Optimize machining time with a tapping arm outside your CNC

May 05, 2023 - 02:00pm

By Dave Sawicki, IPT America

CNC time is expensive, and engineers always look to decrease machining time to improve productivity. Today’s operations managers need more skilled help and are strategizing to reduce cycle time, automate more processes and be more productive. 

Many of these operations look to remove the tapping process from the CNC machine to save machining time, improve efficiency and be more flexible, especially when shifting from one job to another. For example, one job may require making 500 parts with the same size threaded hole, then switch to a job with different hole size specifications. An external tapping arm allows for this versatility with fewer adjustments.

If your CNC operation calls for tapping or deburring, you can be more productive if you turn the process around, automating deburring inside the CNC and performing the tapping outside it.

The case to invest in a high-tech CNC drilling and tapping center 
Taps require relatively slow spindle speeds, so tapping is one of the slowest milling processes. If holes of several sizes are specified, tool changes can make the process longer. You can realize gains in speed, accuracy and productivity by placing a tapping arm next to the machining center and shifting the tapping process outside the machine. Eliminating tapping from the milling process decreases cycle time, and while the CNC is milling the next part, the operator can tap holes in the previously milled part in less time. 

And with that machine time you save by moving tapping outside the CNC, you can add automated deburring inside the CNC after milling, which adds a few minutes to machine time but further improves productivity. Using ceramic fiber brushes for CNC deburring will reduce overall production time by eliminating the hours spent on manual deburring. 

Automated deburring has the added benefit of producing high-quality finished products consistently and reliably. And your CNC center will no longer need to wait on manual or outsourced deburring before shipping the parts.

How a tapping arm maximizes production in your CNC center 
One CNC center reduced the cycle time of a part by 11 minutes by using a tapping arm outside the CNC after milling. The part required 30 tapped holes, and the original milling, drilling and tapping cycle time was two hours each. Using a tapping arm, the operator reduced CNC cycle time and tapped out 30 holes in just three minutes while the next part was running. As a result, the center lowered cycle time by 7.3% and, in a facility with 10 CNCs, can produce 800 – 1000 more of these parts per year. 

Plus, quick-change tap adapters make tapping different hole sizes fast and easy. For example, it takes seconds to switch adapters on a tapping arm, so you can accomplish tapping threaded holes of differing sizes much more quickly than using other methods. 

By adding a few minutes to machine cycle time with automated deburring, then externalizing the tapping process, CNC operations can reduce- the cycle time for each part. 

Beyond productivity – gain flexibility and innovate your operations
Tapping arms also allow for more flexibility in your workspace. Lightweight, mobile tapping arms can bring the tap to the work, which is three to four times more efficient than carting the workpiece to a fixed spindle. Tapping arms are also capable of secondary options such as reaming, countersinking, and drilling small holes and make it easy with high-speed motors, speed control variators and interchangeable speed modules. Integrating a tapping arm with robotics can also automate the tapping process.

Think outside the box – or rethink what operations you do inside and outside your CNC to optimize production. Pair your CNCs with the newest technologies in deburring and tapping to increase quality and efficiency.

Author Bio: Dave Sawicki is the Senior Application Specialist and Sales Director of IPT America –  Improving manufacturing productivity with Roscamat USA tapping arms and Xebec Deburring Technologies, automated deburring and surface finishing solutions. Contact Dave at dsawicki@deburringtechnologies.com.

Related Glossary Terms

  • computer numerical control ( CNC)

    computer numerical control ( CNC)

    Microprocessor-based controller dedicated to a machine tool that permits the creation or modification of parts. Programmed numerical control activates the machine’s servos and spindle drives and controls the various machining operations. See DNC, direct numerical control; NC, numerical control.

  • countersinking


    Cutting a beveled edge at the entrance of a hole so a screw head sits flush with the workpiece surface.

  • gang cutting ( milling)

    gang cutting ( milling)

    Machining with several cutters mounted on a single arbor, generally for simultaneous cutting.

  • inches per tooth ( ipt)

    inches per tooth ( ipt)

    Linear distance traveled by the cutter during the engagement of one tooth. Although the milling cutter is a multi-edge tool, it is the capacity of each individual cutting edge that sets the limit of the tool, defined as: ipt = ipm/number of effective teeth 5 rpm or ipt = ipr/number of effective teeth. Sometimes referred to as the chip load.

  • machining center

    machining center

    CNC machine tool capable of drilling, reaming, tapping, milling and boring. Normally comes with an automatic toolchanger. See automatic toolchanger.

  • milling


    Machining operation in which metal or other material is removed by applying power to a rotating cutter. In vertical milling, the cutting tool is mounted vertically on the spindle. In horizontal milling, the cutting tool is mounted horizontally, either directly on the spindle or on an arbor. Horizontal milling is further broken down into conventional milling, where the cutter rotates opposite the direction of feed, or “up” into the workpiece; and climb milling, where the cutter rotates in the direction of feed, or “down” into the workpiece. Milling operations include plane or surface milling, endmilling, facemilling, angle milling, form milling and profiling.

  • robotics


    Discipline involving self-actuating and self-operating devices. Robots frequently imitate human capabilities, including the ability to manipulate physical objects while evaluating and reacting appropriately to various stimuli. See industrial robot; robot.

  • tap


    Cylindrical tool that cuts internal threads and has flutes to remove chips and carry tapping fluid to the point of cut. Normally used on a drill press or tapping machine but also may be operated manually. See tapping.

  • tapping


    Machining operation in which a tap, with teeth on its periphery, cuts internal threads in a predrilled hole having a smaller diameter than the tap diameter. Threads are formed by a combined rotary and axial-relative motion between tap and workpiece. See tap.


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