I’m trying to finish my first board economically but I don’t want to ruin the glass-job with substandard materials. I’m curious about the differences between epoxies. What brands have you tried that worked and/or didn’t work? Was there a marked difference between that and others? I figure I can go with whatever Greenlight surf supply offers that I know is tried and true, or I can risk saving some money on a 1:1 “bar-top, marine, casting, etc.” epoxy for considerably less money from Amazon. It’s really hard to find some reliable information on the internet and first-hand experiences would probably be the most helpful.
I have been happy with Resin Research KK and Greenroom Old #7.
I would suggest getting surfboard-ready materials (resin and cloth).
They will be easier to use and have more clarity and UV resistance than their industrial counterparts.
Once you get the hang of it, go forth and experiment.
if you want to use a cheaper alternative, use polyester. If your going to do epoxy use the best as its hard enough with a good product. Kinetix and Entropy are the best that I’ve used
Don’t go with that bartop stuff, I’ve heard it isn’t UV stable. It might yellow and turn brittle.
The bartop stuff is also thick as all getout. Not the best thing to learn with. If you’re in the USA, go with RR or Greenroom.
Like others I’d recommend avoiding bartop epoxies.
BUdget wise, I use Apex Epoxy from surfsupply/fiberglass source. 85$ for 1.5 gallons but I see they now have smaller kits too. They also sell another label for same price they call Prolink.
Mix resin/hardeners ratios precisely by volume or weight, Mix thoroughly, meaning the sides of the cup and the mixing stick, and avoid surface contamination or fallout contamination( dust). A lot of Newbs to epoxy seem to not understand the required precision of the mixing ratios, and thoroughness with with it must be mixed together, then blame the epoxy for not being as forgiving as Polyester.
Mix it until there are no ‘Swirlies’ visible under a strong light, then mix it some more.
My favorite epoxies have been from System3, but they are not budget, and not always intended for lamination of fabrics. I’ve not yet tried their newest ‘silvertip’ lineup, nor have I tried any other of the surfboard specific epoxies listed above, for comparison. I like the System3 Clearcoat resin for penetration and lamination but not hot/fill coating, but it is SLOW, not production friendly, and that slow allows more time for fallout to affect it, but I was basically unaware of ‘fisheyes’ until I used that first batch of Apex epoxy. Seems their latest batch with the more clear hardener is better at resisting the desire to fisheye and have me launch tools into low earth orbit followed by a burst of vile curses.
If I recall correctly you’re the guy in Idaho and you’re working on an EPS blank. If so then you can’t use polyester.
As a beginner you will probably need a 1.5 gallon kit . You could do it with half that if you don’t have any waste but that’s not an assumption I’d make for someone who has never done any kind of glassing.
The trick with economizing with glassing is to avoid waste. As a garage hack here are a couple steps I take to reduce my waste:
First off, start clean. Don’t ever plan on covering up mistakes in your shape with your glassing. That basically never works. Pay particular attention to getting your stringer flush with the foam. If the stringer stands up then that’s where you’ll have problems with both sanding and structural integrity of the finished board.
Forget what you’re seeing the pros do on the how-to vids when they’re glassing a side in 8 minutes. They’re in the groove and have refined their technique over hundreds and thousands of boards. You’re not there yet, so you need a process that’s geared to your speed and technique.
Finish sand your blank and blow it off to get all the dust off. If you leave any dust on the blank it will interfere with the adhesion of any masking tape you’re using.
When you lay your masking tape, lay if flat and press it down really well so that nothing will seep in under it. If your tape doesn’t lay flat you’ll get bleed through (ask me how I know). Use good quality masking tape from the auto paint supply places. Save the cheap masking tape for non-critical areas.
Use vinegar to clean up. It’s a fraction of the cost of denatured alcohol or acetone (which you shouldn’t be using acetone with epoxy anyway). You might as well use cheap disposable brushes and just throw them away after you use them once. Don’t even bother with cleaning them.
Buy a $20 digital kitchen scale from Target or Wal-Mart and measure your resins by weight. Buy a 6-pak of cheap scissors from the 99c store and plan of throwing them away when they get resin on them.
If you’re measuring by weight then you don’t need any other type of measuring marks on your cups or measuring dispensers from your resin supplier. You can buy a sleeve of 9oz plastic cups for $.05 each, and you can reuse some of those cups for your small batches you mix for ding repairs and the like. Don’t spend $1/ea on marked plastic measuring cups from the home improvement store - that’s just wasting money.
