anticlockwise milling and clockwise milling

Milling is one of the most common and most widely used processing methods, and for roughing milling of the various structural components and fine milling is almost by end milling. There are two ways, clockwise and anticlockwise milling, according to the cutting direction. The movement of the cutting edge and work piece is in the opposite direction or same direction, divided into the two kinds of conventional milling and climb milling.

Anticlockwise Milling:

Milling direction and feed in the opposite direction (milling against the feed) is anticlockwise milling; chip caused from the bottom into upper, so we also call it as up milling; Since the traditional processing and milling mostly used this way, so we also called it as conventional milling.

Characteristics of anticlockwise milling:

1. Chip shape is from thin to thick, and cutter afford force from light into heavy, which may prevent the cutter fracture by the impact.
2. Suitable for milling casting black surface.
3. Can be used in the old milling machine, no screw invalid gap movement.
4. More friction, the blade is easy to blunt, short life.
5. Easy shaken, the machined surface is rough, poor machining accuracy.
6. The device is not easy to settle, which is not suitable for milling thin parts.
7. More energy consumption.

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Clockwise milling:

The milling and feed in the same direction (milling with the feeds) called clockwise milling; Due to cutting action is from no-machining face of work piece into down place (chips from thick into thin), so it is called down milling or climb milling.

Characteristics of climb milling:

1. Chip is from thick into thin, cutter affords force from heavy into light, easy to cause fracture by impact.
2. Not suitable for milling castings, forgings, and the surface of the work piece with fish scale shape.
3. The milling machine shall have a gap eliminator, or easy to produce screw invalid gap movement.
4. Processing less friction, longer life of the cutter edge.
5. Easy chucking, no vibration, and high accuracy of the machined surface.
6. The device is easy to settle, it’s suitable for milling long thin work pieces.
7. Less feed consumption.

In most of the milling case, in addition to the casting of the first milling and old milling Lo-gap chopping device need to use the anticlockwise milling, down milling is better than conventional milling.

Cutting Reference Data for End Mills of Various Materials

Effective working solution depends on correct cutters, operation method, and technology.
Usual cutting conditions and major influence factors of CNC machines.

	Introduction	Formula
Cutting Data V(m/min)	Cutting speed is decided by the diameter of end mills and its rpm		V=Cutting speed(m/min) D=diameter(mm) N=rpm of one min of end mills(min-1)
Feed speed F(mm/min)	Feed speed is the speed of relative one of work piece. Feed rate per flute is important for multi-flute end mills.		F=Feed speed per minute z= number of flute f= Feed volume per flute
Cutting depth a(mm)	Cutting depth is the thickness of flute machining on work piece. We always increase cutting depth to achieve its efficiency, but it is too deep to short tool life. It’s better to give proper cutting depth per flute, don’t increase feed rate and cutting depth together.	--	--
Feed rate per flue f(mm/刃)	Once a flute to cut	--	--
Cutting width b(mm)	Vibration caused by diameter of end mill, width of work piece, flute numbers, and cutting width.	--	--

Cutting Speed

Work Material	High Speed Steel	Carbide – rough cutting	Carbide – fine cutting
Cast iron (soft)	32	50-60	120-150
Cast iron (hard)	24	30-60	75-100
Malleable cast iron	24	30-75	50-100
Steel (soft)	27	30-75	150
Steel (hard)	15	25	30
Aluminum alloy	150	95-300	300-1200
Yellow Steel (soft)	60	240	180
Yellow Steel (hard)	50	150	300
Bronze	50	75-150	150-240
Copper	50	150-240	240-300
Hard Rubber	60	240	450
Fiber	40	140	200

Feed volume each side

Working Material			Face cutter		End Mill		Spiral flute flat end mill		Side Cutter		Milling Cutter		Metal gap cutter
			HSS	Carbide	HSS	Carbide	HSS	Carbide	HSS	Carbide	HSS	Carbide	HSS	Carbide
Cast Iron	HB150-180		0.4	0.5	0.2	0.25	0.32	0.4	0.23	0.3	0.13	0.15	0.10	0.13
	HB180-220		0.32	0.4	0.18	0.2	0.25	0.32	0.18	0.25	0.1	0.13	0.08	0.1
	HB220-300		0.28	0.3	0.15	0.15	0.20	0.25	0.15	0.18	0.08	0.1	0.08	0.08
Malleable cast iron, Cast iron			0.3	0.35	0.15	0.18	0.25	0.28	0.18	0.2	0.1	0.13	0.08	0.1
Carbon steel	Cutting steel		0.3	0.4	0.15	0.2	0.25	0.32	0.18	0.18	0.23	0.13	0.08	0.1
	Soft steel, Steel		0.25	0.35	0.13	0.18	0.20	0.28	0.15	0.2	0.08	0.1	0.08	0.1
Alloy Steel	Annealing robust steel	HB180-220	0.20	0.35	0.10	0.18	0.18	0.28	0.13	020	0.08	0.1	0.05	0.1
		HB220-300	0.15	0.3	0.08	0.15	0.13	0.25	0.10	0.18	0.05	0.10	0.05	0.08
		HB300-400	0.10	0.25	0.05	0.13	0.08	0.2	0.08	0.15	0.05	0.08	0.03	0.08
	Stainless steel		0.15	0.25	0.08	0.13	0.13	0.20	0.10	0.15	0.05	0.08	0.05	0.08
Al-Mg Alloy			0.55	0.5	0.28	0.25	0.45	040	0.32	0.30	0.18	0.15	0.13	0.13
Brass, Bronze		speedy cutting	0.55	0.5	0.28	0.25	0.45	0.4	0.32	0.3	0.18	0.15	0.13	0.13
		ordinary	0.35	0.30	0.18	0.15	0.28	0.25	0.20	0.18	0.10	0.10	0.10	0.18
		hard	0.23	0.25	0.13	0.13	0.18	0.2	0.15	0.15	0.08	0.08	0.05	0.08
Coppper			0.30	030	0.15	0.15	0.25	0.23	0.18	0.18	0.10	0.10	0.08	0.08
Plastics			0.32	0.38	0.18	0.18	0.25	0.30	0.20	0.23	0.10	0.13	0.08	0.10