Mitutoyo 050103, Edge/Center Finder, 3/8" Diameter Shank, 0.200" Diameter Tip

Mitutoyo means quality.

My go to edge finder. Very accurate

This is one of those "how did I ever do without it" gadgets. It is nicely ground and seems to be accurate and durable. I use it in the drill press to locate holes that should be precisely positioned. Mount it in chuck with the pointed end down, spin it at about 1000 RPM, and gently push against the side of the point with a small stick until it runs without any wobble. Turn off the motor. The point is now exactly aligned with the center of your chuck. If you have accurately scribed cross lines on your workpiece, you can center the point above them visually. (Magnification helps.) Clamp the workpiece in place, swap out the center finder for a center drill, and you're ready to go. It's pretty easy to get a hole aligned within about 0.005 of true position this way. You can also locate the center of an existing hole by centering it visually or by dropping the point into the hole and moving the workpiece until the point is concentric with the body.The other cylindrical end locates the edges of work exactly. It's useful in a milling machine or a drill press with an X-Y table or vise. Again, spin it at about 1000 RPM, nudge gently until the cylinder spins true (no wobble). Now slowly move your workpiece up to the spinning cylinder. When it just touches, the tip of the edge finder will "step" to one side visibly. At this point, the center of your chuck is offset from the work by exactly half the diameter of the tip (0.100 inch). The point at which the side-stepping action occurs seems to be consistent within 0.001 inch. With an X-Y table, you can now crank in the exact dimension you need.

Good quality. I read other reviews that complained of breakage but I can see that because the edge finder has two working ends, when removing it from a collet care must be taken to avoid having the collet hold one end when you are pulling on the body, causing the body to pull away from the end still inside the collet. Best to remove the collet from the collet holder and push the whole edge finder through the collet instead of trying to pull it out. Or buy single ended edge finders.

quality seems good. easy to use and good value.

Works perfectly, buy this instead of Starrett

Whoever thought of this design is a genius...

You may pay more for this than the Chinese version but it's guranteed to work flawlessly for a lifetime. So why not pay a little more, buy it once, use it with no issues, and just enjoy a quality tool that makes it fun to use.