A-510 2-Axis Target 10×10 PSD for Self-Centering Bore Adapters

A-510 2-Axis Target 10×10 PSD for Self-Centering Bore Adapters


The A-510 2-Axis Bore Target is a general-purpose, 2-axis target comprised of a target and an insertion pole or handle. It is used with our A-510STA (2 in. to 5 in.) or A-510LTA (4.25 in. to 16 in.) Bore Adapters Hubs and, a set of M-705CL Customized Set of 4 Measuring Legs, to measure the alignment of bores from 2.25 in. to 16 in. (57.2 mm to 406.4 mm). The M-705CL legs are replaceable and customized for each bore, so only 1 bore adapter hub is needed for the specified range.

The adapter can be attached to the target in either Self-Centering Mode or Measurement Mode.  In Self-Centering Mode, the target automatically centers itself in any bore size that is +/- .030 in. (+/- 0.8 mm) from the adapter bore diameter.

The self-centering concept works by carefully centering the target PSD sensor axially between the feet. This puts the target cell on the pivot point of the adapter and legs and allows it to vary by up to 45º without affecting the center. One pair of adapter legs are offset from the other, so when it is inserted in the bore (by pulling on the cord and tipping it forward) and the cord is released and the weight of the pole or handle “jams” the target/adapter into the bore, centering itself.

In Measurement Mode, the target will measure changed in bore diameter. First, a reference diameter is measured with an inside micrometer. Next, the target is placed in the reference bore and the reading is noted. The target is then inverted and the readings averaged to calculate the target centering error. The corrected reading becomes the benchmark diameter. Subsequent measurement points in the bore are compared to the benchmark and the difference in target readings is the increase or decrease in bore diameter.

The accuracy of the measurement of the A-510 with the bore adapter and legs is .0005 in. (0.013 mm) with repeatability to .0002 in. (0.005 mm) in well machined bores.


  • Any bore application with minimum of 2.25 in. (57.2 mm) diameter
  • Boring-bar bearing supports
  • Compressor bores – alignment both concentricity and angular
  • Cylinder straightness up to 25 feet (7.6 m)
  • Extruders – single or twin barrels – up to 25 feet (7.6 m)- alignment and straightness checks
  • Engine block crankcase bores – alignment both concentricity and angular


  • Self-centering, 2-axis target accurate to .0005 in. (0.013 mm) with a resolution of up to .0001 in.  (0.001 mm) using R-1307 Readouts
  • Measures bore straightness in Self-Centering Mode, or bore diameter changes in Measuring Mode.
  • Tips on adapter feet use hardened carbide steel balls that rarely wear out.
  • Target with adapters can handle diameter variations up to of +/- .030 in. (0.8 mm).
  • Rugged, portable and very lightweight.
  • Uses the following bore adapters:
  • A-510STA Small-Bore Adapter Hub for bores from 2.25 in. to 5 in. (57.2 –170.0 mm)
  • A-510LTA Large-Bore Adapter Hub for bores from 5 in. to 16 in. (127 mm – 406.4 mm)
  • M-705CL Customized Set of 4 Measuring Legs. Note legs are replaceable and each bore diameter requires 1 set of M-705CL legs.


Target Cell 
Concentricity to Housing:
.0003 in. (0.0075 mm) T.I.R. to 1.1248 in. (28.6 mm) OD of target housing
Target Resolution:
.00002 in. (0.0005 mm) with Bore9 Software or the R-358 Computer Interface
.0001 in. (0.001 mm) with the R-1307 Readouts
Target PSD Range:
+/- .080 in. (2.0 mm) with 5 mm diameter laser beam
Within 1-5% (See Target Cell Accuracy for details)
Cord Dimensions:
Target to connector 10 ft. (3 m), rubber
Material Hardness:
440C stainless Rockwell RC55-60
14 oz (392 g)
Mounting Dimensions:
1.1248 in. O.D. (28.570mm)