Custom Vacuum Chamber Manufacturer — Build to Print or to Spec

A custom chamber is a compromise between what the process needs, what the material will do under welding, and what can actually be machined afterwards. The earlier those three are reconciled the cheaper the chamber is, so we prefer to be involved at the drawing stage rather than at the quotation stage.

How a custom chamber project runs

We start from either a customer drawing or a performance specification. If it is a specification, the first step is agreeing the material, the sealing family and the surface treatment, because those three decisions determine the achievable vacuum and the cost far more than the wall thickness does. Once agreed, the sequence is weld, stress relieve, machine, electropolish, leak test, bake, inspect.

Why the sequence matters more than any single step

Welding distorts, so the sealing faces have to be machined after welding. Machining leaves coolant and chips, so the surface has to be cleaned and polished after machining. Polishing leaves a smeared layer if done mechanically, so electropolishing follows. Electropolishing leaves hydrogen and water on the surface, so a bake follows. Each step exists because of the one before it, and skipping one moves the problem rather than removing it.

Sizing and handling

Our gantry machining envelope is 12 m × 4 m × 2 m, so a large chamber can be machined in a single setup. That matters because a chamber machined in two setups has a datum change in the middle, and the flange positions either side of that datum will not agree.

What you get with the chamber

A dimensional report from CMM inspection, a helium leak test record with the method and detection limit stated, surface finish measurements, material certificates and weld procedure documentation. For semiconductor and research customers this package is part of the deliverable, not an optional extra.

When a custom chamber is the wrong answer

If the requirement is a standard small chamber for routine high-vacuum work, a standard product will be cheaper and faster. Custom fabrication earns its cost when the geometry, the size or the vacuum level is outside what standard products cover — which in practice means large chambers, unusual port layouts, or UHV and bakeable construction.

What we control in-house

304 / 316L stainless steel and 6061 / 5083 aluminium fabrication
Clean-environment TIG welding with full penetration and no micro-porosity
Helium mass-spectrometer leak testing to 1 × 10⁻⁹ mbar·l/s
In-house electropolishing and passivation — not subcontracted
Chamber bake-out to 150–400 °C for UHV outgassing control
Precision-machined ISO-KF, ISO-K and CF (ConFlat) flanges
Zeiss CMM verification to ±0.02 mm across large work envelopes
12 m gantry CNC machining — 12 m × 4 m × 2 m envelope
SEMI-referenced documentation and inspection protocols

Frequently asked questions

How much does a custom vacuum chamber cost?

It depends almost entirely on the vacuum level, the size and the material rather than on the shape. A UHV chamber with electropolishing, all-metal seals and a full test package costs several times a high-vacuum chamber of the same volume in elastomer-sealed construction. We quote against a defined specification rather than a volume.

What is the largest vacuum chamber you can make?

Our gantry machining envelope is 12 m × 4 m × 2 m, which sets the practical limit on a single-piece chamber. Larger vessels can be built in sections, but the joints then become part of the vacuum design.

How long does a custom chamber take?

A small to medium chamber is normally weeks rather than months. Large UHV weldments take longer because of the sequence — welding, stress relief, machining, polishing, leak testing and bake-out cannot be compressed without losing the result.

Can you work from a performance specification rather than a drawing?

Yes. If you give the required vacuum level, the internal volume, the port requirements and the service temperature, we can propose the material, the sealing family and the surface treatment, and quote against that. Agreeing those three early is what keeps the cost predictable.

Do you supply one-off chambers?

Yes. We build both one-off custom chambers and repeat production under long-term supply agreements. A representative example is a Japanese semiconductor equipment manufacturer for whom we now supply more than 50 chambers a year.