Used Elumatec Sbz 150 for sale (10,167)

Year of construction: 2006, condition: used, 3-axis machining center with automatic 8-station tool changer for aluminum or PVC profiles Max. travel stroke X-axis: 7200 mm Max. Travel of Y-axis: 400 mm Max. travel range Z-axis: 380 mm Control E 500 Iiodpfxozx D Sfj Am Deh Speed continuously adjustable up to 6,000 rpm handheld control unit minimum quantity spraying 3 angle heads Profile length measurement at the head Tensioner detection and automatic displacement 8 pneumatic material clamps Oscillating operation possible Photoelectric sensors

Year of construction: 2009, condition: used, 3-axis machining center with automatic tool change for aluminum or PVC profiles Max. travel X-axis: 3,850 mm Max. travel Y-axis: 350 mm Max. travel Z-axis: 280 mm Windows control with USB connections Speed continuously adjustable up to 22,000 RPM handheld control unit Ijdpoyqyaqjfx Am Dsih minimum quantity spraying Tool changer with 2 magazines (total 10 places plus angle head) tensioner detection and tensioner displacement 2 light barrier ranges and 2 material stops, enabling pendulum operation A total of 8 material clamps Spindle in good condition, spindle-insertion force: 12 kN Weight: approx. 2,000 kg

Year of construction: 2005, condition: used, CNC Machining Center Elumatec SBZ 122, year of manufacture 2005, designed for machining aluminum profiles for windows, curtain walls, and light metalwork. This is a robust and reliable industrial machine, highly regarded for its machining precision and operational continuity. Main features: Iiedjyg Ht Aspfx Am Deh - 3-axis CNC machining center - High-rigidity steel frame - Vertical spindle for milling, drilling, and complex operations - Worktable with pneumatic vices for stable and precise clamping - Long-travel longitudinal axis, ideal for processing profiles of considerable length - Protective enclosure with chip conveyor - Elumatec CNC control unit - Ideal for medium to high production and repetitive operations Applications: - Milling - Drilling - Slotting - End and face machining - Production of aluminum frames and special profiles Key data: - Manufacturer: Elumatec - Model: SBZ 122 - Year of manufacture: 2005 - Condition: Used Condition: - Machine in good overall condition - Coming from an industrial environment - Can be seen in operation by appointment Included equipment: - Complete workbench - Pneumatic clamping system - Control panel - Original covers and safety guards

Year of construction: 2007, operating hours: 4,100 h, condition: good (used), functionality: fully functional, The machine is not more needed for our production and therefore its for sale. The machine is in our ownership from 2007 and it is regularly maintained. Everything works normal. Dismantling and load on truck are in price. Some more informations: 5-axis profile machining centre Designed for flexible and efficient machining of aluminium Autonomous clamp positioning Max. working lenght: 9.300 mm 12 pneumatic clamps Tool magazine with 20 tools capacity and saw blade 500mm Ijdpowwtw Dsfx Am Deih Spindle working hours 4100h Additional tehnical specifications available on request

Condition: excellent (used), Year of construction: 2011, The machine in a very good condition. 7,6 meters long, 2 working places. Possible to give a warranty up to 6 month. Iiodoyia Ezspfx Am Dsh

Year of construction: 2010, condition: used, 4-axis machining center with 8-way tool changer for aluminum or PVC profiles Maximum machining length: 3,100 mm Iedsxvp Nkspfx Am Djih Y-axis travel: 850 mm Z-axis travel: 650 mm Swivel angle A-axis: 0° - 180° Max. speed 21,000 rpm Weight: approx. 3,000 kg Windows 7 operating system Minimum quantity spraying Clamp detection and automatic repositioning 6 pneumatic material clamps Loading is included in the price

Year of construction: 2007, condition: used, 3-axis machining center with automatic 8-station tool changer for aluminum or PVC profiles Max. Travel distance X-axis: 4200 mm Max. travel Y-axis: 480 mm Max. travel range Z-axis: 325 mm Control E 500 Speed continuously adjustable up to 6,000 rpm handheld control unit Iisdpfxjw Axfqj Am Dsh minimum quantity spraying Bidirectional angle head and a high-speed spindle Wrench measurement 8 pneumatic material clamps Light barrier Very good condition

