sizes change when inverting model

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sizes change when inverting model

Post by snowand » Wed 03 Mar , 2010 13:37 pm

Hi All
When using Quickcam Pro Ver and opening an STL file the model size is shown
e.g. X=85 Y=125 Z=25
If I invert the model these sizes remain until I get to the "Set Cut Depth" screen... if I want to machine to the bottom of the model these sizes change to X=87 Y=127 Z=25. Why is this and how can I correct it???
many Thanks.... Snowand

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Re: sizes change when inverting model

Post by Denford Admin » Wed 03 Mar , 2010 15:10 pm

Without looking too deeply into it, I'm guessing that inverting the model is adding 1mm onto each side of the original.
This will be so that everything is preserved when the 3D shape is inverted and sliced...the software has to slice open the bottom of a model when inverting, as most models are fully-closed shapes.
Adding a small border gives the new inverted shape a top surface to work from.
The model itself should still be the same size when produced.

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