These features can be partially checked by using a shadow graph and rotating a blank of the part to be inspected identifying the fluctuation during rotation. It is very difficult to read a comparator to the fourth place decimal and the inability to steady the part effects the reading greatly.

Also used is a process of holding the part to be inspected in a collet and using an indicator to read the T.I.R. This inspection process relies on the collet and and machine to be T.I.R. accurate within .0002. This is possible but does need constant monitoring and the process is very time consuming.

• Slow set up times.
• Run out between head and body.
• Poor die life from the blank not entering the die straight.
• Mismatch of the die parts with inserts bought for later die assemble. Run out of only .001 is enough to cause harm in many of today's applications of header die inserts. .001 face run out is enough to not allow for inserts to fit together properly causing flashing.
• Bent blanks. Run out of only .002 between a sizing portion and the relief of an extrusion is enough to bend the blanks.
• Bold head failure. .001 face run out is also enough to cause flange head applications to fail due to bolt heads popping off or failing to engage properly.

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