adventures in dysthymia

Friday, September 14, 2012

Of Pop-outs and Other Surfboards

In that I mentioned ordering a stock more-or-less mass-produced surfboard, I thought I’d make some comments on the whole manufacturing thing as it is today. And as it was yesterday, as well – the pop-out versus the custom board.

The original ‘pop-outs’ were just that – they popped them out of a mold. This was something that started in the ‘60s, as far as I know. A mold would be lined with resin-saturated fiberglass mat (not cloth) and then injected with polyurethane (PU) foam. The result was a board that was both heavier and weaker than a standard shaped design, but cheaper.

Only a bit cheaper, though, and there is an economy of scale involved here. Molds are relatively expensive and one must sell a lot of identical boards to make them worthwhile. There are still cheap molded boards today, but the process has changed. Now it’s inexpensive polyethylene skins, as found in ‘soft’ boards or the lines from companies such as Bic.

There are more expensive molded boards too, such as those from Surf-Tech. It is a different process but still ‘popped-out.’ That does not prevent them from being decent surfboards.

Surfboards from the late ‘50s (when wood was largely abandoned) until fairly recently were generally hand-shaped from polyurethane foam blanks that were somewhat close in shape to a finished board. The less foam the shaper had to remove, the stronger the board, as molded PU is strongest and densest in its outermost layer. Indeed, some boards were pretty close to being pop-outs in that they underwent little more than a bit of final sanding before the fiberglass was applied.

That is where the real difference lies between a standard hand-made surfboard and a pop-out – the lamination of fiberglass and polyester resin for a strong outer shell rather than a one-step molding of both interior and exterior.

The ever-growing use of polystyrene foam has changed things some. PS has one great advantage over PU, namely that it is the same density and strength throughout. One could start with a block of foam and cut away as much as one desired without compromising strength. This, in turn, opened the way for working with CNC machines that roughly shape the board without needing such a large selection of almost-the-right-shape blanks.

This is much more cost-effective for modest runs of standard shapes than using a mold. Want to make a small change? Just get on your computer and reprogram the CNC. No need to invest in a separate mold for each board design and length.

Using PS foam does mean one must switch to epoxy resin. That’s no big deal now but was a pain when builders began experimenting with it. I built a polystyrene boards in the '70s myself. It was a terrible pain to shape the sort of PS that was available then – the best approach was to cut it with a hot-wire tool. Now, the available PS surfboard blanks word fine with the traditional shapers’ tools of plane and rasp.

The stock board I just ordered (from Isle Surfboards) was done in this manner – CNC shaping with hand-finishing and then hand lamination with fiberglass and epoxy resin. And, yes, it was made overseas as are many boards these days, whether in China or Taiwan or Brazil or wherever. Shoot, a board I had twenty years ago was manufactured in Taiwan (though by a supposedly Australian company).

I have nothing against this sort of machine shaping. If it’s good enough for Taylor Guitars, it’s good enough for my surfboard. Not that my plans for the future wouldn’t include a true custom board (or guitar, for that matter!) but right now, a decent stock design will be fine.

As long as it’s not a pop-out, of course.

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