Guides / For Machine Shops

Should Your Shop Run Anodising In House?

September 27, 2026

A shop that machines cosmetic aluminium eventually asks whether to bring anodising in house. There is no universally correct answer, because the two paths trade different costs for different risks, and the right one depends on your volume and your customer mix more than on either option being objectively better.

What in house buys you

Direct control over the variable that causes the most disputes on a keyboard job: colour consistency across a two piece case. When anodising is under your own roof, you set batching policy yourself, you can hold a part back rather than run it in a dye lot you are unsure of, and a colour problem gets diagnosed in your own building instead of over email with a third party.

It also removes a step from your lead time chain. Finishing at an outside vendor is consistently the phase where schedules slip, as covered in keyboard case lead time, because your job queues behind everyone else’s on their line, not yours.

What it costs you

Capital and floor space, first. Tanks, rectifiers, ventilation, racking and effluent treatment are a real investment before the line finishes a single part, and effluent treatment in particular is an ongoing regulatory and disposal cost, not a one time build.

Volume utilisation, second. An anodising line has fixed running costs whether it processes ten parts or ten thousand. A shop without steady finishing volume across its whole customer base, not just keyboard work, will run the line under capacity, which erases much of the savings that justified building it.

Skill, third. Anodising is a chemistry and process control discipline, not a machining discipline. A shop that is excellent at cutting cosmetic aluminium and mediocre at anodising has usually made its parts worse, not better, by insourcing.

What outsourcing buys you

No capital tied up in tanks. A specialist finisher runs anodising as their whole business, which usually means tighter process control, a wider colour library, and access to specialty finishes like PVD or cerakote that would not justify a dedicated line for keyboard volumes alone.

It also lets a shop scale finishing capacity up or down with demand, which matters for a business with a lumpy order book like group buy work.

What it costs you

A dependency you do not fully control. Your finishing lead time is now someone else’s queue, your colour consistency now depends on someone else’s batching discipline, and a colour miss shows up as your problem to the customer even though the process happened elsewhere.

The fix is not to avoid outsourcing, it is to manage the relationship the way you would manage any critical supplier: a small number of finishers you use repeatedly rather than the cheapest quote each time, a documented batching instruction on every purchase order, and a physical golden sample that both sides sign off before a production run. This is exactly what colour repeatability with an anodiser actually depends on, and it works whether the tanks are down the hall or across town.

A reasonable middle path

Plenty of shops split the decision by finish type. Decorative Type II colour work, which is the bulk of keyboard case volume, runs in house because the chemistry is simpler and the equipment cheaper to justify. Type III hardcoat, PVD and other specialty finishes go to a dedicated outside vendor, because the volume rarely justifies a second line and the process control is harder to get right in house.

There is no version of this decision that removes risk entirely. There is a version that matches the risk to what your shop is actually good at, and that is the one worth building toward.

Frequently asked questions

Keep reading

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• The Overage Conversation Every Shop Should Start