{"id":2155,"date":"2026-05-12T12:45:02","date_gmt":"2026-05-12T04:45:02","guid":{"rendered":"https:\/\/tigweldingaluminum.com\/?post_type=cxb_products&p=2155"},"modified":"2026-05-15T09:56:45","modified_gmt":"2026-05-15T01:56:45","slug":"cnc-machining","status":"publish","type":"cxb_products","link":"https:\/\/tigweldingaluminum.com\/fr\/products\/cnc-machining\/","title":{"rendered":"17-4 PH Stainless Steel Medical CNC Machining | Reliable 5-Axis Spinal Surgical Instrument Parts"},"content":{"rendered":"

5Axis CNC Machining 17-4 PH Stainless Steel Surgical Instrument:<\/h2>\n\n\n\n

At Flow Wing Metal, we specialize in CNC machining for high-precision medical devices, aerospace components, and industrial parts. Our expertise in 5-axis CNC machining allows us to produce complex, monolithic parts with tight tolerances, minimizing assembly and improving reliability.<\/p>\n\n\n\n

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CNC Equipment at Flow Wing Metal:<\/h2>\n\n\n\n

Our machine shop is equipped with a range of CNC machining to address diverse part geometries, volumes, and tolerances.<\/p>\n\n\n\n

Client: <\/strong>OS Medical (ISO 13485 certified, Germany)<\/p>\n\n\n\n

Industry: <\/strong>Medical Device (Spinal Surgery)<\/p>\n\n\n\n

Challenge: <\/strong>OS Medical required a spinal pedicle screwrod reduction instrument used in minimally invasive spine surgery. The part (150mm total length, 12mm maximum diameter)<\/p>\n\n\n\n

featured:<\/strong><\/p>\n\n\n\n

A complex, ergonomic handle with undercut finger grooves.<\/p>\n\n\n\n

A distal “reduction tab” with a precise 2.5mm \u00d7 3mm rectangular slot (tolerance \u00b10.01mm).<\/p>\n\n\n\n

A cannulated (hollow) shaft with a 2.0mm internal throughhole.<\/p>\n\n\n\n

A ratcheting engagement interface requiring a 0.15mm radius root (sharp internal corner impossible with standard ball end mills).<\/p>\n\n\n\n

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Original challenge:<\/h2>\n\n\n\n

The instrument was previously manufactured as a 3component assembly (handle machined separately, shaft with broached slot, ratchet insert welded in place). <\/p>\n\n\n\n

This resulted in:<\/strong><\/p>\n\n\n\n

High assembly labor cost.<\/p>\n\n\n\n

Weldment weak points (potential for crevice corrosion after sterilization).<\/p>\n\n\n\n

Inconsistent slot positioning (\u00b10.08mm across batches) leading to poor instrument fit intraoperatively.<\/p>\n\n\n\n

8 weeks lead time.<\/p>\n\n\n\n

OS’s request:<\/strong> <\/p>\n\n\n\n

A single piece, weld-free, monolithic instrument machined from 174 PH stainless steel (precipitation hardened, high strength, corrosion resistant), with:<\/p>\n\n\n\n

No assembly required.<\/p>\n\n\n\n

Slot tolerance \u00b10.01mm (half of previous tolerance).<\/p>\n\n\n\n

Internal ratchet feature with 0.15mm root radii (EDM or 5axis machining).<\/p>\n\n\n\n

Lead time \u2264 4 weeks for 200 units.<\/p>\n\n\n\n

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The Flow Wing Metal Execution:<\/h2>\n\n\n\n

Step 1: Material Selection & Preparation of CNC Machining<\/h3>\n\n\n\n

Material:<\/strong> 174 PH stainless steel bar, Condition A (solution annealed \u2013 softer for machining), then agehardened to H900 condition postmachining (yield strength \u2265 1,170 MPa \/ 170 ksi).<\/p>\n\n\n\n

Bar size:<\/strong> 16mm diameter \u00d7 250mm length blanks.<\/p>\n\n\n\n

Certification: <\/strong>Material traceable per ASTM A564 with mill test reports (MTRs) and biocompatibility verification (ISO 109935 noncytotoxicity).<\/p>\n\n\n\n

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Step 2: CNC Programming & Simulation<\/h3>\n\n\n\n

CAM Software: <\/strong>Mastercam 2024 with 5axis simultaneous module.<\/p>\n\n\n\n

Machine: <\/strong>DMG MORI DMU 65 (5axis machining center with 20,000 RPM spindle, HSK63 tool holder, throughspindle coolant at 70 bar\/1,000 PSI).<\/p>\n\n\n\n

Workholding:<\/strong> Custom soft jaws with a dovetail fixture providing 5sided access.<\/p>\n\n\n\n

