Go No-Go Gage—customizable— (Tolerance Gage)

thingiverse

This thing can be customized to create a go-no-go gage for verifying distances in a snap. If an object fits snugly into the wider gap, it's not too long - you're good to go! But if it slips easily into the narrower short gap, it's too short, plain and simple. Thus, the gage can be used to determine whether an object meets specifications with ease. When I'm making a batch of (nearly) identical objects, I find it a whole lot easier to use the gage to verify size rather than measuring numerically - it's just faster! For instance, a go-no-go gage is a godsend when I need to make a bunch of wooden parts that are all the same size. I can quickly eyeball them and trim them down with ease. In wood projects, I usually whip up two gages: one with a slightly larger go and no-go gaps for cutting blanks on the saw, and another with the range for the finished item to check my progress on the sander. You can customize the gage to any size that's perfect for your needs. You might need to tweak the input numbers because a printer may create objects with dimensions that are slightly different from what you specified in Customizer - but don't worry, with some experimentation, you can come up with objects that meet your requirements. As a practical matter, I find that using a range of +/- 0.5mm (+/- 1/32") is close enough for most of my projects. As you design gages, remember that the outside frame needs to be relatively large to keep the flexibility of the printed plastic from messing up your measurements - it's all about precision!