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Arm Probe Styli Point (Replacement, Custom or Bespoke)

Portable Arm Point

Arm Probe styli points can be manufactured and supplied as a one-piece Tungsten Carbide point. The probe point is supplied with an internal 1.25-20 un thread.

Tungsten Carbide is used as it is incredibly hard-wearing so can be machined to a fine point. This allows the coordinate measuring machine to inspect threaded forms, holes, and smaller parts of an object than, for example, a Ruby or Silicon Nitride ball styli (depending on the ball diameter).

Portable Arm Point - Technical Drawing
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Arm Probe Styli Point (Replacement, Custom or Bespoke) Manufacturing Process

The Tungsten Carbide point is ground and lapped to the required measurements with exceptional precision before attaching it to the stem using an impact-resistant adhesive. We use Tungsten to reduce deflection or excessive bending which can generate greater error issues and reduce accurate measurements.

We let the bond oven cure and then the product will be quality checked. On completed, the probe will go to our despatch department where the stem will be engraved with the serial number before it is cleaned and dispatched to the customer.

Our Quality Guarantee

Accuracy is our trademark at TN UK. We pride ourselves on our ability to measure and calibrate the products we manufacture. Housing some of the most sophisticated equipment in the world, our annually assessed UKAS lab means we guarantee the precision of the products we supply.

On top of that, we maintain regular and open communication directly with you and any relevant departments to ensure that you get exactly what you need when you need it.

We also offer a recalibrate service for your existing gauges, CMM Reference balls and Master Ball Sets. So you can rest assured that, whether we are supplying a new product or recalibrating an existing one, by meeting our strict standards, your company meets its strict standards (particularly important for other calibration assessed companies).



    Technical Drawings
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    PDF (594KB)


    How do CMM arm probes work?

    CMM arm probes tend to be portable units that can be used for measuring objects on a workbench rather than fixed Coordinate Measuring Machines which are housed in a controlled environment. Once the calibration measurements have been input into the software, the arm probe moves (either mechanically or manually) and will touch the object at various points to determine its measurements. An arm probe of this type has a fine stylus tip that allows it to measure smaller & tighter areas than if using a larger ball.

    What are the different CMM machine probe types?

    The most common type of arm probe is the touch trigger probe, meaning measurement data is recorded on the software every time the probe tip physically touches the object. Touch trigger probes can be found on both fixed coordinate measuring machines and on portable CMMs. Fixed CMMs (contained in a lab environment) are the most precise type of CMM as the machine's accuracy is first checked against a calibration sphere.

    Portable Arm CMMs are less accurate as they are used outside of controlled environments and are cable of manoeuvring around more axes than a fixed CMM.

    Non contact CMMs use light or lasers to scan an object and collect measurement data via reflected light. Although considerably quicker than the other types of coordinate measuring machine there tends to be larger tolerances (due to light diffusion etc) so Non Contact CMMs don't produce as accurate measurements as Contact / Touch trigger probe CMMs.

    The final type of CMM is a Displacement or scanning probe and can be a cross between the two mentioned above. Data is collected by measuring and calculating the distances the probe has move from a set point, or by measuring interruptions in a wide set laser field.

    Displacement scanning does offer the flexibility or various axes of non contact CMMs so is used to measure the height, width or thickness of on an object.