Thunderbolts – Multi Purpose Fixing Bolt – Hex Head

Thunderbolts – Multi Purpose Fixing Bolt – Hex Head is the original self-tapping masonry anchor, and it has been getting builders out of awkward fixing jobs for a long time. The bolt cuts its own thread into the base material as it goes in. The substrate effectively becomes the nut. Same principle you already trust with wood screws and self-tappers on steel, just applied to brick, block, stone and concrete.

No plug, no resin, no waiting about. You drill a hole with a standard masonry bit, run the bolt in with a socket or spanner, and that is the job done. The hex head gives you a proper grip for a ratchet or impact driver, which matters when you are fixing into something dense and the bolt needs a bit of persuasion.

Where Thunderbolts Hex Head Bolts Get Used

Fixing timber battens, sole plates and studwork to masonry is the classic one. Door frames, window frames, handrails, brackets, steel angles, signage, racking, lighting columns and fence posts are all fair game. Because the thread bites directly into the material, you can fix closer to an edge and closer to the next fixing than you could with an expanding anchor. Less cracked brickwork, fewer sulky words.

Another point in their favour: they come out again. Take one out, drop it back in the same hole if you need to, or use it somewhere else. For temporary works, hoardings, scaffold tie-ins on short-term jobs and anything you might need to dismantle later, that is a real advantage over resin anchors.

Choosing the right size

The range runs from 8mm up to 16mm diameter, in lengths from 60mm to 200mm. As a rough guide, the bolt needs to pass through whatever you are fixing and then go into the masonry by at least 40mm to 50mm for a decent hold. Add the thickness of the fixture to the embedment depth and you have your minimum length. Going a size up in diameter gives you more load capacity, but the hole gets bigger too, so check you have the right drill bit and a drill that can cope with it.

Hole depth should be around 10mm to 15mm deeper than the bolt will penetrate, so dust and debris have somewhere to sit instead of jamming the thread halfway. Clear the hole before you drive, because a dusty hole makes for a hard install and a weaker fix.

These are sold in boxes from 10 up to 100 depending on the size, so you can grab a small box for a single job or stock up for a larger contract. Bulk pricing is where the savings stack up, particularly on the common 10 x 100mm and 12 x 100mm sizes.