Cyanoacrylate (CA) Glue and Accelerator
Comprehensive technical specification for cyanoacrylate (CA) adhesive and accelerator, covering properties, sizing, machinability, defects, and handling for Canadian industrial fabrication, woodworking, and machining operations.
Material Overview & Common Uses
Cyanoacrylate (CA) glue is a fast-curing, single-component adhesive that polymerizes rapidly in the presence of moisture. In Canadian fabrication and woodworking shops, CA glue is prized for its ability to bond non-porous and porous materials with minimal clamping. Common uses include: temporary fixturing for CNC machining, bonding jigs and fixtures, repairing small wood defects (e.g., knots, cracks), attaching veneers, and assembling prototypes. Accelerator (typically a solvent-based aerosol or liquid containing a tertiary amine or other catalyst) is used to speed cure times from seconds to instant, enabling high-throughput operations. CA glue is available in various viscosities (thin, medium, thick, gel) to suit different gap-filling and wicking requirements. Typical Canadian shop applications include bonding hardwoods (maple, oak, walnut), softwoods (pine, cedar), metals (aluminum, steel), plastics (ABS, acrylic), and rubber. CA glue is also used in model making, musical instrument repair, and light structural assembly where speed is critical.
Core Technical Properties & Sizing
| Property | Value / Specification |
|---|---|
| Viscosity Range | 2–5000 cP (thin: 2–10 cP, medium: 50–200 cP, thick: 500–1500 cP, gel: 2000–5000 cP) at 25°C |
| Cure Time | 5–60 seconds (without accelerator); <1 second with accelerator (dependent on humidity, temperature, and material porosity) |
| Shear Strength | 1500–3000 psi (10–20 MPa) on steel-to-steel bonds (ASTM D1002) |
| Temperature Resistance | -40°C to +80°C continuous; up to +120°C intermittent |
| Shelf Life | 12 months from date of manufacture when stored unopened at 2–8°C (refrigerated). Opened bottles: 3–6 months if kept sealed and refrigerated |
| Standard Packaging | 20 g, 50 g, 100 g, 500 g, 1 kg bottles; accelerator in 100 mL, 200 mL, 500 mL aerosol cans or pump spray bottles |
| Canadian Stock Sizes | Commonly available in 20 g and 50 g bottles for shop use; 1 kg bulk for high-volume operations. Accelerator typically in 200 mL aerosol |
| Color | Clear (water-white) to slightly yellow; accelerator is clear liquid or aerosol propellant |
| Flash Point | CA glue: >80°C (low flammability); accelerator: typically -20°C to +40°C (highly flammable – Class 1A or 1B) |
| VOC Content | CA glue: <5 g/L; accelerator: up to 100% VOC (solvent-based) |
| Specific Gravity | CA glue: 1.05–1.10; accelerator: 0.75–0.85 (solvent dependent) |
Machinability, Tooling & Feeds
CA glue is not machined directly but is used to bond workpieces that are subsequently machined. The following parameters are recommended for assemblies bonded with CA glue.
| Parameter | Recommendation |
|---|---|
| CNC Routing (Hardwood) | 12,000–18,000 RPM spindle speed, 100–200 IPM feed rate, 0.010–0.020 in depth of cut per pass |
| CNC Routing (Metal) | 8,000–12,000 RPM spindle speed, 30–60 IPM feed rate, 0.005–0.010 in depth of cut per pass |
| Tooling | Sharp carbide tooling (e.g., 2-flute upcut spiral for wood) to avoid heat buildup |
| Heat Management | Use coolant mist or air blast to clear chips. Avoid heat buildup that can soften the adhesive |
| Tool Loading | CA glue can cause tool loading if bond line is thick. Clean tools with acetone or CA debonder immediately |
| Sanding | 80–120 grit for initial removal of CA-filled defects, then progress to 220 grit. CA glue sands cleanly but can clog paper if not fully cured |
| Drilling | HSS or carbide drill bits at 2000–3000 RPM with pecking to clear chips |
| Temperature Limit | Not recommended for high-temperature machining (e.g., grinding) as it degrades above 120°C |
Common Defects & Quality Control
| Defect | Description | Mitigation |
|---|---|---|
| Bloom / Frosting | White residue on surfaces due to outgassing of cyanoacrylate vapors | Use accelerator sparingly, improve ventilation, or use low-odor CA formulations |
| Crazing | Fine cracks in plastic substrates (e.g., acrylic, polycarbonate) caused by solvent attack | Use CA formulations specifically for plastics (e.g., 'plastic bonder') or apply accelerator first |
| Stringing | Thin filaments of glue forming when opening bottle or applying | Use gel or thick CA for vertical surfaces; clean nozzle with acetone |
| Premature Curing | Glue hardens in bottle or on applicator tip due to moisture ingress | Store with desiccant cap, keep bottle upright, and use within shelf life |
| Accelerator Overspray | Causes rapid curing on unintended surfaces, leading to poor bond strength | Use precision spray nozzle or apply with brush |
| Bond Line Brittleness | CA glue becomes brittle under impact or vibration | Use rubber-toughened CA for flexible bonds |
| Poor Adhesion | On oily or contaminated surfaces | Ensure surfaces are clean and dry. Perform peel test (ASTM D3167) or shear test (ASTM D1002) daily |
| Gelation | Thickening or gelling of CA glue if stored above 25°C | Check viscosity with a simple flow test (e.g., time to drip from a 20 mL syringe) |
Storage, Handling & Racking Guidelines
| Parameter | Requirement |
|---|---|
| Storage Temperature (CA) | 2–8°C (refrigerated). Do not freeze. |
| Storage Temperature (Accelerator) | Flammable liquids cabinet (NFPA Class I), away from heat, sparks, and open flames. |
| Orientation | Keep CA glue bottles upright to prevent leakage into cap threads. Use desiccant caps (silica gel) to absorb moisture. |
| Racking | Heavy-duty wire shelving (e.g., 18″ deep, 4–5 shelves) for 1 kg bulk bottles; bin racks or pegboard for 20–50 g bottles. Label with product name, viscosity, and expiry date. |
| Handling PPE | Nitrile gloves (CA glue bonds to latex instantly). Safety glasses and ventilation required (CA vapors can irritate eyes and respiratory tract). |
| Spill Procedure (CA) | Use CA debonder (acetone or proprietary solvent) and wipe immediately. |
| Spill Procedure (Accelerator) | Use absorbent pads and dispose as hazardous waste. |
| Inventory Management | Implement FIFO (first-in, first-out) using date codes. Use Ryxen SupplyGrid to set reorder points and auto-generate purchase orders. |
| Separation | Do not store CA glue near accelerators or other catalysts – accidental mixing can cause rapid exothermic reaction. |
| Regulatory | WHMIS 2015 classification – CA glue: Class 3 (flammable liquid); accelerator: Class 1A/1B flammable liquid. Ensure SDS sheets are accessible and staff trained. |