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Tight Flatness Condition

Tight Flatness Condition

Tight Flatness Condition

I am having an increased need for tighter flatness specs. Currently I have quite a few parts that are within 50 millionths flatness. I have been able to successfully measure these with an optical flat, but only when the surface finish is really good.

I have a new part coming that needs to be flat within 33 millionths. It will once again be hard to measure because of the polish we are able to produce here on this grade of material isnt as reflective as others. Has anyone found a nice system that is easier to read than an optical flat and cheaper than an interferometer?

Ryan M
Quality Engineer
3d Printer Hobbyist

RE: Tight Flatness Condition

I've lapped hydraulic pump/motor end caps to 35 millionth flatness and always used an optical flat.
I haven't heard of a better way to measure flatness in this range.


RE: Tight Flatness Condition

Our Perthen surface profilometer measures to 0.1 micron but that may not really be good enough since it's not quite 10% of your spec.


The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

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