As near as I can tell, the only advantage polyester has over epoxy is that it can be UV cured, which speeds up the glassing process and reduces waste. I know the chemistry exists to a limited extent, which has me wondering if there’s a chance we’ll see a laminating epoxy that’s UV curable anytime soon.
I know it exists. Electronics companies use uv cure epoxy to make parts and seal circut boards. A friend of mine looked into buying some but I think it was really expensive. I would love to see it for making surfboards though
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As near as I can tell, the only advantage polyester has over epoxy is that it can be UV cured, which speeds up the glassing process and reduces waste. I know the chemistry exists to a limited extent, which has me wondering if there's a chance we'll see a laminating epoxy that's UV curable anytime soon.
The chemistry is different, the UV curing epoxies don’t share the mechanical properties of the common epoxies used for surfboards.
The way to speed things up is to use a fast pot life epoxy and an oven. Resin Research epoxy comes with its fastest hardener (20 min pot life), stuff it in a 90+ degree oven, and it will be done quite fast. So, I think glass shops would need ovens or hot rooms instead of UV beds.
When we look at what makes poly cure and what makes epoxy cure it’s clear we have two very different animals. Ploy is about catalyzation. Epoxy is about the hardener working with the resin and temperature is what determines how fast it happens. For both materials direct sunshine on a warm cloudless day works grand as it delivers both elements necessary for curing. Everyone using Poly is stuck on UV cure and for this type of resin you can’t beat it but there’s no reason to try and make epoxy work like poly IMHO. The issue with epoxy and putting it in an over is the possibility of creating off-gasing from the blank, which obviously would not be good. However once the material begins to thicken I wonder if it remains an issue? If this hardening process starts in about 20 minutes your really in just as good a shape as you would be with UV poly except of course you’re working against a cure deadline like you woule be with catalyzed poly. An oven at about 90 to 95 degrees certainly would accelerate bringing the board to a workable hardness. With a little experimentation to determine the proper size and concentration of bulbs, panels of incandescent lighting spaced nicely would deliver a proper amount of heat and make the standard uv poly oven into a one that would work for either chemistry with one switch for uv florescent and one for incandescent.
Just food for thought ~~ anybody think it’s worth a try?
Good Waves, Rich
i really hope that someone soon will invent uv epoxy and sell it at a reasonable price
that will be the day
i heard that they sell uv epoxy at surfsource but it is very expensive
ive had this happen to me twice. I had a newly mixed bottle of epoxy resin ready for
some boards; i set the bottle down and it was being hit by direct hot sunlight;
instantly it started smoking a bunch and then hardened in less than a minute; it is
definetly a weird thing to experience - the entire 16 oz hardened in less than a
minute; harder than concrete - it also ate the plastic buket it was in
Most of the UV epoxies being produced today are generally being used in pharmaceuticals. This is where a lot of technology starts off and then it moves into industry. It just happens to be VERY expensive at the pharmaceutical level. Much of this is being used in dentistry right now which is pretty much where the whole UV resins thing got started … well that and in inks. I’ve worked on this a bit and where I really see this being useful is in hot coats.
As for heat curing, after about 45 minutes or so our fast can then be put into a hot box and cured the rest of the way. This provides a sandable surface in about an hour and a half and the off gassing Halcyon mentioned isn’t an issue. Not quite as fast as UV cures but reasonable for production.
Greg,
I was hoping to hear your input on this. I don’t want to soung like I’m short-changing everything you’ve done to bring epoxy to it’s current user-friendliness and durability. It’s just that, as an amateur glasser, UV curing saves me a lot of headaches and allows me to get a board glassed pretty quickly. As an amateur wannabe chemist, I wondered if wouldn’t be possible to mix the epoxy with some sort of inhibitor to prevent the cure until exposed to UV. Kind of the opposite of what I think happens with UV poly.
There are UV cure epoxies out there based on acrylate chemistry. I haven’t checked recently but last time I did everything was still pretty pricey. There are also some acrylic resin coming out that have some nice features that can be UV cured, but again, pricey right now.
I know that everyone likes to hurry, I do to sometimes but two days to make a board still seems reasonable to me. Especially when it lasts twice as long.