High Performance Dowel Drill Bits 57mm Blind Hole Drilling Bit For Cutting Machines

Need a dowel bit that drills clean blind holes on a CNC drilling head and still fits a left-hand spindle? The 40221240 blind hole drilling bit covers that in one stock item: 5 mm to 15 mm in nine diameters, 57 mm and 70 mm overall lengths, and a 10 mm cylindrical shank that fits CNC drilling machines, cutting machines, machining centres and multi-head drilling machines. Carbide-tipped brad point with spur for a clean rim, right-hand and left-hand rotation, MOQ 50 PCS, other sizes to drawing.

A cabinet shop drills the same dowel hole thousands of times a week, and three things keep costing it money: a bit that walks off the mark on melamine, an order of bits that only fits right-hand spindles, and a re-order that arrives in the wrong length. The 40221240 blind hole drilling bit is specified to remove all three.

The 40221240 bit is a carbide-tipped dowel and blind hole bit for woodworking drilling heads. Nine diameters run from 5 mm to 15 mm, in two overall lengths of 57 mm and 70 mm, all on a 10 mm cylindrical shank. Right-hand and left-hand rotation are both supplied, so a counter-rotating spindle pair is filled from one stock line.

The point is a brad point with a spur, so the rim scores the veneer before the flutes lift the chip, and the entry stays clean on melamine-faced board. Helical flutes carry dust out of the hole, and the carbide tip keeps the cutting edge on the outside diameter, which is where a blind hole actually needs it.

The 10 mm shank is a plain cylinder, so it drops into the chuck or collet of a CNC drilling machine, a cutting machine, a machining centre or a multi-head drilling machine. Bits are supplied from 50 PCS per size, and other diameters and lengths can be produced to drawing.

Nine diameters, two lengths and two rotations on one 10 mm shank — what that buys you at the drilling head.

• Carbide-tipped brad point — A centre point and a spur rim locate the bit, so it starts on the mark instead of skating across melamine.
• 5 mm to 15 mm in nine steps — 5, 6, 7, 8, 9, 10, 11, 12 and 15 mm, covering the dowel sizes a cabinet line calls for.
• 57 mm and 70 mm overall — Two lengths let a shallow joint and a deeper one run from the same bit family.
• Right-hand and left-hand — Marked R and L, so counter-rotating spindles on a multi-head machine are covered by one stock item.
• 10 mm cylindrical shank — One shank size across all nine diameters, so a bit change is a straight swap with no collet change.
• Marked shank — Diameter, length and rotation are marked on the shank, for example 5x70L, so a bit out of its box can still be identified.
• Helical flutes — Chips are lifted out of a blind hole instead of being packed into the bottom, which is where a stopped hole usually goes wrong.
• Sizes to drawing — Anything outside the nine standard diameters can be produced to customer requirement, so a non-standard joint needs no second supplier.

A shop usually picks between paying for a custom bit and running a general-purpose bit, then sorting out the holes at assembly. The 40221240 is the third option.

• One stock item per spindle pair. The same diameter and length is stocked in both R and L, so a counter-rotating pair is filled without buying a separate left-hand item or running a spindle empty.
• Hole quality that shows before assembly. A spur-scored rim and a located point are what keep tear-out off the panel face, so less time goes into filling and sanding around dowel joints.
• Fewer changeovers per head. Nine diameters share one 10 mm shank, so a head change is a bit swap rather than a collet change.
• A re-stock size that fits a shelf. 50 PCS per size is an order a workshop can carry, not a pallet it has to store.
• Non-standard joints without a second supplier. Other diameters and lengths are produced to customer requirement, so a one-off joint depth does not need a separate tooling order elsewhere.
• Identification that survives the box. Diameter, length and rotation are marked on the shank, so a loose bit in a drawer can still be read and re-ordered.

Yes, if the head takes a 10 mm cylindrical shank. The same shank is used on all nine diameters, and the bit is used on CNC drilling machines, cutting machines, machining centres and multi-head drilling machines.

Nine: 5, 6, 7, 8, 9, 10, 11, 12 and 15 mm. That is the full standard range; anything outside it is a custom item.

Take the one that matches your joint depth. 57 mm is the shorter of the two and 70 mm the longer, and both mount on the same 10 mm shank.

Both. Every standard diameter is available in R and L rotation, so a counter-rotating spindle pair is filled from one order.

Yes. Other sizes can be produced to customer requirement, which is how non-standard dowel joints are handled.

This one drills a stopped hole for a dowel, not a hole that exits the panel. The brad point and spur cut a clean rim at the surface, and the flutes lift the chip out of the blind hole.

Read the shank. Diameter, length and rotation are marked on it, for example 5x70L for a 5 mm bit, 70 mm long, left-hand.

50 PCS per size is the minimum, and the price is quoted on request. Send the diameters, lengths and rotation you need and the quote is built from that list.