The following are tips and such that I found that others might appreciate when working with epoxy. This comes after two boards of epoxy experience, so if its not totally correct feel free to comment.
RULE 1:ALWAYS glass in suggested temperatures. 5 degrees can make a difference. I glassed a little over a month ago and just finished fixing that goof up all because I glassed in 55 degree weather.
RULE 2: MIX CAT & EPOXY GOOD! Probably something else that contributed to my one-month goof up.
TIP: Tape off for both hotcoats. Sanding will go much easier if you do this…
TIP: Don’t wait too long to pull tape.
TIP: for fin panels, try a roller (the type used for painting) with a squeege-type head. I found it alot easier to move the epoxy over the panels instead of a brush…
TIP: Buy an electric sander… I didnt and I’m sorry I made that decision.
But all in all, Greg’s stuff works better that I first thought, it’s just really temp sensitive… But the down time here at swaylocks gave me a chance to get caught up with everything… still a great site, just a new look!
PS: hope to post pics soon of the two epoxy boards, there’s a huge diff. in my first and second attempts. Maybe after this weekend, following a trip to ponce/NSB
You all are probably way ahead of me on this, but I’ve found that wetting the laps with epoxy is so easy when you do this:
reach underneath and from behind and take the dry lap in your gloved hand then pull the epoxy down from the rail and smear it on. I had at first attempted to let it run down over the edge of the board and on to the lap, but that was such a waste of epoxy and still left dry areas. Now my laps are soaked and easily adhere to the bottom of the board.
In one month I am going to start a board using epoxy for the first time- I’m a little anxious. Your temperature comment is somewhat unsettling. I’m shaping on the East Coast where weather is either hot, cold, humid or wet. Will this cause severe frustration, which leads into neurosis.
Okay, I have some questions regarding epoxy laminating. i have seen a few posters now say that you have to wet the laps by hand unlike poly where you can squeegee the resin over the rails and let it drip off into a big mess to wet the laps.
how about wetting the flats out? Many have said that if you squeegee like poly the resin will froth. So how do you push the stuff around and how to you squeegee off the excess without it getting frothy? Also do you need to sand before the hotcoat and if so how much do you sand for a good hotcoat without weave showing?
Greg, I use the same method. It saves a lot of wasted resin.
As for the froth thing, you slowly pull the resin from the center out toward the rails using a hard plastic spreader. You have lots of time to do this and the epoxy soaks into the cloth, even over 3 layers of 6 oz. For the excess you slowly pull it off the flats and you will not get froth. You can sand before the hotcoat to insure a no weave result but it is not necessary if you are careful with the sander.
I agree on the laps. I use the same method and it works well. I’m no Greg Loehr and so far don’t have access to his resin in New Zealand. Not many board makers using epoxy around here but lots of boat builders. I use a pretty standard boat builders epoxy. I use a fast set hardener for the lam to minimize the soak into the foam. I do get some pin holes occasionally from working it too much. Then I use a slow set for the hot coat and it mostly seems to seal any pin holes. You do get the odd bug from the long set up time. Ah well bugs are cool. I don’t stress too much about the air temp though it’s pretty mild here generally. But… I do finish with epoxy primer and paint with linear polyurethane paint. A few extra steps. And the paint isn’t cheap but it’s super tough. Just the way I learned. Good luck.
Hey fluffy, Also being in Ga. I can relate to the temperature thing. One thing I do is to heat the Epoxy in a micro wave for about 20-30 seconds before use. This will make it really liquid and it just flows though the cloth much easier. It also allows me to glass in lower temps. Stop by and say high next time your on Tybee, I’m opening a resale shop Apr 1. Underground Boardworks, 1213 E Hwy 80. See ya, Tuna (formerly know as Harry Balsak)
i bake my board as well and glass it hot that way the resin stays viscous the whole time your working…and sucks the resin in avoids blow outs…
also the frothy thing is not with all epoxies …some stay clear as ,right to the end …and others turn to bubble bath,you just have to find the right brand…
Tuna, thanks for the microwave tip, i’ll have to stop by sometime… its just hard to commit to GA surf… I dont want to scare people out of epoxy, just be sure to follow directions. Also, allow yourself one “practice” board. But I’ll def. be trying the microwave. Gotta pack… fluffy.
I’ve glassed in 55¼ with no problem. What probably happened was when you finished glassing in 55¼ you then left the shop and the temperature then fell from there. All thermoset resins have temperature issues and ours certainly is no different. The simple way to eliminate these issues is to heat a work area. Keep things around 65 to 70 and everything will work great, this includes the curing time. And the boards come out better too. On the frothing, we had a choice we made a long time ago. As Bert said, some epoxies don’t froth and we seriously worked on formulas that didn’t. The problem we ran into was that those resins are not very reactive. This means to make the resin reasonable, speedwise, we had to increase the reativity of the hardener. This caused the system, overall, to be MUCH more toxic. The froth issue is simple todeal with using the techniques mentioned above. We didn’t see the point in raising toxicity for such a minor issue.
RE the froth issue, you can use more resin and not have to spread it around as much and avoid the froth. But I’m looking to play to the strengths of epoxy and build the lightest strongest board possible. That requires pulling as much resin off the board as possible during laminating and getting the cloth to bond as tight and close to the blank as possible. So I have no complaints about a little froth if I get in a hurry. As besides, while I don’t know how far I want to take this, air-entraned resin (ie froth) ought to be lighter per unit volume, albiet, marginally so.
Jong and GregT, have you thought about priming the blank with a microballoon slurry before laminating? Helps with glass/foam adhesion and allows you to sweegee off all excess resin and pull the cloth tighter onto the blank. An experienced hand will get close to vacuum weights. Although there have been critics of this technique in this forum in the past, it is an aeronautically accepted standard and highly recommended for saving weight, gaining strength and ensuring bonding.
Thanks Dale, interesting article. I guess my reference is to the part on filling the cells. Surfboard foam is actually very high quality and quite dense compared to some crap I’ve worked with, and filling is probably not actually necessary. I must say though, I achieved much better results by doing it, and would recommend it as an extra step in the direction of better quality, not only in strength and weight, but in a tighter reproduction of the original form. Not all shapers out there shape boards with allowance for the various laminate thicknesses, and I don’t blame them. After all, it’s only a surfboard.
Resin pumps. They only cost a few dollars each and its in the interests of our health that we don’t go dripping it anywhere
electronic weighing scales will allow successful measuring of smaller quantities of resin - useful for doing smaller jobs such as fin boxes. Accurately measuring small quantities of epoxy is one of the difficulites with working with this resin.
This one is for the neurotic board builder. Try and have a mixing system which avoids the following scenarios which i have gone through:
a) Stare at the rather similar looking 2 containers of epoxy and wonder if i really did mix up part A and B or whether i accidentally added two lots of A. Decide to throw away mixture and not risk wrecking project only to find it sets fine.
b) Stare at the rather similar looking 2 containers of epoxy… same as above but decide to go ahead with lam anyway and then spend 1 hr worrying if it is going to set.
