From my experience the best material for the top layer of a custom snowboard box is a sheet of polycarbonate. (Note 2010: HDPE – High Density Polyethylene – is a better solution than polycarbonate if you can come across some. HDPE is a bit softer and won’t fracture as easily as polycarbonate, it’s also slightly less expensive. It should be available at your local plastics supplier, ask for pricing on sheets of 1/8″ thickness.)
Polycarbonate is a particular type of plastic which can be molded into any shape during production. The final product is resistant to both temperature and hard impacts, making it both strong and durable through the winter. In fact, you probably have some in your home or work place in the form of CD’s, DVD’s, water jugs, business signs and much more.
The problem with polycarbonate is that it is generally expensive to purchase in small quantities, and only available through industrial plastic suppliers. However, If your going to purchase lumber and invest time into a decent snowboard box, its worth throwing down a couple extra bucks for a decent top layer that actually works and lasts! After all, this is the one part of the box you don’t want to skimp on.
A quick call to your local plastics supplier will get you general pricing for polycarbonate. You’re going to want to ask if they have it available in sheets. Sheets come in various thickness, as well as lengths and widths. Naturally, the thicker, the more expensive. Ask for pricing on sheets of 3/16″, 1/8″ or 3/32 thickness.
The boxes I built were used for roughly 50 sessions until one of the top sheets fractured, they have since been replaced with HDPE top sheets (see comments below). They were each built using 1 sheet of 12″ x 72″ x 1/8″ thick polycarbonate that I purchased for around $25 each, however price will definitely vary, and I was able to pick them up locally to save on shipping. The $50 investment on a good top coating is what made these boxes practically perfect. You will find your that board will slide across cold polycarbonate like a hot knife through butter. Just make sure to counter-sink the screws into the plastic when attaching it to your box, it’s also a good idea to sand down the edges of the plastic. Snags = Bad.
(Above) The snowboard boxes in winter 2011 with polycarbonate top sheets.
(Below) The snowboard boxes (and a new 2 x 8′ butter box) in December 2011 with the new HDPE top sheets on them. The serious lack of snow is making it a bit hard to session them right now though…
Installing the HDPE (or polycarbonate) to the Box
Items you will need:
- 1/2″ stainless flathead screws, similar shape to this.
- Painters edging tape, or other easily removable tape.
- Power drill
- A counter sink bit (photo)
- 3/32″ drill bit, or something a bit smaller than the diameter of your screws (photo)
- Sandpaper, 80-120 grit
- Lay the HDPE across the box and align all 4 corners.
- Tape the HDPE down with removable tape in a few areas so it doesn’t slide. I used painters edging tape.
- Using your 3/32″ drill bit, drill through the HDPE and about 1/4″ down into the box. I drilled holes about 1″ from edge of box in all 4 corners as well as every 2 feet or so along box. (see photo, refer to red dots)
- Using the countersink bit, countersink the holes you drilled in the HDPE just enough so the screw heads will fall slightly below flush. (see image)
- Insert screws into your pre-drilled holes.
- Remove tape
- Sand edges of HDPE so they are rounded. Sanding the edges of the HDPE is essential! Not only will you snag the edges much less, but if you leave the edges “sharp” you risk damaging your clothing. I slid against the unsanded HDPE edge the first season I made these and sliced my jacket open from the friction!!
Hope that helps. I’m sure there are other ways to successfully attach the HDPE but this was my method. This method will also allow you to easily remove the HDPE from the box if you need to make repairs or what not. Let me know if you have any questions.