CNC Drilling Invar

Looking for reliable CNC Drilling Invar? VT machining manufactures Invar parts to tight tolerances and consistent quality. Invar is ultra-low thermal expansion, so the process is set up specifically for the material.

CNC Drilling Invar at VT machining
CNC Drilling Invar — produced in-house at VT machining

CNC Drilling Capability for Invar

  • Hole position ±0.05 mm
  • Depth-to-diameter to 10:1+
  • Peck and through-coolant cycles
  • Spot, drill, ream sequencing

Invar Material Data

Invar — typical properties, quoted for Invar 36 (FeNi36)
Density8.11 g/cm³
Tensile strength450–590 MPa
Yield strength (0.2%)275 MPa
Hardness130–160 HB
Melting point1427 °C
Thermal conductivity10.5 W/m·K
Thermal expansion1.2 (0–100 °C) ×10⁻⁶/K
Electrical conductivity2%
Machinability (C36000 = 100%)25%
Grades we runInvar 36, Super Invar 32-5, Alloy 42, Alloy 46

Published typical values for Invar 36 (FeNi36). Other grades in the family differ — the certificate supplied with your order carries the actual heat-lot figures.

Machining Invar — what actually causes trouble

The low expansion is the whole point, so machining stress is the enemy. Rough, stress-relieve at 315–425 °C, then finish — otherwise the part moves after it leaves the machine.

How CNC Drilling Invar Works

Rotating multi-flute cutters remove material as the Invar workpiece is driven through programmed tool paths on 3-, 4- or 5-axis machining centres. Climb milling, step-over and depth-of-cut are set so chip load stays in the ideal band for the alloy.

Every job begins from your CAD model or 2D drawing. Fixturing and tool paths are planned so the most critical dimensions are produced in the most rigid, repeatable setup. Critical dimensions are checked on the first part and monitored through the run.

Achievable Tolerances for CNC Drilling Invar

CNC Drilling Invar — achievable tolerances
FeatureStandardPrecision
Linear dimension (< 100 mm)±0.05 mm±0.010 mm
Linear dimension (100–300 mm)±0.10 mm±0.025 mm
Hole diameter (reamed)H9H7
True position of hole pattern±0.10 mm±0.025 mm
Flatness over 100 mm0.05 mm0.015 mm
Perpendicularity0.10 mm0.020 mm
Surface finish, as machinedRa 1.6 µmRa 0.4 µm

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 Drilling Tolerances & Surface Finish

For CNC Drilling, dimensional and positional tolerances around ±0.01 mm are routine, tightening toward ±0.005 mm on precision setups. Surface finish on machined faces typically falls in the Ra 0.4–1.6 µm range depending on tooling and pass strategy.

Final tolerances are governed by the material's behaviour, wall thickness and overall stiffness. We give honest DFM feedback if a callout would be costly or better achieved another way.

Design Tips for CNC Drilling Invar

A few design choices make a real difference to cost and quality. Generous internal radii, sensible pocket depth-to-width ratios and avoiding very thin unsupported walls all reduce cost and improve accuracy in Invar. If you send your model early, we will return practical DFM feedback before you commit to production.

Working with Invar

Invar offers a useful combination of properties: it is ultra-low thermal expansion. Those characteristics shape how we approach milling — from tool and parameter selection to work-holding and coolant.

If your application is sensitive to alloy condition, we agree the specification in writing and document it. Stock is sourced from reputable suppliers so what you order is what you receive.

CNC Drilling Quality & Inspection

Consistent quality comes from disciplined process control. Critical dimensions on Invar parts are checked in-process and verified at final inspection using calibrated instruments and, where required, CMM measurement. Full documentation — dimensional reports, mill certs, FAIR — is available when your programme needs it.

Secondary Operations & Finishing

We complete Invar components with the secondary steps your drawing calls for. We arrange heat treatment, surface treatment, marking and assembly as needed. Tell us the final spec and we will plan the full route so parts arrive ready to use.

Applications of CNC Drilling Invar

CNC Drilling of Invar supports parts across aerospace, medical, automotive, electronics, semiconductor, energy and general industrial sectors. We scale from one-off prototypes to ongoing production while holding the same quality.

How to Order CNC Drilling Invar

Ordering Invar parts is straightforward. Provide the drawing, material, quantity and any certification needs. Our engineers reply — in English — with feasibility, pricing and a realistic lead time, usually within one business day.

Parts We Have Run in Invar

Three representative CNC Drilling Invar jobs, with the callouts that actually drove the process plan. Yours will differ — these are here so you can judge whether your part is in our range before you spend time on an RFQ.

Manifold block

Material
Invar
Size
120 × 60 × 45 mm
Key callouts
Cross-bore intersection ±0.05 mm, ports G1/8", leak-tested to 10 bar
Batch
80 pcs

Deburred internally with a brush tool; a burr at a cross-bore is what fails the leak test.

Heat sink base

Material
Invar
Size
200 × 100 × 8 mm
Key callouts
Fin thickness 1.2 ±0.05 mm, base flatness 0.03 mm
Batch
500 pcs

Fins cut with a slotting cutter in one pass to avoid the deflection a step-over leaves.

Vacuum chamber flange

Material
Invar
Size
Ø180 × 20 mm
Key callouts
Knife-edge seal Ra 0.4 µm, bolt circle ±0.05 mm
Batch
60 pcs

Sealing face finished last, then handled in gloves and bagged straight off the machine.

Finishing Options for Invar

Finishing options available with this material
FinishThickness / effectWhy it gets specified
Deburr / edge break0.05–0.3 mmAll parts unless the drawing says otherwise
Bead blastRa 1.6–3.2 µmUniform matt finish, hides tool marks
Laser markingPart number, lot code, data matrix
Free — no sign-up

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.

Open the 3D + 2D Builder

What We Need to Quote CNC 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 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 Quote

Frequently Asked Questions

Does CNC Drilling Invar require dedicated tooling?

Most Invar machining work uses standard cutting tools and CNC programs; dedicated fixtures are made only when geometry or volume requires them.

What tolerances can you hold for CNC Drilling Invar?

Achievable tolerances for Invar machining depend on the alloy, geometry and feature size. Milling holds positional and dimensional tolerances to around ±0.01 mm, tighter with precision setups. Exact figures are confirmed against your drawing callouts.

Which industries use CNC Drilling Invar parts?

CNC Drilling Invar parts are used across aerospace, medical, automotive, electronics, semiconductor and general industrial sectors — anywhere precise Invar components are required.

Why is Invar a good choice for CNC Drilling?

Invar is ultra-low thermal expansion, which makes it well suited to CNC Drilling. We tune the process to the alloy so the finished Invar machining part meets your dimensional and functional requirements.

What is the typical lead time and minimum order for CNC Drilling Invar?

CNC 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.

What material thickness or size range suits CNC Drilling Invar?

We machine Invar across a broad size range; share your part envelope for confirmation.