All surfaces must be structurally sound, clean, dry and free from grease, oil, wax, dust and surface contaminats such as curing compounds, release agents, coatings and friable material. Sikaflex®-11FC adheres without primers and/or activators. However, for optimum adhesion and critical, high performance applications, such as on multi story buildings, highly stressed joints, extreme weather exposure or water immersion, the following priming/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 bonding / sealing, allow a waiting time of > 15 minutes (< 6 hours). Other metals, such as copper, brass and titanium-zinc, clean 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 bonding / sealing. PVC has to be cleaned and pre-treated using Sika® Aktivator-215 with a clean cloth. Before bonding / sealing, allow a waiting time of > 15 minutes (< 6 hours).
Porous substrates: Concrete, aerated concrete and cement based renders, mortars and bricks, prime surface using Sika® Primer-3 N applied by brush. Before bonding / sealing, 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 joint surfaces. Primers also improve the long term adhesion performance of the sealed joint.