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Single Point Threading Technical Chart

Material HB/Rc Speed (SFM) First Pass Depth
Tool Diameter
Uncoated ALTiN+ .040-.050 .060-.092 .120-.152 .180-.232 .290-.362 .373+
Cast Iron 160 HB 75-200 200-550 0.003 0.004 0.005 0.007 0.008 0.009
Carbon Steel 18 Rc 75-200 200-450 0.003 0.005 0.006 0.007 0.008 0.009
Alloy Steel 20 Rc 75-200 200-425 0.003 0.004 0.005 0.006 0.007 0.008
Tool Steel 25 Rc 75-175 175-300 0.002 0.003 0.004 0.005 0.006 0.007
300 Stainless Steel 150 HB 75-175 175-350 0.003 0.003 0.004 0.005 0.006 0.007
400 Stainless Steel 195 HB 75-210 130-420 0.003 0.004 0.005 0.006 0.006 0.007
High Temp Alloy
(Ni & Co Base)
20 Rc 50-130 130-300 0.002 0.003 0.003 0.004 0.005 0.005
Titanium 25 Rc 50-100 120-275 0.003 0.003 0.004 0.005 0.006 0.007
Heat Treated Alloys
(38-45 Rc)
40 Rc 50-100 100-200 0.002 0.002 0.003 0.004 0.004 0.005
Aluminum 100 HB 75-250 250-750 0.004 0.005 0.007 0.008 0.010 0.011
Brass, Zinc 80 HB 75-300 250-650 0.003 0.005 0.006 0.007 0.008 0.009

Parameters are a starting point based on machinability rating at hardness listed.
Check machinability rating of the material to be machined and adjust First Pass Depth.

Helpful Formulas and Information

PITCH = 1 / TPI

TPI = Threads Per Inch

ACME Thread Depth = Pitch x 0.5

Stub ACME Thread Depth = Pitch x 0.3

NPT Pipe Thread Depth = Pitch x 0.76

Internal 60° Thread Depth = Pitch x 0.54

Feed Rate = Pitch x Number of Thread Starts

Minimum Depth per Pass should not be less than 0.0003

Threads not ending in a relief need at least one thread pitch length of pullout

Make sure fee rate calculation does not exceed the maximum feed rate of the machine