70mm Carbide Blind Hole Drill Bit For Woodworking Drill Bits Carpenter Tools

Need hinge, dowel and shelf holes from one bit family? The PRO-BH70 is a 70 mm carbide blind hole drill bit with 4 spiral flutes in tungsten alloy cut behind a hard metal head. It covers 3 mm to 15 mm in 23 diameters, takes a 10 mm shank up to a 10 mm bore (11 mm to 17 mm above that), and comes left-hand in orange and right-hand in black. Each bit is tubed individually, 50 pcs to the carton; a 57 mm length is also made.

A shop that bores dowel and hinge holes every day meets the same three things: a bit that splinters the melamine face on entry, a bit that walks off the centre line in hard wood, and a length that fights the boring head when the board changes. The PRO-BH70 is a 70 mm carbide blind hole bit with 4 spiral flutes, built to remove all three.

It is a carbide blind hole drill bit — a dowel bit with 4 spiral flutes cut in tungsten alloy behind a hard metal head carrying a balanced centre point. Diameters run from 3 mm to 15 mm across 23 sizes, 4.8 mm and 6.2 mm included, so hinge, dowel and shelf holes come from one family. Every size is 70 mm overall; 57 mm is also available.

Left-hand bits are orange, right-hand bits are black, and both directions are made in every diameter — the detail that matters on a multi drill head where neighbouring spindles turn opposite ways. The shank runs concentric to the flutes, so 10 mm holds everything up to a 10 mm bore and 11 mm to 17 mm covers the rest.

It is ground for board work: MDF and HDF, hard wood, light wood, plywood, particle board, blockboard, chipboard and melamine faced board. Each bit ships in its own transparent plastic tube, 50 pcs to the export carton.

A blind hole bit is bought on three numbers — diameter, length, shank:

• 4 spiral flutes in tungsten alloy — four cutting edges per turn, cut in tungsten alloy rather than plain carbon steel.
• Hard metal head — the point carries a balanced centre, so the bit starts where it is put on hard wood.
• 3–15 mm in 23 sizes — 3, 3.5, 4, 4.5, 4.8, 5, 5.5, 6, 6.2, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 11, 11.5, 12, 13, 14 and 15 mm.
• 70 mm overall — one length through the whole range; a 57 mm version is also available.
• Stepped shank — 10 mm from 3 mm to 10 mm bore, then 11 mm to 17 mm as the bore grows to 15 mm.
• Left and right hand — left-hand in orange, right-hand in black, both directions in every diameter.
• Precise cutting edges — the edge geometry is ground to cut the rim clean and help prevent splintering.
• Engineered flutes — the flute form is set for reliable chip removal down a 70 mm hole.
• Concentric shank — the shank runs true to the flutes, so the centre of rotation stays balanced at speed.
• Individually tubed — one bit per transparent plastic tube, 50 pcs to the carton, so bits issue singly.
• Customisable — diameter, length, colour and packing are made against a confirmed drawing.

Buying a blind hole bit usually comes down to two poor options: a two-flute twist bit that splinters the face, or an outside boring job that eats a week. The PRO-BH70 removes that choice:

• One family, not five boxes. 23 diameters from 3 mm to 15 mm on one 70 mm length, so hinge, dowel and shelf holes stop needing separate part numbers.
• Clean rims off the machine. four flutes and ground cutting edges help prevent splintering, so fewer panels reach the scrap bin.
• The bit goes back in the right spindle. orange is left-hand, black is right-hand, read at a glance on a multi drill head.
• Chips leave the hole. engineered flutes carry chips out of a 70 mm bore instead of packing it halfway.
• Balanced at speed. a concentric shank holds the centre of rotation, which is what keeps hole position on the line the pattern asked for.
• Shank sized to the bore. it steps from 10 mm to 17 mm as the bore grows to 15 mm, so load sits on the right diameter.
• Stores issue singly. every bit is tubed and cartoned 50 pcs at a time, so spare parts leave the shelf one piece at a time.
• Private label without a container. diameter, length, colour and packing are customisable against a confirmed drawing, so a branded run can start from one confirmed sample.

Twenty-three diameters, from 3 mm to 15 mm. The steps include 3, 3.5, 4, 4.5, 4.8, 5, 5.5, 6, 6.2, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 11, 11.5, 12, 13, 14 and 15 mm, and every one of them is 70 mm overall.

No. The shank is 10 mm from 3 mm up to a 10 mm bore, then it steps up with the diameter: 11 mm at 10.5 mm, 12 mm at 11 mm, 13 mm at 11.5 mm, 14 mm at 12 mm, 15 mm at 13 mm, 16 mm at 14 mm and 17 mm at 15 mm.

By colour. Left-hand rotation is orange, right-hand rotation is black. Both directions are made in every diameter, so a head with opposed spindles can be loaded from one order.

MDF and HDF, hard wood, light wood, plywood, particle board, blockboard, chipboard and melamine faced board. It is a wood and wood-based-material bit — board work, not metalwork.

CNC machines, multi drill machines, vertical assembling machines and woodworking drilling machines. It is a CNC woodwork tool, used for boring blind and dowel holes on boards and panels.

Yes. 57 mm overall length is also available alongside the 70 mm standard, on the same diameter range and the same shank steps — state the length on the order.

Splintering is kept down by the edge geometry: 4 spiral flutes and precise cutting edges. Board grade and feed rate still decide the finished rim, so test on your own melamine faced board before a full run.

One bit per transparent plastic tube, 50 pcs to the export carton, shipped by air, by sea or by express. Customisation is supported — diameter, length, colour and packing to a confirmed drawing.