Longboard decks are typically made from plywood: anywhere from two to eleven layers, each of usually 2 millimetres (0.079 in) in thickness, composed of birch, bamboo, maple, koa, or oak wood. Cruising Longboard are commercially available in a variety of shapes and sizes. Each variety has certain advantages and disadvantages, which come into play depending technique or personal preferences of the rider.
Decks intended for riding downhill are typically stiff and have a wheelbase of around 30″-28″. Designers and manufacturers aim to make these as stiff and light as possible. The primary three designs of downhill boards are “decks”, “top mounts” and “Longboard throughs”. Each design has its own advantages.
The “drop deck” has a lowered foot platform that sits below the height trucks, as a result, there is a lower center of gravity which adds to stability but gives less traction and maneuverability. Wooden Longboard decks are concave and have foot pockets by the drops. However, some carbon fiber boards feature concavity by the drops instead of foot pockets giving more leverage while turning.
The “drop through” design has cutouts that allow the base-plate truck to protrude through the, thus lowering the deck and providing more stability. In addition to this, through decks decrease grip, as is closer to the axle and moment arm wheel. There is also less leverage truck, which makes turning negligibly more difficult for Cruising Longboard.
“Top mount” are the simplest design three. There are no dramatic bends aside from the foot concave. The sits on top trucks as it would in a street skateboard. Advantages to this design include increased grip and ease of turning; disadvantages include a high center of gravity, which could contribute to a lack of stability.
There are many variations aforementioned designs, including a “double-drop”, which incorporates both a through and down pattern. These are preferable for “freeride” as they are extremely low to the ground, which allows for ease of sliding. Footspace is important because there must be enough room on the board for the rider to form an aerodynamic “tuck”. Downhill are made as stiff as possible to minimize the amount of energy stored in order to mitigate wobbling of the at high speed (known as “speed wobbles”).