Year of construction: 2008, condition: used, 3-axis machining center with automatic tool change for aluminum or PVC profiles Max. travel X-axis: 3,850 mm Max. travel Y-axis: 350 mm Max. travel Z-axis: 280 mm Control E 550 Speed continuously adjustable up to 24,000 rpm Handheld control unit Minimal量 sprühung tensioner detection and tensioner displacement Profile length measurement at the head Barcode scanner 5 pneumatic material clamps light barrier Additional material stop on the left for long profiles Spindle in like-new condition, spindle feeding force: 16 kN Iiedpfx Aozx Dz Tem Djh Weight: approx. 2,000 kg

Condition: excellent (used), Year of construction: 2022, operating hours: 52 h, functionality: fully functional, machine/vehicle number: 12200991016, rotational speed (min.): 24,000 rpm, overall weight: 1,635 kg, tool weight: 2,900 g, input voltage: 400 V, Do ekonomicznej i wydajnej obróbki profili z aluminium, tworzywa sztucznego i cienkościennych profili stalowych Iedpfxowgmyqj Am Dsih Wszystkie procesy obróbcze jak frezowanie, wiercenie i gwintowanie odbywają się na nieruchomym profilu, dzięki czemu powierzchnia profilu jest chroniona Lepsze wyniki pracy dzięki zastosowaniu inteligentnej techniki sterowania Szybkie pozycjonowanie zespołu obróbczego z prędkością sięgającą 60 m/min dzięki zastosowaniu dynamicznych serwonapędów Gwintowanie bez uchwytu kompensacyjnego Automatyczne rozpoznawanie zacisków i pozycjonowanie Automatyczny magazyn narzędzi z czterema półkami na narzędzia (bez narzędzi) Nowoczesne, 3-osiowe sterowanie Ergonomiczna praca dzięki zastosowaniu nowoczesnego łoża pochyłego Brak konieczności wykonywania ruchu referencyjnego osi dzięki zastosowaniu systemów opartych na enkoderach absolutnych Unikanie kolizji dzięki automatycznemu rozpoznawaniu zacisków i pozycjonowaniu Silnik frezarki Power-Torque z zamkniętym układem regulacji obrotów zapewnia krótki czas rozruchu i wyhamowania wrzeciona Certyfikowana, zintegrowane z napędem funkcje bezpieczeństwa Niskie zużycie prądu dzięki zastosowaniu inteligentnej techniki sterowania Większa efektywność energetyczna dzięki połączeniu napędów osi pomiędzy obwodami Awaryjne zasilanie elektryczne (UPS) System operacyjny Windows Panel PC 15,6", procesor i3, przyłącza USB oraz złącze sieciowe Łatwe i wygodne wprowadzanie programów za pomocą eluCam na panelu operatora również w czasie obróbki Zdalna konserwacja online Wyposażenie maszyny Chłodzone powietrzem wrzeciono frezu 8 kW, S1 Kabina do ochrony operatora Cztery poziome dociski pneumatyczne do mocowania materiału Ogranicznik materiału, po lewej stronie Uchwyt narzędzi HSK-F63 Smarowanie ilością minimalną Wysokowydajny płyn chłodzący Ręczny pulpit sterowniczy Szablon głębokości Opcje Narzędzia Uchwyty narzędzi Automatyczny magazyn narzędzi do maks. czterech narzędzi standardowych Automatyczny magazyn narzędzi do głowicy kątowej Obrotowa głowica kątowa HSK-F63 na dwa narzędzia Urządzenie chłodzące Green-line do szafy sterowniczej z obniżonym zużyciem energii Czytnik kodów kreskowych Kabina ochronna, opcjonalnie z zamknięciem dookoła Standardowo cztery zaciski. Możliwe jest rozszerzenie do ośmiu zacisków Prawy referencyjny ogranicznik materiału do przykładania elementów z obróbką nadmiarowych długości Dodatkowy ogranicznik do obróbki nadmiarowych długości po lewej stronie Obustronny pomiar długości Zacisk podwójny oraz dodatkowe akcesoria po złożeniu zapytania Panel PC 18,5", procesor i5 Panel PC 21,6", procesor i7 Uchwyt na notatki Osłona dźwiękochłonna Utylizacja wiórów z wykorzystaniem wanien na wióry

