frostic Wrote:when I create a cylinder with a radius of 15 by setting settings like in my image belowHi frostic. I think you didn't realize that you want the hole to have 15 units of DIAMETER instead of RADIUS.
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my hole that was made using 15 of the scale prints as a 30mm hole instead of 15.
To get it the way you want, you need to create a cylinder using a value of 7.5 units (half of the diameter.)