Custom Bolts & Screws
M3–M48 bolts and screws to ASTM, ISO and DIN, thread rolled after heat treat so grain flows with the thread.
Special bolts in alloy, stainless and titanium, thread rolled after heat treatment so the grain runs along the thread instead of being cut across it. Tensile testing per lot on request.
How we make it: Swiss CNC machining service →
3–5 weeks
100 pieces
ISO 9001:2015 · IATF 16949 · AS9100D
Technical Specifications
| Parameter | Value | Unit |
|---|---|---|
| Thread range | M3–M48 | metric |
| Thread tolerance | 6g / 6H | - |
| Property class | 8.8 / 10.9 / 12.9 | - |
| Length tolerance | ±0.2 | mm |
| Concentricity | 0.05 | mm TIR |
| Batch tensile test | On request | - |
Available Materials
- Alloy steel 4140 / 4340
- Stainless 304 / 316 / A2 / A4
- Stainless 17-4 PH
- Titanium 6Al-4V Grade 5
- Brass C360
- Aluminium 7075
Typical Applications
- Structural joints
- Engine and transmission fasteners
- Marine deck hardware
- Pressure vessel bolting
- High-vibration machinery
Surface Finishes
- Zinc plating
- Zinc-nickel plating
- Hot-dip galvanising
- Passivate
- Black oxide
- PTFE coating
- Anodise
Industries Served
- Aerospace
- Automotive & EV
- Energy & Oil & Gas
- Marine
- Rail
- Industrial Equipment
What drives the price of this part
Derived from the callouts on this page. Where a driver is not on the drawing, it is not on this list.
- Tolerance
- Thread tolerance at 6g / 6H is the tightest callout this family carries. Tightening a callout is a process decision, not a machining decision: below the standard ±0.005 mm the work moves to grinding or jig boring, and the price moves with it.
- Part size
- Thread range at M3–M48 metric decides which machine the part lands on and how many setups it needs. Size is the driver buyers most often leave out of a first enquiry, and it is the one that changes the quote fastest.
- Material
- The first material listed, Stainless Steel 17-4 PH (630), rates 4/10 on our machinability scale at 32 HRC (annealed) · 44 HRC (H900). On this shop's scale a harder alloy means slower passes and more tool changes, and that is cycle time the quote has to carry.
- Order size
- Minimum order is 100 pieces, where setup and tooling are amortised across the batch and per-part cost settles around cycle time and material. Below that quantity the same part costs more per piece, not less.
See how cycle time is calculated in the machining time calculator and what else moves a price in the cost driver reference.
How these parts are inspected
Matched to the callouts above and the instruments actually on the floor.
- Coordinate measuring machine (Zeiss CONTURA G2, two machines, GR&R 8.4% on the critical feature)
- Dimensional report against the drawing, with a 100% check on critical features rather than a sample
- Certificate of conformance and the mill certificate with every shipment
- Thread gauges over the full thread range on the drawing
- First article inspection to AS9102, because this family carries an aerospace or automotive certificate
The full equipment list, with counts, is on the capability page; the inspection sequence is on quality and inspection.
Questions buyers ask
- Rolled or cut threads?
- Rolled, unless the part is already hardened or has an interrupted thread. Rolling forms the grain along the thread root instead of cutting through it, which is typically 20–30% stronger in fatigue.
- Can you supply material certificates?
- Yes, EN 10204 3.1 for steel and stainless lots, with the heat number traced from the bar to the finished box. That is standard on anything going into a pressure or lifting application.
Related part families
Precision Washers & Spacers
Flat, conical and shim washers from 0.05 mm, stamped or fine-blanked with lapped flatness.
Studs & Threaded Rods
Continuous-thread and double-ended studs to B7, B16 and 316, with rolled threads and cut ends.
Custom Nuts
Hex, flange, nylon-insert and weld nuts to DIN/ISO/ASTM, M3–M48, with lot testing.