Tap Drill Size Chart

M52 x 5 Tap Drill Size

Tap drill

47 mm 1.8504 in

Use a 47 mm drill (1.8504 in) for 77.0% thread.

The drill size for a M52 x 5 tap is 47 mm (1.8504 in). If you are wondering what size drill bit a M52 x 5 tap needs, that is the one: it leaves 77.0% of thread, which is the figure standard tap and drill charts are built around. Below are the other holes you might want for this size - a larger drill for tough material, the form-tap hole, and the clearance holes for the bolt that goes in.

Every drill for M52 x 5

Tap drills and clearance drills for M52 x 5 (Metric coarse, 5 mm pitch). Percent of thread is the figure stored for each drill, which reproduces from the major diameter and pitch of M52 x 5.
Use Drill Decimal in mm % thread
Standard tap drill Cut tap, general use (D - P) 47 mm 1.8504 47.00 77.0%
Inch substitute Closest inch drill if you have no metric set 1-27/32″ 1.8438 46.83 79.6%
Hard material Stainless, tool steel, anything that fights the tap 48 mm 1.8898 48.00 61.6%
Form (roll) tap Theoretical 49.79 mm - starting point, check your tap maker's chart 50 mm 1.9685 50.00 —

Clearance holes for a M52 x 5 bolt

A clearance hole is not tapped. It is the hole in the part the bolt passes through, so it is always larger than the thread.

Clearance holes for M52 x 5 per ISO 273. Clearance depends on the bolt diameter alone, so every M52 thread shares these figures.
Fit Hole mm Hole in
Fine 54.00 2.126
Medium 56.00 2.2047
Coarse 62.00 2.4409

M52 x 5 dimensions

Nominal dimensions for M52 x 5. The basic internal minor diameter is the hole a 100% thread would start from, which is why no tap drill is ever that small.
Dimension Inch mm
Major diameter 2.0472 52.00
Basic internal minor diameter 1.8341 46.59
Pitch 0.1969 5.00
Thread designation M52 x 5

What the hole looks like

Cross-section of a M52 x 5 tapped hole, drawn to scale The drilled hole is 47 mm, 1.8504 inches or 47.00 millimetres across. The tap cuts outward from that wall to the major diameter of 2.0472 inches. A 100 percent thread would reach in to the basic minor diameter of 1.8341 inches, shown as a dashed line; the difference is why this drill gives 77.0% of thread. major 52 mm drill 47 mm · 47 mm dashed = 100% thread at 46.59 mm
M52 x 5 in section, to scale. The accent line is the thread the tap cuts from a 47 mm hole; the dashed line is where the crest would sit at 100% thread. The gap between them is the 23.0% of thread this drill leaves behind.

Work out a different hole for M52 x 5

Pre-filled with M52 x 5. Change the material, the tap type, or which drills you actually own, and it picks the closest real drill and tells you the percent of thread you end up with. The tables above are the published figures and do not depend on this.

The general-purpose target

Tap type
Drills you have

Best drill you have, cut tap, 70% target

47.5 mm1.8701 in69.3% thread

Theoretical hole 47.45 mm

One size down, deeper thread1-55/64″ 1.8594 in · 73.5%

One size up, easier tapping1-7/8″ 1.875 in · 67.4%

For comparison, the published chart drill for M52 x 5 is 47 mm at 77.0% thread.

Notes on M52 x 5

Only pitch in the data
M52 x 5 is the only pitch this chart lists at 52 mm, so there is no fine or coarse alternative to confuse it with.
What the standard drill gives you
47 mm leaves 77.0% of thread (D - P). That is in the normal 65-80% band most shop charts aim for.
Stainless, tool steel and other tough material
48 mm opens the hole to 61.6% engagement. Less material for the tap to cut means less torque and less heat, at the cost of some thread depth.
Using a form (roll) tap
A form tap displaces metal instead of cutting it, so it needs a larger hole: 50 mm, against a theoretical 49.79 mm. Treat that as a starting point and check your tap maker's chart.
This size is usually bored, not drilled
At 52 mm, holes this big are normally bored or thread-milled rather than drilled and tapped. The 47 mm figure is here so the numbers are complete and so you can check a hole you already have; on a machine you would single-point or thread-mill the thread and bore the hole to size.
Closest inch size
1-1/2-6 is the nearest inch thread by diameter (38.1 mm against 52 mm). It is a planning reference only. The two are not interchangeable: the pitches differ, and a bolt from one will not run into a hole tapped for the other.

Related sizes

Next size up and down

Closest inch size

1-1/2-6 1-11/32″ · 1.3438 in · 34.13 mm · 72.1% 38.1 mm major against 52 mm

Not interchangeable. 1-1/2-6 is the nearest size by diameter, nothing more. The pitches differ, so a 1-1/2-6 fastener will not run into a M52 x 5 hole and forcing one will strip both.

Guides for tapping M52 x 5

Longer reads on the decisions behind the numbers above.

All guides →

M52 x 5 tap drill: common questions

What size drill bit do I need for a M52 x 5 tap?
A 47 mm drill, 1.8504 in. That leaves 77.0% of thread, which is the standard chart figure for M52 x 5.
What is the drill size for a M52 x 5 tap in inches?
The 47 mm tap drill measures 1.8504 in. If you only have inch drills, 1-27/32 in (1.8438 in) is the closest, giving 79.6% thread.
What drill should I use for M52 x 5 in stainless steel?
Use 48 mm instead of 47 mm. It leaves 61.6% of thread rather than 77.0%, so there is less material for the tap to cut and less chance of snapping it.
What is the clearance hole for an M52 x 5 bolt?
For a medium fit, 56 mm per ISO 273. A clearance hole is not tapped; the bolt passes straight through it.
A 4 × 6 in card with the drills for this size.