Custom Fasteners

When the Fastener Isn't in Any Catalogue

Most fasteners you can simply buy. The ones that stop a job are the ones you can't: a non-standard thread, a special head or drive, an unusual length, a shoulder or stepped bolt, an exotic material — or a fastener from old equipment that nobody sells anymore. Distributors quote huge minimums or simply say "non-stock".

EKINSUN makes exactly those. We manufacture custom and non-standard fasteners to your drawing, or reproduce them from a single worn sample, in low to medium volumes. No CAD file, no thousand-piece minimum, and a quote within 12 hours.

Send Us Whatever You Have

You don't need a spec sheet to start. Any one of these is enough:

Fasteners We Make

Popular: special fasteners · castle & slotted nuts · drilled-head & cross-drilled bolts (lock wire, split pin) · bearing lock & spindle nuts (KM/AN, DIN 981/1804) · tall & thin nuts (custom nut heights, reduced A/F) · large & heavy hex nuts (M30–M160, special/LH pitch) · machine keys (parallel/Woodruff/gib-head, oversized for worn keyways) · dowel pins · clevis pins · pivot pins · taper pins · lock pins with a retaining chain (linch, clevis and ring-head pins, Ø5–Ø40) · custom bolts · hex bolts · banjo & hollow bolts · large & oversize bolts · set screws & grub screws · thumb & knurled screws · custom & thick washers · shoulder bolts · partially threaded bolts (grip length to your stack) · titanium bolts · 316L stainless bolts · double-ended studs · threaded rods & studs · internally threaded rods (tapped both ends, any length) · ACME & trapezoidal lead screws · trapezoidal lead screws Ø4–Ø24 with nuts · coupling nuts · knurled & thumb nuts · weld bolts & weldable studs · custom eye bolts ·U-bolts · square head & coach bolts ·replacement bolts from sample · non-standard thread bolts · obsolete & discontinued fasteners · Whitworth & BSF bolts. Need something not listed? Send the sample or sketch and we'll quote it. · chipper knife bolts · fine-thread bushings · locking threaded bushings · screws with pre-applied threadlocker · indexing plungers

Not sure what the part is called? The fastener types chart lists every family with its DIN or ISO number, the size range a catalogue holds and the change that makes it a custom part.

Nuts by form: rivet nuts · self-clinching nuts · weld nuts · cage nuts · flange nuts · cap & dome nuts · wing nuts & wing screws · T-slot & square nuts · insert nuts for wood · threaded inserts for plastics · brass coupling nuts 8-32 to M30 · 304 stainless coupling nuts M2–M24, 10–100 mm.

Screws by head, drive and thread: socket head cap screws · machine screws · self-tapping & self-drilling screws · SEMS screws · captive panel screws · security screws · brass fasteners · plastic fasteners.

Washers, rings, pins and knobs: washer types · retaining rings & circlips · circlip groove sizes · spring pins & cotter pins · blind, solid & semi-tubular rivets · clamping knobs & levers.

Added 2026-09: thin washers and precision shims (0.05–1 mm), plastic and insulating washers, precision adjustment screws with fine and ultra-fine threads and the M3 × 0.25 adjustment screw made from a real RFQ.

Also added 2026-09: hanger bolts (wood-screw thread to metric machine thread, M4–M12, made to order) and fine thread and inch socket head cap screws (ISO 12474 and UNC / UNF, solid or hollow, made to order).

Also added 2026-09: the knurled thumb screw size chart (DIN 464, DIN 653 and GB/T 834 dimensions M2–M10, 304 against 316 stainless, made to order from 1 piece).

What We Do — and Don't

We are not a commodity hardware distributor, and saying so keeps our pricing and lead times focused where they help you:

We make this	We don't do this
Non-standard / special threads & heads	Standard M6 / M8 catalogue bolts
Replacement & obsolete fasteners from a sample	Bulk commodity hardware off the shelf
Exotic materials, custom lengths, low volumes	Mass-distribution stock items

If a standard part covers it, a distributor will be cheaper — and we'll tell you so. If it doesn't exist, that's exactly what we're for.

