Spindle Finishing for Heavy Burr Removal
What type of automated finishing machine do we need?
Q. We have a non-flat handle type machined steel part with very large tough burrs produced by a broaching operation. Our vibratory process rolls the burr, but does not remove them. What type of automated finishing machine could automate this?—R.L.
A. Robotic finishing will work, though it is expensive. An alternative mass finishing process that can remove large, tough, rollable burrs is a spindle machine.
The spindle machine holds and plunges the part into a rotating bowl of mass finishing media. The spindles are programmable for rotation and pitch angle and can rotate in either direction and position to dwell in one area.
The bowl rotates, forcing the media to the outer side. The spindle positions the part into the area of media concentration. The energy of the bypassing media is intense and the spindle can position the burr precisely into the high intensity area.
Spindle finishing is a good process for maximum burr removal. Spindles are used in the gear industry where the root of the gear may have a different radius requirement than the tip of the gear. It is also used in dry finishing, allowing the media to hit the part with the intensity required to do the work.
Originally published in the July 2015 issue.
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