Special machines and contract work for ultra-precision honing and grinding of the smallest bores and outside diameters in hard materials
Schläfli Engineering AG
Büren an der Aare (CH)New on Amplifa
About us
Schläfli Engineering AG, based in Büren an der Aare in the canton of Bern, develops and produces ultra-precision machines for finishing small bores and outside diameters of components with a centric bore. The portfolio comprises wire honing machines (acuwire-S/-L/-H) for bores of 0.04 to 2.0 mm, the wire-guided centerless grinding machine acugrind-C for outside diameters of 0.5 to 12 mm, as well as needle-controlled machines for drilling and for grinding/polishing concave and convex shapes. Materials machined include extremely hard substances such as ruby, sapphire, tungsten carbide and technical ceramics (zirconium oxide), as well as steel and stainless steel. The machines are used worldwide, including in the watchmaking, textile, automotive, toolmaking and medical industries, for example for dies, nozzles, bushings, bearings, pinions or ferrules. In addition to machine building, the company offers contract work (honing and grinding in-house), machine overhauls, maintenance, spare parts and rental machines.
- Site
- Büren an der Aare
- Processes
- Wire honing of small cylindrical bores, ID 0.05 – 2.00 mm, series production, Wire honing of bores 0.10 – 0.80 mm (acuwire-S), Wire honing of bores 0.4 – 2.00 mm (acuwire-L), Manual wire honing for maximum precision (acuwire-H), also for small and medium series, Wire-guided/centerless grinding of outside diameters with high concentricity (ID to OD), Precision drilling in hard materials (sapphire, ruby, ceramics, tungsten carbide), e.g. bearings, Grinding/polishing of concave and convex shapes (watch jewels, industrial balls), Contract work: honing or grinding of customer workpieces in-house (job shop)
- Materials
- Ruby, Sapphire, Carbide (Tungsten carbide), Technical ceramics (Zirconium oxide), Steel, Stainless steel (medical tubes), Tungsten carbide (Carbide), Technical ceramics (zirconium oxide)
- Certificates
- Endurance tests after overhaul
- Founded
- Early 1960
- Industries
- Watchmaking industry, Textile industry, Automotive, Toolmaking, Medical technology, Microtechnology
- 01
Machine development and design
- 02
Machine building (honing, grinding, drilling)
- 03
Contract work: honing and grinding of customer workpieces
- 04
Accessories: honing and guide wire, diamond suspension, casting systems, gauge
- 05
Service: support, maintenance, spare parts, overhaul, rental machines
Materials & Processes
Ruby
Material for bearing jewels and machining examples in wire honing and centerless grinding.
Sapphire
Hard material for bearings, watch glass lenses and probe balls, drillable and grindable on the BA-2 and CMU.
Tungsten carbide (Carbide)
Extremely hard material for bushings, guides and tubes with tolerances down to ±0.001 mm.
Technical ceramics (zirconium oxide)
Ceramic tubes and connectors, wire-honeable and grindable in series production.
Steel
Machinable on all honing and grinding machines, from very hard to relatively soft.
Stainless steel
Medical tubes as typical workpieces for the acugrind-C.
Locations
Büren an der Aare
CHHeadquarters, production, showroom
- Part weight / size
- Bores 0.04–2.0 mm · Outside diameters 0.5–12 mm
- Lot size
- Single parts to series; acuwire-H for small and medium series as well as
- Materials
- Ruby, sapphire, tungsten carbide, zirconium oxide, steel, stainless steel
- acuwire-S (wire honing machine, bores 0.04–0.80 mm)
- acuwire-L (wire honing machine, bores 0.4–2.0 mm)
- acuwire-H (manual wire honing machine)
- acugrind-C (wire-guided centerless grinding machine)
- BA-2 (drilling machine, 3 production units)
- CMU (grinding/polishing machine concave/convex)
- FineHone-250 / FineHone-600 / Polish Master-4000 (rental machines)
Industries
Processes & technical limits
| Processes | Tolerance | Max. part | Weight | Lot size | Materials |
|---|---|---|---|---|---|
| Wire honing of small cylindrical bores, ID 0.05 – 2.00 mm, series productionMachining | e.g. ±0.001 mm; 0/+0.002 mm; 0/+0.004 mm (sample data) | 200 mm (maximum workpiece/mandrel | – | – | Ruby, Carbide (tungsten carbide), Technical ceramics (zirconium oxide), Steel |
