Specifications

CG204-EU-EN v2.2 8/13
10
CalibratingforShotblastedsurfaces
Thephysicalnatureofshotblastedsurfacesresultsinhigherthannormalcoatingthicknessreadings.The
meanthicknessoverthepeakscanbedeterminedasfollows:
1. Themetershouldbecalibratedaccordingtothecalibrationinstructions.Useasmoothcalibration
samplewiththesamecurvatureradiusandthesamesubstrate
asthedevicetobetested.
2. Takeapprox.10readingsontheuncoated,shotblastedsampletoproducethemeanvalueXo.
3. Takeanadditional10readingsonthecoated,shotblastedtestsampletoproducethemeanvalueXm
4. Thedifferencebetweenthetwomeanvalues
isthemeancoatingthicknessXeffoverthepeaks.The
greaterstandarddeviation‘S’ofthetwovaluesXmandXoshouldalsobetakenintoconsideration:Xeff
=(Xm‐Xo)±S
NOTE:Forcoatingsthickerthan300µm,theinfluenceofroughnessgenerallyisofnoimportanceand
thereforeitisnotnecessarytoapplytheabovecalibrationmethods.