PlasticsWhat is PA 6 nylon and which one should you choose? Nylon M, SL, XL, HS and AL
Nylon is the most widely used engineering plastic in industry: lightweight, strong, with excellent sliding properties and very easy to machine. In this guide we explain what cast nylon PA 6 is, why it can replace bronze and aluminum in bushings, rollers, pulleys and gears, and how the five grades we carry at NAT MAC differ.
What is nylon PA 6?
Nylon PA 6 is an engineering polyamide made by casting: caprolactam is polymerized directly inside the mold, which produces semi-finished products with low internal stresses and in large dimensions. That is why it is identified by the designations PA 6 C or PA 6 G (cast polyamide 6, DIN/EN 15860 standard) and should not be confused with nylon 6/6 or PA 66.
It is a lightweight, tough material with high mechanical strength, impact resistance and abrasion resistance, and excellent sliding properties. It machines and welds easily, and resists hydrocarbons, alkalis and oils. Its weak point is that it absorbs moisture (about 2.5%), which must be considered in very tight-tolerance parts.
Why choose this family?
Compared with metal parts or other plastics, it offers several advantages:
| Advantage | What does it mean? |
|---|---|
| Replaces bronze and aluminum | Reduces weight, noise and maintenance in parts subject to friction, motion and load |
| Excellent sliding properties | Low coefficient of friction and good wear resistance in bushings, guides and rollers |
| High mechanical strength and impact resistance | Yield strength of 70 to 82 MPa depending on the grade, with very good toughness |
| Easy to machine | Turns, mills, and drills with conventional tools; stress-free semi-finished stock |
| Large sizes | Round bars up to 17" and plates up to 6" thick thanks to the casting process |
The grades we carry
These are the variants available at NAT MAC and what each one is best for:
| Grade | What sets it apart? | Ideal for |
|---|---|---|
| Nylon M natural | Basic grade with no fillers; white or black | General-purpose sliding parts, rollers, pulleys, bushings and gears |
| Nylon SL black | Molybdenum disulfide: higher surface hardness and lower friction; black | Bushings and bearings with heavy load, continuous wear or limited lubrication |
| Nylon HS blue | UV and heat-aging additives; blue | Parts exposed to high temperature or the elements |
| Nylon AL red | Integrated solid and liquid lubricants; friction ≈ 0.08; red | High-load, high-speed bushings and bearings with little or no external lubrication |
| Nylon XL green | Built-in lubricating oil that does not migrate or dry out | Rollers, pulleys and guides that run with little lubrication and need a long service life |
Technical properties
Reference values taken from our data sheets; they may vary depending on manufacturing and application conditions:
| Property | Natural | With MoS₂ | Stabilized blue | Self-lubricating | With oil |
|---|---|---|---|---|---|
| Density | 1.15 g/cm³ | 1.15 g/cm³ | 1.15 g/cm³ | 1.14 g/cm³ | 1.14 g/cm³ |
| Yield strength | 75 MPa | 82 MPa | 75 MPa | 70 MPa | 70 MPa |
| Modulus of elasticity | 3,400 MPa | 3,500 MPa | 3,700 MPa | 3,400 MPa | 3,300 MPa |
| Hardness | 83 Shore D | 83 Shore D | 82 Shore D | 82 Shore D | 82 Shore D |
| Continuous service temp. | −40 a 110 °C | −40 a 110 °C | −40 a 120 °C | −40 a 110 °C | −40 a 110 °C |
| Water absorption | 2.5 % | 2.5 % | 2.5 % | 2.0 % | 2.0 % |
Available package sizes
| Material | Available forms | Colors | Supply |
|---|---|---|---|
| Nylon M natural | Round bars 3/8" – 17" (9.5 mm – 432 mm) · Plates 1/4" – 6" (6.35 mm – 152 mm) · Square bars 1" – 6" (25.4 mm – 152 mm) · Hollow bars 2½"×1½" – 12"×6" (63.5×38 – 305×152 mm) | Natural/white, Black | Cast |
| Nylon SL black | Round bars 3/8" – 17" (9.5 mm – 432 mm) · Plates 1/4" – 6" (6.35 mm – 152 mm) · Square bars 1" – 6" (25.4 mm – 152 mm) · Hollow bars 2½" × 1½" – 12" × 6" (63.5 × 38 mm – 305 × 152 mm) | Black | Cast |
| Nylon HS blue | Round bars 1" – 17" (25.4 mm – 432 mm) · Plates 1/4" – 4" (6.35 mm – 101.6 mm) | Blue | Cast |
| Nylon AL red | Plates 1/4" – 4" (6.35 mm – 101.6 mm) · Round bars Various diameters (On request) · Square bars Various sections (On request) | Red | Cast |
| Nylon XL green | Round bars 1" – 17" (25.4 mm – 432 mm) · Plates 1/4" – 4" (6.35 mm – 101.6 mm) | Green, Yellow | Cast |
If you need a particular size, tell us which one and we will gladly source it for you.
Where is it used?
Some of the most common applications of these materials in industry:
- Bushings and sleeves
- Industrial rollers
- Pulleys
- Gears
- Guides and sliding parts
- Wear plates
- Wheels and bogie components
- Components for lifting equipment
- Cable drums
- Star wheels for filling lines
- Worm screws
- Load-bearing replacement parts
How to choose?
- General use and price: natural Nylon M, the most versatile choice for rollers, pulleys, bushings and gears.
- High load and continuous wear: black Nylon SL, for its higher surface hardness and lower friction.
- Heat or outdoor exposure: blue Nylon HS, protected against UV rays and thermal aging.
- Little or no lubrication: red Nylon AL (coefficient of friction ≈ 0.08) or green Nylon XL, depending on the load and operating speed.
In summary
- Cast PA 6 nylon is lightweight, strong, slides well, and is easy to machine; it replaces bronze and aluminum in many parts
- Made by casting, which yields large, stress-free semi-finished products (bars up to 17" and plates up to 6")
- We carry five grades: natural, with MoS₂, heat-stabilized blue, self-lubricating and oil-filled
- The right grade depends on the load, speed, temperature and lubrication available
Why buy your engineering plastics at NAT MAC?
We have more than 54 years of experience in the industry and ISO 9001 certified quality. We carry all ten families of engineering plastics (nylon, polyethylene, acetal, Teflon, polycarbonate, PEEK, PETG, PET, polypropylene and thermosets), each with its own data sheet, and we help you choose the right material for your part, your load and your working environment.
- Material cut to the size you need
- Data sheets with verified properties for each grade
- Advice on choosing the right plastic for your load, temperature and environment
- Stock in bars, plates and bushings with delivery throughout Mexico
- Backed by ISO 9001 certified quality
Tell us what part you'll make, the conditions it operates in and the sizes you need, and we'll recommend the right material. Request your free quote.
Sources: NAT MAC Engineering Plastics data sheets and catalog; TecnoQuim (material data sheets); ISO 527-1, Determination of tensile properties; ISO 868, Shore hardness.



