Check your power lead screw bolts

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moditwell

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I have never liked to use the power feed on the mini lathe. It was noisy and it just didn't feel good. The saddle also did not move very smoothly towards the opposite end of the chuck, it jammed up against the lead screw. Because most of the work piece is short, I never used the entire 17" length bed and the lathe was left like this. Then one day I opened up the controller cover and saw the horrible screw thread that holds the pillow bearing which supports the lead screw. It was very crooked and once tighten, it bites on only one small, area of the bearing mount. The more you tighten the bolt, the more the mount moves away from the correct position and the lead screw becomes skewed or slanted. This is what caused the binding and that is also why so many mini lathe users experienced broken plastic gears.I stripped the entire mini lathe and re drill the holes. Once done, it was smooth and very quiet. The saddle could move the entire length of the bed easily. It was one difficult project to correct just 2 holes using Helicoil.
 

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And this is an example of why these lathes are partly seen as a "kit" project that has to be finished by the end user to end up with a good machine.

Don't knock me for saying this as I am a Mini-Lathe user myself. I actually have liked the process of continually improving what I have. It's a good way for a hobbyist to learn all about a machine and all about the things that make the process of machining more successful. But then I am one who likes repairing things and making things and inventing things. My goal is learning about "this stuff" more than about making flawless models or "100-point" projects.

Congratulations on finding another point of concern on these machines and thank you for posting a well written and illustrated thread.

--ShopShoe
 
Almost every area that is not exposed will have some kind of corner cutting work. But like what ShopShoe says, its works like this gave us opportunities to learn. I can tell you all users of mini lathe that the plastic gears are strong enough for all jobs if the machine is not binding. Later i will share one more problematic area that leads to plastic gear self destruction.
 
You need to fill up the hole with some kind of plug before you redrill. The plug needs to be a softer or same material as cast iron
 
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