Friday, October 25, 2013

TECH TIP - Changing Cutting Bit Position for Best Results

Optimize the burr conditions on the tube squaring operations. How the tool bit is mounted can shift the .005" burr from the ID to the OD (or the OD to the ID). The balance between the ID and the OD burr conditions (even though they are small) can be shifted by changing the shear cutting angle of the tool bit. 


Tri Tool DURABITS® for the tube squaring are ground with a high shear angle to minimize the residual burr on the ID of the tube and make the chip go to the outside. However, by mounting the tool bit to use the outside part of the cutting edge, there is less effective shear which will reduce the OD burr. Moving the bit as far "out" as possible (the tip of the edge must remain inside the bore of the tube) will provide the most shear action for minimum burr on the ID of the tube. Using the 301E or 301SP for tubing with an ID greater than .50", a tool bit can be mounted backwards in the tool bit holding slot (with the cutting edge away from the centerline) for even greater shear action. Relatively small changes will sometimes make a difference so experiment with what works best for you.