I'm having a board made and it's standard foam with an epoxy finish. Ive ridden straight out epoxy boards and dont really care for the stiffness. I was told to try the PU/epoxy since it's more durable but still has decent flex. If you make and or have ridden this type of board I'd like to get your input on ride and durability.
epoxy actually has better flex patterns than poly, i have done a few pu/epoxy boards but mostly do pu/pe. Epoxy is stronger, and you really cant feel the difference to much in my opinion. i really dont like epx at all just preference, but pu/epoxy feels good to me. just my .02
I have done 2 boards that way and it feels just like polyester resin to me. Most of the difference in feel comes from the foam not the resin from what I can tell.
I've made maybe 10 PU/epoxy boards. Some of them I rode for years and loved. They seem very durable due to the strength of the epoxy resin and have held up well. I also thought the first few EPS/epoxy boards I rode felt stiff so I hear you on that. I have since ridden a few EPS/epoxy boards with more pinched out rails and lighter glassing that did not feel so stiff. Still, PU/PE is my favorite board construction.
If you compare just the core material... standard PU and 2 lb pressure molded eps... the flex is nearly identical, but the eps will be lighter. Add the same stringers, and nothing changes. Ride both cores for 2 years, and one will feel more "dead" than the other, which will still feel like it has "life," and the dead one will be the PU core. Shear tears at the stiff cell structure of PU, breaking down it's integrity, while eps beads deform under shear, but don't break. Bottom line... eps cores have a longer life. Compare just the resin... quality surfboard epoxy vs. polyester. Epoxy has a higher tensile strength (resists being torn apart), higher flexural strength (bends without breaking), and higher barcol hardness (ding resistance), and slightly higher flexural modulus ("stiffer"... takes more force to bend, but also springs back faster). These are broad generalizations, but useful to generally compare resins. Keep in mind that this is the resin itself, not reinforced with any laminate. Glass... typical 4oz build all around. Put them together and you get a epoxy/eps board that is much lighter, slightly stronger and stiffer, but with better "spring back," that will keep it's lively feeling longer than the same pu/pe board. It will also resist delamination better. But if what you're after is strength, in terms of snap resistance and ding resistance, you'll use the savings in weight to make up for a heavier glass job... as much as 6oz all around... for an equal weight board that is much, much stronger, but also much stiffer - the added glass creates stiffness. To get more flex out of this board, you need to go stringerless, or go thinner. An 1/8 thinner will get much of the flex back that you're used to feeling in a typical pu/pe board. But that volume loss changes how the board floats and paddles. A PU/epoxy build will be very slightly lighter, slightly more ding resistant, slightly stiffer but springy-er, but will slowly "die" in how it feels over time due to the PU core. It will also delaminate from heel dents like a typical PU/PE.
Yea Ive always been a PU/PE rider and am just looking for some strength options without making the boards to heavy. I ride my boards pretty hard and just want a little more life without going EPS/Epoxy on a short stick(short to me is 6'2 to 6'6 with my large frame, 210lbs and pushing 50yrs). They just ride to high on the water to suit me when paddling as well as being to stiff for my taste when riding. I might would consider one in an LB......... I appreciate the comments from all and will continue on with the PU/Epoxy build. LBC.......Very informative thanks.......Ive never had an issue with delam on a poly except for once in an area where the paint was a heavy, dark color. A2tall..... your two cents is worth $10 in my book
the flex is definitely a little different with the epoxy resin. goes good though, i won the belmar contest on a pu/epoxy board. i think they feel a little stiffer, and buckle easier, but are stronger as far as rail dings and little stuff goes. i think epoxy resin is probably a little lighter and a good alternative. i hate eps blanks though, just feel weird. brian wynn has been mixin up resin and blank combos for awhile. i know hes made me 8 or 10 boards with a regular blank and epoxy resin and they have been great!
I thought Brian didn't really use epoxy at all, i know he is a big fan of Resin X and always uses poly. maybe that is old news