PLA prints beautifully but fails under load, heat, and UV. When engineers move beyond prototyping to functional hardware, the choice between PETG, nylon (PA12), and polycarbonate (PC) determines whether a part survives in service. At Layer X we process all three daily for industrial customers in Ahmedabad and across India. Here is our honest, application-focused comparison.
PETG (Polyethylene Terephthalate Glycol)
PETG is the workhorse engineering polymer. It is easier to print reliably than nylon or PC, has excellent chemical resistance to acids, alkalis, and many solvents, and is FDA-compliant for food-contact applications. Its glass transition temperature of 80°C makes it suitable for most indoor applications but problematic in engine bays or outdoor environments in Indian summers.
| Property | PETG |
|---|---|
| Tensile strength | 50–55 MPa |
| Heat deflection temperature | 70–80°C |
| Impact resistance | Medium-high |
| Chemical resistance | Excellent (most acids, alkalis) |
| Moisture absorption | Low (0.1–0.2%) |
| Price (at Layer X) | ₹350–600/part (small bracket) |
Best for: Medical device housings (FDA compliant grades), food processing equipment guards, chemical storage brackets, transparent or translucent enclosures, water-contact components.
Avoid when: Operating temperature exceeds 70°C, part is exposed to prolonged outdoor UV, or high stiffness is required (PETG is relatively flexible for an engineering plastic).
PA12 Nylon (Polyamide 12)
PA12 SLS nylon is the benchmark for functional 3D printed polymer parts. It is the material Layer X ships in the highest volume for end-use production. Isotropic mechanical properties (no weak Z-axis), outstanding fatigue resistance, and a geometry-freedom that no other polymer process matches make PA12 the default choice for complex functional parts.
| Property | PA12 (SLS) |
|---|---|
| Tensile strength | 45–52 MPa |
| Heat deflection temperature | 175°C (0.45 MPa load) |
| Impact resistance | Very high (Charpy 4–8 kJ/m²) |
| Chemical resistance | Good (hydrocarbons, weak acids) |
| Moisture absorption | Medium (0.9–1.2% equilibrium) |
| Price (at Layer X) | ₹500–1,200/part (small bracket) |
Best for: Production hardware, duct and fluid-system components, gear and bearing housings, complex snap-fit assemblies, wearable device enclosures, all geometries with internal channels.
Avoid when: Part is immersed in water long-term (nylon absorbs moisture and swells), UV exposure without UV-stabilised coating, or when PETG chemical resistance is specifically required.
Polycarbonate (PC)
Polycarbonate is the toughest FDM engineering polymer and the only common 3D printing material that remains functional above 120°C. PC is difficult to print — it requires an enclosed printer, dry filament, and bed temperatures above 100°C. When printed correctly, PC parts have the highest impact strength of any common 3D printing thermoplastic and outstanding optical clarity (in natural grade).
| Property | PC (FDM) |
|---|---|
| Tensile strength | 55–70 MPa |
| Heat deflection temperature | 130–140°C |
| Impact resistance | Outstanding (Izod 850 J/m) |
| Chemical resistance | Poor (hydrocarbons, acetone attack PC) |
| Moisture absorption | Low (0.15–0.35%) |
| Price (at Layer X) | ₹600–1,400/part (small bracket) |
Best for: Electrical enclosures, automotive under-bonnet components, lighting housings, transparent guards and shields, sterilisable medical housings (PC withstands autoclave cycles), welding fixtures.
Avoid when: Chemical exposure to hydrocarbons, ketones, or aromatic solvents, or for complex geometry (FDM support removal is difficult in PC).
Quick Decision Matrix
| Requirement | Choose |
|---|---|
| Temperature > 120°C | PC, or PEEK for >200°C |
| Temperature 80–120°C | PC or PA12 |
| Chemical resistance | PETG (acids/alkalis) or PA12 (hydrocarbons) |
| Complex geometry, any direction | PA12 SLS |
| Maximum impact resistance | PC |
| Food contact / FDA | PETG (FDA-compliant grade) |
| Lowest cost | PETG |
Browse Layer X material options or request samples of all three materials for application testing.