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Hi @Anonymous
Although I don't see "yellow plate" in the drawing you attached, I recreated it, well maybe something similar.
You can use Subobject selection technique to edit, move in your case, upper face of the plate.
Set UCS to World.
Press and hold Crtl key ob keyboard and click on upper face of the plate, you will see red dot - Subobject grip.
Now select this grip and move your mouse up, from keyboard entry distance - 2.7 and hit Return:
Upper face move 2.7 units up and you get 5.7 thickness (3.0+2.7=5.7)
For reference look >>>>here<<<<
Hi Maxim,
One more question:
On the white frame on the left side, there is an o-ring groove on the top surface. How to select these "subtracted" surface, and delete this o-ring groove? Thanks~
Switch to "Shaded with edges" Visual Style for better visibility.
Set Subobject Selection Filter to Face:
Now pick on groove bottom surface to select it:
Now look for "red dot" grip in the center of the groove, select it and adjust face position using object snap to 3D Vertex here:
See the result in attachment