Hey y'all,

We just spent a few days in my shop with Greg Loehr of Resin Research. He's been making leading-edge epoxies for the surfboard industry for the last three decades and has some products that blow my mind. Greg's 2040 is a very low-toxicity, extremely resilient resin that is outperforming WEST by a mile. Here's a goofy write-up I did of our highly scientific tests.


One of Greg's great demonstrations is a series of samples of fiberglass cloth with each of his for resins laid up on a styrofoam sheet. His hardest resin is comparable to WEST for brittleness. His most resilient resin with the highest amount of plasticizer, called 2040, is the other extreme. Pushing a screwdriver into the hard one (or WEST--we tried that too) gives way quickly with a resounding snap. As you move toward the more resilient resins, it gets harder and harder to push through. The 2040 is amazingly tough. We did a lay-up of toilet paper and 2040 and it was quite a bit tougher than WEST with fiberglass. Seriously. 

We shattered some fillet joints in our tests. The WEST explodes into a zillion pieces. The 2040 either tears the substrate apart, or simply breaks in one place if there is no alternative. You guys really ought to get a batch of this and see if you like it. I am blown away and switching over pronto. I used the last of my WEST up in the tests and don't reckon I'll get any more.

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Really Cool, Great post and article...I love new materials. Any idea how it performs in conjunction with other fabrics like Kevlar or carbon fibers? JG

As I understand it, carbon fiber is something you'd want to use for extremely rigid layups, and matches up with a very rigid epoxy, like WEST or the Resin Research 1980. The fabric Greg Loehr recommended for a more resilient layup would be Xynole or Dynel. Kevlar is good for bulletproof vests, but not that good for boats.


I am supprised I have never come accross this resin in the past few years since I am always looking.  I have a need for a resin and fabric to be used on some flexible membranes.  This might be the stuff I need.  

Do you have sources for Dynel fabric and tape?

Your comment about Kevlar is an interesting one.  While some of it's properties get in the way of fabrication and repairability the stuff is very strong.  After using a bunch I am still a bit undecided as to my long term use of the material.   In many ways biaxial glass is difficult to outperform when we factor in the price.  The added weight is not that big of a problem.

As for Resin Research, are they a chemical company?  Most building block resins come from the big name companies like Huntsman.   I don't know where Raka gets their resin but I am sure all the do is blending and distribute.  I know almost nothing about West but I would suspect the same.  Cracking hydrocarbons and reassembling them is not something most small companies can do.

While I don't suggest people use unsafe practices with large amounts of VOC solvents, formaldehyde and acetone are from natures kitchen.  Over the years I have tried many "water based" finishes and adhesives.  I got burned and wasted a bunch money on water based contact cement as well as water based veneer glue.  The contact cement was a total bust and the veneer glue only lasted a few years.  Good old hide and PVA are good for a hundred years or more.  I am all for safe materials but they need be proven to work.

Anyway thanks for informing us of these resins.


Defender Marine has Dynel and Xynole. The idea is you don't want to use a flexible fabric with a stiff resin and visa versa. They need to be compatable. Greg is a fan of Xynole, Dynel, regular glass, biaxial, and CoreMat.

The layup we did with his 2040 and biaxial was crazy strong. I have ordered some samples of Xynole and Core Mat to play with.

As I understand it, Greg buys the base epoxy from the big distributors and creates the final product at their factory in Tucson. It is a more modern resin/hardener than WEST uses. Stronger and way less volatile. I got lost in his explanation of just what all goes on, but the newer resin / hardener has better benzine rings or something. It made sense when he explained it but I am flunking the essay test here.
Larry, John sweet in Maryland www.sweetcomposites.com carries dynel fabric, sleeve, and cord. His prices are very good and he offers good pricing on Kevlar and glass also. He also offers polyester fabric which I plan to use, not sure how this compares to the xynole fabric and wether its the same stuff. My glass kayaks are solid laminate 6 layer deck, 7 layer hull of alternating layers of glass/poly. The poly was described to me as a poor mans Kevlar in that it offers good stiffness and is resilient to impact. All I know is I have hammered those bOats on rocks over the years, and it's rare to get impacts ever get thru. The alternating glass poly is a good laminate, and would be a good bottom for wood boats I think

Actually John Sweet retired a few years ago and sold his business to Davey Hearn.  I used to race with both of them back in the day.  They are both knowledgable long time whitewater boaters and boat builders.  I think that the transition in ownership was pretty seamless to the customers.  I like dealing with Sweet Composites.

