Topsheet Overview The topsheet basically serves as a
platform for the graphics or to protect underlying graphics.
Topsheets come in a wide variety of plastics ranging from polyethylene to P-Tex.
Typically the material is very thin (1-2mm) and has protective masking on one
side. This masking prevents epoxy from bonding to the exposed side
of the topsheet and peels off during the finishing process to reveal a nice,
shiny surface. Other
materials that can be used as a topsheet include wood veneers, fiberglass, and
other composites.

However, skis can be built without a topsheet. This can be done
by using composites or cloth as the uppermost layer of the ski's construction.
The epoxy within this layer cures to a nice hardness and will act as the
topsheet. But the appearance of ski suffers and the epoxy is exposed
to UV radiation. We recommend that a proper topsheet is used for ski
construction. It adds a nice element to the finish of a ski.
Preparation As with the composites, cut the topsheet to overlap the ski's
edges. We generally use as large a topsheet as possible to
guarantee adequate coverage of the ski. The excess will be trimmed
and cleaned in the finishing process.

If the topsheet material did not come with a masking film, you can
easily make your own. It is recommended that the topsheet is always
protected. Epoxy will get onto the topsheet during layup and will leave a
messy appearance unless there is some sort of protection. As with the base
material, the topsheet can be protected from epoxy during layup by simply
covering the exposed surface with tape. A low adhesive tape works
best because of its ease of release.

After the ski has been pressed, this masking layer is removed to
provide for an smooth, epoxy-free topsheet.
Remember that the topsheet graphics can be done in the same manner as the
base graphics.
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