News & insight

No. Reliable fastening with bigHead collar products does not depend on identifying a single ‘correct’ screw pairing. In most cases, there is a range of suitable screws that can be used successfully. Fastening performance is governed by internal thread loadability, thread engagement, and tightening control. When these factors are managed appropriately, variations in screw grade or property class are unlikely…

Adhesives and embedment interfaces primarily transfer clamp load and service loads into the parent structure. Testing the rotational loading resistance of the fastener installation is not the same as determining its capability to resist torque-tightening during assembly. You should base any evaluation of torque-tightening resistance on assembly trials with system representative specimens, not torque-off or torque-out testing of rotational-loading specimens.

No. Torque tables for standardised fastening elements may not account for the bigHead collar thread loadability. Maximum recommended tightening torques for the bigHead product must take precedence.

To use a higher-strength screw with a bigHead collar, you must be prepared to manage the assembly tightening through careful torque and preload control. This may involve VDI 2230 based bolt-calculations, depending on your application requirements. Our assembly guide will help you define torque and preload limits for our collar products.

No. There is no property class hierarchy for screw and collar pairings. Compatibility depends on preventing internal thread overstressing through engagement and tightening control, not on screw grade alone.

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.

Yes. Any component between the screw head and the collar adds to the installation stack thickness and must be included in the calculation.

The clearance allowance scales with thread diameter and pitch to maintain sufficient deformation protection. Larger threads require greater tip clearance.

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.

The screw will bottom out against the closed end, deforming or damaging the bigHead. This is considered misuse and may result in product failure.