With the inbuilt booltool addon. Why i can't punch a hole. The face facing correct. Removed double verts, scale rotation are 1 and 0,. Mesh has subsurf, solidify, mirror modifier. Im using 2.9 version after boolean with brush cant find the properties canvas to remove the brush. What missing or where im going wrong. Any suggestion.
1$\begingroup$ The edge split modifier of the cutter object makes it non manifold. Try to remove it. $\endgroup$– lemonSep 16, 2020 at 15:17
$\begingroup$ @lemon Thanks. where properties canvas menu disappear in 2.9. as shown in question $\endgroup$– atekSep 16, 2020 at 15:30
$\begingroup$ I used today 2.91 and after brush Difference "Canvas" part appered ... so I cant confirm your screen. (I used your blend as it is. Even with Edge Split modifier.) $\endgroup$– vkliduSep 20, 2020 at 20:51
Bool Tool fail
In provided file the Bool Tool, brush type Difference, works for me.
But your screen of "helmet" object looks differently. On screen Mirror modifier has unchecked Merge, so if you used it in this condition - Bool Tool failed.
Missing Canvas menu
This menu appears only when a brush is used. Than you can see properties menu when "Canvas" object is selected. BTW you have selected "Brush" object. So when boolean operation is used also here "Brush" properties appears when selected.