Body and sheet metal
Seam sealers for body panels, doors and container joints — sandable, paintable, four colours.
Choosing one
KA540 is a sealer, not a structural adhesive. The 600% elongation and 2.5 MPa are chosen so the bead follows a flexing panel and still sands and takes paint. Where the OEM drawing calls for a panel bond, the product class is different and the bond line is 0.2–0.5 mm, so do not substitute.
Where it goes wrong
The two rework cases that cost most are a bead applied over e-coat without scuffing, and a sealer sanded before it has cured. The first lifts at the edge after paint; the second tears and leaves a step in the finish. Both are surface and schedule, not product.
The 2.5 MPa and the 600% are a pair. Read alone, 2.5 MPa looks weak next to a structural adhesive at 20 MPa; read as a sealer, it is the point: the bead has to move with the panel and still sand and take paint.
Decision table
| If | Then | Because |
|---|---|---|
| The seam will be sanded and painted | KA540 | 600% elongation, sandable, takes a topcoat |
| The OEM drawing calls for a panel bond | not this class | a 0.2–0.5 mm bond line needs a structural adhesive |
| Container or trailer seam | KA540 or KAM921 | movement in the joint versus UV on the outside |
| Interior floor seam | KA540 | flexible under foot traffic and paintable |
Read before you specify
Other families
- Automotive glass bonding — Windscreen, side and rear glass adhesives — 310 ml cartridges, sausages and 200 L barrels.
- Construction joints — Concrete, tunnel and drainage sealants — 550–615% elongation, elastic recovery up to 80%.
- Industrial and STP — Silyl-terminated polymer sealant for metal, plastic and glass — primerless and paintable.
- Wood and glulam — One-component PUR for engineered timber, glulam beams and sandwich panels.
- Activators and primers — Surface preparation that decides whether the bead holds: K-901 activator, K-801 primer.