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What are typical plating, anodize and grinding allowances?

Last updated 10 August 2026

Plating runs .0002 to .0005 per side for normal electroless nickel, anodize states a total coat of .0001 to .001 of which about half builds outward, and grinding leaves about .0025 per side.

The column that matters is not the window, it is what the process does to the part. A coating adds material, so it moves a bore and an outside diameter in opposite directions. Grinding removes it and runs the other way. Heat treat scales the part, so a bore and an outside diameter move together and which way is a question about the alloy rather than about the geometry.

Treat these as starting points and replace them with what your own vendors hold. The window is the part of this that is worth measuring: it comes straight out of your tolerance, and a shop that has never asked its plater for a real number is usually carrying a wider one than it needs to.

The table

ProcessWhat it does to the partPer side, typicalPer side, range this models
Platingadds material0.0002 to 0.0005 in0.0001 to 0.002 in
Anodizeadds material, about half of it above the surface0.0001 to 0.001 in0.0001 to 0.004 in
Grindingremoves material0.0025 in0.0005 to 0.03 in

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Process windows for tolerance walk-back. MIL-PRF-8625, MIL-STD-870. CC-BY-4.0, attribute to ctrlPlanner.

This is one characteristic. A real part has forty of them through five operations, and every one needs the same walk when the drawing revises. That is what ctrlPlanner does from a ballooned print.

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