I recently did some board repairs to an Pearson epoxy paddleboard and this was my first experience using epoxy resin. I worked outside in the sun in 75 degree weather and mixed the resin and hardener in exactly the proportions prescribed. The gel time surprised me. First off, there appeared to be no reaction at all for at least 30 minutes and then a slight thickening began after about 45 minutes or so. The mixture seemed as if it would still be workable well after one hour. The board repairs were major and thse properties were observed in two separate repair “sessions” two questions: 1) Does this seem normal? I would love to think I could have the luxury of an hour to glass my next board. 2) If I made my next board using epoxy resin, will this be incompatible in any way with the clark blank and 4oz “s” cloth I have already purchased? Any other incompatibilities or difficulaties? Thanks!
- Yes. Epoxy doesn’t do the sudden gel that polyester does, it just seems to get thicker and thicker, then harder and harder in a slow process. Actual workable time will vary by system and hardener choice. If you keep a large quantity in a bucket it will get hard faster tho. 2) No. Epoxy is compatible with PU foam and normal glassfiber cloth normally used with polyester resin. In addition it’s also compatible with polystyrene cores. Don’t work the epoxy resin too much, if you do it might froth(sp?). Instead just spread it out evenly on the glass and let it soak in. Remember, you have plenty of time. There are quite alot of info in the archives about epoxy too. regards, Håvard
Epoxies really vary a great deal with respect to how they harden, pot life and cure time. You can’t vary it with more or less hardener the way you can with polyester resins; instead you have to mix the precise amounts the manufacturer specifies and kinda bear with it. Some makers have optional fast and slow hardeners which you can use to speed or slow cure time - check with the folks who madce the resin you use. I have used System Three resins and RAKA resins with good results. Beware of resins that yellow in the sun or that have what’s called an ‘amine blush’. hope that helps doc
Type “Greg Loehr” in the search box and read up on what he’s posted. You’ll find answers to all your questions. Then call him and order up.
Or you can e-mail me direct with any questions. Here is some info I put on swaylocks a while ago that might help: Below I’m writing some tips on making our stuff easier to use. If you take your time epoxy is actually easier to laminate than polyester, uses much less material and eliminates harmful chemicals in the factory. 1. Mix ratio must be adhered to. Deviation from the mix ratio will keep the resin from attaining a full cure. Also the material must be THOROUGHLY mixed. If not there can be soft spots. We use metered buckets (I’m sending you one which we get at the local hardware store) to assure proper mix. We use large paint stir sticks (like the ones hardware stores give you to stir paint). All our resins are 2 to 1 mix ratio by volume. The metered buckets work unreal, actually better than pumps and we laminate right out of those buckets. 2. Additive F. We use it in every batch we shoot, including laminates. It eliminates blush which is the biggest problem in building epoxy boards. It only takes 1cc per ounce of hardener in the mix. We put it in after pouring the resin and hardener into the bucket and then mix them all at once. It makes the resin a bit cloudy but clears out when the resin cures. 3. When laminating, the first thing to do is to pour all the resin out and spread it over the glass. You then wet the rails and tuck them. This gives the resin time to soak into the cloth on the flats. Polyester must be pushed through the cloth. Epoxy just soaks in and it does that in its own good time. It can’t and shouldn’t be forced. Additive F actually helps with this quite a bit. After it soaks in, squeegee out any air and remove any excess. We use plastic, “spreader,” type squeegees. We’ve found that they move epoxy better than rubber squeegees do. They take a couple boards to get wired but after the initial learning curve laminating is much easier. 4. We use VERY little resin. Below is an example of our use levels for different size boards. As there is no “gel” time, any resin left over can be used on the next board. If you run short you can easily mix up additional resin to finish with. Usually we just work out of one bucket and simply keep mixing more material as needed. It isn’t the same, “this bucket for this board,” as polyester. These are estimates for total mixed material. 6’ and under - 9 -12 oz. bottom 12-15oz. deck 7’ and under - 12 -15oz bottom 15-18 oz. deck 8’ and under - 18 - 21 oz bottom 21- 24 oz. deck 9’ and under - 24 - 27 oz bottom 27- 33 oz deck Hot coats run just a bit more than an ounce per foot. For instance a 6’ board would take about 7 oz. per side. Longboards, 9’, take about 12-15 oz. per side. If your glossing use a bit less than a hot coat. We use 3" disposable white bristle brushes for hot coating. We don’t clean them. We use them for one batch and pitch em. Not only do we feel that their not worth cleaning but we’ve also had problems in the past with contamination from cleaned brushes which manifested itself in bad hot coats. New brushes always make for clean hot coats. 5. Do not use acetone for clean up and never let contaminated acetone touch the skin. Any toxicity problems we’ve seen in the past always included contaminated acetone. Not only that but acetone doesn’t work that well with epoxy anyway. Leaves everything sticky. For your hands use disposable vinyl gloves. Clean gloves between boards with scrap fiberglass. I usually cut scrap and pile it neatly on the table so I have plenty ready. Clean your squeegee with scrap glass. Anytime the squeegee gets slick I just wipe it and my gloves down. When the gloves get funky, peel em off and put on a new pair. 10 cents a pair is cheaper than acetone. With so little resin being used very little goes anywhere except on the board so things tend to stay much cleaner. We don’t ever get more than a drop or two on us. If you do get some on you, use Go-Jo or Fast Orange or some other waterless cleaner with water to get it off. These clean epoxy more effectively and are much safer to use than acetone. I think that’s it. You shouldn’t have any problems but if you do my phone number is on the bottle. I also have a cell # 321-223-5276 which I usually have with me always.