Condition: ready for operation (used), Year of construction: 2007, travel distance X-axis: 4,200 mm, travel distance Y-axis: 400 mm, travel distance Z-axis: 300 mm, overall weight: 9,000 kg, spindle speed (max.): 6,000 rpm, spindle motor power: 5,500 W, number of axes: 3, This 3-axis Elumatec SBZ 130 was manufactured in 2007. It features a maximum machining length of approximately 4200 mm and a robust Y-axis travel of 400 mm. The high-speed milling spindle operates at a maximum speed of 6000 rpm, supported by an 8-position turret head tool changer. If you are looking to get high-quality profile machining capabilities, consider the Elumatec SBZ 130 CNC profile machining centre we have for sale. Contact us for further details. • Control system: Ferrocontrol CNC • Max. machining length: approx. 4200 mm • Machining length with end machining: approx. 4080 mm • Spindle: • Type: High-speed milling spindle • Tool system: • Tool changer: Turret head Iijdpfoyt Hg Njx Am Dsh • Tool positions: 8

Year of construction: 2007, condition: ready for operation (used), Iedeyt E D Tjpfx Am Dsih

Year of construction: 2003, condition: used, 4-axis machining center with 8-way tool changer for aluminum or PVC profiles Max. Processing length: 6,400 mm Y-axis travel: 850 mm Z-axis travel: 650 mm Swivel angle A-axis: 0° - 180° Max. Speed 21,000 RPM Windows operating system minimum quantity spraying Tensioner detection and automatic displacement Chip conveyor belt in bed fume extraction Pendulum operation through two light barrier areas Loading is included in the price Weight: approx. 4,500 kg Isdpfxouwq S De Am Djih Very good condition

Year of construction: 2010, condition: ready for operation (used), functionality: fully functional, travel distance X-axis: 7,200 mm, travel distance Y-axis: 485 mm, travel distance Z-axis: 340 mm, spindle speed (max.): 6,000 rpm, machine/vehicle number: 1310031108, TECHNICAL DETAILS Travel range, X-axis: 7,200 mm Travel range, Y-axis: 485 mm Travel range, Z-axis: 340 mm Rapid traverse rate, all axes: max. 60 m/min Spindle speed: max. 6,000 rpm Spindle power: 5.5 kW Tool changer: Turret head Tool positions: 8 Iiodpfxszxngys Am Dsh MACHINE DETAILS Compressed air supply: 7 bar Compressed air consumption: approx. 100 l/min (with spray device) Electrical connection: 400 V, 3 ~, 50 Hz EQUIPMENT Turret tool changer with 8 tool positions

Year of construction: 2022, operating hours: 141 h, condition: ready for operation (used), functionality: fully functional, travel distance X-axis: 4,176 mm, travel distance Y-axis: 1,040 mm, travel distance Z-axis: 540 mm, milling spindle speed (max.): 20,000 rpm, saw blade diameter: 180 mm, machine/vehicle number: 122000029, Machine with only 141 operating hours! TECHNICAL DETAILS Travel range X-axis: 4,176 mm Travel range Y-axis: 1,040 mm Travel range Z-axis: 540 mm Traverse speed X-axis: max. 120 m/min Traverse speed Y-axis: max. 60 m/min Traverse speed Z-axis: max. 30 m/min Machining length without end-face machining: max. 3,851 mm Machining length with end-face machining: max. 3,525 mm Maximum bar diameter: 180 mm Tool storage locations in the automatic magazine: 12 Disc cutter diameter: 120 mm Saw blade diameter: 180 mm Iodpfxszgfvbs Am Deih Tool length: max. 150 mm Milling spindle speed: max. 20,000 rpm Milling spindle power: 7 kW S1 (water-cooled) Tool holder: HSK-F63 MACHINE DETAILS Voltage: 400 V Frequency: 50/60 Hz Power: 17.5 kW Current consumption: 25 A Maximum motor current consumption: 20 A Short-circuit resistance (Ik/SCCR): 5 kA Compressed air pressure: 7 bar Dimensions & Weight Dimensions (L x W x H): 7,643 x 2,171 x 3,000 mm Weight: 3,800 kg EQUIPMENT Automatic tool changer eluCam software Autonomous clamping jaw movement Premium clamping jaw with linear guide A-axis, infinitely adjustable from -120° to +120° C-axis, infinitely adjustable from -220° to +220° Note: Further technical details regarding the machine can be found in the attached document.