Where the Fastener Catalogue Stops

Standard sizes in standard classes are stocked everywhere and you should buy those — we say so in the quote. The rows below are the ones buyers send us, because that is where the stock list runs out. Each links to the page that carries the full dimensions.

What you need	In the catalogue?	What we machine
M6–M24 hex or socket head bolts in 8.8 or 10.9, standard lengths	Yes — stocked everywhere	Buy it from stock. On a standard bolt in a standard class no one-off can match that price, and we will say so. Grade chart →
A large nut in a pitch outside the DIN 934 fine series — M120×3, or a left-hand fine pitch	No — the series gives each size one or two fine pitches (M90×2 and M100×2 are stocked)	Single-pointed on the lathe to the pitch the rod already carries, nut and bolt as a pair if you need both. Fine pitch above M64 → · Large nut dimensions →
A194 2H properties on a metric thread — M30, M36, M30×1.5	No — the standards do not cross	A 2H-grade body carrying the metric thread your studs use. Heavy hex nuts →
The old DIN across-flats — 17 mm on M10, 19 on M12, 22 on M14	Rare, and vanishing	Head milled to the DIN width on a bolt of the same class and thread. Wrench size chart →
An M12 nut 14 mm tall, buried in a 14 mm counterbore	No — the standards jump 10.8 → 18.0 mm	Turned to the height you state, full-strength material, one piece up. Tall & thin nuts →
A drilled head above M16, for lock wire	No	Turned from bar to your length, holes through two or three corners. Drilled head bolts →
CEI/BSC, small BA, odd tpi counts	Rare to none — old stock only, if ever	Machined from your sample, no drawing needed. Obsolete fasteners →
U-bolt inside widths between the pipe series — 50, 62, 70 mm	The catalogue jumps straight past them	Bent and threaded to your exact inside width. U-bolts →

How We Hold the Critical Features

Feature	How we hold it
Thread	Gauged to the matched standard (metric / UNC / UNF / BSW / BA) or reproduced exactly from the sample
Head & drive	Hex, socket, slotted, Torx, custom — to original form
Diameters & shoulders	Turned tight, typically ±0.02–0.05 mm on fitting features
Material & finish	Verified material; black oxide, zinc, passivation or anodising as needed

No Drawing? We Reverse Engineer It

Most fastener jobs arrive as a single old part. We measure it, rebuild the drawing for free, confirm with you, then machine. See how we reverse engineer parts and make parts from a sample.

Materials

What to Send Us

• The sample fastener (even stripped/sheared), or photos with one known dimension
• Thread size or pitch if you know it — or let us gauge it
• What it fastens and the material/finish you need (or the application, and we'll advise)
• Quantity — a few spares or a production run
• Delivery country (we ship worldwide)

Custom, Special, Bespoke — the Same Fastener by Three Names

US buyers say custom fasteners, UK and Irish engineers write bespoke fasteners, and older drawings just say special. Whatever the word on your enquiry, it means the same thing here: a bolt, stud, nut or pin made to order to your print or sample rather than pulled from a catalogue — in imperial and Whitworth threads as readily as metric.

For Distributors: Neutral Packaging, Your Part Number, Delivery to Your Customer

Industrial distributors order from us what their catalogue does not stock: an odd size, a run of 50,000 screw-and-washer sets with a pre-applied threadlocker, a part the maker no longer supplies. The order ships in plain packaging without the EKINSUN name, each bag labelled with the distributor’s part number and quantity, to the distributor or straight to the end customer’s goods-in. From 1 piece; the more pieces, the lower the unit price; quote in 12 hours. The set a European distributor asked for is on screws with pre-applied threadlocker.

Camber bolts and toe adjust cam bolts — eccentric bolt, two cam plates and nut, in class 12.9, by OEM number or from the old kit — are on camber bolt kits.

Frequently Asked Questions