what is the difference between fixed and
floating fasteners?
The primary difference between fixed and floating fasteners is their function and the way they
control alignment during assembly:
• Fixed fasteners
They are used to precisely locate one part relative to another; their position is "fixed" by mating a
fastener (like a bolt or pin) through a clearance hole in one part and threading or fixing it into a
precise location (such as a threaded hole) in the mating part. This demands tighter tolerance and
precise alignment, making them suitable where accurate positioning is critical
• Floating fasteners
They mainly serve to hold or join parts together and allow slight movement within the
clearance holes of both parts. Both parts have clearance holes (unthreaded and slightly larger
than the fastener), and the fastener (such as a bolt with a nut) "floats" within these holes, so
strict alignment is not required. This allows for looser tolerances and easier assembly where
precise positioning is less important
Example
In a fixed fastener assembly, a bolt passes through a clearance hole in one plate and
threads into a tapped hole in the other plate, fixing their alignment.
In a floating fastener assembly, a bolt passes through clearance holes in both plates and is
tightened with a nut; the bolt's location "floats" within the holes