Year of construction: 2002, condition: used, 3-axis machining center with automatic 8-station tool changer for aluminum or PVC profiles Iijdpjzf I Ttjfx Am Djh Max. travel stroke X-axis: 6400 mm Max. Travel of Y-axis: 400 mm Max. travel range Z-axis: 380 mm Control E 500 Speed continuously adjustable up to 6,000 rpm handheld control unit minimum quantity spraying 2 angle heads and a high-speed spindle 8 pneumatic material clamps Oscillating operation possible Photoelectric sensors

Year of construction: 2006, condition: used, 3-axis machining center with automatic tool change for aluminum or PVC profiles Max. travel X-axis: 3,850 mm Max. travel Y-axis: 350 mm Max. travel Z-axis: 280 mm Control E 550 Stepless speed control up to 21,000 rpm Manual control device Minimal quantity spray Automatic tool changer with magazine (4 slots plus angle head) Spanner measurement and clamp displacement 4 pneumatic material clamps Light barrier Iedpsx Ecfkjfx Am Dsih Weight: approx. 2,000 kg

Condition: ready for operation (used), Year of construction: 2010, travel distance X-axis: 850 mm, travel distance Z-axis: 650 mm, spindle speed (max.): 24,000 rpm, spindle motor power: 11,000 W, number of axes: 4, This 4-axis Elumatec SBZ-140 was manufactured in 2010. It features a maximum profile length of 7600 mm and a Y-axis travel of 850 mm, making it suitable for machining aluminum and thin-walled steel profiles. The machine includes an air-cooled spindle with a maximum speed of 24,000 rpm and a tool magazine capacity of 8 positions for efficient operation. If you are looking to get high-quality machining capabilities, consider the Elumatec SBZ-140 vertical machining centre we have for sale. Contact us for further details. • Application: Machining of aluminum and thin-walled steel profiles • Operating system: Windows • Machining capabilities: Milling, drilling, tapping, end machining • Continuous machining range: 0°–180° • Working area: • Max. profile length with end machining: 7480 mm • Max. profile length without end machining: 7600 mm • Axis travels: • A-axis rotation: 0°–180° Iijdpfx Amezaq Eio Deh • A-axis programming increment: 0.1° • Axis speeds: • Y-axis: up to 60 m/min • Z-axis: up to 60 m/min • Spindle: Air-cooled • Tool magazine: 8 positions, co-moving for fast tool changes, expandable system • Machine features: Stationary profile machining, fast automatic tool changes, suitable for aluminum and thin-walled steel profiles, two machining zones (optional) • Pneumatic system: 7 bar required, approx. 180 l/min air consumption (with spray system) • Electrical data: 400 V / 3-phase / 50 Hz, main connection 63 A • Control panel: 15” color display, USB interface, LAN connection Additional equipment • Angle head set (0°, 90°, 180°, 270°) for end machining and double profiles • Pendulum mode / 2 working zones (optional configuration)

Year of construction: 2007, condition: used, 5-axis machining center with tool changer for aluminum or PVC profiles Max. machining length: 9,000 mm Travel Y-axis: 1150 mm Travel Z-axis: 715 mm A-axis swivel angle: 0° - 180° Angle C-axis: 0° - 180° Max. speed 24,000 rpm. Spindle power: 21 kW Tool changer with 13 standard and 7 special tools minimum quantity spraying Clamp detection and automatic shifting 12 pneumatic material clamps Pendulum operation through two light barrier areas Iiedpfx Amoxwydbe Deh Manual control console Loading is included in the price Weight: approx. 8,500 kg

Year of construction: 2007, condition: ready for operation (used), functionality: fully functional, travel distance X-axis: 4,200 mm, travel distance Y-axis: 485 mm, travel distance Z-axis: 340 mm, spindle speed (max.): 6,000 rpm, machine/vehicle number: 1300030760, TECHNICAL DETAILS Travel range, X-axis: 4,200 mm Travel range, Y-axis: 485 mm Travel range, Z-axis: 340 mm Max. speed, X-axis: approx. 60 m/min Max. speed, Y-axis: 30–60 m/min Max. speed, Z-axis: 30–60 m/min Isdpjzxngmjfx Am Dsih Max. spindle speed: 6,000 rpm Spindle power: 5.5 kW Tool changer: 8-position turret MACHINE DETAILS Compressed air supply: 7 bar Air consumption: approx. 100 l/min with spray device Power supply: 400 V, 3~, 50 Hz

