Chuck jaw grinding blocks

thingiverse

After years of heavy use, the jaws of a 3 jaw chuck can become severely worn down. In extreme cases, like mine, they can even go bellmouthed, causing a rod in the chuck to wobble around loosely. To address this issue, I designed three different devices that preload the jaws. Each device functions by engaging the tapered end of the jaws when they are parallel to one another. This enables the user to trap and clamp down on each device, effectively loading the scroll just as if it were holding a real part. As a result, you can grind the jaw tips into precise concentric and straight lines. Personally, I prefer the three-legged design; that's the one I used on my chuck, and it worked flawlessly. The three-block style is also viable, but it requires more finesse to install. The plasma cut plate part should also be effective, although I didn't have a chance to build it myself. If you're interested in seeing these devices in action, I've posted YouTube videos of using the three-legged design on my chuck and testing its effectiveness afterwards.