He's added a fourth axis

[Tom]

I CLAIM MY PINT!

Jeff, the pint's yours! You may have to remind me, but don't be shy!

Ref the angular contact bearings, I'm not really sure. I think the way the big boys do it is to pair a set of single row angular contact bearings opposite each other, and preload them, either next to each other at the chuck end (as a matched pair, with a simple roller at the other end of the shaft), or preloaded along the whole length of the shaft (a non-matched pair, one at each end). I reserve the right to be proven wrong.

As george says, the mini-lathes ship with deep-groove bearings, and the upgrade is to replace them with taper roller bearings. This mod works quite nicely (I've done it), but I don't think you'll see taper rollers in this application on much bigger equipment. I think the mini-lathes get away with it because the loads are low. Which is lucky because the larger angular contact bearings, especially in matched pairs are not cheap.

[Smiler]

Ref the angular contact bearings, I'm not really sure. I think the way the big boys do it is to pair a set of single row angular contact bearings opposite each other, and preload them, either next to each other at the chuck end (as a matched pair, with a simple roller at the other end of the shaft), or preloaded along the whole length of the shaft (a non-matched pair, one at each end). I reserve the right to be proven wrong.

I've done it pretty much as per the video to be honest i.e. an angular contact bearing behind the chuck with a thrust bearing the other side of the plate and preloaded them, a simple bearing holds the other end of the shaft. Works really well for router use and I suppose it would work for light engraving on Aluminium but I'd never try machining, I'd convert a rotary table for that (Mr Kip was kind enough to donate a stepper adaptor for such use).

I'll tell you what was REALLY nice about this project. The fact I designed the plates and cut them on my macine and all the bits, bearings, stepper etc. just fit first time, no filing, no drilling larger holes because one was .25 of a mil out because the dot punch slipped, everything just fit and lined up. I know it SHOULD do that anyway but I still find it all amazing and it was worth doing just for that glow you feel when it all goes to plan. My mate at work Kenny has been doing CNC lathe for many years, most at RR, and he says he still gets the same kick when the bits all just slot together first time every time. Wonder if others do :)

[GeorgeD]

Why are you posting random S**T, It had nothing to do with the original or previous posts...

Its my post is it not?

I find this idea of what he's done there highly dangerous and certainly wouldn't attempt that piece of contraption.

[Smiler]

But George,

Flycutting has been done for many years, probably as long as there have been machine shops, safely and successfully. If there is any danger it's the fact the guard isn't in place so he could film the operation but that's all. You wouldn't think anything of mounting that part in a lathe and machining it, it's the same thing except the tool is moving not the piece (I'd say the fly cutter was safer IMO)

[routercnc]

. . . still gets the same kick when the bits all just slot together first time every time. Wonder if others do :)

Definitely. Made a small box for my Wife's sewing kit some time back. Box jointed all the corners, slipped together a treat, gentle sand - hey presto! Still amazing when it all comes together.

George,
What are you thinking of making with your new machine and 4th axis?