Maybe this helps for now. Search these threads (no pun indented) as there is much more information to help. Look for Roland Jakel's posts.
by DEFAULT :
- the fastener takes the diameter of the smallest hole reference.
- the head/nut diameter is 1.7x the diameter of the smallest hole reference
- the separation test diameter is 2x the diameter of the smallest hole reference
All the diameter numbers can be changed manually after selecting the references.
I would propose that the fastener diameter you select should be the stress diameter. See published tables.
It is up to you how you change the head/nut and separation diameters. Defaults are reasonable for most purposes.
Sensibly, the fastener diameter cannot be bigger than the hole. The nut/head diameter cannot be smaller than the hole(s), the separation test diameter cannot be smaller than largest hole.
For a bolt, both holes the same diameter:
For a screw:
Separation diameter, what it looks like and where it is :
Spring stiffness that keeps the opposing separation diameters annular regions apart:
http://portal.ku.edu.tr/~cbasdogan/Courses/MDesign/course_notes/Joint_Stiffness.pdf
Fastener head/nut diameter what it looks like and where it is
If you use contact then there is no longer any purpose for the separation springs and they are not created. The contact provides the stiffness.
Hint. We tend only to use the separation springs when building a model. These are linear and therefore quick but there are many reasons why the results could mislead. For the complete model we always use contact which is non-linear and takes longer.
bfn
