Introduction: Building a Longboard -the Complete Process
This project started as a fun idea and some concept art, and turned into a really great summer project with an awesome, useful final product. I spent a great deal of this summer working with my chemistry teacher (known as Doc), who is an excellent woodworker and has his own shop; we worked on this board between jobs. Doc's expertise and tools were very valuable in this build.
Like I said, this project was well worth it for the result, longboarding is a really fun method of transportation. In addition to that, through this project I got to branch out into many new areas I hadn't yet explored. This project introduced me to fiberglass, lamination, and high gloss polishing.
Throughout this Instructable I will mention all the tools and materials I used. I'll also try mention alternatives tools that can be used if you don't have access to the ones I did.
Step 1: Design Process
Longboards come in all sorts of shapes. Since the purpose of this board was just fun and non-intense transportation, I went with a cruiser-style shape. I was fortunate to have a friend who had a board similar to the one I had imagined, so I took a tracing of the contour and just modified it a little to get my final shape. The board ended up about 9" at the widest point and 37" long. With patience you can freehand the shape, but a model board is very helpful to get an idea of what you want.
One of the first things I did was design the pattern for the underside of the board. I was excited about these circuit-board designs I had discovered, and I threw together some very colorful concept art in Photoshop. When I got to making a full scale pattern I ended up just using the concept art as inspiration and free-handing the design. In the planning process, I also had to think about the shape that the board that had to be laminated into, which leads us to the form.
Step 2: The Form
I wanted the board to have a lifted tail and a subtle curve upwards on both long sides. The solution I came up with was to make a solid block with the negative curves cut out of it so that in a vacuum bag the blank (the unshaped board, or everything that is glued up together) could be pressed down onto the form and forced into shape. I glued up a couple pieces of MDF and used screws to clamp it together. I chose MDF for the form because it is easy to shape, flat, and cheap. After trimming up the block, I sketched out the shape and used my eyes and an angle gauge to decide what angles to trim off. It was a lot of sketching and drawing lines and measuring because there wasn't a great way to figure it all out. I ended up needing to cut off about a 35 degree angle (I don't quite remember), at a slant along the length of both sides. I accomplished this by screwing plywood strips to the back at the same slant and running the whole thing vertically across the table saw. We cut off the taper for the tail using the bandsaw, and smoothed over all the edges with a rasp. If you don't have a table saw you'll have to get creative, but with a mixture of a hand saw, a rasp and a sander you could probably get something close. But just find someone with a table saw.
This left us ready for the glue-up.
Step 3: The Glue-up
The board is made up of three layers of 1/8 inch baltic birch plywood, with a layer of fiberglass in between each. From all my research, everything said to use baltic birch, so we ordered a sheet from our wood supply place. It cost $16 for a 5x5 sheet. I cut the three pieces of plywood bigger than their final dimensions, and tapered the ends on the chop saw so that the wood wouldn't have to bend over a compound angle. As for the fiberglass, Doc happened to have a roll of airplane-grade fiberglass from an earlier project, so I got that for free, part of the reason this project was so inexpensive. We cut the two pieces of fiberglass cloth to size. You can find fiberglass materials at most hardware stores or a specialty store, like a plastics supplier.
We waxed up the form with beeswax, and laid out lots of wax paper. Also gloves are absolutely necessary when working with epoxy, and an extra person is very helpful. Fiberglass is composed of fiberglass cloth, sandwiched in two layers of epoxy, so the glue-up was a matter of laying down plywood, a layer of epoxy, cloth, epoxy, plywood, etc... Mixing the epoxy in separate batches is easiest, and read all the instructions with your specific epoxy. Try to pat down the cloth before pouring more epoxy over it, and make sure to squeeze as many air bubbles as you can out before you put on the next layer of plywood.
Once the blank was all assembled on the form, we tacked in three small nails through the blank to keep it from sliding around. Then we covered the top and bottom with wax paper and laid it in the veneer press. This press is basically a bag on a frame that folds down onto a table-top and is attached to a vacuum. With minimal difficulty, this press sucked the blank right down onto the form and kept it there until we pulled it out 4 hours later. Since I do not know anyone else who has or has access to a veneer press, a sealed vacuum bag with a hand pump should also work for this type of glue-up. These bags can be made or purchased. Look for lamination vacuum bags or veneer vacuum bags.
We had kept the extra mixed epoxy as a gauge so we knew when it was hard enough to remove. Although it was advertised as 15 minute setting time, it still took hours. When we pulled it out we wrapped it, on the form, in band clamps to let the epoxy cure in shape for about a day.
Step 4: Shaping the Blank
When the blank came off the form I traced the pattern for the shape of the board onto the underside of the blank. I did this by cutting along half of my original paper pattern and tracing that onto one side of the board. I flipped it, and traced the other half to create a symmetrical shape. I cut this out with a jigsaw. There is really no better way to cut it out. Then I moved to the handheld belt sander to smooth out the curve. A normal sander would work, but optimize for the belt. Whenever you are cutting or sanding fiberglass a respirator is very important. After getting the curve smooth, I routed a small round-over on the edges (not totally necessary) and went over the whole thing with 150 grit on the orbital sander.
