5-Axis CNC & Horological Architecture
The Custom Rolex Day-Date 36 Natural Ferrite Stone Dial 18K Yellow Gold Deep Crystal Optics Reference 18238 is a 5-axis Swiss CNC commission machined in 18K Yellow Gold Au750 (36.0 mm x 12.0 mm) weighing 141.8g on our Mettler-Toledo analytical balance, driven by Rolex Manufacture Cal. 3155 regulated to +0.4 s/d, 296 deg at 28,800 vph with a 72-hour power reserve beneath a double anti-reflective sapphire crystal.
| 01 / CNC Blueprint Entity & Reference | Rolex — Oyster Perpetual Day-Date 36 | Ref. 18238 | SKU: AT-AU750-18238-W180 |
|---|---|
| 02 / 5-Axis CNC Metallurgy & Gold Purity | 18K Yellow Gold Au750 — Au750 — 75.0% Pure 18K Gold Bullion (XRF Verified) • Hallmarked Solid Precious Metal |
| 03 / Analytical Bench Weight (1:1 Reference Mass) | 141.8g — 1:1 Authentic Reference Mass Verified on Mettler-Toledo Analytical Scale |
| 04 / Custom Bezel, Gem-Setting & Case Geometry | Signature Rolex Fluted 18K Yellow Gold Bezel with Anti-Reflective Scratch-Resistant Sapphire Crystal • 141.8g 18K Yellow Gold • 36.0 mm x 12.0 mm |
| 05 / Regulated Super Clone Movement Calibre | Rolex Manufacture Cal. 3155 — Swiss Super Clone Mechanical Calibre Regulated to +0.4 s/d, 296 deg |
| 06 / Barrel Power Reserve & Balance Frequency | 72-Hour Power Reserve • 28,800 vph (4 Hz) Free-Sprung Balance Wheel |
| 07 / Optical Sapphire Crystal (Double AR) & Sealing | Scratch-Resistant Sapphire Crystal with Double Anti-Reflective Coating • 100m / 330 ft - Twinlock Screw-Down |
| 08 / Bespoke Dial & Integrated Bracelet Spec | 36.0 mm x 12.0 mm • Metallic Natural Ferrite Stone Dial with Solid 18K Gold Applied Hour Markers & Hands • Integrated 18K Yellow Gold Solid Link Bracelet & Deployant Clasp with Deep Laser Hallmarks |
Engineered inside our Geneva 5-axis CNC Rolex custom atelier, the Custom Rolex Day-Date 36 Natural Ferrite Stone Dial 18K Yellow Gold Deep Crystal Optics Reference 18238 is machined from solid 18K Yellow Gold Au750 billets to micron-level tolerances (36.0 mm x 12.0 mm). Every bevel, lug chamfer, and Metallic Natural Ferrite Stone Dial with Solid 18K Gold Applied Hour Markers & Hands is hand-finished on our watchmaker bench, yielding a certified reference weight of 141.8g verified under our Fischer XRF and Mettler-Toledo QC protocol.
What Are the Horological & Metallurgical Benchmarks of Rolex Day-Date President Ref. 18238?
The Rolex Day-Date President Reference 18238 is a precision-engineered luxury timepiece crafted in 18K Yellow Gold Au750 (36.0 mm x 12.0 mm) with Metallic Natural Ferrite Stone Dial with Solid 18K Gold Applied Hour Markers & Hands, Signature Rolex Fluted 18K Yellow Gold Bezel with Anti-Reflective Scratch-Resistant Sapphire Crystal, and a verified Mettler-Toledo mass of 141.8g, because the Rolex Manufacture Cal. 3155 movement is regulated across six positions to chronometric tolerances with a 72-hour power reserve.
5 Core CNC & Chronometric Specifications:
- Blueprint Reference: Custom Rolex Day-Date 36 Natural Ferrite Stone Dial 18K Yellow Gold Deep Crystal Optics — Official Ref. 18238 (SKU: AT-AU750-18238-W180).
- 5-Axis CNC Metallurgy: 18K Yellow Gold Au750 case (36.0 mm x 12.0 mm) and Signature Rolex Fluted 18K Yellow Gold Bezel with Anti-Reflective Scratch-Resistant Sapphire Crystal with hand-polished chamfers.
- Verified Bench Mass: 141.8g confirmed on a Mettler-Toledo analytical gram scale prior to dispatch.
- Super Clone Calibre: Rolex Manufacture Cal. 3155 operating at 28,800 vph (4 Hz) with 72-hour power reserve and +0.4 s/d, 296 deg accuracy.
- Sapphire Optics & Sizing: Double anti-reflective sapphire crystal, 100m / 330 ft - Twinlock Screw-Down sealing, and 19 wrist sizing options (14.0–22.0 cm).
Within the Rolex Day-Date President horological sub-silo, collectors also compare the Rolex Day-Date 36 Gibeon Meteorite Dial 18K Everose Gold Ref. 118135 (118.9g) and the Rolex Day-Date 40 18K White Gold Geneva Atelier Spec Ref. 228239 (210.9g).
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- Metallurgical & 4K QC Verification: Fischer XRF Au750 Protocol • 3-Year Mechanical Warranty • Insured Armored Delivery
How is the 18K Yellow Gold case of this Rolex 18238 machined?
Our Geneva CNC specialists mill the monobloc middle case, bezel, and bracelet geometry on 5-axis Swiss machining centers in 18K Yellow Gold Au750 to achieve the authentic 141.8g reference mass.
Can the bracelet or strap be pre-sized to my exact wrist circumference?
Yes. Choose from 19 precision wrist circumference options (14.0 cm to 22.0 cm, or full unsized factory length). All removed solid links are sealed inside your presentation box.
How is the Rolex Manufacture Cal. 3155 tested on the atelier workbench?
We record a personalized 4K bench video showing the Rolex Manufacture Cal. 3155 (28,800 vph, 72-hour reserve) running at +0.4 s/d, 296 deg on our Witschi Chronoscope alongside Fischer XRF and Mettler-Toledo gram scale verification.
What dial and bezel specifications distinguish Rolex Day-Date President Ref. 18238?
Reference 18238 combines Metallic Natural Ferrite Stone Dial with Solid 18K Gold Applied Hour Markers & Hands and Signature Rolex Fluted 18K Yellow Gold Bezel with Anti-Reflective Scratch-Resistant Sapphire Crystal within a 36.0 mm x 12.0 mm 18K Yellow Gold Au750 case weighing 141.8g, verified via Fischer XRF spectroscopy and powered by Rolex Manufacture Cal. 3155.
Custom Rolex Day-Date 36 Natural Ferrite Stone Dial 18K Yellow Gold Deep Crystal Optics Ref. 18238
5-Axis Swiss CNC 18K Yellow Gold Au750 • 141.8g Verified Mass • Regulated Rolex Manufacture Cal. 3155