Joint Design
- Correct joint design should have minimum joint width of 6mm, minimum joint depth of 6mm.
- For larger joints, the width of the joint should be greater than the sealant depth.
- Avoid 3-sided adhesion; apply backer rod or bond breaker tape in the base of the joint to ensure the sealant is only bonded to the sides of the joint and is free to move to its full capacity under joint movement.
Preparation and Cleaning
- Substrates must be clean prior to application to ensure adhesion durability.
- All surfaces must be clean from contaminants and residues such as grease, oil, dust, water, frost, surface dirt, old sealants or glazing compounds and protective coatings.
- Solvent should be wiped on and off with clean, oil- and lint-free cloths.
- DOWSIL™ R-40 Cleaner is recommended for cleaning of non-porous substrates.
- The ventilation time at room temperature should be at least 1 minute.
- Please contact your local technical service expert for more information.
Priming
- For each project separately, it is essential that adhesion to all concerned surfaces should be tested before application.
- If adhesion requires priming, a primer such as DOWSIL™ 1200 OS Primer is in general recommended for metal substrates and DOWSIL™ Primer P for mineral substrates.
- While priming, note the ventilation time at room temperature which is indicated on the primer label.
- Priming should be done within 4 hours after cleaning.
- If there is a greater time delay, cleaning process has to be repeated again.
- Project specific priming regulation needs to be discussed and approved by your local technical department.
- Please contact your local technical service engineer for further assistance.
Installation
- Install back-up spacing material for better filling, especially if the width exceeds 1/2" to maximize bonding results.
- Open-cell polyethylene foam backer rod can be used.
Masking
- Apply masking tape to areas adjacent to the joint to ensure straight bead lines and easy clean-up.
- Remove masking tape immediately after the bead is completed and before a skin is formed.
Open cartridge
Cut snub nose above threads, reattach and cut nozzle to desired size. Insert into a caulking gun.
Application
Extrude sealant with a smooth, steady motion, and ensure complete fill of joint cavity before proceeding.
Tool
Tool the sealant immediately after application and before a skin forms. Remove masking immediately after tooling.
Replace cartridge cap
See “Shelf Life and Storage” instructions.
