in the model I use measurment tool get material thickness is 2mm, I use this model to creat drawing, and get thickness dimension 1.5mm, is it a bug?
Hard to say. Why not post your files so we can look at what you're seeing?
how to post file?
Please see How can I attach a file to a forum post?
sounds like you have settings with DECIMALS to look at.
Check the settings in your Measure tool. I'd guess the decimals are set to zero.
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