When the Adapter You Need Doesn't Exist
Catalogues cover the common adapters. The one you actually need is often the one no one stocks: an odd thread combination, a metric-to-imperial conversion, a fitting for a discontinued sensor or pump, or a connector that has to seal between two parts that were never meant to join. You already know what you need — you just can't buy it.
EKINSUN machines those. We make custom adapters and fittings to your spec, or copied from a sample, in the thread, size and material you need — single pieces through small production. No CAD file, no catalogue limits, and a quote within 12 hours.
Send Us Whatever You Have
You don't need a drawing — just enough for us to nail the two ends and the seal:
A sample
The old adapter or both parts it must join — we measure the threads & bore.
The two threads
Tell us each side (e.g. 1/4" NPT to M12×1.5) and we make the link.
A photo
Clear photos with one known dimension or a caliper in shot.
A sketch
A rough drawing with the sizes and angle you need.
A broken fitting
Cracked or stripped is fine — we recover the geometry.
Adapters & Fittings We Make
Thread Adapters & Conversions
Application Fittings
Special
Popular: custom thread adapters (BSP/NPT/metric) · custom metric thread adapters (mixed-pitch, double-male) · BSP to NPT adapters · hydraulic adapters (JIC/ORFS/SAE) · precision machined fittings · flange adapters · motor adapter rings & plates (mount a new motor to an old pump/gearbox) · stainless steel connectors. By application: plumbing adapters · sensor adapters · pressure gauge thread adapters (M20×1.5/M14×1.5 ↔ G/ZG/NPT) · tri-clamp adapters (sanitary ferrule ↔ thread/barb/flange) · hose barb adapters (metric threads, odd hose IDs) · cable gland & conduit adapters (industrial connectors ↔ protective conduit, short body, non-standard pitches like M15×1) · automotive fuel-line adapters · motorcycle adapters. By form: male-to-male (double-male) · female-to-male & hex reducing bushings · female-to-female (reducing coupler, M6–M64) · hex thread adapters (hex nipples & bushings, SW 10–95) · metric to imperial (UNC/UNF/BSP/NPT). Guides: connect two different threads · connect different thread pitches (coarse vs fine) · thread adapter types (male-female, double-male, female-female). By size: M30 to M24 (incl. mixed-pitch M30×3.5→M24×2) · M24 to M20 · M20 to M16 · M16 to M12 · M12 to M10 · the full metric size table · large threads M33–M52 (coarse & fine pitch) · large metric to NPT M50–M100 (cable-gland ↔ conduit conversions to 4" NPT) · 13/16-28 UN to M20×1.5 (IP67 connector ↔ cable-gland threads, 304 stainless). Need a combination not listed? Tell us the two ends and we'll quote the adapter that joins them.
Where Our Adapters & Fittings Are Used
One custom fitting, many systems. We machine thread adapters and fittings for engineers and procurement across six application areas — any thread (BSP, NPT, metric, UNF, JIC), any material, from a single piece to bulk:
Whatever the Equipment — Where the Catalogue Stops and We Start
An adapter is never bought for its own sake. It sits between a machine and a hose, a sensor and a block, a tank and a line — and it is the equipment that decides whether the part you need exists. The same rule holds on every machine we've quoted for: if both ends are common standards, a catalogue has it; the moment one end belongs to your specific equipment, nobody lists it.
| The equipment it sits on | What the catalogue covers | Where we take over |
|---|---|---|
| Hydraulic machinery — excavators, presses, farm equipment | Standard JIC/ORFS/BSPP pairs, stocked | The odd port on an obsolete machine, the pair no one stocks, the custom hydraulic adapter between two brands' couplings |
| Boilers, water heaters, heat exchangers | Dielectric unions and nipples in standard sizes | The odd boiler tapping on a discontinued model, transition pieces between metric and imperial systems |
| Engines & vehicles — sensors, fuel lines, turbos | Common AN/NPT conversions | Sensor adapters for a port the sensor maker never anticipated, fuel-line conversions for engine swaps |
| Packaging & process lines | Tri-clamp and standard sanitary sizes | Tri-clamp to thread conversions in the size your line actually has, format-change parts |
| Instruments & gauges | Common gauge threads | Gauge adapters where the instrument is European and the port is American — or the reverse |
| Machines whose maker is gone | Nothing — the thread may not even be identifiable | We identify the thread from the part or ten pitches of it, then machine the mate. How we identify an unknown thread |
If you can't name the thread, that's normal — and it's our job, not yours. Send the part, or both parts it must connect, or photos with a rule in shot. Naming the standard is the first thing we do with every enquiry — and whether you'd have one made as an adapter, an adaptor (the UK and Australian spelling), a bush or a nipple, it's the same machined part to us.
