LE Phenolic Rod — Diameters, Lengths & Tolerances
LE phenolic rod is round bar stock produced from NEMA Grade LE linen phenolic laminate: fine-weave cotton (linen) fabric layers impregnated with phenolic resin and compression-molded under heat and pressure. Ready Plastics stocks LE phenolic rod as precision starting stock for electrical terminal posts, bushings, switchgear components, and insulating standoffs where a finer fabric weave delivers a smoother surface finish and enhanced dielectric performance compared to canvas grades. NEMA LI-1 governs Grade LE.
At a glance:
- Diameter range: 0.125" to 6.0"
- Standard length: 48" (4 ft) per piece
- OD tolerance: typically ±0.010" on stock rod
- Material: NEMA Grade LE — fine-weave cotton-fabric phenolic laminate (NEMA LI-1)
- Production method: Compression-molded thermoset
- Color: Natural tan
Standard Diameter Table
LE phenolic rod is stocked in the following standard diameters:
| Diameter | Standard Length | Notes |
|---|---|---|
| 0.125" (1/8") | 48" | Fine-feature insulator stock |
| 0.250" (1/4") | 48" | Precision standoff stock |
| 0.500" (1/2") | 48" | Terminal post and bushing blanks |
| 0.750" (3/4") | 48" | Switchgear component stock |
| 1.000" (1") | 48" | General electrical insulator |
| 1.500" (1-1/2") | 48" | Larger precision insulator blanks |
| 2.000" (2") | 48" | Heavy-duty bushing stock |
| 3.000" (3") | 48" | Large-diameter electrical insulator |
Cut-to-length available on all diameters; minimum order is one piece.
Mechanical & Electrical Properties
LE phenolic rod carries the full NEMA Grade LE property set per NEMA LI-1:
| Property | Value |
|---|---|
| Tensile strength | 36,000 psi (245 MPa) |
| Flexural strength (LW, 0.125") | 18,000 psi (120 MPa) |
| Compressive strength | 13,000 psi (89 MPa) |
| Shear strength | 13,500 psi (93 MPa) |
| Bond strength | 1,900 psi (13 MPa) |
| M-scale hardness | 100 |
| Izod impact strength at 49 °C (LW) | 1.35 ft·lb/in |
| Specific gravity | 1.34 |
| Water absorption (24 hr) | 1.8% |
| Flammability | UL 94HB |
| Max. operating temperature | 255 °F (125 °C) |
The fine linen weave results in lower water absorption (1.8% vs. 2.0% for CE) and higher flexural strength (18,000 psi vs. 17,000 psi), making LE the preferred grade for demanding electrical insulation.
Typical Applications
- Terminal boards and bus-bar posts — High dielectric strength and smooth surface enable reliable conductor isolation in switchgear and distribution panels
- Precision bushings and bearings — Fine weave produces a consistent bore surface after turning, supporting close-fit insulating sleeve applications
- Switchgear insulators and arc barriers — LE's superior dielectric performance suits live-contact separation in medium-voltage switching equipment
- Coil formers and bobbin stock — Smooth exterior and dimensional stability simplify wire winding on turned LE rod sections
- Relay and contactor components — Low water absorption (1.8%) maintains stable dielectric properties in humid panel environments
- Precision machined electrical hardware — Terminal blocks, standoffs, and threaded insulators for industrial and utility electrical systems
Machining LE Phenolic Rod
LE phenolic rod machines to excellent surface finishes on conventional lathes with sharp carbide tooling. The fine linen weave produces a smoother bore and OD finish than coarser canvas grades — important for components with press-fit or slip-fit tolerances. Use light finishing passes at moderate speed to achieve finishes suitable for precision insulator fits. Threads tap cleanly with standard HSS or carbide taps; no thread inserts required for common electrical hardware sizes. Phenolic dust is abrasive — use dust extraction throughout.
Related
- LE Phenolic Grade Line Card
- LE Phenolic Sheet — flat stock for precision terminal boards and panel insulators
- LE Phenolic Tube — hollow section for insulating sleeves and conduit liners
- CE Phenolic Rod — coarse canvas grade for general-purpose mechanical and electrical insulation