will this 4th axis work

[magicniner]

Who will Magicniner contradict next?

As you clearly prefer your information to be of the non-factual variety I'll leave you to it :D

[A_Camera]

Has anyone bought one of these harmonic drive index chuck thingies? Are they any good?

I am sure they are pretty good otherwise they would not be sellable.

Is the lack of a through shaft putting you off?

Yes. That and the fact that it is considerably more expensive.

Who will Magicniner contradict next?

I found his comments very informative and valuable. I don't know what you see was wrong with his comments or choice of words, but I did not find them contradicting, quite the opposite. I would actually be interested in hearing more about his experience and the modifications he did, as well as how he is using it.

So many questions, life is too short for all these questions.

...so why did you ask the last one then? It was pretty rude and unnecessary. His comments were pretty valuable, as opposed to your last question...

[Robin Hewitt]

I...so why did you ask the last one then? It was pretty rude and unnecessary.

Don't worry, he's a Yorkshireman, he's already retaliated.

[johngoodrich]

magicniner, do you have any photos of the mods you have done to your 4th axis. I would like to see it. from your experience with these, do you thinkit would be ok for 4th axis wood milling as is, or a bit of modding

[Jonathan]

It could, but I've been making parts with my "rubber band" for a couple of years, how's it going with your "Doorstop" ?

Well enough:

https://www.youtube.com/watch?v=lVuBEEceWJ4
http://www.mycncuk.com/threads/3341-...illing-machine
http://www.mycncuk.com/threads/11220...-as-a-4th-Axis

Unfortunately I ran the stepper motor on the rotary table into my milling machine column (wasn't looking) last year and bent the worm gear, so I do have another doorstop! I'm now wondering if these are better than the price suggests:

http://www.ebay.co.uk/itm/Precision-...sAAOSwZ4dZHZkC

The problem with the direct belt drive method is the stiffness of the belt is quite poor compared to a harmonic or worm drive. Of course, it can be useful but that depends somewhat on the diameter of the material, your accuracy requirement and other factors. If the rotary table above is any good - i.e. "most" of the backlash can be adjusted out, then that plus a 1Nm stepper motor seems like an attractive option.