Is there a test to tell when you have removed the film formed by the epoxy curing? Some of you call it a blush. I have read I can remove it with alcohol, acetone and other wax cutting cleaners. I have been told to remove by cleaning with one of the methods above but not how to clean it. Do I wipe it? Do I scrub it with a sponge or Scoth Brite? Do I scrub and wipe it with a lint free cloth afterwards? Do I sand and wipe it? How do I test it to see if I have removed any residue so I get a proper bond between the epoxy and polyester? Thank for your time and comments.
You can’t always see it. If it’s milky-white or if it still feels wet - not like wet (soft, sticky) resin, but like water - after more than 24 hours, just wash it off with a hose. You’ll see it washing off, like soap from a car. At that point, it won’t affect the cure - its done. Just make sure to get all the water off before the next step.
Dry with towels, wipe with denatured alcohol, rough up a little, and warm up your resin to hotcoat…
Thanks for the reply, We post cured the epoxy hot coat in the oven at 125°F, a lot of Epoxy ran off the board. The quarter size drips were covered with a slippery clear film the next day when they were hard. They were wiped with alcohol and they were not slippery anymore. They had a lot of drag to them. Is this what I will find with the sanding process. Will this drag create the heat that will soften the Epoxy and make it gum up the sand paper? I have read a lot of posts on this site and I am experiencing the results very quickly.
I also want to install some FCS fins in the three boards. The one Styro board needs Epoxy to set them. Is there a problem waiting to happen I should know about. Any suggestions will help before Saturday. Again thanks for all your help in a new field for me.
Howzit NY, Be very careful installing FCS in styro, it has a tendency to melt the foam. In fact Rick Holt was by yesterday and was telling me about a disaster that happened to him doing a FCS install in styro. He said the foam melted big time and sounded like it basically ruined the board. I don’t do epoxy boards but it seems that you would need to do a really slow kick off batch to prevent this from happening to you. Ask some of the epoxy experts about this one before you make the leap.Aloha,Kokua
Thanks for the heads up. I think I will put some ziplock bags filled with water under the bottoms side of the deck so it stays cool. Hope this works. Any suggestions from those who have done this before. I do not need a major problem at this point. I am happy it is only one board that is Styro.
aNY- Take the bumps (drips?) down with a surform. Its faster anyway, plus it doesn’t heat like a sander. If you get soft areas, hit them with a cabinet scraper.
For your box installs you have a few choices.
You can cut out oversize holes, glue (gorilla or so) in high-density foam or balsa or something. I even used Clark rail offcut pieces once - worked great. Then, plane smooth, and route again to your box tolerances.
You can chill everything - resin, board, air, boxes - to buy some time.
You can use a slower hardener & a lot of chopped glass or microballoons - both of which will absorb quite a bit of heat.
I mostly just route holes to VERY tight tolerance & then use pieces of glass cloth under & around the boxes. That’s perfect for 2# EPS, but 1# needs one of the above forms - or some combination you think up yourself - of extra consideration…
System Three states you can bond Polyester to their SB-112 Epoxy. It might be a no no but it is part of the process I wanted to do and learn from. I will finish the glassing and hot coat them with PE this week. I will set the fins this weekend. Something new to learn again. I have read a lot of posts on this site since last spring to learn how to make a surf board. I decided to build three boards for my trip to Costa Rica this winter to try out. One was going to be an Epoxy so I can try the new stuff but later I decided it would be to hard to learn the first time round. Because of Clark Foams’ closing I lost an order I paid for in advance and had to scramble to get only two Clark blanks. The other ended up being Epoxy by default. Both 8’-1" by 23" wide boards are wider versions of the McCoy Nugget I own. The Epoxy is 3-1/4" thick and the PU is 2-3/4" thick. Both have the same rocker and bottom shape as the Nugget but wider by 1-3/4". I am using various glasses on the boards to see how well they last and where they fail, The flex and non flex feelings between the boards. This is a experiment to see how the changes I made will change the boards responses in the same surf. This way I know what to expect and change in my future projects. The third board is a 9’ long 23-1/4’ wide by 3-1/4" thick with a 18" concave nose and 15" round pintail with vee in the tail. A 3-5/8’ nose rocker and a 3" tail rocker. The deck is laid up with a carbon/kevlar with a 1-3/4" lap. covered in 2 oz fiberglas. The bottom is one layer of 4 oz S-glass with a layer of 2 oz on top of it. I will post the pictures as soon as I learn how to post them. I will have to reduce the size to do this. Any way I am doing a no no but I will let you know how it turns out. Thanks for you response.
