Hi all

For cutting to size an aluminum tube with 17mm OD and 15mm ID, I was thinking of using two annular cutting edges, one stationary and the other one moving. To have a better cutting quality I want to move the moving cutter not just on a straight line but on a circle. Suppose there is a round die holder that rotates around its own centerline and cutting die is placed on this disc but centers are 0.5mm away. Now if die holder rotates a full turn, tube which is passed through stationary and moving dies will be cut. Of course there will be a mandrel which will support inner surface of tube to avoid distortion.

For this machine I need a mechanism for turning the die holder exactly one turn. Any inaccuracy will cause problem in ejecting the cut tube and feeding for next cycle. Considering clearances between tube and cutting die and mandrels I think 2 degree error can be acceptable. I prefer not to use servo motor and such devices but simple mechanical mechanisms. I was thinking of "mutilated gears" and "geneva wheel" for this purpose. As for Geneva wheel, I think it's not suitable for power transmission and as for Mutilated gears I'm not sure if it's enough accurate and if there is any solution for decreasing impact. Both these mechanisms have advantage of having continuous input (which can be provided by a simple motor and flywheel) and also dwell period which can be used to feed the tube for next cut for automation (of course single strokes are acceptable).

I would be very happy to have your opinion in this respect and of course any ideas.

Thanks in advance
Reza