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Advantages
There are advantages to using wood and fabric instead of metal. Wood is easy to work with, more forgiving during construction and doesn't require as many special tools or skills. Wood is lightweight and requires no rivets that can cause drag. Fabric is also a lightweight solution, and applying it yourself can save as much as $10,000.
Preferred Wood
Some of the more common woods used in aircraft construction are white pine and spruce; ash and fir are used to a lesser degree. It's important to use wood that is free of knots or irregularities and has a tight grain with a minimum of six rings per inch, though as many as 12 per inch is preferred. Straight grain improves the strength, which is a very important consideration. Kits will sometimes use tested plywood, but if you are unsure of the quality, it's best to obtain a structural analysis from the supplier.
Preferred Fabric
Cotton was the fabric of choice until the 1960s, but now polyester fabric is commonly used because it is easier to work with than cotton. The fabric is available in light, medium and heavy-duty weights, and the weight used must be considered in relation to the overall weight of the airplane. The fabric must be shrunk properly and evenly. Too tight or uneven, and you risk damaging the structure. Using high temperatures can cause the polyester threads to melt.
Maintenance
The fabric should be replaced every 15 to 20 years. Most of the work is in the preparation. When recovering the plane, it's wise to cut around items that need to be returned to the same location, such as inspection plates and reinforcement patches, so they are easier to replace. Once the fabric is removed, inspect the framework for wear, damage or dings, and repair it as required. Clean off any oil or contaminants, and remove all rust before priming. Cover any sharp edges with reinforcement patches.