The flat end of the Tapcon drill bit is on the opposite end of the carbide tip and is the end of the bit that is inserted into the installation tool kit. This flat end of the Tapcon bit is aligned flat side out when inserted into the installation toolkit so that a set screw can be tightened against it, holding the Tapcon bit tightly in the installation tool.
Any carbide tipped masonry bit that is manufactured to meet ANSI standard B212-15-1994 can be used for drilling holes in masonry that Tapcon masonry anchors are installed in. If the installation toolkit is being used then the special Tapcon bit must be used.
Carbide tipped bit must be used for drilling the hole into the base material for the Tapcon screw. The quality ANSI standard carbide tips are brazed onto the end of the bit to ensure long life and consistent hole tolerance. Older style or less expensive carbide-tipped bits have the carbide soldered on. Solder has a lower melting point than the brazing method and will not last as long.
The Tapcon drill bit that is used depends on the diameter of the Tapcon screw being installed. The 3/16” Tapcon requires the use of 5/32” diameter bit, and the 1/4” Tapcon requires a 3/16” diameter bit.
The length of the Tapcon bit to use must be long enough to ensure that the hole drilled into the base material is 1/2” deeper than the Tapcon screw will penetrate the base material and will allow the Tapcon screw to meet minimum embedment depth of 1”. The designated length of each drill bit is measured as an overall length. The 5/32” Tapcon drill bit comes in three lengths and the 1/4” Tapcon drill bit comes in five lengths. The drilling depth of each length of the drill bit is 1-1/2” less than the overall length.
|Tapcon Diameter||Diameter x Length||Drill Depth|
|3/16”||5/32” x 3-1/2”||2”|
|5/32” x 4-1/2”||3”|
|5/32” x 5-1/2”||4”|
|1/4”||3/16” x 3-1/2”||2”|
|3/16” x 4-1/2”||3”|
|3/16” x 5-1/2”||4”|
|3/16” x 6-1/2”||5”|
|3/16” x 7-1/2||6”|
Each and every different length of Tapcon screw requires a specific length bit to be used to meet minimum hold depth requirements. The length of the bit is the same whether it’s a flat Phillips countersunk head or a hex washer head. The chart for each length of Tapcon and the correct corresponding bit that must be used is included below:
|Length of Tapcon||Length of Tapcon Bit|
The Tapcon drill bit must be used in a hammer drill, and the hammer drill must be set in the hammer and rotation mode. Hole tolerance is critical when installing Tapcon concrete screws. To produce the quality hole required, the Tapcon bit must be used in a rotary hammer drill. Unlike the standard rotary drill that requires the bit to cut the material to produce a hole, the hammer drill pulverizes the material with the hammering motion and the rotation removes the debris via the fluted section of the drill bit.
There are other styles of bits that can be used for drilling holes in the base material for the Tapcon concrete screws. They must meet ANSI Standard B212-15-1994, be the correct diameter and length for the Tapcon being installed and must be used in a hammer drill that is set in the hammer and rotation mode.
As with any anchoring project, it is important to keep safety in mind and follow instructions carefully. Always remember to wear safety goggles, handle all tools with extra care and follow all technical specifications. This article is meant to serve only as a basic explanation of concrete fasteners. Always refer to manufacturer's instructions or consult a contracting expert during any anchoring project.