How To Check and Measure Flatness

Don Bailey inspecting the part that was ground in the How to grind fast video for flatness.

[OmarRios]

What you are actually measuring there is Parallelism, not Flatness.
For Flatness, you would need to mount the surface in question down on 3 o 4 blocks or towers to isolate the surface. Then turn 180° your probe to take measurements.

[ObelixCMM]

That part could be out of tolerance for flatness.With concaved surface on the bottom there would be no rocking motion.Flatness is not related to condition of other surface like in this example. It is form of one surface and should be measured independently. I'm surprised that large mfg. like Suburban Tools are showing this as way of measuring flatness.

[annafertiti]

it is informative, but is kind of hard to see what where your measuring because your hand are on the way. maybe a if you position the camera in a different angle would help.

regards,

[rohanmehta]

SIR I THINK WHAT YOU SHOULD TO USE WAS PARALLELISN AND NOT FLATNESS

[nikhilk]

which surface need to butted on surface table, the surface which we measure or opposite for flatness inspection?

[sanketchikalge]

what is that instrument you are using???

[danielbrand]

What is the indicator and the needle tool called?

[nghieu]

sir, what if the part just require for parallelism, and you have a part with a concave or convex surface it just parallel it self, does that part are acceptable?

[Mech.Masters]

What is the difference between Flatness & Parallelism in terms of measuring method?

[meocats]

wouldn't it be faster with an optical flat?