yes ro you convert to subdivs...
you can also convert to subdivsion -
its not needed to smooth polygon, mostly it destroy your modell or it makes to mutch of polygon counts...
1, menue edit/convert(polygon to subdivision)
than maya makes your modell very smooth and a bit thinner.
2, press right mouse BUtton/
there you choose //Polygon//
than its showing green polygon mesh over the smooth subdiv-surface of the model,
3, than you switch again with pressing right mousebutton and select //edges//
4, than you select the edges showing @ this place where you need hard edges
5, than you choose menue - Subdivs/fullcreaseVertex
and Maya makes you there a perfect edge.
with this method the rest of your modell is perfect.
you can also afther again covert //Subdivs to polygon// or what ever you need...
CU
https://lab.palindrom.ch
https://www.achermann.cc
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