Custom Screws — Made to Your Drawing

What this part is and where it is used

Custom screws are headed fasteners with an external thread that engages a tapped hole, a threaded insert or a nut. They are machined to your drawing, so the head, thread, length and material come from the print rather than a stock table. In any assembly, screws and fasteners carry clamping, retention and adjustment loads across instruments, enclosures and machines.

Buyers specify custom screws when no catalog size fits: an uncommon thread, a special drive recess, a non-standard length, or an alloy such as 316L or titanium. They show up in electronics hardware, medical devices and small mechanisms where a stock screw is too long, too short or the wrong material. Nuts and bolts and screws are often ordered together, but we also run screws on their own when the mating threads already exist in your parts.

Head types and drive styles

We cut the head and drive recess on our own floor together with the thread, not by modifying stock screws. Common heads we machine:

• Pan head — general-purpose, with a flat bearing underside.
• Flat (countersunk) head — sits flush in a countersunk seat.
• Button head — a low rounded profile with a socket drive, for limited head height.
• Socket head cap — an internal hex drive with a compact, high-torque head.
• Hex head — external wrench drive for machine and structural work.
• Truss head — a wide, low dome that spreads load over thin sheet.
• Set screw (grub screw) — headless, for locking shafts, collars and adjusting positions.
• Shoulder screw — a precision unthreaded shoulder for pivots and guides.

Drive styles are an external hex wrench or an internal hex socket, chosen from your drawing. A specialty screw with a custom drive recess or undercut is one drawing away — see our custom bolts for the headed counterpart.

Thread forms and standards

Threads are cut on our own floor to the form on your print. Metric screws use M-series threads and inch screws use UNC/UNF coarse or fine series, with BSP and NPT where a sealing thread is specified. We work to DIN, ISO and ANSI/ASTM geometry references, and the drawing always wins — the full list is on our thread standards page.

The tolerance class comes from the print: commonly 6g for external threads and 6H for the mating internal thread. Pitch in millimeters or threads per inch is confirmed per drawing, and left-hand, fine-pitch and partially threaded screws are cut from the same setup.

Dimensions we work to

Diameter, thread length, overall length, head diameter and drive recess all follow your drawing rather than a stock table. General dimensions are held to ISO 2768-m unless your print states otherwise, and precision features — a shoulder, a bearing diameter or a thread run-out — are held to ±0.01 mm. See our tolerances page.

A 50-piece first run proves the geometry and finish; production repeats it in 25–35 days after approval. Send a STEP, DWG or PDF and we check the dimensions against our drawing requirements before quoting.

Materials, threads and finishes

Common materials are aluminium 2024, 5052, 6061 and 7075; stainless steel 303, 304, 316, 316L and 17-4PH; carbon and alloy steel 1045, 1215, 4140, D2 and O1; brass, copper and bronze; and titanium. Stainless screws suit corrosion-facing hardware — 303 for volume, 304 for general service, 316L for chlorides and 17-4PH where the screw also carries load; grade detail sits on our materials index, then the stainless steel parts, aluminium parts, steel parts, brass and copper parts and titanium parts pages.

Threads are cut to metric or inch references, or to DIN and ANSI/ASTM standards — our thread standards page lists the options. We cut coarse and fine pitches, left-hand threads and partial threads, so a screw stops exactly where your print says. Finishing runs through our vetted partner network under one quality process: zinc plating, black oxide, passivation and anodizing for aluminium.

Industries and applications

Custom screws and bolts turn up in automotive, aerospace, medical, hydraulic and pneumatic and marine assemblies. Tight-clearance instrument work and stainless fasteners are the requests we see most often.

Why order this part from our factory

We machine custom screws in our own factory in Qidong City, Jiangsu Province — the head, thread and body are all cut on our floor. General work is held to ISO 2768-m unless stated on the drawing, with precision features to ±0.01 mm. Orders start from 50 pieces; samples take 5–10 days and production 25–35 days. Monthly capacity runs over 100,000 parts, scheduled flexibly per order. Send a drawing and we return DFM feedback with a quote within 24 hours, then ship with a material certificate (MTR) and pre-shipment photos. Buyers who have searched screw manufacturers in usa for a drawing-based part often route it here for the same reason. WhatsApp us or use the quote form.

What set screws are and where they are used

A set screw holds one part in position against another. It is fully threaded and normally headless, so it can sit flush or below the surface of the outer part, and its point presses on a shaft, a collar or a bore — the joint is held by friction, or by the point biting into the mating surface. That is the whole purpose: it resists rotation or movement of one part relative to another, rather than clamping two parts under load. We manufacture set screws to your drawing in our own factory in Qidong City, Jiangsu Province, China, and they ship with a material certificate (MTR) and pre-shipment photos. Typical use is fixing a collar, pulley or gear on a shaft, holding a knob or handle on a spindle, setting an adjustment stop, and locking a threaded insert or a bushing in place.

Point types and drives we manufacture

The point is the function of the part, so it is the first decision on the drawing:

• Cup point set screws — a concave point that bites into the shaft, giving the strongest resistance to loosening. The usual default for a collar or a knob on a plain shaft.
• Cone point — locates in a drilled dimple, so the position is positive rather than friction-dependent.
• Flat point — presses without marking the shaft; used where the mating surface must not be damaged.
• Dog point and half-dog — a short pilot enters a drilled hole for a positive location and more drive torque.
• Oval point — a rounded point that seats in a dimple without cutting.

