Metallics 3410CTT Carbon Steel Tap Taper Type 3/4-10 (1pc)

Taper type. A taper (sometimes called a starting) tap has a long chamfered lead of several threads, so it eases into the hole and self-aligns. It will not cut full threads to the bottom of a blind hole, so if you need threads right down to a closed bottom, follow it with a plug or bottoming tap in the same 3/4-10 size.

It's a carbon steel tap, which handles mild steel, aluminum, brass, and plastics fine at hand-tapping speeds with cutting oil. For hardened or stainless stock, or for repeated production tapping in a drill press, a high speed steel tap will hold its edge longer. For occasional field work rethreading hanger holes or strut, carbon steel is the normal choice.

For 3/4-10 UNC the standard tap drill is 21/32 inch, which gives roughly 75 percent thread engagement. Drill square to the surface, keep the tap lubricated, and back it off every turn or two to clear the chips.

Yes, as long as the original thread is 3/4-10 coarse. The tap reforms the internal thread in a coupling, nut, or drop-in anchor that has been dinged or filled with concrete slurry. Verify the existing thread is 10 TPI and not a fine 3/4-16 before running it, since forcing the wrong pitch will ruin the part.

One tap per pack, supplied in a pouch. If you are kitting multiple crews or want a spare on the truck, order the quantity you need rather than expecting a set.

Metallics part number 3410CTT. The designation reads out as 3/4-10 thread, Carbon steel, Taper Type, which is handy when you are matching it against other sizes in the same series.