CHA-440-8 is a concealed-head self-clinching stud designed for permanent installation in aluminum sheets as thin as 0.062 in. (1.6 mm), providing a reusable #4-40 thread. It installs using a standard press into a blind hole with a minimum diameter of 0.172 in. and requires a minimum mounting depth of 0.112 in. The stud's head remains flush and concealed post-installation, leaving the opposite side of the sheet smooth and unmarred, supporting ingress protection requirements. It is recommended for aluminum sheets with hardness HRB 50 or HB 89 or less. The part conforms to the CHA series specification and is installed using the same method as other variants in the concealed-head stud family.
These studs ensure permanent mounting in metal sheets as thin as .062 in.
The fastener head is locked securely in a blind, milled hole and is able to handle substantial loads. The concealed-head feature allows the side of the sheet opposite installation to remain smooth.
Sheet preparation only requires a milled blind hole to the recommended minimum depth. Center-cutting end mills for hole preparation are available from PennEngineering. Installation of the concealed-head studs and standoffs is simple using a hollow anvil and solid punch. Place the head of the fastener in the hole and insert using any standard press. Displaced sheet metal flows smoothly around the head into the undercut.
| PennEngineering® | bisco industries | |
|---|---|---|
| Product Category | Studs | Studs |
| Product Number | CHA-440-8 | CHA-440-8 |
| Product Name | Concealed-Head Studs - Types CHA,CFHA,CHC,CFHC - Unified | Concealed Head Studs |
| Attachment | Pressed | Threaded |
| Shape | Round | |
| Design Units | English | English |
| Inch | # 4 | # 4 |
