TolAnalyst can consider the clearances resulting from fixed and floating fastener assemblies when it computes the worst case tolerance conditions.
When you locate and constrain parts in assemblies using fasteners, the Float fasteners and pins option uses the clearances between the holes and fasteners to increase the worst-case minimum and maximum result. Each part can move in an amount equal to the radial distance between the hole and fastener.
For fixed fastener assemblies, float applies to the part with clearance holes only. For floating fastener assemblies, float applies to both parts. You can also apply float to parts that are located and constrained using hole–pin mating schemes.
| Fixed Fastener Assemblies |
Floating Fastener Assemblies |
 |
 |
| Bolts pass through one part and are threaded into another. |
Bolts pass through both parts and are bound with nuts. |
When to Consider Using Fastener Float
-
If
the sole function of the clearance holes is to provide room
for the fasteners, and the clearances are used to aid and
provide adjustment to the assembly, using fastener float is generally not recommended.
- If the clearance holes are also used to locate the parts, and you need to know the adverse
effects the clearances allow, using fastener float is recommended.