Drives come from the drawing as well. A hex socket drive — an allen set screw — is the common choice, with slotted, Torx and square on the same route; where the joint needs a head, hex head set screws and button head set screws are produced to the same standard. These parts run alongside our custom screws, custom bolts and threaded inserts programmes.

Dimensions and point geometry

Thread size, length, drive size and point geometry all come from your drawing, so there is no catalogue ceiling on the size we will quote. General dimensions are held to ISO 2768-m unless the print states otherwise, and precision features — the point angle, the cup depth, the pilot diameter on a dog point — are held to ±0.01 mm. Where a hardness specification is called out, confirm it with us in DFM: the point has to survive being driven into the mating surface, so the material and heat treatment route is chosen against that requirement rather than assumed. A 50-piece first batch validates the thread fit and the point, then production repeats it in 25–35 days after approval. Send a STEP, DWG or PDF and we confirm the dimensions against our drawing requirements before quoting.

Why order set screws from our factory

We machine set screws in our own factory in Qidong City, Jiangsu Province, China — thread, drive and point are produced under one route. General work is held to ISO 2768-m unless stated on the drawing, with precision features to ±0.01 mm. Orders start from 50 pieces; samples take 5–10 days and production 25–35 days. Monthly capacity runs over 100,000 parts, scheduled flexibly per order. Send a drawing and we return DFM feedback with a quote within 24 hours, then ship with a material certificate (MTR) and pre-shipment photos. WhatsApp us or use the quote form.

What a socket head cap screw is used for

A socket head cap screw drives from the inside of a cylindrical head with a hex key. That recessed drive is why it is chosen where there is no room to swing a wrench, where the head must sit flush and compact against a machined face, or where the fastener has to be tightened from directly above in a confined pocket. Machine tools, fixtures, dies, pumps, robotics and enclosure assemblies are the usual homes for them.

We supply socket head cap screws by whichever route the order calls for. Standard sizes in volume run on cold heading equipment, where the socket is formed in the head and the thread rolled; non-standard head diameters, special shank lengths, unusual materials and small to mid-size runs are machined from bar stock to your drawing. Either way the head diameter, socket depth, shoulder length and thread relate to each other on the same drawing, rather than being assembled from a catalogue of separate parts.

Head, drive and shank options

• Cylindrical socket head (SHCS) — the standard profile: a compact head with a hex socket, used for high clamping force in tight envelopes.
• Button head — a low, domed head for visible applications where a softer profile is preferred.
• Flat / countersunk head — sits flush in a countersunk hole, common on moving parts and covers.
• Low head — reduced head height where clearance above the part is limited.
• Hex socket drive — the default; Torx and pin-in-hex are reviewed against your drawing where tamper resistance or higher torque transfer matters.
• Shank variations — full thread, part thread with a plain shoulder, reduced shank, or a longer shoulder used as a locating pin.

Tell us the application and we will confirm the head, drive and shank combination in the DFM response that comes with your quote.

Threads, sizes and standards

Threads are machined to the standard on your drawing: metric (M), inch UNC and UNF, or a sealing thread such as BSP or NPT where the part has to seal as well as fasten. Standards like DIN 912, ISO 4762 and ANSI B18.3 are used as references for head geometry, not as a fixed product list — the drawing always wins.

Thread pitch, class and fit are confirmed before production, and the thread standards page explains how we handle pitch, class and gauging in plain terms.

Hole and hex socket geometry

The socket is what makes or breaks this fastener. It has to accept the key cleanly, take torque without rounding, and hold its depth so the key does not bottom out early. Because the socket is machined and finished in the same route as the head, we can control wall thickness around the recess and keep it even — which is the part that matters when a customer strips a screw on the assembly line.

Where the screw is used at high torque or repeatedly assembled, tell us and we will confirm the drive size and socket depth against the duty in the DFM review rather than leaving it to the drawing alone.

Materials and finishes

We machine socket head cap screws in stainless steel 303, 304, 316, 316L and 17-4PH, carbon steel 1045 and free-cutting 1215, alloy steel 4140, brass and titanium. Stainless is the usual choice for corrosive or outdoor service; 4140 is chosen where strength matters more than corrosion resistance, and 17-4PH covers the joint that needs both. The full grade list is on the materials page.

Finishes include black oxide, zinc plating, nickel plating and passivation for stainless, all applied through our vetted partner network under one quality process. Finish choice is confirmed with the drawing, because plating thickness changes the thread fit on small sizes.

Why order socket head cap screws from our factory

• Machined to your drawing, not picked from a catalogue — head, socket, shank and thread all follow your file.
• Precision where it counts — shank and bore features held to ±0.01 mm, ISO 2768-m elsewhere, with tight features priced separately.
• Low entry quantity — from 50 pieces, so a first run or a service batch does not mean a container.
• Documents with the order — material certificate (MTR) and pre-shipment photos, see what ships with your order.
• Matching hardware — nuts, washers and spacers to the same drawing set, from the same machining floor.

Send the drawing and quantity for DFM feedback and a price within 24 hours.