CNC Tapping Kovar

Looking for reliable CNC Tapping Kovar? VT machining manufactures Kovar parts to tight tolerances and consistent quality. Kovar is matched thermal expansion for glass/ceramic seals, so the process is set up specifically for the material.

CNC Tapping Kovar at VT machining
CNC Tapping Kovar — produced in-house at VT machining

CNC Tapping Capability for Kovar

  • Metric & UNC/UNF threads
  • Rigid synchronized tapping
  • Thread depth control
  • Form and cut taps

Kovar Material Data

Kovar — typical properties, quoted for Kovar (ASTM F15)
Density8.36 g/cm³
Tensile strength517 MPa
Yield strength (0.2%)340 MPa
Hardness140–160 HV
Melting point1450 °C
Thermal conductivity17.3 W/m·K
Thermal expansion5.1 (30–200 °C) ×10⁻⁶/K
Electrical conductivity3.5%
Machinability (C36000 = 100%)35%
Grades we runKovar / ASTM F15, Alloy 42, Alloy 52

Published typical values for Kovar (ASTM F15). Other grades in the family differ — the certificate supplied with your order carries the actual heat-lot figures.

Machining Kovar — what actually causes trouble

Sealing surfaces must stay clean. Parts destined for glass-to-metal seals are degreased and handled without bare hands after final machining.

How CNC Tapping Kovar Works

Rotating multi-flute cutters remove material as the Kovar 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 Tapping Kovar

CNC Tapping Kovar — 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.

Working with Kovar

Kovar offers a useful combination of properties: it is matched thermal expansion for glass/ceramic seals. 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.

Secondary Operations & Finishing

We complete Kovar 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.

CNC Tapping Tolerances & Surface Finish

For CNC Tapping, 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 Tapping Kovar

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 Kovar. If you send your model early, we will return practical DFM feedback before you commit to production.

CNC Tapping Quality & Inspection

Consistent quality comes from disciplined process control. Critical dimensions on Kovar 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.

Applications of CNC Tapping Kovar

CNC Tapping of Kovar 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 Tapping Kovar

Ordering Kovar 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 Kovar

Three representative CNC Tapping Kovar 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.

Heat sink base

Material
Kovar
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.

Manifold block

Material
Kovar
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.

Robot end-effector bracket

Material
Kovar
Size
180 × 90 × 30 mm
Key callouts
Bore pair concentric within 0.02 mm, weight reduction pockets
Batch
120 pcs

Pockets ganged so wall thickness never drops below 2 mm at the load path.

Finishing Options for Kovar

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 Tapping Kovar

  • 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 Kovar 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 Tapping

Other Processes for Kovar

Send the drawing, the Kovar 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

Can VT machining make custom Kovar parts to my drawing?

Yes. Kovar Kovar machining is made to order from your CAD/2D drawing. Share your geometry, material grade, tolerance and quantity and we will confirm feasibility, lead time and pricing.

What surface finish is achievable on Kovar with CNC Tapping?

Surface finish on Kovar is controlled to your specification; we confirm the achievable Ra against your callout.

Which industries use CNC Tapping Kovar parts?

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

What material thickness or size range suits CNC Tapping Kovar?

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

How clean are the edges produced by CNC Tapping on Kovar?

Machined Kovar edges are clean and to specification; edge-break or deburring is added when your drawing calls for it.

What tolerances can you hold for CNC Tapping Kovar?

Achievable tolerances for Kovar 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.