Custom Machined Standoffs
Standoffs and spacers are among the most frequently ordered machined plastic parts in electrical and electronic assemblies. They establish a precise gap between components, provide mechanical support, and — when made from the right dielectric material — provide electrical isolation that no metal standoff can offer. Federal Materials machines plastic and thermoset standoffs to any dimension, in any quantity, from customer prints.
We machine standoffs in hex and round profiles, in threaded (male or female) and smooth-bore configurations, across the full range of dielectric-grade materials: G10, FR4, phenolic (XX, CE), PEEK, and Delrin. Short lengths for PCB support; long lengths for power switchgear; every dimension in between.
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Request a Quote →Standoff Types We Machine
- Hex standoffs with female-female threads — PCB, panel, and enclosure mounting
- Hex standoffs with male-female threads — stacking and pass-through configurations
- Round standoffs / spacer sleeves — smooth bore or through-threaded
- Threaded rod standoffs — male threads both ends, custom length
- Solid spacers — unthreaded, any OD, any length
- Large-bore switchgear standoffs — high-voltage bus bar support and phase separation
- Custom-profile standoffs — stepped OD, hex-to-round, shoulder features per print
- Long standoffs — up to 24" lengths from rod stock
Material Selection Guide
| Material | Dielectric strength | Temp limit | Best for |
|---|---|---|---|
| G10 | 500 V/mil | 285°F | PCB standoffs, switchgear spacers |
| FR4 | 500 V/mil | 285°F | UL-listed assemblies |
| XX Phenolic | 450 V/mil | 220°F | High-volume production, switchgear |
| CE Phenolic | 450 V/mil | 220°F | Better impact resistance |
| Delrin | 500 V/mil | 220°F | Mechanical spacers, light electrical |
| PEEK | 480 V/mil | 480°F | High-temp, chemical-resistant |
| PTFE | 500 V/mil | 500°F | Chemical service, low contamination |
Typical Tolerances
| Dimension type | Production tolerance |
|---|---|
| Length | ±0.005" standard; ±0.001" on request |
| OD (turned) | ±0.001" standard |
| Bore / thread | 2B/3B class per print |
| Across flats (hex) | ±0.003" |
| Concentricity | 0.002" TIR |
Thread options: UNC, UNF, metric (specify on print). Non-standard thread forms on request.
Finish Options
| Finish | Description |
|---|---|
| As-machined | Standard for fiberglass and thermoplastic standoffs |
| Hot oil dip | Standard for phenolic standoffs — protects threads and bores from moisture wicking |
| Chamfered thread entries | Standard; eases assembly |
| No plating | Standoffs must remain non-conductive — no metallic surface treatment |
Standard Turnaround
| Stage | Lead time |
|---|---|
| Quote response | Same business day |
| Prototype / first article (1–25 pcs) | 2–5 business days |
| Short run (25–500 pcs) | 5–10 business days |
| Production run (500+ pcs) | 10–15 business days |
Standoffs are high-volume-friendly: once threaded and faced, production rates are fast. Volume pricing improves substantially at 100+ pieces.
Materials We Stock (Standoff Stock Shapes)
| Material | Forms | Notes |
|---|---|---|
| G10 | Rod, hex bar | NEMA GP03; ¼" – 6" dia rod |
| FR4 | Rod | NEMA FR4; UL94 V-0 |
| XX Phenolic | Rod | NEMA LI-1 XX; ¼" – 6" dia |
| CE Phenolic | Rod | NEMA LI-1 CE |
| Delrin | Rod | Delrin 150; ¼" – 10" dia |
| PEEK | Rod | Unfilled and glass-filled |
| PTFE | Rod | ASTM D4894 |
Hex bar stock is available for G10 and some phenolic grades — reduces machining time on hex standoffs. Call for current availability.
Quality & Inspection
- Dimensional inspection — length, OD, thread, across-flats on every order
- Thread gauge inspection — 2B/3B go/no-go on all threaded standoffs
- Dielectric testing — available for high-voltage applications (specify)
- Material C of C — lot traceability, NEMA or ASTM spec reference
- Visual inspection — thread condition, bore, surface, edge chamfer
Get a quote on
Request a Quote →More Related Guides
- PEEK Machined Parts — high-temp standoffs
- Delrin Machined Parts — economical mechanical spacers
- Custom Machined Insulators
- CNC Turning Thermoset Rod
- G10 vs. FR4 — standoff material choice