After figuring out where I wanted the trucks, I placed one down and cut a piece of plywood that fit in between that and the other one. Then by holding the trucks against the board it was easy to make sure that they were straight and lined up with each other. I think we got it just about perfect, but it honestly wouldn't have mattered if they were a little off. I marked out the spots and drilled and countersunk the holes on the top of the board. We didn't back the drill bit very well and we got some tear-out. Since it was on the top it wasn't a very big deal and we fixed it up as best we could, but we definitely could have been more careful. At this point we threw the trucks on and took it for a test ride, It worked great for a first run! But my shoes left lots of footprints on the unfinished wood... back to the sander.
Step 5: Painting the Design
Again, the design was one of my favorite elements of the board. I planned to spray paint it in a mixture of red and black, to compliment the color of the wheels I had. This meant I had to mask off the design in tape. I covered the whole underside with masking tape and attached my pattern to the tape with some spray adhesive and more tape. Then I meticulously cut out the whole design through the paper and tape with a straight edge and a razor blade. When the right sections of tape had been removed, I moved to spraying. I laid on a coat of red and added black splotches and flecks until I liked it. After plenty of time to cure I removed the tape and it looked awesome! The masking tape did a fine job of keeping the paint in the lines.
Step 6: Finishing the Underside
After the spray paint dried, my plan was to wipe on stain around the lines, but Doc convinced me to spray the stain instead, since he was worried that the wiping motion and the alcohol in the stain would mess with the paint job. Him being a chemist, I believed him. We usually spray using gravity flow spray guns hooked up to the air compressor. If you choose to wipe the stain, just be careful. Since the stain was sprayed the grain doesn't pop quite as much, but I can live with it.
We applied one last layer of fiberglass to the underside for protection, and to provide something to polish-up. In the process of polishing (which comes later) you want the surface to be as flat and smooth as possible. Our solution was to spread a little extra epoxy on and then stretch a piece of wax paper over the whole surface. After giving this a day or so to cure up we removed the wax paper, cut off the excess fiberglass with a razor, and sanded it down flush with the edges. Now for the top :)
Step 7: The Top
Once the edges of the fiberglass had been cleaned up, I gave the whole top and sides an extra sand with 150 grit. I decided that I wanted some stripes down the top, which was a good decision because the grip tape was clear and the top would have been kind of dull without it. We found a red stain in our magical-cabinet-of-a-thousand-stains that worked well with the stain I had already used on the bottom. You could also do a spray paint design on the top if you desired. We tried out all the stains on some scraps of baltic birch to make sure we liked the color. Stain doesn't mask well-- it usually bleeds under the tape. We decided we didn't care because it would be under grip tape anyways, but I definitely wouldn't try to do an intricate design with masking tape and stain. After we wiped on the red, we gave the stripes a coat of polyurethane with a detail spray gun, the idea being that the polyurethane would prevent the other stain from soaking into those areas. We wiped the brown stain onto the top and the unfinished edges of the board. I also laid a coat of polyurethane on the edges, since they won't be covered with grip tape or fiberglass.
Step 8: Polishing
Polishing out the epoxy was tricky. When the epoxy cured, it had developed what seemed to be air bubbles filled with dust. This might not have happened if we had used a blowtorch to help set up the epoxy and cure it faster, or if we had put the thing back in a low pressure vacuum bag to squeeze out air and get it flat. Either way, the layer was kind of bumpy and the little pockets didn't polish out. We'll have to come up with something better next time.
The polishing process starts with a rough sanding pad on the orbital sander (probably around 150 grit) to get the whole surface as flat as possible. It scuffs it up quite a bit, as you can see in the picture, but as long as it's flat, it's good. Polishing is basically the process of replacing big scratches with smaller scratches. I then worked my way through 170,180, 350, 500, 800, 1000, 2000, and finally 4000 grit. Most of these were sanding pads which I dry sanded with on the sander, but when I had to use sandpaper, I wet sanded with some soap and water.
After 4000 grit, I put some automotive rubbing compound (you don't need a ton) on the buffer and ran it over the surface until it was all dry. Then I did the same with the TurtleWax. You don't need a buffer, just a lint free cloth and plenty of elbow grease will buff it out well.
At this point the surface was incredibly smooth and as shiny as the epoxy was gonna get. I feel like several coats of polyurethane would have polished up a lot better and been free of blemishes, but the fiberglass was worth it for the extra strength.
Step 9: Grip Tape and Trucks
I ordered a sheet of grip tape on amazon for around $5 and it showed up pretty fast. Grip tape generally comes either clear or black. I went with clear because I wanted to highlight the wood and I thought it looked better. You should get help on the grip tape because once it's on, it is not coming off. It's best to have extra hands and get it right the first time. We laid it down carefully and used a little wooden roller we found to press it down and get it all flat. After that I cut off the excess with a knife and re-countersunk the holes for the trucks. It's pretty important to cut all the extra tape off so that the edge is flush with the side of the board. This way it's very unlikely to peel off.
Attaching the trucks was very straightforward, since the holes were already there. The trucks I got for free from a friend, and they were in great condition except that all the bold heads were half stripped. I found new ones at the hardware store and also got nylon lock-nuts instead of normal nuts. The original bolts had lock nuts and they help prevent the trucks from wiggling loose. At this point the board was ready to ride!
Step 10: Final Thoughts
I have loved riding this board and the process of making it was really fun. It's really beautiful and rides well. I only had to spend about $60 on the whole project, but I was lucky to get a lot of things free. The clear grip tape I like except that you can see where your feet sit because the dirt accumulates in certain spots. You might want to consider that if you are planning to go with clear. Also I wish I knew exactly why I got all the spots on the bottom coat of fiberglass so I could fix it next time.
I hope you found this Instructable useful and please comment if you have any questions.