The FCS plugs are cut into the board in a circular H pattern. The bottom of the H reaches the underside of the deck. This gives it strength. The concerns I have are with the center of the H between the plug and the cylinder of foam that is attached to the underside of the deck. If i clean out to much of that cylinder it will create a large void for the Epoxy to build up heat. I have to find a way to keep that heat to a manageable temp where it will not melt the Styro. As you mentioned the Styro will act as an insulator. Thanks for your post.
Howzit NY, You definitly want to cool the deck where the H pattern connects to the deck. If you don’t you will get indented circles where the H pattern is and when you sand the board the raised section in the middle of the H pattern will get sanded more and make it weaker. That was one problem with using the FCS premix resin they sold a couple of years back, it was to thin and if you were glossing the board you had to sand to much off the deck to get rid of the shine where the H pattern indents were. Hope you understand what I trying to say. Like I said before, big sponges fully wet with cold water seems to keep the deck area flatter and easier to sand. What might even be better with epoxy would be to fill a trash can with about 2 feet of water, the area won’t get to hot until the epoxy kicks and by then water shouldn’t affect it so as soon as the epoxy kicks off just put the tail of the board in the can so the water is above the plugs. This just popped into my head so it’s just a theory but I think it will work.Aloha,Kokua
Thanks for the tips. I think I will stick with the wet sponge of water filled ziplock bags. I am lucky I only have to do one board in Epoxy. Tthe other two can be PE. If things go well the next two nights we will be on schedule to install the fin boxes on Saturday. I have a mac and am not sure if Microsoft’s program will do what I want. I think i-photo should be able to do it as well. I have to find the time to do this. Maybe one day this weekend. Again thanks for the advice and I understand about the “H” pattern. The question is how do you make sure you do not remove the EPS cylinder core by accident? Wish me luck.
Howzit NY, Do you have the FCS installation kit and install manual or are you just winging it. Never had any problems with the foam cylinder core when installing. Aloha,Kokua
I have read the installation manual a few times and understand what I have to do. I purchased the whole kit with the drill bits and all the other tools and parts. It will be the first time I will install a FCS plugs and Fins Unlimited box. My friend who is helping me has seen them installed before so he will be directing me as i go if I start to do something wrong. We made a small sample Styro core with Epoxy laminate and hot coat to see how it dealt with the heat of the oven. Some problems but it is still intact and will be used as a test mule for the FCS system and epoxy. I will see how hot it gets and also see how well the “H” pattern works for the Styro.
We finished glassing the decks tonight and did the first hot coat. It is the first time in the project we are a head of schedule. This will give me time to test out the kit on the test mule before we do the real one. I will let you know how it goes.
I think the FCS fin system needs the stiffness of the Epoxy or polyester to work as a support from the under side of the deck. I am not sure the 3m 5200 will be stiff after it is set. Thanks for the tip. When I am in the hardware store next time I will look for it and read the label and see if it dries to a hard state. Thanks for the tip.
Hey Tim, when i do my boards (all EPS/SB112) i put in red x boxes and use an epoxy glue mixed with some milled fiberglass rather than a laminating epoxy.
I personally use Industrial Formulators G2 epoxy glue. i have never had any problems with excessive heating.No need to cool resin or boards or anything out of the ordinary. (I think some people really make things a little more complicated than they need to be, but hey maybe their finished product comes out perfect)it is a little thick and takes a while to fill the holes but cures fine, still has a slow cure time (24 hours) and you need to add a little extra white pigment as the glues tend to be quite yellow.