What size drill bit do I need for a 1/4-28 tap?
7/32″
US Tap and Drill Bit Size Table
| Tap | Fractional Drill Bit | Number Drill Bit |
|---|---|---|
| 1/4″-28 | 7/32″ | 3 |
| 5/16″-18 | 17/64″ | – |
| 5/16″-24 | – | – |
| 3/8″-16 | 5/16″ | – |
What drill is the proper tap drill for a 1/4-28 UNF screw?
titanium nitride ( TiN)
| FRACTIONAL SIZES UNC and UNF | ||
|---|---|---|
| Nominal Size Tap | Recommended Tap Drill | |
| 1/4-20 1/4-28 | 7 3 | 0.2010″ 0.2130″ |
| 5/16-18 5/16-24 | F I | 0.2570″ 0.2720″ |
| 3/8-16 3/8-24 | 5/16 Q | 0.3125″ 0.3320″ |
What size drill bit do you use for 1/4 inch tap?
The best overall size drill bit for 1/4″ 20 UNC tap thread is a #7 drill bit, the measurement being 13/64” (0.203″diameter).
What size hole do I drill for 1/4-20 tap?
13/64″ 7
US Tap and Drill Bit Size Table
| Tap | Fractional Drill Bit | Number Drill Bit |
|---|---|---|
| #12-24 | 11/64″ | 16 |
| 1/4″-20 | 13/64″ | 7 |
| 1/4″-28 | 7/32″ | 3 |
| 5/16″-18 | 17/64″ | – |
What size is a number 29 drill bit?
9/64″
| To Tap This Size Screw Or Bolt: | Use This Drill Bit: | (Closest Fractional:) |
|---|---|---|
| 8-36 NF | #29 | 9/64″ |
| 8-40 NS | #28 | – |
| 3/16-24 NS | #26 | – |
| 10-24 NC | #25 | 5/32″ |
What does NS stand for on a tap?
NS means special thread. Pitch Diameter is the basic dimension of a screw, threaded hole, or a tap the diameter of an imaginary cylinder, the surface of which passes through the thread where width of thread and space between threads are identical. This cylinder, of course, would be a cone for tapered taps.
What size hole do you drill for a 1/4 bolt?
4130). The chart below shows drill sizes up to 1 inch in diameter….
| Screw Size-TPI | Recommended Hole Diameter | Drill Bit Size |
|---|---|---|
| 1/4-20 | 0.2280″ | #1 |
| 5/16-18 | 0.2900″ | L |
| 3/8-16 | 0.3580″ | T |
| 1/2-13 | 0.4531″ | 29/64″ |