home | about | howto | articles | SB gallery | user gallery | forum | links  

SAFETY FIRST!
(please read)

OVERVIEW
  terminology

EQUIPMENT
  a. required tools
  b. ski press
      - press frame
      - mold
      - bladder
  c. core profiler
  d. edge bender

SKI
CONSTRUCTION
 
a. materials
  b. graphics
  c. ski design
  d. template
  e. base
     edge bending
  f. wood core
     - lamination
     - sidewalls
     - profiling
     - tipspacers
     - inserts
 g. composites
 h. topsheet

LAYUP
 a. preparation
 b. layup

FINISHING

TESTING

VIDEOS
Free Video: Intro to Ski Building (30MB).  Get an overview of the process.



Ski Press

Overview  A ski is made by using a ski press.  A ski press provides high, uniform pressure to squeeze the ski materials together to form a ski.  The basic concept of pressing materials together to form a ski is depicted below in Figure 1.  Pressure is exerted on the top and bottom of the materials until the epoxy between the layers of the materials cures.  The shape of a ski, that is, the camber and the curvature of the tip (and tail), is created by pressing the materials up against a mold as shown below.

Figure 1.  The basic concept of pressing materials together to form a ski.

 

Types of Ski Presses  There are three main types of ski presses: (1) clamp press (2) vacuum press, and (3) pneumatic press.

1. Clamp presses consist of a top and bottom mold as shown in Figure 2.   The ski materials are placed between the two molds, and the materials are sandwiched together by clamping the two molds together.  Some techniques to clamp the molds together include bolts, ratchet tie-down straps, and hydraulic car jacks.  Whatever the clamping method, the objective is to achieve as uniform of clamping pressure on the ski materials as possible.

One major drawback of using a clamp press is difficulty ensuring that uniform pressure is applied along the entire length of the ski.  Additionally, it is challenging to measure accurately the pressure being applied.  Although a clamp press is the most affordable to built of all three types, the quality of skis that it produces may not be the best.


Figure 2.  A clamp press.

 

2. Vacuum presses work on the principle of vacuum (or negative) pressure.  Basically, a “bag” encloses a ski mold and the ski materials.  Uniform pressure to squeeze the ski materials together is created by using a vacuum pump to suck out the air.  Figure 3 depicts a simple diagram for a vacuum press.  Ski materials are placed on a bottom mold, then plastic film is placed over the materials and secured to the edges of the mold creating a sealed cavity.   Finally, a vacuum pump sucks out the air to produce the needed pressure to squeeze the materials together.

For the most part, vacuum presses are versatile, relatively easy to build and provide uniform pressure.  However, the drawbacks are limited pressure (often low) and problems associated with wrinkles and bubbles in the vacuum film.


Figure 3.  A vacuum press.



3. Pneumatic ski presses
are common in the ski and snowboard industry.  Because of their ability to produce extremely high pressure, these presses provide the best results.    A diagram of a pneumatic ski press is shown in Figure 4. In the figure, the press consists of a very stiff frame, a mold and a flexible bladder (or a large flexible hose capable of sustaining high air pressure).  The bladder is  placed between the molds as shown.  Ski materials are placed between the bladder and mold, and by inflating the bladder, uniform pressure is created which squeezes the ski materials against the mold.  Note that the bladder pushes against the frame and mold.

 
Figure 4.  A pneumatic press.

The design and construction of a pneumatic press is more difficult compared to the other two types.  However, a pneumatic ski press produces higher quality skis because of high, uniform pressure.  

We use pneumatic presses exclusively and therefore only discuss how to build these presses.  The first step in building a press is to build the frame.  Afterwards, the press components such as the molds and the bladder are constructed to fit the press.   The following links discuss each topic:

 

  home | about | copyright | disclaimer | contact
SkiBuilders.Com © 2004-2011. All Rights Reserved