When building without a jig, one relies on a tape measure, clamps, eyeballs, levels, and shims; great results can be achieved this way, but it requires skill and patience. With a jig, the parts in a fabrication are held rigidly in the correct location. If everything is cut to the right size, assembly simply becomes a game of putting everything in the jig and welding it together. The benefits for any fabrication in volume should be obvious. Even in one-off fabrications, a jig can provide advantages that more than make up for the time spent building it.