The illusive Boxford 260vmc

[irving2008]

Whilst reading the Lenze 534 manual ive come across another requirement....

If a reverse motor direction is required a simple polarity change is required using one of the contactors, however the motor motion must stop before the reverse direction is activated, I will need to incorperate a timer to allow for the motor to come to a standstill before the reverse is activated, I can tune the time once I know how long that takes, I could also introduce electrodynamic braking to reduce the changeover time, I will have to investigate all that before I complete a reverse control but that will be a secondary to getting it moving in a forward direction first...

Rick

Other than CNC controlled tapping, why would you want to change spindle direction? My mill's cutter always rotates in the same direction, there is no reversing facility as standard, probably becuase every cutter I have ever seen (and I know thats not many) cuts in the sme direction. Granted I will be able to reverse the motor from the (yet to be fitted) VFD, but I feel there is an inherent risk in being able to reverse the spindle direction without some interlock.

[Ricardoco]

Other than CNC controlled tapping, why would you want to change spindle direction? My mill's cutter always rotates in the same direction, there is no reversing facility as standard, probably becuase every cutter I have ever seen (and I know thats not many) cuts in the sme direction. Granted I will be able to reverse the motor from the (yet to be fitted) VFD, but I feel there is an inherent risk in being able to reverse the spindle direction without some interlock.

As i said the reverse will be a secondary consideration, and an interlock as you state would be the safe way to go, but i Will be considering it, as it is something that the original control panel had.
When I got the machine the computer side of things had a few problems. To be able to fire up the machine and test ALL.. the functions was what sold it to me, I liked the fact i could just get it home and start milling. Without some sort of manual control I would have been taking a real big chance with quite a lot of money im sure you will agree.. and although I suspect as you have suggested this may be a function that i will not often use, the fact that the Z axis can be tilted through 90deg means I am more likely to use that function with the head tilted.

The real fact of the matter is that I wish to retain all of the functionality of the original machine so it is something I have to consider, and may be of use to someone else, should I ever sell the machine (not likely, but still), not to mention the fact that other people reading this thread may find the reverse interlock system usefull.

Rick