Rod and Tube Straightness Checker Tool

thingiverse

Have you ever found yourself in need of checking if a rod or tube is straight? Construct this straightforward tool using just a few 608 bearings to rapidly determine if something is even slightly bent. Simply position the rod across the bearings and roll it by hand. If the rod is perfectly true, you won't observe any wobbling at the ends when turned. I created this tool for a friend who's an avid competitive archer. He required a simple way to quickly check if his arrows were bent. The only additional parts needed are four 608 bearings (not rubber shielded so they spin smoothly) and four #4 screws, each one inch long. Print the bearing support four times to create two pairs of bearing blocks. There is a 0.4 millimeter gap between each bearing and the supporting plates, making it best to print at a layer thickness of either 0.1 or 0.2 millimeters.