The masking tape should be applied to a pre-cleaned workpiece only. It is supposed to be flush with the surface. If the workpiece contains a gem, additionally slide the tape under the prong setting for full protection. For optimum results, complete the welding process with a thin welding seam, low penetration depth and minimum power.

Attention: Do not weld directly above the gem! The masking tape does not protect from any damages as a result to direct contact with melted metal,immoderate welding power or welding time.