Bigger 3 Jaw Chuck for the Mini Lathe

My mini lathe came with an 80 mm 3-jaw chuck… but with only a 16 mm bore and limited jaw capacity, it just couldn’t handle most practical parts. Anything like 80 mm with outside jaws or 30 mm with inside jaws and the jaws were only hanging on by a single thread of the scroll plate. Not safe, and not very wise.
So I decided to upgrade. In this video, I’ll show you how I fitted a 100 mm chuck on a mini lathe that was never designed to take one. That meant making a custom backplate, cutting a precise registration shoulder, drilling bolt circles on the mini mill, and finally mounting the new chuck.
We’ll measure the runout, test the accuracy, and see if the lathe can really hold a 100 mm workpiece. Most importantly, I can now pass a 20 mm bar through the bore, giving me a 25% increase in workholding capacity. On a small lathe, that’s a massive improvement.
If you’re interested in mini lathe modifications, chuck upgrades, or just love pushing small machines beyond their limits, this project is for you.

Watch my other videos:
   • Toolmaking Ideas  
   • Mini Mill Ideas  
   • Mini Lathe Ideas  

Timestamps:
00:00 Introduction
00:42 The Problem
01:43 The Plan
02:39 Making the Backplate
03:47 Drilling & Finishing
04:56 The Moment of Truth
05:36 Test & Results
06:17 Final Thoughts

#GreatIdeasCatalogue, #Bigger3JawChuck, #MiniLathe