Vetoflex SN790

Vetoflex SN790 should be applied following proper joint design principles. The sealant must accommodate joint movement and adhere effectively to the substrate while preventing three-sided adhesion. A closed-cell polyethylene or polyurethane foam backer rod should be used to control the joint depth and provide a firm backing for the sealant. The backer rod must maintain a uniform, compression fit against both joint faces along its entire length.

For optimal joint performance, the sealant depth should be maintained at approximately half of the joint width, following the recommended dimensions below: 

Joint Depth Guidelines: 

 • Minimum joint depth: 6 mm 

 • Maximum joint depth: 12 mm 

 • For joints wider than 25 mm, consult Saveto Technical Support for customized recommendations.

The joint faces to be bonded must be clean, dry and free from dust, oil, grease, old sealant and any traces of contaminant which may impair adhesion performance. Surfaces should be degreased with solvent soaked cloth and then wiped with a clean cloth. To remove dust, use oil-free compressed air. If water flushing is required, it must be performed in one direction only to minimize contamination. After drying, the upper 25mm of each joint face should be sandblasted

separately, with the nozzle positioned at an angle no greater than 50mm from the surface. Newly poured concrete must undergo a minimum 7-day curing and drying period to achieve the necessary structural integrity before Vetoflex SN790 application. Prior to installation of backer rod, all joints must be meticulously cleaned to remove dust, debris, and impurities, ensuring a completely dry and uncontaminated surface.

For most substrates, Vetoflex SN790 does not require a primer. However, when applying the sealant to specialized substrates, a preliminary test is recommended to determine whether priming is necessary. 

In general, for non-porous materials like glass and metal, a primer is not needed. However, the surface must be clean and dry before applying the sealant. For porous surfaces such as concrete, mortar, render, and brick, the application of a suitable primer is recommended to enhance adhesion and improve long-term performance of the sealant. Proper priming ensures a strong bond and helps prevent potential adhesion failures over time.

For optimal sealant performance, the application must ensure that the sealant bond is restricted to the two facing sides of the joint allowing for proper movement accommodation. A closed-cell polyethylene or polyurethane backer rod should be used to provide a firm backing for the sealant. 

Before applying Vetoflex SN790, a masking tape should be placed along the joint edges to ensure clean, precise lines and prevent excess sealant from spreading onto adjacent surfaces. 

Next, position an appropriately sized backer rod into the joint, ensuring a tight, compression fit against both joint faces, to accurately control the joint depth and maintain uniform sealant thickness. Once the backer rod is securely in place, extrude the sealant into the joint with a sealant gun, using a continuous bottom-up motion to prevent air entrapment and ensure full contact with the joint sides. 

Immediately after application, lightly tool the sealant using a rounded or flat spatula to ensure proper bond to the joint faces and create a slight recess below the surface, allowing for expansion and contraction. Once the sealant has begun to cure (skinning time), carefully remove the masking tape to achieve clean, well-defined joint lines.

Remove Vetoflex SN790 from tools and equipment with Vetonit Solvent XX400 immediately after use. Wipe off any excess uncured material from the substrate using the same solvent. Hardened material can only be removed mechanically.