Making screw caps and nuts

[ivla]

Making a simple screw cap with "thread" primitive.

Make the helicoid thread object:

Extrude upper non-flat face by Y axis, not by normal (!!!) :

Repeat with lower face:

Flatten those faces by Y:


Inset both faces:


Scale (enlarge) both of them radial by Y axis

Use "Absolute scale" to set size of upper face:

And repeat with the lower (with same size by X & Z):

Select upper and lower faces and use "bridge"

Select whole oblect and "Invert" it:

Select faces on lower end of object and extrude it by Y axis

Unlesect all, select faces in the inner surface:

"Dissolve" it

All done.
Below I cutted the cap in half to show what's inside it:


Same process can be used for making nuts, but it requires to modify the initial oblect (dissolve some faces in its lower - smaller - end) and does not require last steps (extrude & dissolve).

Modifying thread primitive for making nut:

Select lower - smaller - face, then "Select more" (by presing "+" key):

"Dissolve" it:

Select those two points and "Connect" it:

"Connect" another two points:

Primitive is ready.
To make nut extrude upper and lower faces etc., as shown above.