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Guide

The PVC sandwich

A PVC foam core between two fabric skins makes the deck much stiffer and more resistant to heel dents. Where to put it, which thickness, and how to lay it up.

The principle

A sandwich is a light core between two skins of fabric. Moving the two skins apart gives a huge gain in stiffness for very little weight. On a board, high-density PVC foam mainly protects the deck from dents: heels, knees, repeated pressure.

Partial, deck or full

OptionWhere the PVC goesWho it is for
PartialThe standing zone, from the tail.The best compromise: protects where you stand, without adding weight to the nose.
DeckThe whole deck, laminated bottom.Hard-used boards or heavy riders, a more even deck.
FullDeck and bottom.Maximum stiffness, at the cost of weight, money and work.
MonolithicNo PVC, fabric layers only.The simplest to build; make up for it with more layers and reinforcements.

Thickness and density

Common thicknesses are 3 to 5 mm. The thicker the PVC, the stiffer the deck, but the harder it is to bend over the rocker. Usual densities are around 60 to 100 kg/m³: a higher density resists dents better but weighs more.

Laying it up

  1. Shape the blank allowing for the PVC thickness (the PVC comes on top).
  2. Cut the panels a few centimetres short of the rails, and bevel the edges so they don’t leave a step under the fabric.
  3. To follow the curves, use scored (contour-cut) PVC or thermoform it (heat gun, with care).
  4. Bond the PVC onto the first skin, ideally under vacuum, with a thickened epoxy (microballoons, fumed silica).
  5. Laminate the outer skin over the whole deck.
Good to know: the insert and box areas need higher-density blocks or reinforcements: PVC alone is not enough to take those loads.

Sheets and joints

PVC is sold in sheets (for example 100 × 50 cm). If the board is wider than the sheet, strips are joined edge to edge, without overlap. The bigger the sheet, the fewer the joints.

In the calculator

In step 2, choose the construction and, for a partial sandwich, the length of the zone from the tail (by default the rear half of the board). Enter your shop’s sheet size: the calculator counts the sheets by laying the panels out on them.

Compare partial, deck and full: the calculator gives you the PVC area, the number of sheets and the effect on the budget.

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