Mineral Surfaces, Natural Stone, or Stucco
What to keep in mind when applying adhesive tape to mineral surfaces, natural stone and stucco or plaster.
Metal as well as artificial or natural stone surfaces require particular care when applying adhesive – as their micro-porous structure is much more vulnerable than the seemingly solid base coat might suggest.
What to keep in mind when applying adhesive masking tape to mineral surfaces, natural stone and stucco or plaster:
For untreated metals such as zinc, titanium zinc alloys and copper, protective measures such as films can lead to the build-up of condensation and thus to corrosion. This can be prevented by using masking materials open to diffusion, such as non-woven fabric without film. Alternatively, the adhesive can be applied for a short time or over the full surface.
All metal surfaces are subject to a natural oxidation and aging process. When adhesive tape is applied to metal, the oxidation and aging of these specific areas is reduced. This may cause these areas to have a different appearance from the rest of the surface once the adhesive tape is removed. This cannot be prevented. However, depending on the type of metal, the area will take on a uniform appearance within a short period (over several months).
In the case of treated metals, damage (such as discolouration and peeling) of the coating may occur.
The adhesion conditions, especially regarding temperature, must be taken into account.
Experience has shown that natural stone is a critical surface for adhesives. Discolouration was noticed in areas where adhesives were applied.
Adhesive tapes marketed as “stone tapes” are suitable for use on materials such as concrete and stucco or plaster, but not for natural stone.
Natural stone should be covered with felt or nonwoven fabric that is open to diffusion, without any adhesive bonding. Another protective measure that can be used for this kind of surface is plywood sheets, which shield the material from mechanical damage or slippage.
It was once common to use paper (often newspaper) and paste as a protective measure on natural stone, but that method is seldom used today.
For structured stucco surfaces, high-adhesion tapes that follow the contours of the surface should be used. A fabric adhesive tape, or a PVC backed adhesive tape for instance like tesa 4843 can be used
In the case of smooth stucco, low-adhesion tapes should be used. The backing material should be selected according to the work that is to be performed later: paper tape for coating or painting work; fabric tape for plastering work, grinding work, mechanical strain and the like.