Cut Tool question

[MotoMoto]

Good afternoon all, I am trying to cut out the width of my door but it keeps extending past my door, because hammer seems to want to only cut on grids. Is there anyway I can get it to cut the exact width of my door? (Pictured attach for context) I am super new to hammer so sorry if this seems like a dumb question.

 

[Sonoma]

have you tried decreasing the size of the grid? you can also use the [ and ] buttons to increase and decrease the size of the grid