The Cutwel range of spindle nose tooling for CNC machining centres, manual milling machines, radial arm drills and multitasking mill-turn machines includes all main tapers: BT MAS (BT30, BT40, BT50), DIN 69871 (SK40, SK50), DIN 2080 (ISO30, ISO40), Erikson Quick Change (QC30, QC40), Morse Taper, PSC (Polygon taper, compatible with Capto), HSK type A, E & F (HSK32, HSK40, HSK50, HSK63, HSK80 & HSK 100), Dual contact / face and taper contact (DBT30, DBT40, DBT50, DSK40, DSK50), R8 (Bridgeport) and straight shank holders.
Tooling is available in a range of balancing ratings from 8,000RPM G6.3 up to 40,000RPM G2.5 as standard, with holders ranging from economical low-cost ranges to ultra-high precision and high torque holders for performance machining. Supplied by manufacturers including YG-1, Bilz, WTE and Dine.
Cutwel holds stock of a vast range of tool holder types including ER collet chucks, side-lock arbors / end mill holders, heat shrink chucks and extensions, SK slim chucks, anti-vibration face mill arbors, hydraulic power chucks, morse taper chucks, synchro or tension and compression tap chucks, basic or CNC drill chucks and taper to taper adapters. All holders are supported by a vast range of accessories including ER collets, SK collets, hydraulic chuck sleeves, wrenches and pull studs.
BT MAS Tool Holders
JIS (MAS 403) / JIS B 6339 (BT30/BT40/BT50) holders feature steep taper designs of 8° 17'50'' +4'' and automatic tool change flange. Holders are located in the machine spindle using a pull stud which screws into the base of the holder. BT MAS is a Japanese standard and is typically found on Korean, Taiwanese, Japanese and some American machining centres; is the most popular taper used in the UK. BT machining centres for around 70% of new machines spindles in the UK.
Machine tools using BT spindles are typically supplied with maximum spindle speeds of 12,000RPM. However, some machines are capable of up to 15,000-25,000RPM. BT MAS holders are suitable for both light or heavy machining and have through coolant supplied either through the end of the tool (AD) or through the flange (AD/B).
DIN 69871 Tool Holders
DIN ISO 7388-1 (formerly DIN 69871) SK30, SK40 & SK50 holders feature steep taper designs of 8° 17'50'' +4'' and automatic tool change flange. Holders are located in the machine spindle using a pull stud which screws into the base of the holder. They are easy to tell apart from BT MAS holders due to the V-cut out on the tool change flange and thinner flange thickness. DIN 69871 holders are typically found on German, Italian and some American machine tools.
Machining centres using DIN 69871 spindles are typically supplied with maximum spindle speeds of 12,000RPM. However, some machines are capable of up to 15,000-25,000RPM. DIN 69871 holders are suitable for both light or heavy machining and have through coolant either supplied through the end of the tool (AD) or through the flange (AD/B).
HSK DIN 69893 Tool Holders
HSK (hollow shank) tool holders are available in different standards: HSK-A, HSK-C, HSK-E & HSK-F. The main benefit of HSK holders is that they offer far superior axial rigidity compared to BT MAS or DIN 69871 holders, which is due to the face and taper contact in the machine spindle. They are also often chosen for machine tools with higher spindle speeds as they are more suited to high-speed machining. The HSK taper is available in a range of sizes including: HSK25, HSK32, HSK40, HSK50, HSK80, HSK100 & HSK125, with HSK63 being the most common size in the UK (which is comparable to BT40 or SK40 in size).
HSK-A holders are designed for metal milling machining centres and offer the greatest torque due to their drive slots. Coolant is fed through the tool using a HSK coolant adapter. HSK-A toolholders feature slots and keyways in the flange for high-speed automatic tool changes. HSK-C toolholders are largely the same as HSK-A but do not feature a keyway or slot on the flange as they are designed for manual tool changes. HSK-E tool holders are designed for higher speed machining than HSK-A and have all features that cause unbalance removed. HSK-E holders are typically used for wood, plastic or aluminium CNC routers and are friction driven. They feature a grooved flange for automatic tool change and use a HSK coolant adapter for through spindle coolant. Due to their low torque transfer, HSK-E holders are not suitable for heavy metal machining. HSK-F holders are also designed for very high-speed machining and have the same features as HSK-E. However, they feature a larger diameter flange.
PSC ISO 26623 Tool Holders
PSC holders (colloquially referred to as ‘Capto’) is a standard designed and developed by Sandvik Coromant, which is now more widely manufactured under standard ISO 26623. The spindle interface is an extremely innovative design with maximum precision and torque transmission. It is mainly used in multi-tasking machines (turn-mill machining centres). The shank features a polygon-shaped taper with flange surface contact which creates exceptionally high torque transfer and axial rigidity. PSC holders are available for milling, drilling or as adapters for turning/boring tools as well as being available as monoblock turning, drilling, grooving, threading and boring tools.
Dual Contact Holders
Also known as face and taper contact holders, dual contact holders are often colloquially referred to as ‘Big Plus’ holders after the brand that originally developed the standard. They are available in BT MAS or DIN 69871 standard but with the additional benefit of full-face contact in the spindle. This prevents tool holder deflection during heavy milling and increases rigidity, improves tool life and surface roughness.
DIN 2080 Tool Holders
DIN 2080 holders are supplied in sizes ISO30, ISO40 & ISO50. They are used in conventional/manual milling machines or semi-CNC machines without automatic tool change. Holders have an integral thread in the base (M12, M16 or M24 depending on taper size) which screws into the machine draw bar. BT MAS or DIN 68971 tool holders can be used on DIN 2080 machines with the use of a special adapter pull stud. However, these cannot be used on machines with an automatic draw bar.
R8 holders are used on manual milling machines. The R8 standard was developed by Bridgeport for their own manual mills. R8 spindles are now used widely by other machine tool manufacturers.
What is the best tool holder for my machine or application?
This depends on what your objectives are. ER collet chucks are exceptionally versatile, good value and offer perfectly good performance in general machining. However, if you are seeking the best cycle times, better surface finish or improved tool life, you may get better value by investing in higher performance tool holders such as hydraulic chucks or shrink chucks.
What is run-out on a tool holder and why is it important?
Run-out if the measurement of inaccuracy in the rotation of a tool holder or cutting tool to the centre of the axis. In simple terms, the lower the run-out, the more accurate a holder is. Run-out on tool holders is typically measured at 3 x the diameter tool length. The higher the run-out, the greater vibration will be and the higher the risk of tool failure. High run-out can also cause tools to cut oversize or wonky. Run-out disproportionately affects small diameter tools or long reach tools.
Most basic spindle tooling holders will offer <10 microns run-out at 3xD tool length. This is perfectly adequate for many applications. If reach is extended to 6xD or 10xD, however, the run-out will increase along with the reach and performance/tool life decreases. Holders with <3 microns run-out offer much higher precision, better tool life, faster cutting speeds and better surface finish. This may not be required for lower cost tools.