Renishaw ATOM Installation Manual page 29

1. Using a digital dial gauge or similar, measure the distance from the readhead mounting surface to the disc surface.
Care must be taken to ensure the disc surface is not scratched. Renishaw offer a DTI adapter (A-9401-0105) that can be used
to assist with this process.
• Insert the gauge into the adapter and zero the gauge on a flat surface.
• Position or fix the gauge / adapter in place of the readhead and measure the distance to the disc surface.
Contact your local Renishaw representative for details of the DTi adapter and digital dial guage.
2. Subtract the distance measured from the nominal rideheight of 2.5 mm to calculate the required shim thickness. For example if
the distance measured is 2.37 mm the required shim thickness is 130 µm.
3. Select a combination of two shims that gets within 10 µm of the difference. For distances less than 100 µm a single shim
should be used; for distances greater than 100 µm select one thick (≥ 100 µm) and one thin (< 100 µm) shim. In the above
example this could either be 1 × 100 µm shim and 1 × 40 µm shim or 1 × 100 µm shim and 1 × 20 µm shim.
4. Place the chosen shim(s) between the readhead and the bracket.
5. Fix the readhead to the bracket using two off M2 × 6 screws in diagonally opposite fixing holes, ensuring readhead is tightened
down evenly and parallel to the bracket face.
Using location pins/shoulder:
6. Ensure the readhead is pushed back against the location pins or shoulder.
7. Tighten the fixing screws.
8. Check the readhead set-up LED is green around the full axis of rotation
9. Proceed with 'System calibration' on page 34.
Not using location pins:
10. Adjust longitudinal and radial offset of the readhead to obtain a green readhead set-up LED around the full axis of rotation. An
oscilloscope or Renishaw USB set-up tool kit and software can be used to help maximise the signal size. For more information
on the Renishaw USB set-up tool kit contact your local Renishaw representative.
11. Tighten the readhead fixing screws.
12. Proceed with 'System calibration' section.
DTI adapter
RCDM
disc
www.renishaw.com 29