Been working on a virtually waterproof structural blank that could be used without glass (or at most 1 layer of glass all over) with just an epoxy finish coat, Can be hand shaped and machine shaped. Alcohol based no gassing and white in colour.
The issue is that a 6’7 blank is coming out just under 4kg… working on ways to get the weight down…
But whats the thoughts of a blank that floats in between PU and EPS but is heavy? Is it an option that you would use knowing that its virtually waterproof and very difficult to ding?
Cost of producing is slightly less than Varial, We are at the stage to throw serious money at it… but worried that it will be rejected because of the weight!
The Swaylocks crews thoughts? Or is it just one for me to play around with my own boards on and forget about spending the money!
Sounds interesting but also a tough row to hoe with the focus on weight these days. The younger crowd wants them as light as possible to the point of sacrificing durability. Go figure.
Yeah maybe multi density blank as mentioned but extra cost may be a deterrent , You mentioned the density , the last foam similar to this i used was XPS which was a great durable foam that only needed one layer of 6 oz cloth and made a very light board but it had delamination issues because the resin couldnt penetrate enough to get a strong bond. Could this be an issue with a very hard foam core?..
Thanks for the feedback, been playing with each day and starting to get consistant results, so I’ll try to answer what I know so far!
Charlie - density started around 100kgm3 have dropped it down so far with different additives in the mix by 20-30% but aiming to drop it by 50%, was speaking to a chem engineer today and he said that one of my main additives in the mix was at 300kgm3! He gave me a few alternatives that might reduce the weight… ordering tomorrow
Molding into a blank form so less waste and easier for machines and shapers
Noe - Some of my best boards were XPS also! Loved the feel and the flex I got out of it, but delammed also. Can’t use Polly because of the mix of additives but epoxy sticks to it!! I couldn’t rip off the glass which we lam’ed on no matter how we tried! Could change when we try out other additives to make it lighter.
SRFOCO - Yep that is another track we are going to try, ordered SL EPS sheets a couple of days ago, but this is my last option. worried to be compared to the “S Core” and also if a shaper cuts the blank wrong its not waterproof anymore. Though Dan Mann seems to have got around that with “Incide” supplying files on how to cut on the shaping machines… So it is an option!
I’ll keep you posted as I go along, if not light enough… I can always make molds for bricks and build a house out of foam! lol
Weight will always be a big issue. People want light boards. Looks are important too. If this foam is so strong, I’m guessing the board would have to be 100% molded to finish shape or machine shaped. Doesn’t sound like something you can take a green planer to.
There are some very strong and light foams out there. I broke a high end tennis racquet years ago and was surprised to find that the frame was a molded poliurethane and graphite foam of some sort.
yep agree Mako - weight is the issue, met up with a company this week that have an option on swapping one of the main component that was heavy for a alternative of 1/4 of the weight! hopefully this will bring the weight down enough? Its hard but cuts and sands like Balsa so using a planer is fine. (but wont know until we try this new additive).
No probs skatement, when we get closer to the finished product we will probably have a few 2nds around so might be good to get someone on here to build one… i’ll keep you in mind
Heres a pic of the foam close up, this section was just cut off with a hand saw, same density all the way through, been told this might change a little with new additive
You can’t forget if it cost significantly more than a standard poly blank and the performance is not as good you’re going to have a tuff sell. Price is a deciding fact for many surfers
Thanks Pierpointscott, yep cost is another issue… cost of materials of a pu foam is very cheap! Mark up is huge!! We cant compete on price (unless I set up in china which I wont do), though we are looking to reduce the mark up and also set up of molds costs we have worked out a way to do it cheaper and not have the massive concrete molds around taking up space. So to answer yes more expensive but cheaper than other newer versions of foam which has come on the market…
The other point im more interested in - the performance of pu? in shaping? in end user? If I can make a foam that has the some good things of PU, Eps in a foam that is almost waterproof, hard to ding, the same density right through the blanks so no issues if you shape too deep and rides well? Isnt that performance in a few different areas?
There is always talk on here about the core being the weakpoint of the board? What happens if we fix this? Doesnt that mean for a shaper less cost on extra fiberglass? Time taken to do extra steps so less labour spent on the build? less water affected, so less to fix a ding? Wouldn’t these be factors also?
This is awesome so far as its giving me an insight into what we need to do and what hurdles that we will have to jump over! Thanks guys
You speack of a structural sandwich core. Composite industrie work on it for long time, nautic and more aero don’t really care about price but nothing “structural” at less than 100kg/m3. So if you find it you will don’t care of surfboards building anymore LOL.
One of the first things I thought of when you said weight was an issude was building a internal frame like a hollow wood board skin the frame with your new foam and use the new foam for the rails. My other thought for testing would be to build a full on gun some surfers prefer some weight in large wind chopped surf a little weight with a nice shock absorbing flex would sure help smooth out a ride in nasty conditions. Just something to think about.
One of the first things I thought of when you said weight was an issude was building a internal frame like a hollow wood board skin the frame with your new foam and use the new foam for the rails. My other thought for testing would be to build a full on gun some surfers prefer some weight in large wind chopped surf a little weight with a nice shock absorbing flex would sure help smooth out a ride in nasty conditions. Just something to think about.
Thanks lemat caught up with a company that does floating piers and showed the foam they were impressed with what we have done so far… So if we can’t get it lighter be able to do that with the foam!
Artz thanks for that I have the heavy blank that I thought I might just shape up anyway and ride it, might make it a step up and see how it goes and give it to one of the local big wave legends
