Nice boards are shown on your site. I was not able to discern the deck contours of those but an old Swaylocks guy, Benny1, and I came to the same conclusion regarding flex and deck structure… that the shape was as important as the build method when it came to how it flexed. We both agreed that a scooped out tail deck would still allow flex pretty much regardless of the construction. Bert’s boards were often shown with deep concaves as well.
A sample I received from a composite supplier was nothing more than t-shirt material soaked in a urethane resin and wrapped around an inflated balloon. It beautifully illustrated exactly what I’m talking about. It flexed quite easily with the shell facing outward - I.E. the ‘tension side’ being convex. Trying to flex against the ‘dome’ (‘tension side’ being concave) was nearly impossible.
I believe the same effect takes place with the deck of a surfboard. After stripping the fiberglass off an old beater, I discovered that even plain old fiberglass/polyester is very resistent to flex against the convex structure when the shell came off a dome decked board.
Looked back at the original post and question about contour mats.
My brother made a nice double concave contour mat and we used that quite a few times. One problem with the mat was when he made it the heat from the curing resin messed up the board he used as the donor shape. We used UV cure Poly resin and the mat was about 1/8" thick, maybe a little thicker.
An alternative he came up with was to use other boards we have as rocker beds and they would transfer any contours the board’s bottom had to the one we were making. It works great if you want to copy a board’s rocker and bottom contours. We also have an 8’ long rocker bed that fits inside of the vacuum bag.
Just look up the posts from Oneula around 2005 and 2006. Unfortunately he started getting allergic reactions and stopped messing with epoxy resin. I ended up doing all the resin work and he did some of the finishing. Then he pretty much stopped doing boards, and I just did regular glassing over various foam cores until he gave me a vacuum bagging setup.
Nowadays he’s allergic to a lot of stuff, and I don’t know if all the work we did with epoxy and other resins triggered it. I can get epoxy on my skin and not have problems at all, but we’ve always had different allergies.
For anyone thinking about working with epoxy, you need to be careful about becoming sensitized. Josh Dowling AKA Speedneedle was making incredible compsand boards, but he became sensitized too.
Best advice we can give. You would never have epoxy on skin unless it is fully cure. Work with full body protection for glassing and even more for sanding. Cure in oven before sanding. Not so much people have long time carrer in epoxy industrie. New epoxy développement in surfboard industrie will product some drama when you see how it’s used by many, even if epoxy became a less sensitizer product.
Becarrefull of pentane from eps, even more isocyanate of pu and styrène of polyester resin. All cancerigene products.
You’re starting to get me concerned about working with epoxy. I’m just a backyarder but I’m constantly sanding/glassing/etc. I always wear masks/respirator as well as goggles and painters coverall suit. None of it really itches me when I’m working with it but my hands are constantly exposed to dust (not uncured resin). I wear gloves during glassing, but not sanding. Should I be wearing gloves to sand?
The dust doesnt itch you!? I always wear gloves and full covering for non wet sanding, because it sticks to the pores and itches, a lot at least for me
Doing pretty much the same, except not wearing a respirator for laminating.
I wear a vapor respirator or dust mask, gloves, shorts and slippers when I work with epoxy resin. It gets on my skin and I wash it off with Denatured Alcohol, or sometimes white vinegar.
If I use poly resin, which is rare, I use a good vapor respirator. Polyurethane resin has worse vapors to deal with. I usually only use poly to make fin panels, but I have done a handful of PU/PE boards in the last decade. I use acetone with poly resin.
I wear a dust mask when I sand, no gloves, shorts and slippers. Sometimes I wear a long sleve shirt and long pants. I do have a vacuum attachment on my sanders, but I still get a lot of dust. Resin dust doesn’t itch, it’s the fiberglass. I use a soft bristle brush with soap in the shower to get the fibers off my skin, then follow up with a normal shower with a wash cloth.
I figure that the sanding dust will get to me one day, and I’ll have to deal with COPD.
I hope not too far off topic: Be careful when handling fiberglass. In a stream of light you can see particles of glass floating in the breeze just when handling the stuff. Cutting releases even more. Inhaling that stuff can’t be good for the lungs…
After 25 years of exposure building boats in epoxy and now building boards in epoxy only, I’m more than a little amazed I am not epoxy intolerant. Speedneedle really got hit out of the blue, done. Anyway, it takes epoxy to build in composite so for as long as I can I will. Would hate to go back to poly.
What happened to Josh was tragic. He was so far ahead of most people with his compsand boards. As John mentioned the fiberglass particles are an underated health problem.
My brother switched to a forced air respirator and a full coverall suit, but he still avoids using epoxy.
IIRC Huie got so sensitized he would break out in a painful rash just from walking in a room with an open bottle of epoxy. My research told me to also be careful handling or sanding epoxy that is hardened to the touch but not fully cured.
For French working health regulator sanding is the most dangerous composit work where people get sensitize to epoxy because of inapropriate protection. For me it’s strong ventilation, vaccum Sander, full body suits, gloves and pressure ventilate respirator. Cosmonote wear that make my mate laugh, but in fact only safe way to sand.
