We machine custom threaded components — internal, external, single-start, multi-start, tapered, and specialty threads — in production volumes from prototypes to millions of parts. For 75+ years, OEMs across fluid power, instrumentation, heavy equipment, and industrial hardware have relied on us for threads that seal tight, fit right, and hold up. ISO 9001 certified, U.S.-made, and machined within ±0.005" tolerances.
We machine threads to all common standards and many specialty forms. Whether you need standard unified threads for general assembly or precision ACME threads for motion control, we have the tooling and process controls to hold pitch, lead, and form to your specifications.
Standard thread forms:UNC and UNF (Unified National Coarse/Fine), Metric (M-series), ACME and Stub ACME, NPT and NPTF (tapered pipe threads), BSPP and BSPT (British Standard), Buttress threads.
Specialty capabilities:Multi-start threads for quick-engagement applications, Left-hand threads, Miniature threads (down to 0-80 / M1), Long-length threads on shafts and rods, Thread milling for non-round or interrupted features, Single-point threading for custom pitch and form requirements.
We use a variety of machining processes to manufacture custom precision parts with internal and external threads.
• Custom fasteners: Bolts, screws, studs, and nuts machined to non-standard dimensions or specialty materials.
• Threaded shafts and rods: Long-length external threads, lead screws, and drive rods for motion and positioning systems.
• Standoffs, spacers, and inserts: Internally and externally threaded components for assembly and panel mounting.
• Threaded bushings and adapters: Transition pieces that connect mismatched thread standards or sizes.
• Valve stems and plugs: Precision threads for reliable sealing and actuation in fluid and gas systems.
• Adjustable and locking components: Set screws, jam nuts, adjusting screws, and fine-pitch locking mechanisms.
If your part isn't listed, contact us to discuss your unique requirements.
Spex is equipped to be your comprehensive machining partner. Our manufacturing capabilities and just-in-time inventory management solutions are built to scale with your needs.
• CNC Turning: Our primary method for external and internal threads on cylindrical parts. Single-point threading gives us full control over thread form, pitch, and depth — essential for non-standard or custom thread profiles. Live tooling adds cross-drilled holes and flats without a second setup.
• Swiss Screw Machining: Ideal for small-diameter threaded parts (up to 7/8") where concentricity between the thread and other features must be held within tight tolerances. High efficiency for production runs.
• Multi-Spindle Machining: Our most cost-effective option for high-volume threaded components. Multiple tools cut simultaneously, producing finished threaded parts at rates standard CNC can't match.
• CNC Milling: Used when threads must be cut into non-cylindrical parts, interrupted surfaces, or when a specific thread form can't be achieved with standard turning. Also used for large-diameter internal threads.
Learn more about our manufacturing capabilities.
In addition to our machining, we offer secondary processes like plating, engraving, anodizing, and heat treating. Our manufacturing capabilities and just-in-time inventory management solutions are built to scale with your needs.
Selecting the right material is crucial for the performance and durability of your custom threaded parts. Our team has extensive experience machining a diverse array of materials, ensuring optimal machinability and dimensional accuracy
• Stainless Steels: 303, 304, 316, 416 (for corrosion resistance and strength)
• Aluminum Alloys: 6061, 7075 (for lightweight strength and machinability)
• Brass & Bronze: (for excellent machinability, conductivity, and corrosion resistance)
• Carbon & Alloy Steels: 1018, 4140 (for high strength and wear resistance)
View all the materials we use for machined parts.
Our quality control team inspects parts throughout the production process to ensure they meet customer specifications. Our ISO 9001:2015 certified quality system maintains consistent standards from first article to production runs. Documentation includes material traceability, inspection reports, and First Article Inspection Reports (FAIR) based on customer requirements.
If you have a question about our secondary manufacturing services, or want to request a quote, reach out to our team by filling out the form or email sales@spex1.com.
We'd love to hear from you!
Scalable production
Short lead times
Fair prices
ISO-9001 certified
Secondary processes
Range of materials
On-time delivery
75+ years in business
Advanced CNC machining
Rapid prototyping
Exact tolerances depend on the material, machining process, and part dimensions. Spex consistently holds exceptionally tight tolerances on custom threaded parts. Most parts can be consistently held within ∓0.005 inches.
Swiss machines handle miniature threads down to 0-80 (M1 metric) on parts as small as 7/8" diameter. Our CNC lathes can thread parts up to 20" diameter. For thread lengths, we can produce long-run threads on shafts and rods — contact us with your specific dimensions.
Quality and accuracy are fundamental at Spex. Our ISO:9001:2015 certified quality management system guides every step. We use detailed inspection processes and advanced measurement equipment to verify thread pitch, diameter, lead, and form, guaranteeing parts meet precise specifications.
Yes, we can produce custom threaded parts with various specific surface finishes and manage coating requirements. We partner with trusted providers for processes like anodizing, plating, and passivation, ensuring your components meet all functional and cosmetic specifications.
To provide an accurate quote, please provide detailed engineering drawings (including dimensions, tolerances, and thread specifications), the required material type, and the estimated order quantity. This information helps us streamline the quoting process.
