Hernon® Tuffbond 305 is a modified epoxy adhesive with a very fast room-temperature cure and very good moisture, chemical and heat resistance. It is specially formulated for rapid in-line assembly of loudspeakers, and is also recommended for bonding metals, wood and ceramics and for potting and encapsulating electrical and electronic components.
Typical Applications
- Loudspeaker voice coil to cone and pole piece to magnet bonding; bonding alnico magnets to bases
- Rapid-curing structural and electrical repair kits; laminates and gel coats
- Potting electronic boards; encapsulating electrical and electronic components
Typical Properties
- Part A epoxy (clear), Part B amine (light amber); mix ratio by weight 1:1
- Viscosity at 25 °C: A 10,000–16,000 cP, B 12,000–18,000 cP; specific gravity A 1.17, B 1.13
- Working life at 22 °C (100 g) 4–7 minutes
- Cured: hardness 80–90 Shore D; Tg 53 °C; thermal conductivity 0.522 W/(m·K)
Cure Speed and Shear Strength (ASTM D1002)
- Percentage of 24-hour strength on steel lap shears, at 22 °C: 30% after 2 hours, 40% after 4 hours, 100% after 24 hours; 100% after 2 hours at 45 °C
- 24 hours: grit-blasted aluminium 1000–2000 psi, grit-blasted steel 2000–3000 psi
Benefits and Storage
- Fast at room temperature (about 4 minutes); low shrinkage; 100% reactive, solvent-free; easy mix ratio; no fuming on gelation
- Not for pure oxygen or oxygen-rich systems; 7–29 °C (45–85 °F) in unopened containers
| Packing | 50 ML |