Surgical instrument machining
Forceps, scissors, jaws and ratchets — mating faces, serrations and edge condition before passivation.
Open instruments →SOLUTIONS · MEDICAL DEVICE
Medical Device — The Failure Mode Is a Burr You Cannot See or Clean
On a medical part the defect that matters is usually not the dimension that is out. It is a burr on an edge the patient or the cleaning process will meet — inside a lumen, on a jaw mating face, at the root of a thread. That burr is not a cosmetic issue and it is not removable by inspection: it is a cleanability and residue problem, and sometimes a tissue-interaction problem. Three things drive the tool decision here — the feature is small, the edge is the function, and the material is often chosen for the body rather than for the machine. HENTRY reviews the print against those three, then quotes the geometry that gets there.
WHO THIS IS FOR
Shops where the edge is the product
- Surgical instrument manufacturers — forceps, scissors, needle holders, retractors, jaw and ratchet assemblies
- Orthopaedic and trauma suppliers — bone screws, plates, pins, and joint component features
- Catheter, cannula and minimally invasive device builders — shafts, hubs, tips and lumen parts
- Typical stocks: 316L and 17-4PH stainless, Ti-6Al-4V, cobalt-chrome, nitinol, PEEK and other engineering polymers
If your part is a general machined component with no patient or cleanroom contact, the General Mechanical hub is the faster route. This hub assumes the edge, the lumen or the surface will be judged against a cleaning or biocompatibility requirement.
CORE APPEAL
Three conditions that make ordinary holemaking insufficient
Most medical parts are not difficult to cut. They are difficult to finish, because the last 0.1 mm is where the acceptance decision lives:
- Scale. Features are small enough that tool deflection, not tool wear, sets the result. A drill that is rigid enough for the diameter may be too long to enter the feature at all, so the process is designed around reach as much as around cut.
- The edge is the function. A jaw that does not mate, a scissors blade with a rolled edge, a screw thread with a torn flank — these fail functionally and they fail inspection. Edge condition is specified, so it has to be produced, not inspected in.
- Material chosen for the body. 316L, cobalt-chrome and nitinol are selected for corrosion, wear or superelasticity, not for machinability. Work hardening, low thermal conductivity and springback all show up as burr and as dimension drift, and the tool geometry has to absorb them.
This hub stays at requirement level. Instrument edge strategy, implant thread and surface routes, and lumen drilling detail live on the three subpages — they are not restated here.
PROCESS SNAPSHOT
Tool map for medical device parts
| Need | Common path | HENTRY entry |
|---|---|---|
| Small bores and pin holes | Micro drill with a controlled entry; step or pilot first where the surface is curved | Micro Carbide Drills |
| Slots, serrations and jaw forms | Micro end mill geometry matched to the corner radius the print actually calls | Micro End Mills |
| Stainless and cobalt-chrome holes | Carbide with edge prep and coolant aimed at work hardening rather than at speed | Carbide Drill for Stainless |
| Precision bores after drilling | Ream where the print needs roundness and a defined surface, not just size | Carbide Reamer |
| Contoured and radiused forms | Ball-nose or custom geometry where a standard cutter cannot reach the form | Ball Nose End Mills · Custom End Mills |
SUB-SOLUTIONS
Choose the page that matches your part
Orthopaedic implant machining
Bone screws, plates and joint features in titanium, cobalt-chrome and stainless — thread form and surface condition.
Open implants →Cannula & lumen machining
Cannula, hypotube and catheter shafts — micro drilling, lumen burr and thin-wall deflection.
Open cannula work →WHEN TO LEAVE THIS HUB
Use a different scenario when the job changes
- Small holes with no cleanliness or edge requirement — general micro drilling → Micro-Precision & Special hub.
- The alloy physics is the whole problem — titanium and cobalt-chrome heat and chip control without a device requirement → Difficult Materials hub.
- Housings and enclosures for equipment — instrument cases, carts, capital equipment frames → General Mechanical hub.
- Fluid-path parts with a pressure requirement rather than a patient requirement — pump and valve bodies → Hydraulic & Fluid Power hub.
RFQ CHECKLIST
What to send for a medical part review
- Drawing and revision, with the functional edge or lumen marked
- Material and condition — 316L, 17-4PH, Ti-6Al-4V, cobalt-chrome, nitinol, PEEK
- Feature schedule: Ø, depth, corner radius, thread form, surface callout
- The cleaning or passivation step that follows, and what it must not find
- Machine, holder, stickout and coolant — reach usually decides the tool before the diameter does
- Volume and whether a first-article or a capability sample is required
FAQ
Quick answers before you RFQ
Can a tool change really remove a burr, or is deburring always a separate operation?
Often the tool can prevent the burr rather than remove it, which is cheaper and more repeatable. Edge geometry, the direction of cut and the support behind the exit all change whether material shears or folds. Where the burr is unavoidable, it is planned as a defined step with a defined tool, not left to a hand operation that nobody can inspect.
Do you hold ISO 13485 or any medical device certification?
We do not publish a certification claim, and we will not imply one. If your quality system requires a specific approval or a documented process validation, state it on the RFQ and we will confirm what can and cannot be supported before quoting. Our published position on evidence is on Manufacturing & Quality Evidence.
Which materials are the hard ones here?
Cobalt-chrome and nitinol, for different reasons. Cobalt-chrome work-hardens and resists a clean shear, so edges tend to tear. Nitinol is superelastic, so it springs back against the tool and behaves nothing like stainless at the same feed. Both are quoted from the drawing with the alloy condition stated — a generic "stainless" note is not enough.
Can you produce the edge geometry, or only the hole?
Both, within the tool's reach. Serrations, jaw forms and radiused edges are cut with the tool geometry the print calls for; where a standard cutter cannot reach the form, the geometry is quoted as a custom tool. The instrument subpage covers the edge strategy in detail.
Where does the general micro-drilling guidance live?
On the Small-Diameter Holemaking page under Micro-Precision. This hub covers what a device requirement adds on top of that; it does not repeat the drilling fundamentals.
ENGINEERING QUOTE
Send the print with the functional edge marked
Primary tooling entries for this hub: micro carbide drills, micro end mills, carbide reamers and custom geometry for jaw and lumen forms. Quality-system requirements are confirmed before quoting, never assumed.