Ultra-precision machining
Ultraprecision-machining (UP machining) not only defines the dimensional and form accuracy of a machined part, but also its surface finish. While some companies focus on achieving high precision and others on superior surface finishes, combining both often leads to unachievable challenges, shaping the definition of “ultra-precision machining.”
Although no strict values exist, a machine system can be considered ultra-precise when repeatable positioning accuracies in multi-axis operations and spindle errors fall below 50 nm . These systems are inherently complex and demand highly skilled operators.
With the constant push for efficiency and automation, Levicron’s spindle solutions allow ultra-precision machining combined with automated manufacturing like you know from CNC-machining.
Levicron’s Mission
“Making Ultra-Precision Machine Tools
more productive”
Requirements on ultra-precision machining systems
Demanded properties of ultra-precision components
Automated ultra-precision manufacturing with spindle solutions from Levicron
Diamond turning is a cutting process that uses a defined, stationary cutting edge, typically made of monocrystalline diamond (MCD) or polycrystalline diamond (PCD).
This production process is required to machine optical-quality surfaces and ultra-precise parts made from metals or non-metals. The part shape often is rotationally symmetric, but using technologies like FTS (Fast
Tool Servos) also allow the machining of non-symmetrical parts to a certain degree.
A process in which the tool and the workpiece rotate is called turn-milling.
Milling is a machining process that uses a rotating cutting tool with a defined cutting edge, where the cutting edge(s) is typically made from MCD *) or PCD **).
It can be performed as a single-cutting-edge process (fly-cutting) or as a multi-cutting-edge process.
Grinding is a machining process that uses an undefined cutting edge (abrasive grain). The abrasive materials are typically made from diamond or CBN ***) and are bound in a ceramic, plastic, or metal matrix.
Grinding tools can be either dressable or non-dressable. For non-dressable grinding tools, low tool run-outs and synchronous spindle errors are crucial. In the case of dressable grinding tools, also the asynchronous spindle errors affect shape and surface quality of the machined part.
The most precise process with the longest machining time is polish-grinding.
Other processes: EDM (Electro Discharge Machining) and laser ablation.
*) MCD = Monocrystalline diamond **) PKD= Polycrystalline diamond ; ***) Cubic boron nitride
Our recommendations for your ultra-precision results
ASD-Px
The most versatile and robus work-holding spindle solution with many housing and mounting options, offering speeds of up to 12,000 rpm and spindle errors under 12 nm.
Our ASD-Px, designed as spcifically robust high-load work-holding spindle (also: work-head) featuring in-house developed iron-less BLDC motors and our patented aerostatic bearing system, has established itself as a benchmark for ultra-precision work-holding.
Ready for your ultra-precision turning or positioning tasks.
Over a period of five years, our ASD-Px exhibits the following average spindle errors according to DIN ISO 230-7:
- Synchronous: Radial 6.5 nm, Axial 5.3 nm
- Asynchronous: Radial 2.8 nm, Axial 1.4 nm
U/ASD-Cx/ ASD-CLT
Contact lens turning with automatic, pneumatically actuated precision collet for 1/2″ block pieces.
While other providers of spindle solution for contact lens turning just fall back on available conventional or high-speed spindle designs, we have modified our ultra-precision tool spindle ASD-Cx with spindle errors of less than 30 nm to be used for contact lens turning.
This enables users to achieve lens qualities with surface roughness of under 2 nm Ra.
U/ASD-H25(A)
The reference for mold machining for optical components with automatic (spring-less) HSK-E 25 clamping.
Our tool motor spindle U/ASD-H25(A) focus on on dynamic and thermal stability, stiffness and lowest spindle errors (DIN ISO230-7: < 30 nm), making it the ideal choice to machine mold and dies for optical components and direct optics using milling, mill-turning or grinding.
These outstanding features are complemented by a fast, automatic and spring-less tool clamping system for HSK-E25 (DIN69893), especially developed for ultra-precision machining.
Selected references
