lemat wrote: Only full cure epoxy should be sand.
Of course, but there are exceptions, like laps, and touchup of sand throughs.
Lemat, Dwight, I'm a big fan of both of you and I know it is hard not to jump in on these questions but if this is going to succeed, we need to let the guest answer the questions. Thanks for your understanding.
Personally I'm always ready to learn, although I do not always like being taught. - Winston Churchill
One of my fondest memories is Greg pulling up to our factory in Atlantic Beach Fla.He would be driving this huge Dodge Power Wagon with 40 blanks crammed in it.He looked like a wildman.This was around 72' or so.
Most of you know him as the epoxy guy but he was power shaping really sweet PU boards when Natural Art was king of the world.
If you were glassing a dozen short boards a year for yourself and friends, I'm wondering what fibres you think would be the best at the current time?
Foam most often used being USblanks PU foam with a stringer (red or blue), which is what is available where we get them cut.
Kwik Kick resin.
Currently using a mixture of S glass and E glass, but keep looking and reading about all the alternatives.
Thinkin' Mr. Loehr is in transit so don't load him up too much, HA
I would rather be someone's shot of whiskey, than everyone's cup of tea.
Hi Surfteach. I'm a bit out of the loop on bead stock. Nova made the best about 10 years ago which still may be the case but don't ask me what product number, it's been a long time. As for block I use White Hot from ProWall which is right up the road here in AZ. I've heard that the place in Kingman also makes good stuff. The foam in CA has urban blowing agent emission restrictions on it so it's not that good for boards. FL we use Imperial or Carpenter.
Hi G Daddy, sounds like your moving ahead with the bagging nicely. I do like Innegra between layers of fabric which has always seemed ideal. As for higher modulus patches that's something that one of my board building mentors, Ted James of Fox Surfboards, used to swear by. I saw the results and I have to agree with what I saw. Couple of things about high modulus though, using it throughout the board can cause the laminate to be brittle which can cause failures. I've seen this in some of our earlier formulations. Also the modulus should follow the choice of fabric, high modulus fabric goes with high modulus resin, medium modulus fabric goes with a more medium modulus fabric and so on. And your suggestion of bi axial can be used to advantage as well. One other aspect is resin ratio, lower resin ration allows you to use a higher modulus resin because with more fabric content you are effectively lowering elongation.
A few out here are trying for optimum performance in crappie surf. So at the moment and I speak for myself only. Combinations of rocker, shape and the current “flat tucked edge” bottom is where we are at. So Cal.
Considering your FLA experience I humbly ask your take on bottoms that work in lesser conditions.
For the last year and a half we have produced high bio content resins, about 40%. When we looked at existing bio content resins most contained a percentage of epoxidized oils, tall oil mostly. These resins are characterized with low physical strength and quite low Tg. My opinion is that making a lower strength product in order to be "green" in not really "green." So we were on the hunt for a better way which we found by using a glycerine based, bio deisel derivative, ECH in our chemistry. Using this method left us with exactly the same physicals as we've always had. Unfortunately after almost two years of production a very large European paint concern, Anzo Nobel, bought our suppliers entire production and we were phased out. So we went on the hunt for a new supplier and at this time we haven't found one for our North American production. Our China facility is up and running with a replacement which gives us about 50% coverage. At this point well just continue to search until something comes online, it will and well once again be able to produce bio resins the right way.
Hi Barry, The new Ultra additive is an optical brightener that we can include in any of our resins. It is quite a bit brighter than anything we've made previously which seems to be a trend that some builders are following. It certainly makes brighter boards that any other brightening method. It also holds up very well lasting at least 300 hours in direct sunlight. This was a lot of work for something entirely cosmetic which suddenly seemd to have fallen on the shoulders of material suppliers. Oh well. As for post cure, the can have incredible result but unfortunately we are limited there by what our foam will take. But here's a cool way of figuring post cure. Room temp epoxies cure in one week at 77F. Every 10F added cuts cure by 1/2. So 87 is 3.5 days, 97 1.75 days, 107 20 hours, 117 is 12 hours 127 is 5 hours, 137 is 2.5 hours and 147 is 1.25 hours. You can stop there because the foam won't take any more. When you get above the 127 level your going to begin to see a much different animal than RT cure. Cross link density improves significantly so that your modulus and elongation both go up. To do this takes some equipment and some tests to get it exactly dialed in. To get an idea of what this is like wrap a piece of wet cloth around a soda can and heat at 150 for an hour or so. Then do one at room temp for a week. Demold each and compare.