Can't believe it's been over a month since my last post so thought I'd better put something up here. As I mentioned before I have been modelling some interesting props so thought I'd base a small tutorial on one of the aspects I come across multiple times, creating a hole within a mesh which is going to get a Turbosmooth modifier added so the need to keep the mesh clean is very important.
So we start off with a square box like this with 2 length and 2 width segments.
Next we add an Edit Poly modifier and select the center vertices in the middle (make sure you get both the top and bottom ones).
Then click on the Chamfer settings ensuring the Open Chamfer option is ticked and put in the value you wish to make the hole.
After this the mesh will be open on the sides of the hole so select the top 4 edges and shift click them down to create new faces and close the mesh.
If you now add the Turbosmooth modifier on and set iterations to 2 or 3 you can see the cut in the mesh which is nice and clean but the Turbosmooth has now smoothed the Box as well.
To get round this if you add another Edit Poly modifier before the Turbosmooth and chamfer the edges highlighted it will sharpen up the Box.
If you need the hole (in this case a circle) to be an exact size and perfect (the above will give a slightly square circle), then before you chamfer the edges and add the Turbosmooth modifier you need to make the below cuts in the mesh. I also use a circle with a step of 1. I then use this as the template where to move the newly cut vertices to (circle is scaled slightly smaller to show in illustration).
Now this technique can be used on a larger scale, multiple times and with different shapes as these below images of a drip grid show.
