Metallics JTSF29V 10 x 1-1/4 in. Flat Head Phillips Tapping Screws - Steel Zinc - Each

Yes, if the countersink matches the head. The JTSF29V is a flat head screw with a head width of 0.333 to 0.362 in. and a head height of 0.098 to 0.116 in., so an 82 degree countersink in sheet metal or a factory-countersunk device bracket takes it flush. In a plain punched hole with no countersink, the head will stand proud by about the head height.

Type A is for pre-punched or pre-drilled holes only. The JTSF29V has a gimlet point, which starts in an existing hole and forms its own thread as it drives, but it will not cut through unpunched steel the way a self-drilling (Type TEK) screw does. With 12 threads per inch, the coarse spaced thread is aimed at thin gauge sheet, wood, and plastics rather than heavy plate. If you are fastening into solid steel with no hole, choose a self-drilling screw instead.

A #2 Phillips driver. The recess on the JTSF29V measures 0.198 in. diameter, 0.124 in. deep, with a 0.032 in. recess width, so a #2 bit seats fully. Using a #1 or #3 bit in that recess is how you cam out and strip heads on a long run.

They ship in a jar of 500 count, and 500 is the order minimum, so a jar is the smallest buy. Each jar weighs 3.75 lbs. Metallics does offer other sizes and quantities in the JTSF line by request.

Zinc plated carbon steel is a mild corrosion finish, fine for dry interior work, conditioned spaces, and enclosures. The JTSF29V is AISI 1016-1024 steel with a zinc finish, not stainless, so for exterior exposure, wet locations, or anywhere subject to washdown or coastal air it will eventually rust. Use a stainless or coated exterior-rated fastener in those spots.

The JTSF29V is flagged compliant for both Buy American and ARRA in the manufacturer's data, with country of origin listed as China. On federally funded work, submit the compliance flag along with the origin to your specifier, since different programs treat fasteners differently.

Both the thread and the overall dimensions are built to ASME B18.6.4, with the dimensional callout as ASME B18.6.4-1998. That is the governing spec for tapping screws, so the head, recess, and thread will interchange with any other B18.6.4 #10 Type A flat head Phillips screw. One caveat from Metallics: dimensions for #9 diameter screws in the JTSF line are independent of ASME B18.6.4.

The JTSF29V is heat treated to Rockwell C28-38 with a minimum torsional strength of 48 lb-in. That is the standard case-hardened range for a tapping screw: hard enough to form threads in sheet steel, and the 48 lb-in figure is the floor before the shank twists off. Drive it with a clutch or a low-torque setting rather than running an impact driver flat out.