#10-24 UNC thread: 4.83 mm × 24 TPI

Threads › #10-24 UNC

#10-24 UNC is a UNC thread: 4.83 mm major diameter, 24 TPI (1.058 mm pitch), 60° form. Tap drill 3.8 mm.

Standard	UNC
Major diameter	4.826 mm (0.19″)
Pitch	24 TPI (1.058 mm)
Thread angle	60°
Minor diameter, bolt	3.53 mm
Minor diameter, nut	3.68 mm
Tap drill	3.8 mm
Usual class	2A bolt, 2B nut

Minor diameters worked out from the basic profile: major Ø − 1.22687 × pitch (bolt) and − 1.08253 × pitch (nut).

Open #10-24 UNC in Benchsmith Add to order list

Measure it

Bolt: Measure across the crests of the bolt with the caliper jaws. Worn bolts read 0.1 to 0.3 under.

Nut or tapped hole: Measure across the tops of the threads inside the nut or hole with the inside jaws. That is the minor Ø. Worn or oversize holes read a little over.

Same diameter, other pitch

#10-32 UNF32 TPI (0.794 mm pitch)

Close in size, won't mate

3/16 BSWØ4.76 mm, 24 TPI
M5Ø5 mm, 0.8 mm pitch
#8-36 UNFØ4.17 mm, 36 TPI
M4Ø4 mm, 0.7 mm pitch

One size up or down

#8-32 UNCØ4.17 mm (down)
#12-24 UNCØ5.49 mm (up)

Got a bolt and no idea what it is? Measure the outside Ø and type it into Benchsmith → Find → Thread.