EPOCAST 1635
Harmonization Code : 3506.91.90.99 | Prepared glues and other prepared adhesives, not elsewhere specified or included; products suitable for use as glues or adhesives, put up for retail sale as glues or adhesives, not exceeding a net weight of 1 kg ; Adhesives based on polymers of headings 3901 to 3913 or on rubber; Other ; Other

Main features
- High-Temperature Composite Repair
- High-Strength Aluminum-Filled Epoxy
- Fatigue-Resistant Epoxy Syntactic
Product Description
EPOCAST® 1635 A/B is a two-component, aluminum-filled epoxy syntactic developed for refilling mis-drilled holes in composite parts. The high-viscosity system combines compressive strength with fatigue resistance under load at elevated temperature and is documented for performance at temperatures up to 177°C (350°F). It mixes at 100:23 by weight or 4:1 by volume and provides a gel time greater than 60 minutes for a 100 g mass at 25°C. The mixed material is blue-gray and may be hand mixed or dispensed from a 4:1 dual-barrel cartridge. EPOCAST® 1635 A/B is qualified to BMS 5-28, Type 31.
Key features
- Elevated-temperature strength: Provides 12 ksi compressive strength when tested at 177°C under either of the listed cure schedules.
- Controlled processing: Offers a gel time greater than 60 minutes at 25°C and supports manual mixing or 4:1 cartridge dispensing.
- Qualified repair material: Designed for refilling mis-drilled holes in composite parts and qualified to BMS 5-28, Type 31.
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Physical Properties
Additional Information
As-supplied / before-processing properties
Typical property and processing values for EPOCAST® 1635 A resin, 1635 B hardener, and the mixed system. Values are not guaranteed specifications unless specifically identified.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Appearance | Resin: blue-gray; hardener: amber-gray; mixed: blue-gray | — | Visual |
| Density | Resin: 1.8; hardener: 1.7; mixed: 1.8 | g/cm³ | ASTM D1622 at 25°C |
| Viscosity | Resin: >300,000; hardener: >50,000; mixed: >100,000 | cP | ASTM D2196 at 25°C |
| Mix ratio | 100:23 by weight; 4:1 by volume | Parts | 1635 A resin to 1635 B hardener |
| Gel time | >60 | min | 100 g mass at 25°C |
| Extrusion rate | >90 | g/min | 80 psig at 25°C |
| Typical cure cycle | 7 days at 25°C or gel at 25°C followed by 150 minutes at 93°C | — | Typical cure schedule |
| Shelf life | 18 | months | From date of manufacture in original sealed containers stored dry at 4–32°C |
After-processing / final-state properties
Typical cured-material results obtained using production batches and standard test methods. Values are representative laboratory data and do not constitute a product specification.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Compressive strength | 15 | ksi | ASTM D695; tested at 25°C after seven days at 25°C |
| Compressive strength | 12 | ksi | ASTM D695; tested at 177°C after seven days at 25°C |
| Compressive strength | 25 | ksi | ASTM D695; tested at 25°C after 2.5 hours at 93°C |
| Compressive strength | 12 | ksi | ASTM D695; tested at 177°C after 2.5 hours at 93°C |
| Fluid weight gain — deionized water | <1.0 | % | ASTM D543-87 |
| Fluid weight gain — Skydrol 500B hydraulic fluid | <1.0 | % | ASTM D543-87; BMS 3-11 Type IV, Class 1, Grade A fluid |
| Fluid weight gain — MIL-PRF-5606 hydraulic fluid | <1.0 | % | ASTM D543-87 |
| Fluid weight gain — TT-S-735 Type III reference fuel | <1.0 | % | ASTM D543-87 |





















