WoodSkills Issue 02 - Page 67

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All of these methods are tried and tested and produce very good results. The rest of this article, however, will focus on laminating using a vacuum press. This is the method whereby the layers to be laminated are placed over a male former which is then placed into a reusable thick plastic bag. The bag is sealed and a vacuum pump attached.

The pressure applied when the air is pumped out of the bag is about 10 tonnes per square metre (15psi) and is enough to produce a very good and repeatable result. The application of uniform pressure over the workpiece, for a well-designed former, removes the difficulty this can pose with other methods.

For single items and small batch production it has the advantage over the traditional two-former process in that only a male former needs to be made. This is considerably cheaper, quicker and easier to engineer than manufacturing corresponding male and female formers.

The equipment involved in using a vacuum press is quite pricey, but if you intend to do quite a few laminations during your woodworking life, then it is an economical investment and space saver in the long run as it can also be used for all of your veneering work and packed away when not in use.

In the following discussion, flexiply or bendy ply refers to thin 3-ply 1.5mm birch plywood with the characteristic of bending easily. This is often referred to as aircraft plywood or aeroply.