Get some wooden paint stirrers and cut them in half. You can use these with your little plastic cups, and the square shape is easy to clean when you’re finished (I normally just wipe them off with a paper towel). Being short, they won’t tip the cup over if you set it down with the stick in it.
Only mix as much resin as you think you’ll actually use. If you’re doing a leash plug install you only need 15 or 20 grams of resin, and the only way to reliably and accurately measure that small an amount by the correct ratios is by weight.
Work in small amounts on small areas. If you’re glassing your first board then don’t try to mix all the resin for one side at one time because you’ll have problems getting it all spread out and your laps cleaned up before the resin sets up. Instead, mix small amounts - like 145 grams at a time. Spread the first batch on the flats and up the middle, but not onto your laps . Then mix another 145 gram batch and work on one side of your stripe, then mix another batch for the other side of the stripe and see where you’re at. If you save your laps for last you won’t run out of time with your resin and you won’t be wasting a lot dripping onto the floor.
Cut the straggly threads off the laps before you attempt to wrap them around your rail. They’ll be a hassle if you don’t.
When you’re doing your finish coats, plan on doing at least 2 lighter layers over your lamination (and maybe more) instead of the one heavier layer the pros do. You want just enough resin to completely fill in the weave. Any more that that is just excessive and will force you to sand more.
For your first couple boards, put your board into the racks vertically so just one rail is exposed. Tape your lap line off on deck and bottom, and then glass the exposed rail by itself - plan on 2 thin coats, and don’t let any runs onto the flats. Since you’re glassing the entire exposed rail you’ll get good smooth coverage without a tape line on the apex of the rail that occurs when you glass the board flat. it’ll be easier to sand. Then you can tape the rails off when you glass the flats and limit any overlap to the flat areas that are easier to sand.
When you sand, only use a sander on the flats when you start sanding, and then only take it down to about 90% where there are still some shinys. Do the rest by hand with a sanding block (like a 1" thick piece of wood or EPS) , and ALWAYS use long strokes from nose to tail. You really only need to sand to about 120grit or so to get a finish you can surf. Going beyond that is mostly cosmetics.
Years ago I got a 7 gallon kit from a guy making surfboards here and the label said composite polymer design or something like it. It was really good, sanded better than any other epoxy I’ve used. I think the product is sold through Endurance Technologies and MAS epoxies now.
Also check the epoxy XTR sells.
These days I use Fiberglass Hawaii Aluzine because it the easiest to purchase.
The 1:1 gloss stuff should only be used as a finish coat. It takes many hours to cure, so you need a clean room with no air movement. I used that once and it came out shiny and smooth. It was still tacky several hours after applying. I would not recommend using it even for the final gloss.
Good post, but may I add a couple of thoughts.
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Don’t blow off the blank. Air compressor air is dirty, full of water dirt and oil. Wipe with a microfiber cloth.
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Don’t use the throw away brushes. Purde Nylox brush instead. After use, clean them with a brush comb. First with vinegar, then with xylene, then acetone. No more loose bristles in the coat, and a good soft brush lays it down like glass.
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Squeegee the first epoxy. Scrape it around. That gets rid of fish eyes. Then right away mix up your main batch. I typically hot coat with 250 grams of epoxy to 100 grams hardener
Use absurfboard specific resin for clarity and UV resistance. I’ve had my best results with RR Kwikl Kik. I use ProLink pre pigmented on my carbon boards.
RR has been there from the beginning and has always been the benchmark. They keep improving.
All the best
Vacuum (suction) is a common method for removing dust without blowing. The air is as clean as what is in your shaping or glassing room.
You can follow vacuum with a residue-free wipe.
You really don’t want to vacuum a shaped blank. You’ll end up gouging the foam.
2 words : resin research
P.S.
I blow the dust off with a leaf blower
Depends on the attachment you use.
Show us one of your boards Mr Stoneburner. You’re highly opinionated for someone who’s never posted up a shape.
How do you remove foam dust after sanding?
My comment is/was not an opinion.
Accept. Reject. It does not affect me.
Out of all this epoxy mumbo jumbo all I can see is a guy putting his blank on the floor and running a vacuum over it like he’s cleaning the carpet.
So good! Haha.
Upright? Hoover or Dysan?
I use my trusty mid 1980s Kirby bought it used about 8 years ago.
And it still sucks.
I’m totally visualizing the entire blank flying off the racks. And yes, Resin Research is good.