Hi,

I know the question is old. I reread many material on the net these days. Now the case is the following:
I started building my next machine, this one will be for myself.

Definitely i would like a rotary axis. This axis will serve mainly for the following purpose:
-3d pieces made from wood with dimensions no more than 750 x 50 x 50 mm.
-cutting teeth on aluminum and plastic custom pulleys max 150mm diameter. It would be great if i achieve this.

Now i know of the types and goods and bads. I don't want any bads. So the only possible design i see as possible is similar to the http://www.theinturn.com/, which de facto seems to me the best diy solution.

So i would like to achieve something similar on smaller scale, as it will not be mounted on a mill. However my machine Z would be very ridgid, so i believe if mounted at the proper place i can even do some small lathe jobs, tools mounted on Z. Again-aluminum, plastic and wood. i dont expect to mill steel.

I don't have mill or the skill, though our forum friend Jeff lives very near and has surprising workshop, machines and knowledge. Good for me.

My conclusions till now:
-head will be best to be 5C collet system in my case
-singular or multiple HTD belt driven
-brake is a must
-hi encoder count 750w or 400w servo is a must. leaning towards the second.


Now before i say more, i have small hobbymat lathe that i am very inclined to fit directly on the top of the table or split it and use the main parts fitting it somewhere or combination of these two. Cause it seems it will be the cheapest, as i have it already and what i need to do is fit servomotor and change the pulleys and belts with HTD 5

Or if i start it from scratch, i will need to machine some parts and most importantly find suitable big cheap roller bearings for the head stock / 5C /,

But my biggest question is how to brake the thing on the cheap. I assume a disc from something and ...


And what is this stuff called dynamic balancer the Inturn 4rt axis implements. I would not need it i assume.