Up and down milling Flashcards
Q: What is backlash in a milling machine?
A: Backlash refers to the lost motion or play in a mechanical system, where the maximum distance a system can move in a direction without applying force.
Q: What is the effect of backlash on climb milling?
A: In climb milling, backlash can cause the workpiece to “jump” into the tool, which may break the tool and create dangerous shrapnel.
Q: Why is conventional milling preferred on manual machines?
A: Conventional milling is preferred on manual machines because backlash can cause problems in climb milling, making it unsafe.
Q: How does chip formation differ between conventional (up) milling and climb (down) milling?
A:
In conventional milling, chip width starts at zero and gets thicker.
In climb milling, the chip starts thick and reduces to zero.
Q: Where does the tool meet the workpiece in conventional and climb milling?
A:
In conventional milling, the tooth meets the workpiece at the bottom of the cut.
In climb milling, the tool meets the workpiece at the top of the cut.
Q: What are the power requirements for conventional milling versus climb milling?
A:
Conventional milling requires more power.
Climb milling requires less power.
Q: How does tool wear differ between conventional and climb milling?
A:
Conventional milling leads to faster tool wear.
Climb milling results in slower tool wear, with some tools lasting 50% longer.
Q: How does tool deflection differ between conventional and climb milling?
A:
In conventional milling, tool deflection tends to be parallel to the cut.
In climb milling, tool deflection is perpendicular to the cut.
Q: What is the force direction on the workpiece in conventional versus climb milling?
A:
Conventional milling has a lifting force on the workpiece.
Climb milling applies a downward force, which simplifies work-holding.
Q: What type of milling is usually used on higher-end CNC machines?
A: Climb milling is almost always used on higher-end CNC machines.
