Reference Sphere Sizes

[[Ni...]]

Good Morning,

I am wondering what everyone uses to qualify your probes.

I was under the impression that all probes 1.0mm and under should be using an 8mm reference sphere to qualify and probe 1.5mm and above can use a 30mm reference sphere to qualify.
Most of our 1.5mm and 1mm are X 40mm in length.

Wondering if this is how it should be or if i should just move all of my 1mm to the 30mm reference sphere?


Thank You

[[DW...]]

You cannot move your smaller probes to the 30mm sphere - they will shank out if you try to do 180 degree sphere coverage. Sure you can adjust it to be less than 180 degree coverage, but then you aren't qualifying the entire probe. Keep doing what you are doing. Also for your smaller probes (<1.5mm), set your probing dynamic force to 20%.

[[Ri...]]

Get a 25mm Reference Sphere instead. It will qualify 0.3mm probes as well.

[[To...]]

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Why?

[[DW...]]

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This was a quick generalization of a personal preference. I should have omitted it from my answer. Here is a snippet about probing force and dynamics from the Zeiss Sensor Cookbook for reference (VAST/VAST gold/VAST XT/ VAST XT Gold/VAST XTR).

20230719_094626.jpg

[[To...]]

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Thanks for the info.

[[Wo...]]

I only use 8mm sphere on probes that will shank out on the 30mm.

As long as the shank is long enough, I'm using 30mm sphere even for 0.3mm probes with no issues with sigma values.

Wojciech

[[Da...]]

Just to share my experience when doing qualification of 0.3 mm ruby on 25 mm reference sphere - sigma value was low, but diameter of ruby was measured bigger. Of course, because the shaft was touching, it just happened that ruby was concentric to the shaft I guess.