FAQs
Answers to your technical and commercial questions about bigHead fastening products.
Answers to your technical and commercial questions about bigHead fastening products.
Yes. Any component between the screw head and the collar adds to the installation stack thickness and must be included in the calculation.
Ensure the screw length meets or exceeds the required minimum engagement: L + installation stack + 1.2 mm (if fastening from the Head side).
The examples in this guide show how to calculate it.
Yes. bigHead offers custom collar options – including closed, sighted, length variant, and hybrid options. We can help you choose the optimal collar customisation for your application.
The screw will bottom out against the closed end, deforming or damaging the bigHead. This is considered misuse and may result in product failure.
The clearance allowance scales with thread diameter and pitch to maintain sufficient deformation protection. Larger threads require greater tip clearance.