Some turning required please

[drumsticksplinter]

Hi Jonathon,

Thanks for the reply.

My assembly will look something like this:



Green = Insert, Red = Bearing, Blue = locknut

I've decided to opt for the 40mm OD just because of the configuration of my machine. The length of shaft past the locking nut will accommodate my pulley, so with a 35mm OD minus the thread pitch (1.5mm to allow the locknut to slide over) will leave me with only 2.5mm wall thickness...

Thats a good point you raise about the tolerance of the ball nut flange (62mm) I will measure the exact OD of my ballnuts and work to that because like you say its ciritcal to be concentric.

Good point with the 2mm shoulder, 0.2mm will be better.

I'm not sold on the idea of an aluminium shaft, admittedly the moment on inertia will be less, but the overall mass of the rotating ballnut assembly with steel components compared with that of the ballscrew (with a rotating screw scenario) is considerably less. I'm using 12.2 NM motors with high voltage drives, I know the torque will drop off at higher rpms, but I only need the machine to move quickly for positioning i.e with no cutting loads. Plus I hope to upgrade to servo's eventually.

27mm bore will be fine through the insert.

True about the locknut, I could probably afford to accommodate another nut.

Very true about wipers on the ballscrews, I'm hoping to have the ballnut assembly fully enclosed with wipers on each end or opt for bellows over the entire screw length, or both...

Lastly, What sort of price would you charge for doing these inserts? Keeping in mind the drawing will change slightly to update the items discussed.

Kind Regards,

Adam.