Which writing utensil is recommended for marking fastener locations on the assembly?

Using a non-graphite pencil for marking fastener locations on assembly is advisable for several reasons, particularly regarding visibility and material compatibility. Non-graphite pencils typically utilize materials such as colored wax or other marking compounds that make it easier to see the markings against a variety of surfaces without the risk of leaving a significant residue. Additionally, graphite can potentially lead to contamination in sensitive environments, such as aerospace assembly, where cleanliness and precision are critical.

Non-graphite pencils usually provide a clearer and more permanent mark on most surfaces used in assemblies, aiding mechanics in ensuring that all fasteners are properly aligned during assembly. This visibility helps minimize the chances of errors that could arise from misplacement, thereby ensuring the integrity of the assembly process.