Problem with manual machining on a WABECO F1210E CNC mill

[dynosor]

I bought a used WABECO F1210E mill without the CNC controller to use as a manual machine. My problem is that the Y-axis travel is reversed from conventional manual mills: Clockwise rotation of the handwheel moves the table towards the operator.

This machine has ballscrews and WABECO have quoted me 420 Euros to deliver a lefthand ballscrew. Have any of you encountered this reversal as a problem, or am I silly for using a CNC machine manually?

What is involved in replacing the Y-axis ballscrew?

I may reverse the existing Y-axis ballscrew rotation using a custom made double gear train, or are there easier ways to reverse the table travel?

The previous owner used the mill under CNC control and did not notice this reversal in manual mode. I did not ask which way the table moved in the Y-axis before I bought it, as all mills I had touched before moved the same way...

Thanks

[sansbury]

In general, ball screws are not considered a good thing on a manual machine because they are not self-locking. In other words, as you traverse on the X axis, the Y axis will creep out of place unless you lock it from turning.

Acme-type screws have enough friction and a steep enough lead pitch that they hold position against such forces on their own. You might be better served by un-CNCing the mill completely if you really only intend to use it manually. Otherwise if it is in good shape I'd want to keep it as-is and simply rig a control for it. Either way Wabecos are really sharp machines and I'd want to treat it right.

[dynosor]

Originally Posted by sansbury In general, ball screws are not considered a good thing on a manual machine because they are not self-locking.

You are right about ballscrew friction. I have taken all the slack out of all three slides by tightening the gibs and this has raised the friction enough to prevent creep (I hope). Don't want to de-CNC it...

[sansbury]

You could make an adaptor plate with a belt and pulleys or gear pair rigged up to reverse the direction you crank the handwheel.

[dynosor]

Originally Posted by sansbury You could make an adaptor plate with a belt and pulleys or gear pair rigged up to reverse the direction you crank the handwheel.

Thanks. This seems to be the direction I am heading. I have ordered two 50 mm diameter gears and now have to execute the plan...