As part of an assignment, Im looking at alternate methods of manufacturing than the existing hand lay-up. I read the below on a website on molded surfboards:
Molded Surfboards (Pop outs): Molded surfboards construction process is the following: a female mold of a surfboard in two halves, top and bottom, is fiber glassed.The two halves are then brought together and liquid polyurethane foam is allowed to expand to fill the void in the center. The join line is later cleaned up and finished with a strip of special tape.The downside of molded surfboards is weight – they are heavier than a custom board.
The above information is quite incomplete and I wasnt able to find much on molded surfboards online so I have some questions for those that are familiar with this production technique:
The fiber glass being used, is it prepreg or wet layup?
After the layup, is the mould vaccum bagged and cured in an oven or an autoclave?
im not sure what they r referring to when they say “special tape” is used to join the two halves? what is special tape?
Also if only the edges of the skins are joined using tape, does that effectively mean that the foam core is completely delaminated from the core? wouldnd that greatly effect the feel and performance of the surfboard?
My suggestion would be to use the prepreg method, a female glass fiber mould can be used, prepreg laid up on it and then vacum bagged and auto claved to ensure low void, high volume fraction. when both skins are done, eps foam will be used as the core and both the skins will be bonded. what are some techniques that can be used to bonf the two halves? I understand using tape is not the most efficient way,…
Please note this is just for a manufacturing assignment so some things might not make too much sense cost wise, if they did people would already be doing it.
I’ve heard stories of Velzy having IRS issues back in the day but that’s as far as I’ve gotten into it. Could you explain either what his issues were and/or what this board had to do with said issues?
Simply; He owed so they shut him down ‘til he settled. A couple of differant people used his name for awhile and got away with it. He had a deal with a guy for some boards (I think it was Nomad) and the guy burned him. He was involved at Jacobs for awhile, but couldn’t have his name on anything. All of this in no particular order. The Nomad thing he told me himself. He ghosted for a few people as well.
A smart fellow by the name of Kendall Nishimine, Vice President of Hydro Epic, used to post around here pretty often. Unfortunately the brand folded for some reason… at least the old URL to their website seems to be down.
cool video monkstar - i love that they are doing all this high tech composites work with carbon, molds, etc but then put the 2 halves together with spring clamps and masking tape lol!
thats a cool thread stoneburner i had not seen that one! i love the idea of the internal bladder i think you could possibly make that work with a clamshell mold to get a ‘one piece’ hollow molded board…
3 - in this case tape is just a term to desribe a narrow roll of woven fibers (probably fiberglass). it would be applied with resin and then sanded flush.
4- when the liquid turns to foam it will adhere to the fiber skins. think about gorilla glue - it is a type of polyurethane foam.
your suggestion is pretty high tech - prepreg is expensive as are autoclaves and very expensive to maintain and run. the ‘pop-outs’ made in the fashion you describe were made as cheaply as possible, not for performance. check out surftech ‘tuflite’ i think it is called - they are a molded ‘pop-out’ geared more for performance - you should be able to find some info on their construction methods. also libtech is making molded boards aimed at high performance but they are very tight lipped about their process - from the materials in their boards, it looks like they are doing infusion. as far as bonding the 2 halves…i dunno…there are probably some innovative ways of doing it…
