VII. Test Fit

80% of the time, it works every time.

This could be considered something of a corollary to forcing it. If you ignore this rule, you’ll often find yourself in a situation that requires breaking that rule as well. When two different parts must interface with one another - often in a very permanent fashion - we would be well advised to test their fit prior to their more permanent attachment.

In the majority of cases, you may find that your work meets your specifications within suitable tolerances and that everything fits as well as it should. With practice and proficiency, you may even be tempted to skip the test fit and move straight on to the real thing. You may find yourself in a rush to reach the end of a sequence of steps and be ready to be done without testing first. In these situations, try to steer clear of the temptations of hubris and efficiency. Slow down and test the fit first.

If there are small adjustments that need to be made to dial in the fit, it is much easier to finesse two individual parts and carefully creep up on the perfect fit than it is when the glue is wet, the two parts don’t quite make it all the way home, and you’re scrambling in a panic to try and fix it on the fly. When quiet deliberate micro-adjustments might have been called for otherwise, you may instead find yourself in need of taking the time you didn’t have to stop and test fit to go back and fabricate two brand new parts to replace the two original now permanently partially assembled and ruined parts.