The Bernardo KBM 50 fixed column drill is the upper-medium model in the KBM range, featuring a 4 kW motor and MT 5 taper, with a drilling capacity in steel up to Ø 50 mm and threading up to M42 with automatic reversal. Technical specifications: MT 5 Morse taper attachment, 9 spindle speeds 45-850 rpm (in steps), automatic spindle feed with 9 ranges 0.056-1.8 mm/rev, 4.0 kW motor with 350 Nm torque, 16,000 N feed force. 560 × 480 mm cast iron table with 18 mm T-slots, 315 mm table lift, 335 mm spindle-column distance, max 720 mm spindle-table distance. Cast iron structure, weight 1,250 kg, machine dimensions 750 × 1,150 × 2,520 mm. Distributed in Italy by Krollit as an official Bernardo distributor since 2007.
-
Steel drilling capacity: Ø 50 mm
-
Threading capacity: M42 with automatic reversal
-
Morse taper attachment: MT 5
-
Spindle speed: 9 speeds 45-850 rpm
-
Spindle torque: 350 Nm
-
Feed force: 16,000 N
-
Spindle stroke: 250 mm
-
Cast iron table: 560 × 480 mm with 18 mm T-slots
-
Table lift: 315 mm
-
Motor: 4.0 kW 400V three-phase
-
Weight: 1,250 kg
Who uses the KBM 50 and for what
The Bernardo KBM 50 is a medium-heavy duty fixed column drill for industrial workshops with high-capacity mechanical production. Drilling capacity Ø 50 mm and threading up to M42: sized for medium-to-large workpieces (over 200 × 200 mm), with a 4.0 kW motor and 350 Nm torque, more than double that of the KBM 25/32 models. The 16,000 N feed force allows through-drilling on high-strength alloy steels (HSS tool steel, 42CrMo4, 30NiCrMo12) and tough materials. 560 × 480 mm cast iron table with 18 mm T-slots: larger dimensions than light models for supporting large workpieces. The MT 4 attachment supports tools up to Ø 50 mm: for drilling diameters larger than the Morse taper, this model is not correctly sized, the KBM 50 (MT 5) version is required. Typical application sectors: mechanical industry with production of medium-heavy mechanical components, industrial maintenance workshops for engine and transmission repair, metal structural work with heavy structures for construction and infrastructure, agricultural industry for construction and maintenance of agricultural machinery.
Its place in the Bernardo range
The Bernardo drill range is organized into 3 main categories: bench drills (DMT 20, BM, TB) for craft workshops with occasional use; fixed column drills (KBM 25/32/40/50/63/80) for industrial workshops with high-capacity mechanical production; gear drills (GB 30 TV) for precision workshops requiring superior concentricity. The KBM 40 and KBM 50 are the medium models in the KBM range, sharing a frame (560×480 mm table, 1,250 kg weight) and MT 5 spindle taper. Differences: the KBM 40 has Ø 40 mm drilling with a 3.0 kW motor and speeds of 31.5-1,400 rpm; the KBM 50 has Ø 50 mm drilling with a 4.0 kW motor and speeds of 45-850 rpm (lower range for higher torque on large tools). For workshops with typical tools Ø 25-40 mm, the KBM 40 is the correct choice; for workshops with tools Ø 40-50 mm, the KBM 50 is sized with a superior motor. For higher capacities (Ø 63-80 mm), the KBM 63/80 models are correctly sized (heavy category with 5.5 kW motor and 800 Nm torque).
Krollit logistics and support
Bernardo shipping in 5-9 working days (7 days to Southern Italy). Due to its high weight, a crane or heavy pallet truck is required for unloading from the transport vehicle and installation. Internal workshop handling with a forklift or manual pallet truck (at least 1,500 kg capacity). HSS drill bits in MT tapers, milling chucks, threading devices, LED lamps, coolant pumps, original Bernardo spare parts (belts, gears, gaskets, motors) available from stock with 3-5 working days shipping. Customer support available in Italian.
Who is the KBM 50 for
| Profile |
Compatibility |
Reason |
| Hobbyist or workshop with occasional use |
Not recommended |
1,250 kg industrial machine requiring a 400V three-phase line. For occasional use, the DMT 20 bench drills or BM/TB column drills are correctly sized. |
| Mechanical industry with medium-heavy parts |
Recommended |
560×480 mm table for supporting large workpieces, 4.0 kW motor with 350 Nm torque for through-drilling on alloy steels. 16,000 N feed force allows for heavy-duty machining. |
| Metal structural work for welded structures |
Recommended |
315 mm table lift allows adaptation to different workpiece heights. Threading with automatic reversal for threaded holes on structures in the workshop. |
Not recommended for: workshops without an adequate 400V industrial three-phase line; environments without space for machine dimensions (750 × 1,150 × 2,520 mm); precision drilling with superior concentricity (for concentricity ≤ 0.02 mm, the GB 30 TV or CNC drills are correctly sized); occasional hobby use (the machine is oversized, consider DMT 20 or BM/TB drills from the bench drill range).
