You can use the Edit Frame for "Flat" the edges & faces...
Free to you to deselect reselect this Flat aera for move it any where you want (not shown here but it's trivial)
So the trivial :) You see the 3D view but the manipulations are inside the Front or Left view! ;)
More easy of course!
Concept of modeling :) my very few Shortcuts (i have no memory) B=Bridge P= Split K=Subdivide
Split rectangle
Bridge 2 faces
Kill face(s) here one
Subdivide
Shell
Subdivide
Separate all
View Points
MovePoints
Boolean Union
Separate Face(s)
Extrude (or move face(s) + Bridge = only between 2 faces !
Join or Boolean Union
SubDivide
Cancel
Separate face(s) etc...
...
SubDivide
List seems long but it's very speedy! :) And it's a solid so 3D Printable!
The "Extrude Method" always on an subdivided object !
as it's difficult to select the extremity face a little trick
select lateral face - then rectangular selection on the extremity face - then click the lateral face ;)
= extremity face selected :)
Extrude as you want
Subdivide
(multiple extrude faces can be made but depending of faces' situation - impossible for some cases )
Just for the fun : use the SsPlit function for speed modeling! :) (P = Ssplit)
The first time click an edge - Mirror enabled
Move & Create 2 lines on the volume
Click an edge
Right Click for recall the Ssplit function
Move & Create 2 lines on the volume
Click an edge
etc...
then extrude Positive or Negative faces
and as always it's difficult to select "tiny faces" - Select a Big face then Little face(s)
then re-click the Big face for deselect it! ;)
and extrude them
etc...
As volume is now complex Subdivide can't work easilly on all the volume!
So volume must be trimed in some parts for have have some partial subdivisions
Use of the Bridge function for transition between a curvature perimeter and a straight perimeter
so a perfect solid at the end!
It's just a tool for make something very speedy who will difficult to make in other way !
Free to you to make real or imaginative things with it! :)
And all is 3D Printable because it's a solid!
It's slighty different than normal modelisation as result is "hypothetical" !
You have not the total control on the result in measure... else make some tests following that you wish...
ok i have the same by Copy/ Move & killing the internal Top Bottom faces...Join(front faces hidden/shown)
And for the Extrude without separate will be also fine in killing internal Top Bottom & Vertical faces...
All that is some tricky! :)