FAQ

Products use in OE metal bonding are 1C epoxy products curing during the paint process at high temperatures which cannot be applied for repair processes. Therefore a ambient temperature curing 2C Epoxy is used.

An air pressured gun without piston could lead to extrusion of just one component or air intrusion having a negative effect on the performance. Piston type gun is a must to ensure performance.

As SikaPower®-4720 is filled in a convenient coaxial cartridge a rather high extrusion force is the result which can be lowered by warming up the cartridge before the application.

• Mutli material design does often not allow to weld anymore and requires bonding technology
• High strength steels types lose their performance if they are treated with heat -> Cold repair process with structural bonding combined with rivets lead to optimal repair performance
• Welding applications often involve hours of preparation and dismantling work whereas bonding offers an efficient repair process
• OE assembly is done using bonding technology

The slightly structured surface is caused by glass beads which ensure a perfect bond thickness of 0.3mm and prevents from over clamping.

The round bead guarantees a bond without any air entrapments to ensure optimum strength and corrosion protection.

To ensure best corrosion protection behaviour, SikaPower®-4720 is applied on both bond faces covering all grinded areas.

Yes, SikaPower®-4720 can be spot-welded within the working time.

• The maximum open time is depending on many environmental factors
• High temperatures will shorten the time and dirt and dust will have a negative influence, therefore we recommend in Automotive Glass Replacement applications to clean and repeat the chemical treatment after 2h.

• To mix product from different suppliers is not allowed as compatibility is not ensured.
• Performance and composition of competitor products are not in our control and can change easily without notice.

• The use of dry Sika®Cleaner PCA increases cleaning efficiency as the glass cleaner can act as a lubricant.

• If the surface tension of a substrate is insufficient the primer will show wetting issues on the surface. This is mostly known from non-traditional contaminations present on ceramic frits.
• Remove and clean (Sika®Cleaner PCA), or use glass fit for purpose.

• New paints are difficult to bond as they are developed to be self-cleaning and repellent
• Allow the paint to properly cure first (24h)
• Use abrasive pad to scuff the surface, Sika®Cleaner G+P to clean and apply Sika®Primer-207

• If the old PU is still in place the standard procedure can be followed
• If you bond directly to FRP use abrasive pad to scuff the surface, Sika®Cleaner G+P to and apply Sika®Primer-207

• The PUR adhesive releases carbon dioxide while curing. If the adhesive bead is heated during curing, the gas is released more quickly which can result in small bubbles dispersed throughout the bead. This can happen if the car is parked with the windscreen exposed to sunlight on a warm day. Parking the car in the shade will prevent this problem.

• Soaps and cleaning helps can influence the curing negatively and frameless glasses are sensitive to water pressure and air dryer as they could damage the fresh skin of the urethane, therefore a waiting time of 24h is needed (not needed if installed with Powercure System)

• Sika’s products are intended for use at temperatures between +5°C and +35°C. For all other conditions Sika has special hot and cold weather recommendations. While a job can be carried out at -10°C, there is a question of adequate dexterity with cold hands. It may be too cold to carry out the job to a suitable professional standard. In this case, the job should be deferred.

• To ensure a durable bond, transparent windscreens must be surface-protected against UV. Sika® UV Shielding Tape or trims can be used in cases where no protection is given. Sika Primer (and most glass primers from other manufacturers) are organic materials and will be destroyed by UV radiation within a very short time and therefor provide no durable protection.
  

Possible solutions are:

• Suitable print color.
• Protective metal or opaque plastic trim
• .Sika® UV Shielding Tape.

• Sika® Aktivator PRO and Sika® Primer-207 contain reactive components which react chemically with glass, paint and other materials. Once cured, they can only be removed mechanically and the upper layer of the substrate is damaged in the process. Care must be taken to apply Sika® Aktivator PRO only to the required areas. If the product is applied to the transparent area of the glass, it will be visible and the customer will have cause for complaint.

• Sika® Primer-207 can be cleaned using Sika® Remover-208 or Sika® Handwipes tissues as long as it has not cured completely. Once cured, it must be removed mechanically.