Get the Threads & Seal Right
An adapter only works if both ends fit and it doesn't leak. We focus the precision there — see the custom sealed metal parts we machine and a 316 stainless sealed pair we made, contact proven before dispatch:
| Feature | How we hold it |
|---|---|
| Threads (both ends) | Gauged to BSP / NPT / metric / UNF / JIC / ORFS / SAE, or reproduced from the sample |
| Sealing faces & tapers | Machined to the matched seal type (taper, cone, O-ring boss, flat) |
| Bore & flow | Sized so the adapter doesn't choke the line |
| Material & pressure | Brass, 316 stainless or steel chosen for the fluid, pressure and environment |
Technical Capabilities at a Glance
For engineers and procurement scoping a custom adapter or precision machined fitting — the standards, materials and tolerances we machine to:
| Thread Standards & Types | Machinable Materials | Precision & Custom Capability |
|---|---|---|
| NPT / NPTF (tapered pipe) Metric M (ISO coarse & fine) BSPP / BSPT (G & R) UNF / UNC (unified) JIC / ORFS / SAE JIS standard threads |
Stainless: 304, 316, 316L Brass / copper: C36000 & alloys Aluminium: 6061-T6, 7075 Titanium alloys Plastics: PEEK, PTFE, POM |
Tolerances down to ±0.005 mm (±0.0002") Surface finish Ra 0.8 to Ra 0.4 Thread fit classes 2A/2B, 3A/3B Volume: low-volume / small batch, 1 to 10,000+ pcs |
Build Your Adapter Spec — Instant RFQ
Configure a non-standard adapter against our CNC capabilities below. It generates clean RFQ text you can copy, or send straight to our engineers — no account, no CAD file.
Custom Thread Adapter Spec Configurator
Define both interfaces, material and batch size. We reply with lead time and pricing within 12 hours.
Custom adapter configuration…
No Drawing? We Reverse Engineer It
Send the parts or sizes
The old fitting, both mating parts, or the two thread specs to connect.
We measure & draw it
Threads, seals and bore captured; we rebuild the CAD for free. How it works →
Confirm, then machine
You approve the drawing, then we turn and inspect it. Copy from a sample →
Materials
Brass
The default for fuel, air, water and general fluid fittings — easy to seal, corrosion-resistant.
Ask about brass →Steel & aluminium
Carbon/alloy steel for high-pressure hydraulics; aluminium where weight matters.
4140 →Plastic Adapters — When Metal Is the Wrong Answer
Roughly a fifth of the adapters we quote end up in plastic, and usually for a reason the catalogue can't serve: the chemistry, not the pressure, is the constraint. A machined plastic adapter is turned from solid engineering polymer — not injection-moulded, so there is no tooling and no minimum, same as our metal work.
| Material | Pick it when | Watch out for |
|---|---|---|
| POM (acetal) | The default machined-plastic fitting — dimensionally stable, near-zero moisture uptake, food-contact grades available | Not for strong acids or prolonged hot water above ~80 °C |
| PTFE | Aggressive chemicals where nothing else survives; naturally low-friction seal faces | Soft — threads deform under high torque, so keep pressures modest |
| PP / PVDF | Chemical transfer lines; PVDF where temperature and purity both matter | PP is the budget pick but weakest mechanically |
| PEEK | High temperature plus chemistry plus load — the last resort that always works | Costs more per kilo than titanium; specify it only when the case demands it |
| PA (nylon) | Tough, cheap, fine for air and neutral fluids | Absorbs moisture and grows — avoid where a sealing dimension must hold in a wet line |
Plastic also solves two problems metal can't: galvanic isolation (a plastic transition between dissimilar metals stops the corrosion a brass one would feed) and weight on moving assemblies. If you're unsure which side of the metal/plastic line your part falls on, say what flows through it and we'll pick — that decision is included in the quote, not billed as engineering.
