TCT Dowel Drill Bit Two Flutes Blind Hole Drilling Head Woodworking Tools

Need a dowel hole that stays round when the bit leaves the panel? This TCT dowel drill bit puts a two-flute blind hole drilling head on a 10 mm shank, so chips clear the hole instead of packing it, and the tungsten carbide edge keeps cutting in abrasive board. Two total lengths — 57 mm and 70 mm — cover the common panel builds, and both left-hand and right-hand rotation are supplied, so the bit follows the spindle you already run. Used on standard drilling machines.

Three things go wrong with dowel holes on a boring head: the bit walks off the mark on the entry face, chips pack into the flutes and scorch the wall, and in melamine or MDF the edge is finished before the run is. This bit is built for those three.

It is a TCT dowel drill bit with a two-flute blind hole drilling head, used on the drilling machine in cabinet and furniture work. The cutting edges are tungsten carbide on a steel body, and the two flutes lift chips out of the blind hole instead of letting them rub the wall. The shank is 10 mm on both bodies; total length is 57 mm or 70 mm.

Rotation comes in two versions, left-hand and right-hand, so the bit is matched to the direction your spindle turns instead of being forced onto it. The body is orange / black, which makes a bit identifiable at the tool board at a glance.

The characteristics listed for this bit are long service life, sharp blade and strong perforation. In a shop those decide cost per hole, not price per piece: an edge that holds its form means fewer stops, and a blind head that stops at depth means no second operation to plug a breakthrough. Where one head runs two panel thicknesses, the 57 mm and 70 mm bodies cover both.

What separates this bit on a boring head, in real numbers:

• Two flutes. Two cutting flutes carry chips out of the blind hole, so the wall is cut once instead of being rubbed by debris with nowhere to go.
• TCT cutting edges. Tungsten carbide on a steel body — the carbide meets the abrasive panel surface every shift, which is what the listed long service life of this bit means.
• 10 mm shank. One shank size drops into the boring heads already bolted to the machine, with no adapter and no second chuck.
• 57 mm and 70 mm bodies. Two total lengths on the same 10 mm shank cover shallow and deep dowel stacks without a second part number.
• Left and right rotation. Both L/R versions are supplied, so the bit matches the spindle direction instead of the spindle being reversed for it.
• Blind hole head geometry. The head is made for blind drilling: the hole stops at set depth and the far face of the panel is left whole.
• Sharp blade, strong perforation. Listed characteristics of this bit: the edge is ground sharp as supplied, and it drives into the panel instead of riding on a hardened skin.
• Orange / black body. Two-tone colour means a bit with the wrong rotation or length is spotted on the board before it reaches the chuck.

A boring head usually leaves two options: a cheap brad-point bit that gives up in abrasive board, or a special-order tool that will not fit the head you already own.

• One shank, every head on the floor. A 10 mm shank goes into the boring heads already installed, so there is no adapter to buy and no re-setup when the bit moves to the next machine.
• Two lengths, one line on the stock list. 57 mm and 70 mm cover shallow and deep stacks from a single part, so the spares shelf stays small while the head still handles both panel builds.
• Rotation is chosen, not adapted. Both L/R directions are supplied, so a spindle that turns the other way does not need a modified bit or a reversed head.
• Chips leave the hole. Two flutes carry debris out as the bit turns; a packed blind hole is what scorches the wall and shows as a dull ring on the finished panel.
• The carbide edge is the wear part. TCT edges meet the abrasive surface directly, so the cost lands on a replacement bit instead of on reworked panels.
• Depth stops at the blind end. The head is made for blind drilling, so the visible face of the panel stays unmarked and no plug or dowel cap is needed afterwards.

Yes, if the head takes a 10 mm shank. Check that single number first: the shank is 10 mm on both the 57 mm and the 70 mm body, and rotation is available left or right, so the fit is decided by the shank and the spindle direction, not by the machine make.

Pick by the deepest dowel stack you drill. 57 mm covers the shallow builds; 70 mm reaches through the thicker one. Both run the same 10 mm shank, so the head does not need changing between the two.

Because a blind hole has only one way out for the chips. Two flutes lift debris out on each turn, so the wall is cut by the edge instead of being rubbed by material that is still in the hole.

Look at the direction the spindle turns when you face the head. Both L/R bits are supplied; ordering the opposite one runs the edge backwards, which scorches the hole and takes the edge off in a single panel.

Tungsten carbide tipped: the cutting edges are carbide on a steel body. That is the part that keeps an edge in abrasive panel products, and it is the part that wears rather than the 10 mm shank.

Not if the edge is sharp — face splintering comes from a dull cutting edge, not from the bit type. Sharp TCT edges plus two-flute chip clearance give a clean entry and a clean exit on the blind side.

No. It is a TCT two-flute blind hole drilling head with a 10 mm shank for a machine boring head, not a hand-drill bit; the shank, the rotation direction and the head geometry are what place it on a drilling machine.

Three numbers: the shank (10 mm), the length you want (57 mm or 70 mm) and the rotation direction (L or R). Add the panel stack you drill and how many heads you run, and the quotation covers the right bit the first time.