(updated) "good enough" 3d printable Caliper tool

This is the final model of my caliper project. This design improves upon the last version as the measurement lines have been widened to improve printing quality. Tolerances have been adjusted to allow the two halves to slide together more easily. The overall quality has been improved by adding fillets on the edges and sliding rails. The interior dimension gauge now measures between 0 and 20 cm instead of the 3 to 20 cm measurements the previous version could measure.