Before covering with doped fabric, the structure should be prepared by applying which type of coating?

• A. A protective coating of paint or varnish as appropriate.
• B. Wax.
• C. Oil.
• D. None.

Answer: (A)

Before applying doped fabric, the underlying structure must be sealed with a protective coating to create a smooth, moisture-resistant surface for the fabric and dope to bond to. A coating of paint or varnish appropriate to the material seals the surface, reduces moisture absorption, and provides a uniform base so the fabric’s adhesion and the subsequent dope coat behave consistently. Wax or oil would leave contaminants that interfere with adhesion and can bleed into the fabric, and doing nothing would leave the wood or metal vulnerable to moisture and uneven bonding. So applying a protective paint or varnish is the correct preparation step.