Metallics TX1234 12-14 x 3/4 in. 5/16 Hex Head Metal to Metal Self-Drilling Screws - #3 Drill Point - All-Weather - Each

The #3 drill point on the TX1234 is rated for a panel thickness of 0.110 to 0.210 inch. That covers metal panel into steel purlin or bar joist framing in that range. If your substrate is thinner than 0.110 inch, a #1 or #2 point drills faster without stripping; heavier than 0.210 inch and you need a #4 or #5 point.

No. It is a Type BSD metal to metal self-drilling screw without a washer, so there is no bonded EPDM seal under the head. It is intended for attaching standing seam roof clips and wall or roof panels to steel framing where the clip or panel makes the seal. For an exposed fastener roof panel that has to seal at the screw head, order a version with a bonded washer instead.

The TX1234 is 3/4 inch under the head. With the #3 point rated for 0.110 to 0.210 inch of steel, that leaves ample shank for the panel or clip plus point drill-out. Add up your clip base and panel thickness first: the point has to fully clear the far side of the steel before the threads start pulling, or it will strip. If your stack-up is thicker, step to a longer length rather than forcing this one.

A 5/16 hex driver. The head is a hex head with hex drive, measuring 0.305 to 0.312 inch across the flats and 0.34 inch across corners, with a head height of 0.139 to 0.155 inch. A standard 5/16 magnetic nut setter in an impact or screw gun is what crews run these with.

The TX1234 carries a zinc/all-weather coating, which is what makes it suitable for exterior metal building work rather than interior-only fastening. Note there is no washer under the head, so weather performance at the hole depends on the panel or clip detail, not on the fastener sealing itself.

They ship in a jar with a 50-each order minimum, so 50 pieces is the smallest quantity. Other sizes and quantities are available by request if a job needs a different length or a bulk count.

Thread is 14 threads per inch on a 12-14 diameter, conforming to SAE J78-2013, with head dimensions to ASME B18.6.3-2010. Steel is AISI 1016-1024, case hardened to Rockwell C32-40, with a minimum torsional strength of 92 lb-in. It is listed ARRA compliant and Buy American compliant, with multiple countries of origin.

Drill time runs about 2.5 seconds through a 1 mm thick plate. Minimum torque values are the same for stainless and steel self-drill screws, so crews do not need to change gun settings when switching between them. The steel here is hardened to Rockwell C32-40 with 92 lb-in minimum torsional strength, so back off the clutch before you snap heads on thicker framing.