41mm Boring Head Drilling Machine Parts Gear Spindle Gears

A stripped boring head gear is replaced by code, not by machine model. This one is 41 x 12 x 8 mm with 38 teeth, catalogued as 41*12*8-38Z: 41 mm outer diameter, 12 mm inner hole, 8 mm thickness and a 4 mm keyhole. Left-hand and right-hand versions are both available, because the two ends of a boring head turn in opposite directions. It drives the spindle on the drilling head of a woodworking CNC boring machine, and three companion sizes come from the same family.

A multi-spindle boring head almost never fails as a whole. It stops because one gear in the row loses its teeth, because the replacement arrives in the wrong hand and will not mesh, or because the old gear carries no readable code and nobody can re-order it. All three are gear problems, not head problems, and all three are settled by 41 x 12 x 8 mm of steel.

This is the boring head gear that sits on the drilling head of a woodworking CNC boring machine, catalogued as 41*12*8-38Z. Five readings identify it: 41 mm outer diameter, 12 mm inner hole, 8 mm thickness, 4 mm keyhole length, and 38 teeth - the number the 38Z stands for. It is available in both left-hand and right-hand direction, so a pair can be ordered for the two ends of one head.

Three companion sizes cover the rest of a row: 27*12*8*24Z, 34*12*8-31Z and 34*12*12-31Z, and other dimensions are available on request. One order re-gears a whole head instead of one seat at a time, which is why shops that keep a spare keep the whole family. Origin is China; price is quoted on request.

Five readings on the old gear and one direction decide whether the replacement drops straight onto your drilling head:

• 41 mm across, 12 mm bore - the body is 41 x 12 x 8 mm, so the part is matched on three numbers before the teeth are counted.
• 38 teeth - 38Z is 38 teeth on a 41 mm body; a 31Z or 24Z gear will not mesh in that seat.
• Both hands - left-hand and right-hand are both available, because the two ends of one boring head turn in opposite directions.
• 4 mm keyhole - keyhole length is 4 mm, the fifth reading that separates this gear from a look-alike of the same diameter.
• Drilling head seat - the gear drives the spindle on the drilling head of a woodworking CNC boring machine.
• Four sizes, one family - 27*12*8*24Z, 34*12*8-31Z, 34*12*12-31Z and 41*12*8-38Z, so a row is re-geared in one order.
• Other dimensions - sizes outside the four are available on request, quoted from the numbers on your old gear.
• Woodworking drilling spare - listed as a woodworking machinery tool for drilling machines.
• Code-based part - 41*12*8-38Z is the order line; no machine brand, head model or build year is needed to quote it.
• Price on request - the gear is quoted per piece, because price moves with the quantity and the hand.

A stopped boring head gets solved two ways, and both cost more than the gear:

• A gear, not a head rebuild. The 41 mm gear is replaced on its own, so the head casting, the spindle units and the drill holders stay bolted to the machine.
• Measured, not guessed. 41 / 12 / 8 / 4 mm and 38 teeth are five numbers you can check on the old part with a caliper before ordering.
• The right hand the first time. Order left-hand and right-hand together, and the row is not stripped a second time by two gears turning the same way.
• One order, four seats. 27, 34, 34 and 41 mm sizes cover a full head, so the spare is bought once.
• The code is the order. 41*12*8-38Z quotes without a machine serial, so a purchase order can be raised from the shop floor.
• A look-alike is ruled out. A 4 mm keyhole and 38 teeth separate this gear from other 41 mm gears in the same bin.
• No unreadable stamp needed. If the marking is gone, the caliper readings and the tooth count are enough to identify the part.
• Quoted, not listed. Price comes on request, so a mixed order of hands and sizes is priced together instead of piece by piece.

Read five numbers off the old gear. 41 mm outer diameter, 12 mm inner hole, 8 mm thickness, 4 mm keyhole and 38 teeth; the tooth count is the reading that rules a part out, because a 31Z or 24Z gear will not mesh in that seat.

Check the seat, and buy both if both ends are worn. The two ends of one boring head turn in opposite directions, so the same hand cannot serve both, and both directions are available for this gear.

38 teeth. 38Z is the tooth count on a 41 x 12 x 8 mm body, written the same way as 24Z for the 27 mm gear and 31Z for the two 34 mm gears.

27*12*8*24Z, 34*12*8-31Z and 34*12*12-31Z. All three come from the same family as this 41 mm gear, so one order can rebuild a whole row instead of one seat.

Yes. Other dimensions are available on request, quoted from the numbers on your old gear: outer diameter, inner hole, thickness, keyhole and tooth count.

The drilling head of a woodworking CNC boring machine. It is listed as a woodworking machinery tool for drilling machines, at 41 mm outer diameter.

Because two gears can match at 41 mm and still differ there. The keyhole is part of the bore, listed at 4 mm on this gear, so it is measured with the other four readings before a replacement is ordered.

On request. Price is quoted per gear rather than fixed on the page, because it moves with the quantity, the size and the hand; send the code 41*12*8-38Z and the quantity you need.