Precision CNC Machined Fasteners & Brass Threaded Inserts Manufacturer
CNC-machined fasteners and threaded inserts in brass and stainless steel – heat-set, ultrasonic, mold-in, self-tapping and knurled inserts, plus bolts, studs, nuts and pins – for OEMs worldwide.
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Amarex is a brass insert manufacturer and machined fastener exporter from India. We produce threaded inserts for plastics and metal – heat-set, ultrasonic, mold-in, self-tapping, knurled, helical and rotomolding types – plus CNC-machined bolts, studs, screws, nuts and pins in brass and stainless steel, threaded to UN, Metric, BSW and BSP standards and gauged 100% GO/NO-GO.
Machined Fasteners Components
Brass Threaded Inserts We Manufacture
Threaded inserts give plastic and soft-metal assemblies durable metal threads.
We machine every major insert type in free-machining brass, with knurling and grooving patterns matched to the installation method and pull-out/torque requirements.
Brass insert for plastic or metal: we advise insert type, knurl pattern and thread spec against your base material and loads.
| Insert type | Installation | Typical applications |
|---|---|---|
| Heat-set inserts | Thermal installation into thermoplastics | Electronics, consumer products, 3D-printed parts |
| Ultrasonic inserts | Ultrasonic welding into thermoplastics | High-volume plastic assemblies |
| Mold-in inserts | Placed in mould before injection/moulding | Injection-moulded engineering plastics |
| Self-tapping threaded inserts | Screwed into plastics or soft metals | Repairable threads in plastic and aluminium |
| Knurled / brass knurling inserts | Press-in or mould-in with knurl grip | General plastic assemblies |
| Helical inserts | Wire-thread reinforcement | Thread repair and high-cycle joints |
| Rotomolding inserts | Moulded into rotationally-moulded parts | Tanks, bins and large PE mouldings |
| Custom inserts | To customer drawing | Special geometries, threads and knurl patterns |
CNC Machined Fasteners – Bolts, Studs, Nuts & Pins
Beyond inserts, we machine the complete fastener range: bolts, studs, screws, nuts and pins in stainless steel and brass, standard or fully custom.
Thread capability spans UN-series (UNC, UNF, UNEF), Metric, BSW, BSP and BSPP, along with non-standard profiles to customer drawings. Every fastener is checked with calibrated GO/NO-GO gauges and precision measuring instruments.
- Bolts & studs – machined threads for critical assemblies
- Screws & nuts – standard and custom geometries
- Pins & special fasteners – to drawing, low or high volume
How We Manufacture Fasteners & Threaded Inserts
Threaded inserts are knurl-and-thread parts where the grip pattern matters as much as the thread.
Inserts and fasteners are CNC turned from free-machining brass and stainless bar, with knurl form, undercut and lead-in geometry set for the installation method the part is destined for.
Thread pitch diameter and knurl outside diameter are held to +/-0.01 mm (10 microns), since the interference between the knurl and the moulded boss is what carries the pull-out load.
Grade selection
Free-machining brass for inserts, stainless and brass for fasteners.
CNC turning
Body, knurl and undercut machined in one setup for concentricity.
Thread cutting
Internal and external threads cut and gauged in process.
Installation-specific detail
Lead-in and knurl form matched to heat-set, ultrasonic, mould-in or self-tapping use.
Finishing
Deburring and any specified plating, which is in our scope.
Inspection
Thread gauging and calibrated dimensional check before dispatch.
Fastener & Insert Manufacturing Process
An insert is only as good as its concentricity and its thread.
We turn the body, knurl and undercut in a single setup, then gauge every thread in process rather than sampling at the end of the run.
Free-machining brass for inserts, brass and stainless for fasteners
Body, knurl and undercut CNC turned in one setup for concentricity
Internal and external threads cut and gauged in process
Lead-in and knurl form matched to heat-set, ultrasonic or mould-in use
Why Choose Machined Brass Threaded Inserts
A moulded plastic boss gets one chance at a good thread.
Machined brass inserts are specified over self-tapping screws because they give a metal thread that survives repeated assembly, and because the knurl can be matched to the resin and the installation method rather than assumed.
Knurl and undercut matched to the installation - heat-set, ultrasonic, mould-in or self-tapping.
Repeatable pull-out and torque performance from controlled knurl geometry.
Threads cut and gauged in process, not sampled at the end of the run.
Brass for thermal installation, stainless where corrosion or strength governs.
Custom geometries, threads and knurl patterns produced to drawing without tooling cost.
Material traceability - test certificates with every batch, third-party NABL reports on request.
Industries We Supply Fasteners & Inserts To
Injection-moulded plastic assemblies
CNC machined mould-in and heat-set brass inserts
Electronics & consumer housings
CNC machined ultrasonic and knurled inserts
Automotive & industrial equipment
machined bolts, studs, nuts and pins
Electrical panels & enclosures
CNC machined self-tapping threaded inserts
Rotomoulded tanks & large mouldings
CNC machined rotomolding inserts and helical inserts
CNC Machining & Thread Capabilities
- Processes
CNC turning, threading, knurling, drilling, finishing
- Thread standards
UNC, UNF, UNEF, Metric, BSW, BSP, BSPP + non-standard profiles
- Inspection
Calibrated GO/NO-GO gauges, precision measuring instruments
- Materials
Free-machining brass, stainless steels
- Volumes
Large-scale production or specialised low-volume batches
- Custom work
Made to customer 2D/3D drawings and samples
- Quality
ISO-certified systems, material traceability
Quality Assurance
As an ISO 9001:2015 certified and modern CNC machine shop in India, we uphold global benchmarks while delivering cost-effective precision machining solutions. With RoHS & REACH compliance, we are a trusted machining partner for OEMs worldwide.
Why Amarex for CNC Machined Fasteners & Inserts
Amarex is an Indian manufacturer and exporter of precision CNC-machined components, with locations in Mumbai and Jamnagar.
As an ISO 9001:2015 certified (Mumbai office) fastener manufacturer we combine the full insert-type range with complete thread-standard coverage – one supplier for every threaded part on your BOM, from prototype to production.
- Every major insert type: heat-set, ultrasonic, mold-in, self-tapping, knurled, helical, rotomolding
- Full thread-standard coverage: UN-series, Metric, BSW, BSP, BSPP + custom
- 100% GO/NO-GO gauge verification
- Flexible volumes - large-scale or specialised low-volume batches
Meet the Expert Behind Fasteners & Inserts
Aryan Jain CEO
Frequently Asked Questions
We machine heat-set, ultrasonic, mold-in, self-tapping, knurled, helical and rotomolding inserts in free-machining brass, plus custom insert designs to drawing.
Yes. Brass inserts for plastic are our core insert product – heat-set, ultrasonic, mold-in and self-tapping types with knurl patterns matched to your base material and load requirements.
Yes. We machine self-tapping threaded inserts that cut their own threads in soft metals such as aluminium as well as plastics, providing durable repairable threads.
UN-series (UNC, UNF, UNEF), Metric, BSW, BSP and BSPP, plus non-standard profiles to customer drawings – all verified with calibrated GO/NO-GO gauges.
Yes. We manage large-scale production and specialised low-volume batches with the same gauging discipline and documentation.
Yes. Material test certificates and dimensional inspection reports ship with every batch.
Get a quote for fasteners & threaded inserts
Send us your drawings, thread specs or insert application details and our engineering team will respond with recommendations and pricing.