’s a lot easier to spread if you mix it for a while. I didn’t used to but now I stir for at least 5 minutes.

11

Yup, sounds like your batch wasn’t mixed well. Again, after 4-5 minutes of mixing, the epoxy becomes very fluid. I’ve never had to push it into the glass. I’ve found that the glass seems to absorb the stuff.

12

Hi ya all

Sounds like the hardener reacting to the moisture in the air

Epoxies don’t like any pollution

Greets Soul

13

There’s a lot of good advice (KR) for one on glassing. One thing that your not being informed on is the fact that when you shape with XPS don’t leave it with a fine screen finish. After I am done shaping with my screens I do one last pass with 60 grit Klingspor (Cloth backed) broken-in (soften) sheet. I pass over the entire board including the rails. The surface is almost a little hairy. Most of my production is XPS and I have no delams. I can’t mention his name here however a 35 year vetern shaper shaped one of my xps blanks and left it smooth as a babies butt and rode unreal. However it delamed and was repaired 3 different times. I finally convinced him to do the 60 grit sand pass. I think he uses 80 grit on the last pass. He has done 20 xps boards this way and they are delam free. One more thing to think about is the stringer in the blank. If the XPS surface is not sanded before gluing you will have gassing problems along the stringer line.

Many glassers blame the resin which sometimes it is. Shapers and Blank builders are also responsible or should be?

Hope this helps?

14
Quote:

There’s a lot of good advice (KR) for one on glassing. One thing that your not being informed on is the fact that when you shape with XPS don’t leave it with a fine screen finish. After I am done shaping with my screens I do one last pass with 60 grit Klingspor (Cloth backed) broken-in (soften) sheet. I pass over the entire board including the rails. The surface is almost a little hairy. Most of my production is XPS and I have no delams. I can’t mention his name here however a 35 year vetern shaper shaped one of my xps blanks and left it smooth as a babies butt and rode unreal. However it delamed and was repaired 3 different times. I finally convinced him to do the 60 grit sand pass. I think he uses 80 grit on the last pass. He has done 20 xps boards this way and they are delam free. One more thing to think about is the stringer in the blank. If the XPS surface is not sanded before gluing you will have gassing problems along the stringer line.

Many glassers blame the resin which sometimes it is. Shapers and Blank builders are also responsible or should be?

Hope this helps?

Correction to my post: The good advice on glassing was from (KK) not (KR)

15
Quote:

You shouldn’t seal XPS. There is no need to, as it will not absorb H2O like EPS will. Steve Pirsch stopped me from sealing my XPS blank. In fact, he suggested I rough-up the foam in order to get a better physical bond. So far, so good.

I saw Steve the other day and he’s riding those boaty twin-cutaway-finned XPS boards exclusively and they look highly bulletproof. He was having fun in some real crappy surf. He is ALWAYS having fun in Texas surf. You should seee his boards.

Steve Pirsch is rad.

16

hi ,all the answers are good ,one other thing i do sometimes if its cold here is even after warming the resin i use a hair dryer to keep the resin fluid while i am moving it around with trhe squegee, if the resin is thick it just traps air and eventually it turns whiteish and doesn/t soak in to the cloth so good ,

its all experiance ,we have all learned by our mistakes on here, your next ione will be better, pete