What durable yet flexible material should I be using for my longboard?

June 17, 2006 9:14 AM

I'm going to make the deck on my next longboard my self. What durable yet flexible material should I be using?

The distance between the wheels of this board will be about 90cm (~35 inches), and the deck must be able to carry me on top of it, standing between the wheels, without it breaking. This is essential, I'll be riding fast on asphalt, so if it suddenly breaks in two I'll be in trouble.

Flex is also key. Feeling the board bend slightly as you ride through a turn is part of what makes longboarding great. Achieving this without compromising durabilty is the hard part.

The last time I did this I used 10 mm (~3/8 inch) of birch plywood. That deck had a shorter distance between the wheels and lasted for 2 and half season. It was good, but not perfect in terms of durability.

It seems reinforcing the wood with fiberglass would be a good idea, like having two 4 mm birch plates with fiberglass in between. But first of, I wouldn't know how to make them stick together, and second, I don't know what tools I'd need to cut it into shape.

How would you do it?

posted by cheerleaders_to_your_funeral to Sports, Hobbies, & Recreation (3 answers total)

You don't actually want fiberglass between the ply layers; you get maximum strength from fiberglass by putting it on the outside of any structure it's supposed to be reinforcing, to create a stressed skin. For a skateboard, where your weight between the trucks wants to compress the top of the deck and stretch the bottom, you want your fiberglass on the bottom.

Use the same plywood as before, and add a layer of woven glass mat to the bottom. Let the resin set up properly, prop the board up on a couple of blocks spaced where the trucks will go, and see how it feels. If it's still too flexy, add a second layer of glass mat and more resin. Allow yourself a few test-to-destruction roughs before you start your final deck.

Something else you could maybe do: paint the top of the deck with a fairly thick layer of resin, then throw on a shovelful of dry coarse river sand while the resin is still liquid. Brush off the excess sand when the resin has set up, and put another coat over the top. This would give you a grippy, wear-resistant finish.
posted by flabdablet at 10:53 AM on June 17, 2006

From your question I get the impression you don't understand exactly how fiberglass is used. It is a fabric, woven from strands of glass. You lay the fabric out and then fill the weave with epoxy. So it sticks together all by itself, because epoxy is a glue. Usually you'd use the wood inside sandwiched between two layers of fiberglass for the reasons mentioned by flabdablet. This is how I'd do it:

Cut quarter inch birch plywood to shape desired.
Use finnish birch if you can get it, it's marine grade and of better quality. Otherwise baltic will do. Check out your local specialty plywood dealer. Lightly sand with 120grit. Put one layer of 6 oz plainweave (Eglass) on each side. Mat is heavy and has poor flexibility. Wet out with epoxy (you should be able to find West Systems or MAS locally). Use oral syringes to measure, you won't be mixing enough to justify pumps for pumps. Wear latex gloves. Clean up your skin with vinegar and your tools with acetone.

I'd do 3 fill coats cut with graphite powder on the bottom for abrasion resistance. On the edge build up some some graphite goop. Either paint the top or give it several coats of UV protecting spar varnish, Z-Spar and Epiphanes are both good examples of this. Epoxy doesn't like UV, it turnes yellow and brittle.

For suppliers, I'm sure you can find something locally. Don't use automotive fiberglass, it's coated for compatability with polyester resins. Otherwise Raka, Sweet Composites, Noah's Marine or maybe one of the model aircraft places could set you up.

As for fiberglassing technique, I'm not going to get into that here. I know I've seen skateboard building websites out there, but for a basic primer the boatbuilders will do: Here and Here. You could probably google up some good info from model aircraft builders that would be more compatable with your application, but those two links should give you an idea of what your after.
posted by vonliebig at 11:06 AM on June 17, 2006

Thanks, those are great answers. I obviously didn't know what I was talking about when I posted this, but you were still able to give me the answers I was looking for.

I guess when I got the idea of using fiberglass I was really thinking of a product like plexiglass. Anyway, thanks for the input, it was certainly helpful.
posted by cheerleaders_to_your_funeral at 7:01 AM on June 18, 2006