It is a replica tape for measuring blasted surface profiles. By placing the Tqc replica tape on the surface and rubbing over it, the Rt (total roughness) or peak-to-valley height of the profilecan be taken and then measured with a film thickness meter.
1. TQC Replica tape consists of a layer of compressible foam affixed to an incompressible polyester substrate.
2. When pressed against a roughened/gritblasted (steel) surface, the foam collapses acquiring an impression of the surface.
3. Placing the compressed tape between the anvils of the micrometric thickness gage, and subtracting the contribution of the incompressible substrate (50 micrometers or 0.002 inches), gives a measure of the surface profile.