Toolpaths:<\/strong><\/p>\n\n\n\n

Roughing: <\/strong>High efficiency dynamic milling (trochoidal toolpaths) with a 10 mm 5 flute carbide end mill.<\/p>\n\n\n\n

Semifinishing: <\/strong>6mm ball end mill (scallop height 0.02mm).<\/p>\n\n\n\n

Finishing (grooves\/slot): <\/strong>1.5mm miniature carbide end mill (7flute, necked reach).<\/p>\n\n\n\n

Ratchet feature: <\/strong>0.5mm tapered ball end mill (0.15mm corner radius programmed).<\/p>\n\n\n\n

Internal throughhole: <\/strong>Gun drilling (2.0mm diameter, 120mm depth \u2013 L\/D ratio 60:1) followed by carbide reamer.<\/p>\n\n\n\n

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Step 3: Machining Process (5Axis Simultaneous of CNC Machining)<\/h3>\n\n\n\n

Operation  Tool  Parameters  Result:<\/strong><\/p>\n\n\n\n

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  1. Face & turn OD  CNMG 432 insert (turning)  200 SFM, 0.1mm\/rev  15.8mm diameter<\/li>\n\n\n\n
  2. Drill center hole  1.8mm carbide drill  4,500 RPM, 0.025mm\/rev  Pilot hole<\/li>\n\n\n\n
  3. Gun drill throughhole  2.0mm gun drill (coolantfed)  8,000 RPM, 0.02mm\/rev  2.0mm +0.00\/0.02mm<\/li>\n\n\n\n
  4. Dynamic roughing  10mm end mill  8,000 RPM, 2,000mm\/min  80% material removed<\/li>\n\n\n\n
  5. 5axis handle finishing  6mm ball end mill  12,000 RPM, 1,500mm\/min  Handle surface RA 0.8\u00b5m<\/li>\n\n\n\n
  6. Rectangular slot (reduction tab)  1.5mm end mill (7flute)  18,000 RPM, 400mm\/min  2.5mm \u00d7 3.0mm \u00b10.008mm<\/li>\n\n\n\n
  7. Ratchet feature  0.5mm tapered ball (0.15mm rad)  22,000 RPM, 200mm\/min  0.15mm root radius retained<\/li>\n\n\n\n
  8. Ream final throughhole  2.0mm carbide reamer  2,000 RPM, 0.1mm\/rev  2.0mm +0.005\/0.000mm<\/li>\n<\/ol>\n\n\n\n
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    Step 4: Post Machining Heat Treatment & Finishing<\/h3>\n\n\n\n

    Heat treat:<\/strong> Age hardening to H900 (480\u00b0C \/ 900\u00b0F for 1 hour, air cool). Achieved hardness: 44 HRC (target 43\u201346 HRC).<\/p>\n\n\n\n

    Surface finishing:<\/strong><\/p>\n\n\n\n

    Electropolishing: 30 minutes in an electrolytic bath to remove a 0.01mm layer, resulting in a bright, smooth (RA \u2264 0.2\u00b5m), and passivated surface. This eliminated any burrs from the 0.5mm ratchet tool.<\/p>\n\n\n\n

    Passivation: <\/strong>Subsequent citric acid bath to ensure chromium oxide restoration (per ASTM A967).<\/p>\n\n\n\n

    Inspection:<\/strong><\/p>\n\n\n\n

    CMM (Coordinate Measuring Machine) for full 5axis dimensional inspection.<\/p>\n\n\n\n

    Vision system for 0.15mm ratchet root radius verification.<\/p>\n\n\n\n

    Optical comparator for slot tolerance.<\/p>\n\n\n\n

    Surface roughness profilometer (RA 0.18\u00b5m achieved).<\/p>\n\n\n\n

    Requirement<\/strong><\/td>Specified<\/strong><\/td>Flow Wing<\/strong> Result<\/strong><\/td>Pass\/Fail<\/strong><\/td><\/tr>
    Material<\/td>174 PH H900<\/td>174 PH H900 (44 HRC)<\/td>Pass<\/td><\/tr>
    Slot tolerance<\/td>\u00b10.010 mm<\/td>\u00b10.006 mm (Cpk 1.8)<\/td>Pass<\/td><\/tr>
    Through-hole diameter<\/td>2.0mm +0.01\/0.00 mm<\/td>2.003 mm average<\/td>Pass<\/td><\/tr>
    Ratchet root radius<\/td>\u2264 0.18 mm radius<\/td>0.152 mm radius<\/td>Pass<\/td><\/tr>
    Surface finish (functional)<\/td>RA \u2264 0.4 \u00b5m<\/td>RA 0.18 \u00b5m (electropolished)<\/td>Pass<\/td><\/tr>
    Lead time (200 units)<\/td>4 weeks<\/td>3.5 weeks<\/td>Pass<\/td><\/tr>
    Unit cost (vs. 3-piece assembly)<\/td>\u2264 25%<\/td>38% reduction<\/td>Pass<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
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    CNC Machining<\/strong> the Result:<\/h2>\n\n\n\n

