Hardened & Ground Machined Parts
Parts machined, heat treated and then ground or hard turned to hold the tolerance.
Parts that only get their final size after heat treatment, because hardening moves metal. The sequence is machine, harden, then grind or hard turn - never the other way round.
How we make it: Precision CNC machining service →
4–7 weeks
5 pieces
ISO 9001:2015
Technical Specifications
| Parameter | Value | Unit |
|---|---|---|
| Grinding tolerance | ±0.005 | mm |
| Hardness range | 45–62 | HRC |
| Surface roughness | Ra 0.4 | µm |
| Flatness (lapped) | 0.002 | mm |
| Distortion allowance | Left before grinding | note |
| Max size | 600 × 400 × 300 | mm |
Available Materials
Typical Applications
- Wear pads and guides
- Cam plates
- Tool components
- Locking plates
- Valve seats
Surface Finishes
- Ground
- Hard turned
- Lapped
- Nitrided
- Black oxide
Industries Served
- Industrial Equipment
- Tooling & Mould Making
- Energy & Oil & Gas
- Automotive & EV
- Rail
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
- Grinding tolerance at ±0.005 mm 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
- Max size at 600 × 400 × 300 mm 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.
- Surface finish
- Surface roughness at Ra 0.4 µm. Every step below the ordinary as-machined Ra 1.6 µm adds a finishing pass; a callout on a face nobody touches is the most common over-specification we quote.
- Material
- The first material listed, Bearing Steel 52100 (100Cr6), rates 4/10 on our machinability scale at 60–66 HRC hardened · 183–217 HB annealed. 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 5 pieces, so on a first order setup and programming are spread over very few parts and they are most of the price. Repeat orders at the same quantity are cheaper without anything on the drawing changing.
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
- Surface roughness tester (Mitutoyo) against the Ra callout
- Rockwell hardness tester on the part, not only against the mill certificate
The full equipment list, with counts, is on the capability page; the inspection sequence is on quality and inspection.
Questions buyers ask
- Why leave material on before hardening?
- Because normalising, quenching and tempering move the part by 0.1–0.3 mm, and scale forms on the surface. Grind that away and you have your dimension; machine to size first and it is scrap.
Related part families
EDM Cut Components
Wire and sinker EDM for hardened tool steel, sharp internal corners and features a cutter cannot reach.
CNC Machined Plates & Bases
Machined base plates and mounting plates, faced flat and drilled to a pattern.
Machine Tooling & Inserts
Form tools, bushings and production inserts, hardened and ground to hold size across a long run.