Summary
Skateboard decks come in a variety of shapes, sizes, and materials, but which one reigns supreme? Through finite element analysis (FEA) and material comparisons, it seems like wood decks have proved to reign supreme due to its great balance between portability and structural integrity, giving riders a comfortable and safe ride wherever they may be. The technical report can be found here.
Design Considerations
A cruiser type of deck was chosen due to its relatively small form factor and its ability to turn at tight angles compared to longer boards. The overall dimensions are 32 x 9.5 x 0.5 in.
To properly analyze this deck, it is assumed that the user goes up to 180 lb. of weight, has US shoe size of 12, and requires that the deck have a safety factor of 3. The board also must not have a vertical displacement of more than 0.375 in.
This person’s feet will be placed in between the base of the trucks as shown in the picture to the left.
Material Choices
To test out a variety of common materials and see which is most suitable, aluminum 6061, Plexiglass (PMA), and maple wood are to be analyzed.
After a preliminary round of FEA and weight analysis given the same dimensions, wood turned out to be the lightest. Additionally, wood is a more suitable material for skateboard decks because it is an insulator and handling the board during extreme weather conditions will not cause discomfort to the user’s body (the same cannot be said for aluminum). When compared to Plexiglass, wood is superior due to its material properties and its surface repairability. Acrylic scratches easily and cannot be fixed easily, whereas scratches on wood can be covered with other wood substances found in hardware stores.
Finite Element Analysis Results
For FEA, a pin and roller joint were used for the truck contact area for the back and front trucks respectively. Gravity and the user’s 180 lb. was distributed on the contact area between the deck and the size 12 shoes.
It can be seen that the applied stress by the weight and placement of the feet is very low compared to the wood’s yield strength, giving it a factor of safety of 16. Furthermore, the displacement of the small is close to zero at 0.004 in.
Design Optimization
To further improve the design of the board, a slot was cut through the middle of the board where there was little stress and strain concentrated on the board so that the weight can be reduced to 1.97 lb from 2.15 lb.