    Cost savings: <\/strong>38% lower per unit cost compared to the previous 3 component assembly ($48 \u2192 $30 per instrument).<\/p>\n\n\n\n

    Lead time reduction: <\/strong>From 8 weeks to 3.5 weeks for 200 units (factory to sterile ready).<\/p>\n\n\n\n

    Quality improvement<\/strong>: Slot positioning tolerance \u00b10.006mm vs. previous \u00b10.08mm (13\u00d7 more precise). No rework or scrap in production run.<\/p>\n\n\n\n

    Reliability: <\/strong>Zero field failures after 24 months (3,500+ surgical uses). No crevice corrosion, no weld fractures (there are no welds), and the electropolished surface cleans faster in sterile processing.<\/p>\n\n\n\n

    Clinical feedback:<\/strong> “The single piece instrument feels more solid, engages the pedicle screw with zero play, and the ergonomic handle reduced surgeon hand fatigue by approximately 40%.” \u2013 Lead Spine Surgeon, University Hospital Munich<\/p>\n\n\n\n

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    Client testimonial:<\/h2>\n\n\n\n

    “Flow Wing Metal transformed a three part welded assembly into a monolithic 5 axis CNC machining masterpiece. The 0.15mm internal corner on the ratchet feature \u2013 achieved with a 0.5mm end mill \u2013 is the reason we chose them over five other CNC machining shops. They understand medical quality.”<\/p>\n\n\n\n

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    5Axis CNC Machining 17-4 PH Stainless Steel Surgical Instrument: At Flow Wing Metal, we specialize in CNC machining for high-precision […]<\/p>\n","protected":false},"featured_media":2151,"menu_order":0,"template":"","cxb_product_category":[20],"cxb_product_tag":[212,223,221,222,224,210,211,195,215,199,213,216,217,208,209,214,77,219,65,218,220],"class_list":["post-2155","cxb_products","type-cxb_products","status-publish","has-post-thumbnail","hentry","cxb_product_category-cnc-machining-services","cxb_product_tag-5-axis-cnc-machining-service","cxb_product_tag-cnc-machining-aluminum-frame","cxb_product_tag-cnc-machining-electrical-parts","cxb_product_tag-cnc-machining-medical-parts","cxb_product_tag-cnc-machining-metal-components","cxb_product_tag-cnc-machining-parts","cxb_product_tag-cnc-machining-service","cxb_product_tag-cnc-machining-small-parts","cxb_product_tag-cnc-machining-tiny-parts","cxb_product_tag-cnc-metal-parts","cxb_product_tag-cnc-milling-aluminum","cxb_product_tag-cnc-milling-service","cxb_product_tag-cnc-turned-components","cxb_product_tag-custom-cnc-machining-service","cxb_product_tag-low-volume-cnc-machining","cxb_product_tag-machining-steel-parts","cxb_product_tag-oem-cnc-machining","cxb_product_tag-plastic-cnc-machining","cxb_product_tag-precision-cnc-machining","cxb_product_tag-stainless-steel-cnc-machining","cxb_product_tag-steel-cnc-machining"],"blocksy_meta":[],"_links":{"self":[{"href":"https:\/\/tigweldingaluminum.com\/fr\/wp-json\/wp\/v2\/cxb_products\/2155","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/tigweldingaluminum.com\/fr\/wp-json\/wp\/v2\/cxb_products"}],"about":[{"href":"https:\/\/tigweldingaluminum.com\/fr\/wp-json\/wp\/v2\/types\/cxb_products"}],"version-history":[{"count":10,"href":"https:\/\/tigweldingaluminum.com\/fr\/wp-json\/wp\/v2\/cxb_products\/2155\/revisions"}],"predecessor-version":[{"id":2553,"href":"https:\/\/tigweldingaluminum.com\/fr\/wp-json\/wp\/v2\/cxb_products\/2155\/revisions\/2553"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/tigweldingaluminum.com\/fr\/wp-json\/wp\/v2\/media\/2151"}],"wp:attachment":[{"href":"https:\/\/tigweldingaluminum.com\/fr\/wp-json\/wp\/v2\/media?parent=2155"}],"wp:term":[{"taxonomy":"cxb_product_category","embeddable":true,"href":"https:\/\/tigweldingaluminum.com\/fr\/wp-json\/wp\/v2\/cxb_product_category?post=2155"},{"taxonomy":"cxb_product_tag","embeddable":true,"href":"https:\/\/tigweldingaluminum.com\/fr\/wp-json\/wp\/v2\/cxb_product_tag?post=2155"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}