Rights, wrongs and weights. What a surfboard weights post 2.

This past week I got into a discussion about board weights with one of our lam. shop customers. It all started when the customer was saying the fresh batch of shaped blanks he’d just brought in were to be laminated in epoxy.

The boards were shaped polyurethane blanks, usually laminated with polyester resin. So I asked why he wanted them laminated that way. His response “ because they would be lighter.” I asked “ how much lighter…. Compared to what?” He didn’t have an answer… well actually I think he said something like “you could tell by lifting them”. Maybe, Maybe not. But in reality if you don’t actually weight a board you really can’t know for sure if one surfboard is lighter than another.

So we started talking about the variables that may make one board weight more than another which lead us to two of the four blanks he’d brought in. He said, “ check this one blank”… as he picked it up… “it’s lighter than this other one.” I suggested we weight them, which we did. Sure enough one weighted 5 ounces more than the other. Funny thing, the one that was 5 ounces more was shorter. The lighter one was a 5’ 11” the other was 5’9”. Both made from the same foam and both had the same wood stringers.

So “see, I can tell by feeling what weights more”. He says. Ok good, but why would the shorter board weight more than the longer one? Reason? Foam volume. The shorter board was wider and thicker. The boards were machined so it was possible via the computer file to access the volume measurements of both blanks. Sure enough, the over all volume of the 5’9” was more than the 5’11”. With a little math we proved that the blanks were almost exactly the same weight per liter of foam. But, even though the one that weighted more was shorter it had more foam over all, as well has a wee bit more wood over all so that’s why it weighted more. I think it would be safe to say the over all girth of each board is different as well so the skin that is applied over the foam will add a corresponding weight increase. The finished weight of the 5’9 could end up being 10 or 12 ounces more than the 5’11”.

So what’s the point?

There is no mystery why one board weights more than another, there are reasons. If you want to know why one board weights more than another in your quiver you can find out. If you’d like your boards to have a certain weight pick the shape, core, shin and finish that would have the weight outcome you are interested in. And in the end, you need to weight the board to know the real weight of your board.

D.R.

The core and over all shape is where the weight thing starts.