Thanks Brad for the information and the connection to the web site for this product. I am restoring a drift boat that spent too much time exposed to the sun and elements and I am getting close to a point in this process where I will need to repair some plywood that has cracked on the surface and partially delaminated in small areas. I had planned on using System Three Clear Coat after sanding down the bad spots, but I wonder if this product would not do a better job. I think I will give them a call and get their take on it. I wonder if the 2040 resin can be used as as  a soaking type  of application or whether I should use it with glass or a filler product? Thanks again for the information; it could not have come at a better time. Roger Rippy    Bozeman, Montana

What you want for saturating that sad, tired plywood is one of the mythical "penetrating epoxies," which are super low viscosity. The leading brands seem to be GitRot and CPES ( clear Penetrating Epoxy Sealer)(also marketed as Restor-it). There is also one made by Progressive Epoxy called ESP 155. These products are pretty thin--CPES is like water--and they soak in pretty deep and harden.
However, Greg at Resin Research says some of the base epoxies those guys use may be low quality, and most of the product us thinner, usually xylene. And they charge you huge dough for what is mostly $15 a gallon xylene.
He recommends using his other line of low-viscosity epoxy, which they make for infusion work, like vacuum bagging. I have a bottle of the thinnest of those, Composite Pro 2090, which is the one he recommends. He also says if you want it even thinner, you can thin it out with 10% xylene, or possibly push it to 20 % xylene. I have not yet had a chance to experiment with this, but imagine it will be pretty good.
Before I met Greg, I had already purchased 2 gallons of CPES, most of which I soaked into my current project last night. We'll see how it goes. The story of that is on my blog, fretwaterlines.blogspot.com. You can check that to see what my results are.
Best of luck--

Thanks Brad for the feedback on this. I will give the Composite Pro 2090 a try for this repair and I think that I might sand down the interior deck and lay down a single layer of glass. With the pricing on this and the smallest amount being nearly a gallon total, I should have plenty left over from the bad plywood spots for glassing in a new floor. I think I will be waiting until it warms up some before I tackle the epoxy parts of this project; I keep the garage at about 40 to 50 degrees which may be too cool for a good setup.  Thanks again Brad for your help. Roger

A space heater under the boat does wonders. My shop is wood heated and the outdoor temps are approaching zero at night.

Today's analysis of Restor-it vs: xylene-thinned 2090.

The former does soaks in deeper, although the off-gassing is incredibly, unendingly toxic.

The later soaks in well (though not as much as the former), don't make no stink, and is sure easy to work with.

Timely - thanks Brad.  I need some epoxy for the Portola and I'll give it a shot.  It's coming along pretty nicely - I'm pleased (sometimes).  Measurements are all coming out like they should and it looks like the pics from 1962 - should be doing the paint job right after Christmas.  How's the Thumb coming along??


Well, I like the product enough that I just ordered a Sticky Stuff dispenser for it ($300). So did my pal Dan. So we're pretty sold on it, and it's not just that Greg Loehr is a nice guy. If you work in small amounts, like I do--a bit here and a bit there, it is really hard to measure accurately, and the dispenser is the way to go. Greg works in big batches, so he can get away with eyeballing it in graduated cups.

Anyhow, give it a shot and I'd be tickled to know what you think of it. Make up some test pieces and whack 'em. Very impressive, especially when compared to identical layups of more traditional epoxies.

I am very happy to hear the Portola is coming along. If you weren't making one I would have, since it is the 50th anniversary next year. But no sense making two of them. Although it is an interesting boat and a seminal one, as soon as the Briggs came about, the Steele boats got left in the dust. But I sure would like to row it!

The Boop is rocking along at full speed. We just painted the hull tonight. It is one sexy boat and we are hoping to do a trip in her this winter before I find her a new owner. Hayes said she "turned like an aerobatic Pitts Special.” I've been posting the progress on


I have this vague thought that maybe the Steele haul was great up until a certain size, after which Briggs's Rogue hull excelled. Hard to say. Them little McKenzies sure are fun, but the big ones never got much traction in Grand Canyon.


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