Materials
Materials library
Properties, grades, and design notes for the 25 materials we mold, machine, print, and form most often. Every entry gives real datasheet values and the reason you would choose it over the alternative.
14 materials
Thermoplastics
ABS
The default enclosure plastic. Tough, easy to mold, easy to finish.
Polycarbonate
Transparent, and the toughest common engineering thermoplastic.
Polypropylene
Cheap, chemically inert, and the only common plastic with a real living hinge.
HDPE
Low friction, chemically inert, and tough at low temperature.
Nylon (PA)
Strong, tough, wear resistant, and it absorbs water.
Acetal (POM)
The precision plastic. Stiff, slippery, and dimensionally stable.
Acrylic (PMMA)
The clearest common plastic, and the most scratch resistant.
PETG
Clear, tough, easy to form, and safe for food contact.
PBT
The connector plastic. Stable, insulating, and it barely takes up water.
PC/ABS
PC toughness and heat, ABS processing and finish.
PEEK
The high performance polymer. Metal-adjacent properties, metal-adjacent price.
PEI (Ultem)
Amber, transparent, flame retardant, and stable to 170 °C.
Polystyrene (HIPS)
The cheapest molding plastic. Rigid, clear in GPPS, tough in HIPS.
PLA
The default printing polymer. Accurate, easy, and not for service parts.
| Material | Full name | Tensile strength | Processes |
|---|---|---|---|
| ABS | Acrylonitrile butadiene styrene | 40–45 MPa | Molding, CNC, 3D printing |
| Polycarbonate | Polycarbonate (PC) | 60–70 MPa | Molding, CNC, 3D printing |
| Polypropylene | Polypropylene (PP) | 30–35 MPa | Molding, CNC |
| HDPE | High density polyethylene | 22–31 MPa | Molding, CNC |
| Nylon (PA) | Polyamide 6 and 6/6 | 70–85 MPa (dry) | Molding, CNC, 3D printing |
| Acetal (POM) | Polyoxymethylene, Delrin | 62–70 MPa | Molding, CNC |
| Acrylic (PMMA) | Polymethyl methacrylate | 70–75 MPa | Molding, CNC |
| PETG | Glycol-modified polyethylene terephthalate | 50 MPa | Molding, 3D printing |
| PBT | Polybutylene terephthalate | 55 MPa (135 GF30) | Molding |
| PC/ABS | Polycarbonate / ABS alloy | 55 MPa | Molding, 3D printing |
| PEEK | Polyether ether ketone | 95–100 MPa | Molding, CNC, 3D printing |
| PEI (Ultem) | Polyetherimide | 105 MPa | Molding, CNC, 3D printing |
| Polystyrene (HIPS) | General purpose and high impact polystyrene | 45 MPa (GPPS), 25 MPa (HIPS) | Molding |
| PLA | Polylactic acid | 50–60 MPa | 3D printing |
3 materials
Elastomers
TPU
A rubber you can injection mold and print.
TPE (SEBS)
The soft-touch overmold material. Very soft, easy to bond to ABS and PP.
Silicone (LSR)
Wide temperature range, biocompatible, and molded as a thermoset.
| Material | Full name | Hardness | Processes |
|---|---|---|---|
| TPU | Thermoplastic polyurethane | 70 Shore A – 75 Shore D | Molding, 3D printing |
| TPE (SEBS) | Styrenic thermoplastic elastomer | 20–90 Shore A | Molding |
| Silicone (LSR) | Liquid silicone rubber | 10–80 Shore A | Molding |
8 materials
Metals
Aluminum 6061
The default machining alloy. Strong enough, light, and it cuts fast.
Aluminum 7075
Aerospace aluminum. Near steel strength, but it does not weld or corrode well.
Aluminum 5052
The sheet metal aluminum. Forms tightly and resists salt.
Stainless 304
The general purpose stainless. Corrosion resistant, hygienic, and formable.
Stainless 316L
Marine and medical stainless. Molybdenum for chloride resistance.
Mild steel (CRCA)
The cheapest formable sheet. Needs a coating.
Brass C36000
The fastest metal to machine, and it conducts.
Titanium Grade 5
Steel strength at half the weight, fully biocompatible, hard to cut.
| Material | Full name | Tensile strength | Processes |
|---|---|---|---|
| Aluminum 6061 | Aluminum 6061-T6 | 310 MPa (T6) | CNC, Sheet metal |
| Aluminum 7075 | Aluminum 7075-T6 | 572 MPa (T6) | CNC |
| Aluminum 5052 | Aluminum 5052-H32 | 228 MPa (H32) | Sheet metal |
| Stainless 304 | Stainless steel 304 / 1.4301 | 515 MPa | CNC, Sheet metal |
| Stainless 316L | Stainless steel 316L / 1.4404 | 485 MPa | CNC, Sheet metal |
| Mild steel (CRCA) | Cold rolled close annealed steel, IS 513 / DC01 | 270–350 MPa | Sheet metal, CNC |
| Brass C36000 | Free machining brass, C36000 / CuZn39Pb3 | 340–470 MPa | CNC |
| Titanium Grade 5 | Ti-6Al-4V, Grade 5 | 950 MPa | CNC, 3D printing |
How to use this
Material choice is usually decided by one binding constraint: a service temperature, a chemical, a load, a certification, or a cost target. Find the constraint first, then read the alternatives section on the candidate page, it names what to move to when the first choice fails.
Values here are typical published figures for unfilled grades at 23 °C. They are for narrowing the field, not for design calculation. Confirm against the supplier datasheet for the exact grade before release.
Not sure yet?
Send the part and the environment it works in. We will come back with two or three candidate materials, what each would cost, and what each would compromise.