The information on this page gives some best practice guidlines about proper joint design for the POP NUT ™.
Making the Hole in the Parent Material
The hole for POP NUT ™ must be square to the parent material. Holes drilled or punched on an angle can cause premature tool mandrel wear issues. Back side burrs or punch tabs should also be removed so the back side flange can form symmetrically and flat. A tapered parent material will cause tool mandrel wear issues.
Grip Range
The parent material thickness must be within the grip range of the POP NUT ™. Softer materials such as plastic allow the POP NUT ™ to expand in the hole reducing grip range. Testing is required to determine the optimum drip in plastics.
Backside Clearance
If the POP NUT ™ will be used in a tube, extrusion or other application that is closed on the back side, there must be sufficient space for the POP NUT ™ to fit in the hole before installation.
Installation Tool Access
The POP NUT ™ tool must have perpendicular access to the parent material. If the tool is held on an angle premature mandrel wear occur. Special nose pieces can be developed to avoid obstacles.
The Mating Part
The mating part should have a hole size that is smaller than the POP NUT ™ head diameter to assure contact with the head. If alignment tolerances are needed then the hole in the mating material should be slotted so the parent material remains in contact with the head of the POP NUT ™.
The POP NUT ™ Joint and Mating Screw
The ideal POP NUT ™ joint is one where the mating part is non-rotational and contacts the head of the POP NUT ™. The tighter the screw gets the tighter the POP NUT ™ becomes. The mating screw can be up to grade 5 or metric class 8.8. If the mating screw has a prevailing torque locking device, it is best to choose a hex body POP NUT ™. The mating screw should thread through the POP NUT ™ by 2 threads.