Working capacity
| Specification |
Value |
| Steel drilling capacity |
Ø 50 mm |
| Max. threading capacity |
M42 |
| Morse taper attachment |
MT 5 |
Speeds and feeds
| Specification |
Value |
| Spindle speed |
9 speeds 45-850 rpm |
| Spindle torque |
350 Nm |
| Spindle stroke |
250 mm |
| Drill head travel |
195 mm |
| Spindle feed |
9 ranges 0.056-1.8 mm/rev |
| Feed force |
16,000 N |
Table and working dimensions
| Specification |
Value |
| Table dimensions |
560 × 480 mm |
| T-slots |
18 mm |
| Table lift |
315 mm |
| Spindle-column distance |
335 mm |
| Max. spindle-table distance |
720 mm |
Motor and power supply
| Specification |
Value |
| Motor power |
4.0 kW |
| Voltage |
400V three-phase / 50 Hz |
Dimensions and weight
| Specification |
Value |
| Machine dimensions (L × W × H) |
750 × 1,150 × 2,520 mm |
| Weight |
1,250 kg |
Compliance
| Specification |
Value |
| Marking |
CE |
| Directive |
Machinery Directive 2006/42/EC |
Standard equipment
- Bernardo KBM 50 drill
- Integrated cooling device
- Threading device with automatic reversal
- Right/left rotation (R/L)
- Integrated LED work light
- Morse taper sleeve
- Height-adjustable CE compliant protection
- Service tool set
- User manual in Italian
Frequently asked questions
What is the difference between MT 5 taper and other tapers?
The MT 5 Morse taper is sized for tools up to Ø 50 mm. For tools with larger diameters, a larger Morse taper is required (MT 4 for Ø 32-40 mm, MT 5 for Ø 40-63 mm, MT 6 for Ø 63-80 mm).
The Morse taper is an international standard defining the conical coupling between the spindle and the tool: the taper is designed for self-clamping during rotation. HSS drill bits, milling cutters, reamers, and reduced taper sleeves are available in all MT tapers. For B16 or B18 tools (cylindrical with screw clamping), a drill chuck with the machine's MT shank is required: professional self-tightening chucks are recommended for quick and safe tool changes.
How does the automatic spindle feed work?
The automatic feed lowers the spindle at a constant, adjustable speed depending on the material, eliminating the operator's physical effort on the manual lever. The 9 feed ranges (0.056-1.8 mm/rev) cover different materials: 0.056-0.1 mm/rev for hard steels, 0.1-0.3 mm/rev for alloy steels, 0.3-0.7 mm/rev for mild steels, 0.7-1.8 mm/rev for aluminum and light alloys.
Correct feed is crucial for: drill bit life (excessive feed causes breakage), hole quality (reduced feed causes slow machining and high burr), machine productivity (optimal feed significantly reduces drilling times). For serial production, automatic feed allows for multiple identical holes without manual intervention: a decisive feature for productivity.
Does M42 threading require a specific device?
Yes, and it is included in the standard equipment. The threading device with automatic reversal allows for M42 threading without the need for manual spindle stops: the direction of rotation automatically reverses when the set depth is reached.
Standard threading procedure: mount the tap in the MT tap holder sleeve, adjust the depth stop, position the workpiece on the table with threading lubricating oil. The operator starts the machine, the spindle rotates forward cutting the thread, and when the depth is reached, the direction automatically reverses, retracting the tap. Specific oil for threading on steel (e.g., CutCool, Tapping Fluid) is recommended for thread quality and tap life.
Can I perform precision drilling with this drill?
For standard precision (concentricity 0.05-0.1 mm), yes. For superior precision (concentricity ≤ 0.02 mm), gear drills (GB 30 TV) or CNC drills with precision spindles are correctly sized.
KBM fixed column drills have belt drive with typical industrial standard concentricity. For higher precision applications (precision reaming, drilling for H7 fits), the GB 30 TV with hardened and ground gear drive offers concentricity ≤ 0.02 mm. For extremely precise industrial applications (concentricity below 0.01 mm), dedicated boring machines or CNC machining centers are required.
What electrical power supply is needed for this machine?
400V three-phase line with adequate cable cross-section for the 4.0 kW motor: typically 4 mm² up to 30 meters, 6 mm² over 30 meters. Dedicated 20A circuit breaker.
For workshops without a three-phase line, electrical adaptation is necessary (typical cost €500-1,500 for a new three-phase meter + wiring + circuit breaker). For workshops with a three-phase line but undersized cables, the cost is limited to dedicated wiring (€200-500). Pre-purchase verification is recommended: contact a qualified electrician to check the availability of power on the existing meter and the current cable cross-sections.
