Sagging

Good non-sag properties

Ambient air temperature

+5 °C min. / +40 °C max.

Substrate temperature

+5 °C min. / +40 °C max., min. 3 °C above dew point temperature

Backing material

Use closed or open cell, polyethylene foam backing rod

Curing rate

Skin time

EQUIPMENT

Sikaflex®-127 sausages is applied with hand operated closed type cartridge gun and cartridges is applied with open type cartridge gun. Similar pneumatic or battery-operated guns may also be used.

SUBSTRATE QUALITY

• 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 / sealant.
• The substrate should be of sufficient strength to resist the stresses induced by the sealant during movement.

SUBSTRATE PREPARATION

All substrates

• 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 any activators, primers or adhesive / sealant.

Sikaflex®-127 adheres without primers and/or activators. Primers are adhesion promoters and not an alternative to improve poor preparation / cleaning of joint surfaces. For optimum adhesion, joint durability and critical high-performance applications the following priming and/or pre-treatment procedures shall be followed:

Non-porous substrates

• Aluminium, anodised aluminium, stainless steel, galvanised steel, powder coated metals, glazed tiles, plastic or PVC: 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® Cleaner P or Sika® Aktivator-205 applied with a clean cloth. After a waiting time of > 15 minutes (< 6 hours). Apply Sika® Primer-3 applied by brush. Allow a further waiting time of > 30 minutes (< 8 hours) before bonding / sealing.

Porous substrates

• Concrete, aerated concrete and cement-based renders, mortars and bricks: prime surface using Sika® Primer-3 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.

APPLICATION

IMPORTANT

Sikaflex®-127 can be applied between +5 °C and +40 °C but changes in reactivity and application properties must be considered. The optimum temperature for substrate and sealant is between +15 °C and +25 °C.

Bonding Procedure

1. After the necessary substrate preparation, prepare the end of the cartridge before or after inserting into the sealant gun then fit the nozzle.
2. Apply in beads, strips or spots at intervals of a few centimetres each. Use hand pressure only to fix the components to be bonded into position before skinning of the adhesive occurs. Incorrectly positioned components can easily be unbonded and repositioned during the first few minutes after application. If necessary, use temporary adhesive tapes, wedges, or supports to hold the assembled components together during the initial curing time.
3. Fresh, uncured adhesive remaining on the surface must be removed immediately. Final strength will be reached after complete curing of Sikaflex®-127, i.e. after 24 to 48 hours at +23 °C, depending on the environmental conditions and adhesive layer thickness.

Sealing Procedure

Masking

It is recommended to use masking tape where neat or exact joint lines are required. Remove the tape within the skin time after finishing.

Joint Backing

After the required substrate preparation, insert a suitable backing rod to the required depth wherever necessary.

Priming

Prime the joint surfaces as recommended in substrate preparation. Avoid excessive application of primer to avoid causing puddles at the base of the joint.

Application

Prepare the end of the cartridge before or after inserting into the sealant gun then fit the nozzle. Extrude Sikaflex®-127 into the joint ensuring that it comes into full contact with the sides of the joint and avoiding any air entrapment.

Finishing
As soon as possible after application, sealant must be firmly tooled against the joint sides to ensure adequate adhesion and a smooth finish.
Use a compatible tooling agent (e.g., Sika® Tooling Agent N) to smooth the joint surface. Do not use tooling products containing solvents.

Overpainting
Sikaflex®-127 can be best painted by allowing the sealant to fully cure first. All paints must be tested by carrying preliminary trials under manufacturing conditions. The elasticity of paints is usually lower than that of sealants. This could lead to cracking of the paint in the joint area.

CLEANING OF TOOLS

Clean all tools and application equipment immediately after use with Sika® Remover-208. Once cured, hardened material can only be removed mechanically.
For cleaning skin use Sika® Cleaning Wipes-100.