In need of a lathe

[Noodles87]

I need a lathe. My question is. Am I better off buying a mini CNC lathe from someone like Syil or Sherline. Or would building it myself be more worth it? Or will a "mini" or "small" lathe even handle what I need?

I need to hold an accuracy of 0.01mm. The maximum diameter of my parts are 35mm. And there may be an occasional time where I need to turn something off center. In that case we're talking 70-80mm max "diameter". I'm not as much worried about speed as I am accuracy. Though speed isn't something I wouldn't mind having. The longest part I'd turn would be roughly 400mm and be bored all the way through holding 0.01mm over its entire length IF possible. But a little less would be acceptable. All...or almost all work would be aluminum. 6160 and 7075. On average parts will range from 20-200mm in length. Average ID's will be 3mm-25mm to be turned. Those not being a straight bore. I need to be able to turn internal and external oring grooves(1mm cross section orings). and some grooves may be as deep as 100mm in a 17.5mm hole. and may need to put internal oring groves in something with as small of an ID as 4mm. I'm looking to spend under 10k Including tooling. Really I'd rather spend more like 5-7k with tooling. Hopefully I'm not being too picky or cheap. Its either that or find someone to amke my parts. Its just...some can be complicated. And if I one need a few of each. It starts becoming REALLY expensive to pay someone else. Especially if I'm prototyping something and will make minute changes and need a few only for testing.

Thanks for taking the time to read this and hopefully can offer me any help. Thanks a lot!

[Noodles87]

If I were to decide to build a CNC lathe. This is the concept I'd be going for.

X axis is at 45° with 8 post tool changer. If I decide to go 30° it will have a 6 post tool changer. I'm trying to figure out placement of a pneumatic tail post. Some other things needed would be indexable spindle, and possibly pnuematic drawbar for 5C collet system. But I havent gotten that far yet.

This layout is similar to the one found at www.cnc-projects.de, though I don't know his actual layout.