| Wire honing of bores 0.10 – 0.80 mm (acuwire-S)Machining | ±0.001 mm; 0/+0.004 mm (sample data) | 200 mm | – | – | Ruby, Carbide, Technical ceramics, Steel, Zirconium oxide |
| Wire honing of bores 0.4 – 2.00 mm (acuwire-L)Machining | ±0.001 mm; 0/+0.002 mm (sample data) | 200 mm (option: 280 mm) | – | – | Ruby, Carbide, Technical ceramics, Steel, Zirconium oxide |
| Manual wire honing for maximum precision (acuwire-H), also for small and medium seriesMachining | – | – | – | small to medium lot sizes | hard materials (ruby, carbide, technical ceramics, steel) |
| Wire-guided/centerless grinding of outside diameters with high concentricity (ID to OD)Machining | 0/+0.0127 mm; ±0.002 mm (sample data) | 1000 mm (workpiece/chain length) | – | – | Carbide, Ruby, Sapphire, Ceramics (zirconium oxide), Stainless steel (medical tubes), Permanent magnets |
| Precision drilling in hard materials (sapphire, ruby, ceramics, tungsten carbide), e.g. bearingsMachining | – | – | – | – | Sapphire, Ruby, Ceramics, Tungsten carbide |
| Grinding/polishing of concave and convex shapes (watch jewels, industrial balls)Machining | – | – | – | – | Sapphire, Ruby, Ceramics, Tungsten carbide |
| Contract work: honing or grinding of customer workpieces in-house (job shop)Machining | – | – | – | – | – |
| Rental machines: honing IDs 0.04 – 0.25 mm / max. OD 6.0 mm (FineHone-250)Machining | – | max OD 6.0 mm | – | – | – |
| Rental machines: honing IDs 0.25 – 0.60 mm / max. OD 8.0 mm (FineHone-600)Machining | – | max OD 8.0 mm | – | – | – |
| Brush polishing (Brush polishing machine Polish Master-4000)Surface | – | – | – | – | – |
| Machine overhaul and maintenance (Machine revision)Engineering | – | – | – | – | – |
9 Anlagen & Maschinen
| Machine | Manufacturer / model | Quantity | Working area | Year built | Site |
|---|---|---|---|---|---|
| Wire honing machine | Schläfli acuwire-S | – | Bores 0.04 – 0.800 mm, part OD up to 10 mm, max. length 200 mm, spindle 100-3000 min-1 | – | Büren an der Aare, Switzerland |
| Wire honing machine | Schläfli acuwire-L | – | Bores 0.4 – 2.0 mm, part OD up to 10 mm, max. length 200 mm (option 280 mm), spindle 500-4000 min-1 | – | Büren an der Aare, Switzerland |
| Manual wire honing machine (Single/Twin) | Schläfli acuwire-H | – | Bores up to 2 mm, wire length 0 – 3000 mm | – | Büren an der Aare, Switzerland |
| Wire-guided centerless grinding machine | Schläfli acugrind-C | – | Part OD 0.500 – 12.000 mm, bore (guide wire) 0.100 – 6.000 mm, max. chain length 1000 mm | – | Büren an der Aare, Switzerland |
| Drilling machine (3 independent production units, cam-controlled) | Schläfli BA-2 | – | – | – | Büren an der Aare, Switzerland |
| Automatic grinding/polishing machine for concave/convex shapes (up to 3 production units) | Schläfli CMU | – | – | – | Büren an der Aare, Switzerland |
| Honing machine (rental machine) | Schläfli FineHone-250 | – | IDs 0.04 – 0.25 mm / max OD 6.0 mm | – | Büren an der Aare, Switzerland |
| Honing machine (rental machine) | Schläfli FineHone-600 | – | IDs 0.25 – 0.60 mm / max OD 8.0 mm | – | Büren an der Aare, Switzerland |
| Brush polishing machine (rental machine) | Schläfli Polish Master-4000 | – | – | – | Büren an der Aare, Switzerland |
Additional services
Quality
The machines achieve diameter tolerances down to ±0.001 mm as well as defined roundness, cylindricity and concentricity values; for inspection, tungsten carbide gauge pins are offered. After every overhaul, each machine undergoes an endurance test with the precision of a new machine.
| Evidence | Büren an der Aare |
|---|---|
| Endurance tests after overhaul |
History
- ca. 1960
Founded in Büren an der Aare as a supplier to the watchmaking industry; the founder developed his own machines for machining ruby bearings, which soon spread throughout the entire watchmaking trade.
- 1990
Taken over by a son of the original owner and converted into a private stock corporation; entry into the world market.
- 2015
A new generation takes over the management of the company.
- 2016
Market launch of the wire-guided centerless grinding machine acugrind-C (March); presentation at GrindTec in Augsburg and at EPHJ in Geneva; website relaunch.
- 2017
Market launch of the manual honing machine acuwire-H (February); presentation at EPHJ.
- 2019
Participation in EPHJ in Geneva (booth R03, 18–21 June).