The substrate must be sound, clean, dry and free of all contaminants such as dirt, oil, grease, cement laitance, old sealants and poorly bonded paint coatings which could affect adhesion of the adhesive.
Removal techniques such as wire brushing, grinding, sanding or other suitable mechanical tools can be used.
All dust, loose and friable material must be completely removed from all surfaces before application of primers or adhesive.
For optimum adhesion and critical, high performance applications the following priming and/or pre-treatment procedures shall be followed:
Non-porous substrates
Aluminium, anodised aluminium, stainless steel, PVC, galvanised steel, powder coated metals or glazed tiles. Slightly roughen surface with a fine abrasive pad. Clean and pre-treat using Sika® Aktivator-205 applied with a clean cloth.
Before application of adhesive, allow a waiting time of > 15 minutes (< 6 hours).
Other metals, such as copper, brass and titanium-zinc, cleaned and pre-treat using Sika® Aktivator-205 applied with a clean cloth. After a waiting time of > 15 minutes (< 6 hours). Apply Sika® Primer-3 N applied by brush. Allow a further waiting time of > 30 minutes (< 8 hours) before application of adhesive.
Porous substrates
Concrete, aerated concrete and cement based renders, mortars and bricks. Prime surface using Sika® Primer-3 N applied by brush.
Before application of adhesive, allow a waiting time of > 30 minutes (< 8 hours).
For more detailed advice and instructions contact Sika Technical Services.
Note: Primers are adhesion promoters and not an alternative to improve poor preparation / cleaning of the bonded surface. Primers also improve the long term adhesion performance of the bonded surfaces.