One Piece or a Thousand — Both Are Normal Orders
Adapters are the most quantity-diverse thing we make: the same week brings a single M35 gland reducer for one cabinet and a repeat batch of sensor bushings for a production line. Machining from bar serves both ends because there is no tooling to amortise — one piece has no surcharge to justify, and repeat batches run from the same proven program with price breaks quoted upfront. The second piece always costs a fraction of the first, because setup is paid once; how the price moves with quantity sets out the whole curve, including the honest point where a dedicated fittings line beats us.
What to Send Us
- The sample adapter, or both parts it must connect — or photos with one known dimension
- The thread on each end if you know it (e.g. 1/2" BSPP to 3/8" NPT)
- Fluid/medium, pressure and environment (so we pick the right material and seal)
- Quantity — one to prove the fit, or a batch
- Delivery country (we ship worldwide)
No CAD, no problem. Rebuilding the drawing is our job — free, confirmed with you before anything is cut. See how to order with no CAD file.
A note on branded parts. We make a compatible fitting to the original's form, fit and function from what you supply. We don't sell branded original products or imply affiliation with the original manufacturer.
Frequently Asked Questions
Yes — the main reason customers come to us. If the thread combination, size or material isn't a stock item, we machine it to your spec. Give us the two threads to connect (or a sample of each side) and we make the adapter that joins them.
Yes — conversion adapters between BSP (BSPP/BSPT), NPT/NPTF, metric, UNF/UNJF, JIC, ORFS and SAE, male or female, straight, elbow or tee, in your size and material.
Yes. Send the part — even worn or broken — and we measure the threads, bore, sealing faces and form, rebuild the drawing for free, confirm it, then machine. No drawing or part number needed.
Thread adapters, fuel, sensor, pipe and hydraulic adapters, air fittings, hose connectors, reducers, custom fittings and special connector components — straight, elbow, tee or cross, male or female.
Brass for general fluid and pneumatic use, 316 stainless for corrosion and marine, carbon/alloy steel for high pressure, and aluminium where weight matters — chosen for pressure, fluid and environment.
Low. Single pieces and prototypes as well as small to medium runs. Tell us how many you need and we quote accordingly.
We make a compatible fitting to the original's form, fit and function from the sample, drawing or photos you supply. We don't sell branded originals or imply affiliation with the original manufacturer.
Yes — machined from solid POM, PTFE, PP, PVDF, PEEK or nylon, not injection-moulded, so there is no tooling and no minimum, exactly as with our metal fittings. Plastic is usually the right call when chemistry is the constraint, when you need galvanic isolation between dissimilar metals, or when weight matters. Tell us what flows through the part and we pick the grade as part of the quote.
That is the normal case, not the exception. An adapter's geometry is set by the equipment it sits on, which is exactly why catalogues stop where your machine begins. Send the part, or both parts it must connect, or photos with a rule in shot — identifying the thread and the seal is the first thing we do, on any equipment: hydraulic machinery, boilers, engines, packaging lines, instruments, or a machine whose maker no longer exists.
Right here — this is exactly what EKINSUN does. We are a custom manufacturer: send a drawing, a sketch, the sample, or just the two parts that must connect, and we machine the adapter to order — metal or plastic, one piece or a batch, shipped worldwide with a quote in 12 hours. And if what you need turns out to be a standard catalogue item, we say so instead of quoting it.
Machining companies that work from bar stock rather than from moulds — EKINSUN is one. What matters when you pick such a factory: they should cut and gauge each thread to its own standard, charge no tooling cost, accept one piece as a normal order, and be willing to identify the thread for you when you can't name it. A supplier who insists on a finished CAD file before quoting is answering a different question from the one you're asking.
Get an Adapter Quoted
Sample or the two threads — that's all we need. Engineers reply in 12h.
// Qty & price
1 pc
Sample price
Confirm fit before a run
10–50
Unit price drops
Setup cost shared
100+
Best price
All tiers quoted upfront
- →No distributor — you pay the maker directly
- →CAD saved after first order — reorder anytime at lower unit price
EXPLORE
- → Custom Thread Adapters
- → Custom Metric Thread Adapters
- → BSP to NPT Adapters
- → Hydraulic Adapters (JIC/ORFS)
- → Precision Machined Fittings
- → Plumbing Thread Adapters
- → Sensor Thread Adapters
- → Pressure Gauge Thread Adapters
- → Tri-Clamp Adapters
- → Hose Barb Adapters
- → Automotive Fuel-Line Adapters
- → Custom Fasteners
- → Custom Metal Parts
- → Replacement Parts
- → Parts From a Sample
- → Reverse Engineering
- → All Custom Parts