Mini Lathe 3" Chuck Jaws Holder for grinding service.

thingiverse

I recently followed a video's instructions to modify my mini lathe's chuck, which had a runout of around two thousandths. The video suggested using an outer ring to hold the jaws in place and create a makeshift grinder service. Unfortunately, the outcome was far from ideal. Instead of resolving the issue, the modification increased the runout to 10 thousandths. This was not what I had hoped for, especially considering the amount of time and effort I invested in the project. The main problem lies in the design of my lathe's jaws, which have a slight amount of play. As a result, an external grip would only exacerbate the issue. A more effective solution would be to incorporate a grip that is naturally aligned towards the center of the chuck. In search of a solution, I stumbled upon an old video featuring a gentleman from the 1940s who had designed a system to address this very problem. Inspired by his ingenuity, I decided to create and print a custom part for my mini lathe. With some trial and error, I was finally able to rectify the situation and restore my chuck to its former glory. In sharing my experience, I hope to prevent others from making the same mistakes I did. Warning: If your 3D printer is not precisely calibrated, do not attempt this project. Proceed at your own risk.