How are drill bits sized?

Typical drill bits have markings somewhere on the shank above the threads. It’s small, but it usually has the drill-bit diameter stamped into the metal; the number is written in fractions. For example, the markings may read: 1/4-inch, 3/6-inch or 25/32.

What are the 3 types of sizes of drill bits?

Types of Drill Bits

  • 1/16″
  • 5/64″
  • 3/32″
  • 7/64″
  • 1/8″
  • 9/64″

How do you calculate drill size?

I quickly calculate proper tap-drill diameters using this simple formula. Tap-drill diameter equals nominal diameter minus thread pitch. For example, drill size for a 3/8-16 thread is 0.375 0.0625 (pitch) = 0.312 in. in diameter, and for a 10-32 thread, the drill diameter is 0.190 0.032 = 0.159 in.

What do the numbers on a drill bit mean?

As mentioned at the beginning of the article, the numbers on a drill represent the amount of torque the tool can apply to an object (such as a screw) or for hole drilling. The numbers usually range from 1 to 20 (or more) with 1 representing the least amount of torque and 20, the greatest.

What size is a 5 mm drill bit?

Drill Bit Hole Diameters
Metric Size Fractional Size
5 mm .1968 7/32
6 mm .2362 15/64
7 mm .2756 1/4

How many drill bit sizes are there?

Number and letter gauge drill bit sizes Number drill bit gauge sizes range from size 80 (the smallest) to size 1 (the largest) followed by letter gauge size A (the smallest) to size Z (the largest).

How many types of bits are there?

The four main bits you’ll come across or need for your walls or DIY projects are a masonry bit, a wood bit, a tile bit, and a twist bit. Drill bits from different brands will look slightly different but they will still feature the same main characteristics to help you distinguish between them.

What are the most common drill bit sizes?

In the United States, standard drill bits are most often sized in fractional, 1/64th inch increments, commonly ranging from 1/16th inch up to one inch. If you need a larger hole, you can opt for a spade bit or hole saw bit.

What is formula of size of hole?

This formula is pi * radius squared * height = volume. This can predict the volume of a post hole, a golf hole or a hole you’re digging.

What is the formula for tapping?

In/Min = RPM divided by # of Threads / in.