Calipers are similar to micrometers in shape but instead of measuring distances, calipers are used to transfer distances between objects. An outside caliper is used to transfer outside dimensions while an inside caliper is used to transfer inside distances. A vernier caliper is an extremely precise caliper (down to \({1 \over 1000}\) inch) that allows measuring / transferring either inside or outside dimensions.

Wrenches are used with threaded fasteners like bolts and nuts. A bolt has external threads while a nut has internal threads and this thread pattern combination allows them to lock together and act as fasteners. Nuts come in a variety of configurations including wing nuts which provide appendages that allow tightening and loosening by hand, slotted nuts that use a cotter pin to lock the nut in place and prevent it from loosening, and lock nuts that also prevent loosening via nylon in their threads. Threads are identified by pitch which is the number of threads per inch.

A ratchet (or socket wrench) is a wrench that applies torque in only one direction with a handle that can be moved back and forth without losing contact with the fastener. A ratchet uses variable attachments called sockets which come in a variety of drive sizes based on the size of the opening that attaches to the ratchet. Sockets with the same drive size will vary in the shape (six-point, twelve-point) and size of the nut opening that attaches to the fastener being tightened or loosened. Smaller point sized sockets are stronger and can apply greater torque while larger point sizes allow easier alignment.

Rulers are used to both measure distance and to draw straight lines. Tape measures are flexible rulers made from cloth or metal and are useful for measuring longer distances and in tighter spaces. Both rulers and tape measures provide similar accuracy, commonly down to \({1 \over 16}\) or \({1 \over 32}\) inch. A steel framing square is made up of a shorter ruler (tongue) and a longer ruler (blade) that meet at a 90° (right) angle. A framing square is often used by carpenters when framing stairs and roofs.

Welding is a high-temperature process that involves melting the base metals in the objects to be joined to fuse them together. A filler metal is used to provide additional material to make up a joint that, depending on the weld type, can be stronger than the base materials alone. Oxyacetylene welding is a welding process that uses a torch fueled with oxygen and acetylene gases. Electric-arc welding utlizes electric current in a safer welding process (it doesn't involve burning explosive gases) that enables a wide variety of specialized applications like stick, MIG (metal inert gas), and TIG (tungsten inert gas) welding.