Year of construction: 2010, condition: ready for operation (used), functionality: fully functional, working length: 7,600 mm, machine/vehicle number: 1400040505, number of axes: 4, TECHNICAL DETAILS Max. machining length with end face machining: 7,600 mm Max. machining length without end face machining: 7,720 mm EQUIPMENT 12 pneumatic collet chucks 2 work areas 4-axis profile machining center; stepless machining between -90° and +90° with each available tool Automatic clamping position adjustment with absolute measuring system Two separate machining zones for tandem operation 4-axis control 18.5" color monitor, USB ports, and network connection Windows operating system Iedozhuyfepfx Am Dsih EluCam software Automatic profile length measurement (on both sides) Barcode scanner The traversing tool magazine ensures short tool change times and thus optimal machining cycles; the magazine can be equipped with eight tools. 8x tool holders with collet chucks

Condition: ready for operation (used), Year of construction: 2013, operating hours: 1,280 h, functionality: fully functional, travel distance X-axis: 4,200 mm, travel distance Y-axis: 850 mm, travel distance Z-axis: 650 mm, spindle speed (max.): 24,000 rpm, swivel angle A-axis (max.): 180 °, TECHNICAL DETAILS Max. machining length without end face processing: 4,200 mm Max. machining length with end face processing: 4,080 mm Travel distances X-axis travel: 4,200 mm Y-axis travel: 850 mm Z-axis travel: 650 mm Traverse speeds X-axis traverse speed: 65 m/min Y-axis traverse speed: 60 m/min Z-axis traverse speed: 60 m/min Iiodpfx Amsw Svmie Djh Swivel range A-axis: 0° - 180° Positioning accuracy X-axis positioning accuracy: ± 0.1 mm Y-axis positioning accuracy: ± 0.1 mm Z-axis positioning accuracy: ± 0.1 mm A-axis positioning accuracy: ± 0.1° Max. spindle speed: 24,000 rpm Spindle rated power: 7 kW S1 Tool holder: HSK-F63 Max. cutter diameter: 80 mm Max. saw blade diameter: 200 mm MACHINE DETAILS Air consumption: approx. 180 l/min Machine weight: 4,200 kg Operating hours Spindle hours: 1,280 h Machine hours: 13,066 h

Year of construction: 2010, condition: not inspected (used), functionality: unexamined, travel distance X-axis: 8,500 mm, travel distance Y-axis: 480 mm, travel distance Z-axis: 325 mm, rotational speed (max.): 15,000 rpm, No minimum price – guaranteed sale to the highest bidder! TECHNICAL DETAILS X-axis travel: 8,500 mm Y-axis travel: 480 mm Z-axis travel: 325 mm Max. spindle speed: 15,000 rpm Spindle power: 5.5 kW Tool holder: BT 30 MACHINE DETAILS Tool changer: 8 positions Iiedpfxeypbmis Am Djh EQUIPMENT Tools

Year of construction: 2007, condition: ready for operation (used), functionality: fully functional, travel distance X-axis: 3,500 mm, travel distance Y-axis: 280 mm, travel distance Z-axis: 300 mm, spindle speed (max.): 21,000 rpm, working length: 3,750 mm, TECHNICAL DETAILS Machining length with bar support: 3,750 mm Machining length without bar support: 3,500 mm Travel range X-axis: 3,500 mm Travel range Y-axis: 280 mm Travel range Z-axis: 300 mm Positioning speed: 30 m/min Positioning accuracy: ±0.1 mm Spindle power: 6 kW Spindle speed: 21,000 rpm Spindle interface: HSK F63 Tool positions: 5 Max. tool diameter (manual): 200 mm Max. tool diameter (automatic): 92 mm Max. saw blade diameter: 500 mm MACHINE DETAILS Air consumption: approx. 50 l/cycle Compressed air requirement: > 7 bar Power supply: 400 V, 3-phase Note: The machine's operating hour counter is defective and cannot be read. The machine was only used in a single-shift operation. Iodpsznczkjfx Am Deih

