This Instructable is a step by step description of the process of building a skateboard deck, which includes: making a bending mold, building a bag press, and squishing /cutting plywood into the shape of a skateboard. These instructions are for a specific board but are intended to be easily modified to make any type of skate board, long board, or bent plywood project for that matter.
Being a skateboarder and a constructive individual I always fantasized about making my own custom designed and constructed skateboard, made to fit me and if I wanted to I could easily make multiples. Now I can, and you can too, just follow these steps:
I suggest reading all of the instructions before starting the project!
Step 1: Materials
1 4x8 foot sheet 3 /4inch Spruce plywood
2 5x5 foot sheets of maple veneer
Hand-held Jig saw
1 liter of wood glue
8 12inch wood clamps
20 gauge thick vinyl sheet (or water bed bladder)
2 part 5 minute epoxy
Vacuum cleaner with hose attachment
3 / 4inch plastic conduit pipe
Dowel that fits in conduit pipe
Plastic Mesh from dishwashing scrubber (the one that looks like a mesh donut)
Skateboard trucks, wheels, and nuts and bolts
Optional (but helpful)
Hand-held belt sander
Step 2: Building the Mold
The mold is what the plywood is squashed against forcing it to take the curvy shape of the skateboard. It will be made from stacked cross sections of spruce plywood. First create a cardboard template of the mold cross sections(fig.2a) and use it to trace out 15 versions on to the spruce plywood sheets.(fig.2b) Cut out the cross-section layers then glue the layers together and squeeze with clamps,(fig.2c) wipe off the excess glue that squeezes out.
Once dry, remove clamps and use rasp or belt sander to remove any differences in the cross sections so the surface of the mold is smooth.
Mark off area for inner concave where material needs to be removed.(fig.2d)Make a template of the desired inner curve(fig.2e) so you know exactly what material needs to be removed with the rasp or belt sander.(fig.2f) Refine surface of the mold first with the coarse and then with the smooth sandpaper.
Step 3: Making a Bag Press.
A bag press is basically a giant ziploc bag with a connector where you can attach a vacuum. A bag press works on the principle that nature resists a vacuum therefore if you suck all the air of a container it will squeeze in on itself therefore creating a press that is excellent for bending things onto a mold.
Take two 3 foot x 4 1/2 foot sheets of vinyl plastic (fig.3a)and apply a liberal coat of contact cement glue on both sheets along the two long edges and one of the short ends.(fig.3b) Allow the glue to dry for 45 minutes. Carefully, start with the back edge and press glued edges together being careful not to create ripples. Once the back edge is pressed, work up the sides to the open end of the bag. Once all surfaces are contacted apply force to tops of glued areas by rubbing with a spoon or a rolling pin. You can then add extra reinforcement by folding strips of duct tape over the edges to strengthen the seal and plug any leaks.(fig.3c)
Now, you need something that will suck the air out of the bag. I used a vacuum cleaner with a hose attachment which worked fairly well. You also need to figure out some way of attaching the vacuum to the bag. I used a plastic tube that hooked up with the hose attachment.
Create a hole smaller than your connector pipe (but large enough that it can be forced through) in the middle of the top layer of the vinyl sheet.(fig.3d) Then force the pipe through from the inside of the bag out so that it is almost all the way though.(fig.3e) Mix up half a table spoon of 5-minute epoxy and place liberal amounts of the glue in the trench between the plastic pipe and the vinyl from inside the bag.(fig.3f)
Now you need to create a giant zipper to seal the bag. To do this take a plastic 3/4 inch conduit pipe(fig.3g) and a dowel that fits not quite snuggly inside it. Cut the pipe and dowel so they are a little longer than the opening of the bag. Then cut a strip out of the conduit length wise(fig.3h) so the cross section of the pipe is a "C" shape.(fig.3i) The cut can be made with a sharp exacto knife or I used a mini circular blade in my Foredom. To make sure the cuts are straight it helps to first use a marker to draw guide lines of where you want to cut. How the seal (zipper) works is that the "C" shaped tube goes on one side of the opening of the bag and the dowel goes on the other side. Then the sandwich is squeezed together by hitting the dowel with the rubber mallet, forcing the dowel and vinyl inside the c-tube creating an air tight seal.(fig.3j) More or less material may need to be removed from the "C" cross section if the dowel will not snap into place. I suggest making a small test zipper with extra dowel and conduit pipe to determine the exact shape needed before making the real one.
Step 4: Make a Skateboard
Now you are ready to make the skateboard.
Cut seven 34inch x 11inch sheets of the maple veneer (the sheets need to be larger than the final board because there will be waste wood formed on the edges from the bending process). Three should have the grain going lengthwise (easier to bend the short way) and four should have the grain going widthwise (easier to bend the long way).(fig.4a) Be sure to sand off any chipping on the edges so that the wood is smooth.(fig.4b)
Take layer one (grain going widthwise) and apply a coat of wood glue over the surface all the way to the edges,(fig.4c) place layer 2 (grain going lengthwise) on top and apply glue over the surface all the way to the edges then place layer 3 (grain going widthwise) on top. Now stack the 3 glued layers centered on top of the mold.(fig.4d) You can put four tabs of masking tape on the edges of the wood to make sure it does not slide around when you put it into the bag.
Take a large, mesh dishwashing scrubby, unroll it(fig.4e)and cover the mold and wood veneers with the mesh.(fig.4f)This will allow air to flow around the mold and be sucked into the vacuum easily. You do not want to have any trapped air pockets. Slide the finished compilation of the mold, the glued veneers and mesh into the center of the bag-press and close the seal.(fig.4g) Hook up the vacuum and turn it on.(fig.4h) Keep the bag from sucking itself under the maple veneers by pushing the tips of the veneers down when you turn on the vacuum.(fig.4i) As the air is removed the bag will force the wood to conform to the mold. Once all the air is out gently hit the inner concave with the rubber mallet to help bring in the curve.(fig.4j)
Let the wood press for at least 4 hours before opening the bag and removing the bent board. Remove the mesh and masking tape. Now repeat the last steps to apply the final 4 veneers on top of the 3 first ones.
Once the curved board is dry, make a paper template of the shape you want the board to be(fig.4l) and trace it onto the curved wood.(fig.4m) Carefully cut out the shape with a scroll saw.(fig.4n) Refine the shape with files and sand paper and round all the edges.
Locate where you want your wheels attached and mark the location for the holes with a pencil on the bottom of the deck.(fig.4o)Drill the first hole then screw the truck in place. You can then use the holes in the truck as a guide to drill the next holes, guaranteeing they will line up properly. Once the holes are all drilled remove the screws and use a counter sink on the tops of the holes so that the screw will lie flush with the board.(fig.4p)
At this point you can paint and seal the board to help protect the wood and make it the colour you want.
The board itself is complete,(fig.4q) now you just need to apply the grip tape.(fig.4r) Don't peel all the backing off the roll and just stick it on because this will create bubbles. Instead, start at one end and peel off only a little backing at a time, working it down as you go.(fig.4s)
Once the grip tape is on,(fig.4t) you need to trim it to match the edges. Take an old piece of sand paper and rub the excess grip tape on the edges, this will soften it and leave a mark were you need to cut.(fig.4u) Take an exacto knife and run it around the edges.(fig.4v) If there is any little pieces remaining you can use the sand paper and sand them off. Next, feel out where the truck holes are on the top and stab/trim them out with the knife.(fig.4w)
Now attach your trucks and wheels... and you are ready to go.(fig.4z)