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Ski Building: An Overview If you haven't already
done so, read
the note about safety and the disclaimer before you begin.
Building snow skis (or snowboards) is a straightforward process. It involves
the right equipment, like a ski press and a core profiler, materials, some time, and of
course, patience. The basic steps are:
- building the equipment to make a ski, such as a ski press and a
core profiler;
- designing the ski, preparing the materials and pressing
the materials together; and
- detailing, tuning and testing the finished skis.
Below is an overview of the steps:
1. Building the Equipment
The equipment needed to build skis includes:
(i) a ski press, (ii) a core (usually wood) profiler, and (iii) an edge bender
(you can do this with a pair of pliers, too). A brief description of each piece
of equipment is briefly discussed in the following (To find more detailed
information, please click on the links to your left):
Ski Press A ski press squeezes the ski materials to form a ski.
Figure 1 illustrates how the materials (such as plastic, fiberglass, wood and
epoxy) are pressed together to form a ski. Note that a ski's shape is
created by pressing the ski materials against a mold. When the epoxy cures
is leaves a ski with camber and curved tip (and tails).

Figure 1. (a) Ski construction concept. (b) Side profile of a
ski.

The above photo shows an example pneumatic ski press. A ski press is one of the most important pieces of equipment for building skis. Without it, there would be no easy way to apply uniform
pressure
to squeeze all the materials together to form a ski.
A ski press consists of a mechanism (e.g., a firehose filled with air) to uniformly
squeeze materials against a mold. A simple pneumatic ski press can be made
from surplus metal beams, and the mold can be made from medium density
fiberboard (MDF).
Core Profiler A core profiler is used to shape a laminated piece of
wood to create a ski's core. The core is sandwiched between the topsheet and
the base materials (see Fig. 1 above). Below is
a photo of two ski cores that were shaped on a core profiler. In the photo the
profiled cores are being sanded to leave a smooth finish.

Edge Bender Metal edges come in straight segments and they are bent/shaped
using a specially designed edge
bender as shown below:

For example, the edges at the tip and tail of a ski must be shaped to follow the
contour of the ski's base material as shown:

One alternative to using an edge bender is to bend the metal edges by hand
using a pair of pliers. Both techniques are discussed in the edge
preparation page under the construction category.
2. Ski Construction Process
The materials for constructing a ski consists mainly of a topsheet,
composite layers, core, base and metal edges (see Figure 1).
Below is a photo showing the layup process to construct a ski:

An outline of how we typically build a sandwich-construction (traditional) ski is as
follows:
Step 1: Ski Design The design process is the first step.
In this step, a ski is designed and the process takes into account a ski's
dimensions, flex, stiffness, camber, materials, tip/tail curvature, etc.
Once the ski has been designed, the next steps are to cut/prepare the materials.
Step 2: Base Preparation The base material is cut to the
desired shape, and pre-bent edges are temporarily attached to the base using
superglue.
Step 3: Core Preparation Vertically laminated
wood is the most common material of a ski's core. A blank wood core is profiled to achieve the desired
vertical dimensions to determine its overall flex and stiffness. Sidewalls, tip spacers, and
inserts are also attached to the core.
Step 4: Composite Preparation The
composite material (e.g., fiberglass, Kevlar, etc.) is selected and cut to shape.
Step 5: Top Sheet Preparation A topsheet is used
to form a protective layer on the top of a ski, and it's also the layer above
the graphics. For example, graphics can be either printed on the bottom
side of the topsheet material or they can be placed below the topsheet material.
Step 6: Pressing the Ski The prepared materials are then
arranged and placed on top of the bottom mold (Figure 1). Epoxy is used to
glue the layers together. Then the materials and mold are placed in the press
to squeeze the materials together to form a ski. The materials
are squeezed together until the epoxy cures, usually for 8-12 hours at room
temperature.
3. Finishing Process
This final process involves trimming the excess materials after the ski has been
pressed. Additionally, it includes detailing the skis before they hit the
slopes, and of course, proper care and upkeep. One of the most exciting
things about building skis is to test whether they work by taking them out in the snow! 
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