Year of construction: 2005, condition: ready for operation (used), functionality: fully functional, power: 14 kW (19.03 HP), input current: 80 A, workpiece length (max.): 4,000 mm, machine/vehicle number: 6080008129, TECHNICAL DETAILS Maximum profile width: 130 mm Maximum profile height: 205 mm Maximum workpiece/profile length: 4,000 mm Processing capacity: 80 units MACHINE DETAILS Connection: 3 N/PE 400 V Frequency: 50 Hz Current: 80 A Power: 14 kW EQUIPMENT Powered, continuously adjustable gripper Lifting function for smooth feeding Iisdpfxszlnvue Am Doh Profile guidance on rollers Internal gripper to prevent damage to the profiles Integrated measuring sensors for workpiece length control Workpiece removal via outfeed table Portal design for high profile cross-sections Industrial PC with Windows operating system Barcode scanner

Condition: excellent (used), Year of construction: 2024, operating hours: 193 h, functionality: fully functional, travel distance X-axis: 7,200 mm, travel distance Y-axis: 480 mm, travel distance Z-axis: 340 mm, cutting width (max.): 335 mm, workpiece length (max.): 6,000 mm, milling spindle speed (max.): 6,000 rpm, section length (max.): 6,000 mm, TECHNICAL DETAILS - Profile Milling Machine Processing length: 7,200 mm Number of axes: 4 Control: eluCAM graphical, Windows XP user interface Workstations: 2 independently operating stations Turret tool changer: 8 tools, servo motor driven Tool holder: BT 30 Disc mill diameter: 180 mm Tool length: 150 mm (from point of attachment) Travel distances Travel X-axis: 7,200 mm (without end-face processing), 7,080 mm (with end-face processing) Travel Y-axis: 480 mm Travel Z-axis: 340 mm Rapid traverse X-axis: 60 m/min Rapid traverse Y-/Z-axis: 30 m/min Positioning accuracy: ±0.1 mm/m Spindle Milling spindle speed: 1 to 6,000 rpm Milling spindle power: 6.0 kW Supply Air connection: min. 7 bar Air consumption: 100 l/min Electric connection: 400 V, 3~, 50 Hz, 35 A EQUIPMENT two independent workstations with light barrier and camera system Non-swiveling inclined milling head for 2 tools, Er20A, up to 18,000 rpm Inclined milling head swiveling 4 × 90°, Er20, up to 22,000 rpm Inclined milling head non-swiveling for steel, Er20A, 1,554 rpm Fixed saw head i=1:1, for D=300 mm saw blade, suitable for 90° cross cuts Carbide saw blade Z=100, D=300 mm, cutting width 3.2 mm Tool holder i=1:3.86 for 18,000 min⁻¹, ER25 Cooling/lubricating unit for steel processing Disc milling holder BT30, D=16 mm Disc cutter D=92 × 6 mm, Z=14, D=16 mm, carbide teeth TECHNICAL DETAILS - Double Mitre Saw Max. cutting length: 6,000 mm Min. cutting length at 90°: 335 mm Min. cutting length at 45°: 335 mm Saw blade diameter: 420 mm Cutting angle (rotation): pneumatically adjustable 90° and 45° inside, intermediate angles and 22.5° acute manually adjustable with digital display Cutting angle (tilt): pneumatically adjustable 90° and 45° inside Saw direction: saw blades move from bottom to top Control Control type: E580/1 Length adjustment: automatic with positioning control Saw blade tilt: pneumatically automatic between 90° and 45° Positioning accuracy: ±0.1 mm/m Positioning: pneumatic locking Operating system: Windows Isdpfx Amswprmzs Deih Saw unit Speed: 2,800 rpm Power per motor: 4,000 W (5.5 HP) Saw blade cooling: available Air consumption per cycle without cooling: 40 l Air consumption per cycle with cooling: 64 l Supply Electric connection: 230/400 V, 3-phase, 50 Hz Air connection: 7 bar Dimensions and Weight Length: 7,550 mm Width: 1,600 mm Height: 1,450 mm Weight: 1,750 kg EQUIPMENT Automatically closing protective covers Electronic positioning of the heads with +/- 0.1 mm/m accuracy Digital angle display for manually adjustable special angles Pneumatically adjustable saw blade rotational and tilt angles Operation via Windows control with 8.4" display and handwheel Cooling system for saw blades included Saw unit with bottom feed for optimal cutting force