I understand that the width of a cut will not be the width in CAD due to finite line width. My nozzle is 0.4 mm. When I cut/print a circular hole with a .4mm width my hole is usually about 0.5mm smaller. What I don’t understand is when I cut a slot the width is actually larger than that in its cad drawing.(i.e. a 4.5mm slot becomes 4.64mm, a 5.5mm slot becomes 5.6)…why ?
First, the most important question: Measured based on the printed object itself?
Filament shrinks a tiny bit after printing. The printer should compensate for this as much as possible, but there is usually a margin of error of around 0.1 - 0.2 mm unless it has been calibrated. However, more information is needed at this point: If you create a 4.5 mm hole in CAD, it is initially also a 4.5 mm hole in the slicer, so I assume you are referring to the printout itself?
A little tip: pictures are particularly helpful in such cases!
If you know, for example through test printouts and calibration, how much your printer is off, you can compensate for this with this option:
However, if your holes are completely off by +/- 0.5 mm, it seems more like a workflow problem, with an incorrect measurement somewhere. It is possible that the printer deviates that much, but it is very unlikely. You can also test this using the link above.
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As @RetroSharky mentioned, this indeed would be helped a lot by a screenshot.
Are you referring to a cut through an entire (part) of an object? Then, it is not surprising that the slot size increases. Both masses, to the left and right of the cut, shrink during cool down. So their outer walls move away from the cut, thereby making it larger.
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