Polyurethane 103 Injection Foam for Wider Cracks

1. Prepare the crack. Remove loose concrete, dust, and debris along the full length of the crack so the surface seal and ports bond cleanly.
2. Set the ports. Place surface ports over the crack at intervals roughly equal to the wall thickness, starting at the bottom and working up.
3. Seal the face. Apply surface seal paste over the crack between ports to cap it, leaving the port openings clear. Allow the seal to set.
4. Load the tool. Insert the dual 600ml cartridge into the dual 300mL cartridge tool, attach the retaining nut, and fit the recommended 3/8 x 24 static mixer — the 1/4 x 24 also fits, but the wider 3/8 x 24 suits 103's faster, more aggressive foam.
5. Do not use a feed hose. Because 103 reacts quickly, inject directly through the tool rather than a hose assembly.
6. Inject from the bottom up. Inject at the lowest port until material appears at the next port up, then cap and move to that port. Work efficiently — 103's fast reaction leaves less dwell time than 102.
7. Let it cure. 103 cures fast, typically under an hour depending on temperature. Allow full cure before removing ports and trimming the surface seal if desired.

Additional mechanical specs (shear, tensile, elongation) can be added from the 103 data sheet.

What size cracks is NextStar 103 used for?
103 is for wider non-structural poured concrete cracks from 3/16" to 1/2", and for void fill. For narrower cracks down to 1/32", use NextStar 102.

Does 103 need water injected first like 102?
No. Unlike 102, NextStar 103 self-reacts and does not require the crack to be pre-flushed with water.

Can 103 be used as a structural foam?
For void fill and compression resistance, yes — its higher density lets it stand in for a structural foam in those applications. For true structural crack repair that transfers load and fuses concrete, use NextStar 120 structural foam or an epoxy.

Is 103 still watertight if the surface skin is cut?
Yes. 103 is a true closed-cell foam, so each cell stays sealed even if you cut or open the cured surface skin — it does not wick water the way open-cell foams do.

Can I use a feed hose with 103?
No. Because of 103's fast reaction time, inject directly through the dual cartridge tool rather than a hose assembly.

What comes in a NextStar 103 tube set?
Each dual 600ml tube set (two 300ml cartridges) ships with the retaining nut and a static mixer included. The 3/8 x 24 mixer is recommended for 103.