VT machining provides CNC EDM Drilling Invar for customers who need accurate, repeatable Invar components. Because Invar is ultra-low thermal expansion, we adapt the process to suit — controlling the variables that matter for this alloy.
Process Data for CNC EDM Drilling Invar
| Hole diameter range | Ø0.3-3.0 mm |
|---|---|
| Max depth-to-diameter | up to ~100:1 |
| Drilling speed, Ø1 mm | ~20 mm/min |
Shown for Invar 36, the most common Invar grade we see for CNC EDM Drilling. Typical values for Invar 36, Annealed; confirmed on the first part.
CNC EDM Drilling Capability for Invar
- Ø0.2–3 mm holes
- Deep aspect ratios
- Hardened-metal drilling
- Angled hole capability
Invar material properties, finishing options and grade notes are on our CNC Wire EDM Invar page.
How CNC EDM Drilling Invar Works
Material is removed from the Invar workpiece by controlled electrical discharges across a dielectric gap, with no mechanical contact. Flushing, on/off pulse timing and electrode/wire feed are set to balance speed against surface finish.
We start from your supplied geometry and tolerance scheme. The setup is designed to minimise re-clamping, which protects positional accuracy across features. A first article is verified against the drawing before the balance of the batch is released.
Achievable Tolerances for CNC EDM Drilling Invar
| Feature | Standard | Precision |
|---|---|---|
| Profile dimension | ±0.010 mm | ±0.002 mm |
| Internal corner radius | 0.15 mm | 0.05 mm |
| Taper control over 50 mm | 0.02 mm | 0.005 mm |
| Surface finish (skim passes) | Ra 0.8 µm | Ra 0.2 µm |
| Recast layer | 10 µm | 2 µm (fine skim) |
| Start-hole diameter | 1.0 mm | 0.25 mm |
| Workpiece hardness | no limit (conductive) | no limit (conductive) |
Standard is what a normal quotation assumes. Precision is available on nominated features and is priced separately, because it needs extra setups, in-process gauging and CMM verification. Call out only the features that need it — blanket-tightening a drawing is the single most common reason a quote comes back expensive.
CNC EDM Drilling Tolerances & Surface Finish
EDM holds tolerances to roughly ±0.002–0.005 mm with no cutting force on the Invar part, producing fine, controlled surface textures and sharp internal corners impossible to mill.
The tightest tolerances are reserved for the features your drawing flags as critical. Share your tolerance scheme and we will confirm what is realistic before quoting.
Design Tips for CNC EDM Drilling Invar
Small design adjustments often cut cost and lead time. EDM suits sharp internal corners, thin ribs and hardened Invar that cannot be milled; allowing a small corner radius where possible speeds the cut. If you send your model early, we will return practical DFM feedback before you commit to production.
Applications of CNC EDM Drilling Invar
Invar parts made this way are found throughout aerospace, medical, automotive, electronics and industrial equipment. Prototype, bridge and production volumes are all welcome.
Typical Invar Parts for CNC EDM Drilling
Illustrative examples of CNC EDM Drilling Invar parts and the callouts that usually drive the process plan. They show the kind of work that fits this process; they are not specific customer orders.
Extrusion die
- Material
- Invar
- Size
- 120 × 120 × 25 mm
- Key callouts
- Profile ±0.005 mm, internal corner R0.1 mm
- Batch
- 35 pcs
Cut in four skim passes; the first pass is speed, the last three are finish and accuracy.
Turbine blade fir-tree root
- Material
- Invar
- Size
- 40 × 25 mm section
- Key callouts
- Profile ±0.008 mm
- Batch
- 120 pcs
Held on a dedicated fixture so every blade in the set indexes identically.
Injection mould cavity rib
- Material
- Invar
- Size
- 0.25 mm wide × 8 mm deep
- Key callouts
- Width ±0.005 mm, VDI 21 finish
- Batch
- 45 pcs
Sinker EDM with a graphite electrode; a cutter that thin would break in the first pass.
No drawing yet? Build one in the browser.
Set the metal, dimensions and features, watch the 3D model update as you type, then switch to the 2D sheet to add dimensions and tolerances. Download it or send it straight to us with your RFQ.
What We Need to Quote CNC EDM Drilling Invar
- GeometrySTEP or IGES for the 3D model, plus a PDF drawing if you have tolerance callouts. A dimensioned sketch is enough to start.
- MaterialThe exact Invar grade and condition — temper, heat-treat state or hardness. If you are not sure, tell us the function and we will suggest one.
- QuantityPrototype count and the expected annual volume. Both change how the part is made and therefore what it costs.
- TolerancesWhich features are critical. Everything else runs to our standard tolerance, which is what keeps the price sensible.
- FinishSurface treatment, cosmetic requirements, and any faces that must be masked.
- DocumentsWhether you need a material certificate, dimensional report, FAIR or PPAP with the shipment.
Missing something from the list is not a problem — send what you have. We will come back with the specific questions rather than a generic form.
Other Metals for CNC EDM Drilling
Other Processes for Invar
Send the drawing, the Invar grade and the quantity. You get pricing, lead time and any DFM notes back — usually within one business day.
Request a QuoteFrequently Asked Questions
What is the typical lead time and minimum order for CNC EDM Drilling Invar?
CNC EDM Drilling prototypes for Invar can be produced quickly and scaled to series production. Send your drawing and quantity and we will advise lead time and any minimum order.
Does CNC EDM Drilling Invar require dedicated tooling?
Wire EDM needs no shaped tooling; sinker EDM uses a shaped electrode we produce in-house for your cavity.
Why is Invar a good choice for CNC EDM Drilling?
Invar is ultra-low thermal expansion, which makes it well suited to CNC EDM Drilling. We tune the process to the alloy so the finished Invar EDM machining part meets your dimensional and functional requirements.
What is CNC EDM Drilling Invar and how is it done?
CNC EDM Drilling Invar refers to fast-hole EDM drilling produces small, deep holes in hard metals, including starter holes for wire EDM. Applied to Invar — ultra-low thermal expansion — VT machining produces each part to your CAD drawing, selecting parameters from your tolerance, finish and quantity requirements.