Versadrive ImpactaTaps Technical Guide

Versadrive ImpactaTaps are designed for creating internal threads in correctly sized pilot holes using suitable impact or rotary tools. This guide covers material suitability, machine selection, material thickness, lubrication, adapters, best practice, recommended impact torque (ft-lbs) and rotary RPM.

The torque and RPM recommendations in this guide apply to UNC ImpactaTaps (including MAX inch sizes) and Metric Coarse ImpactaTaps.

Which Materials Can HMT Versadrive ImpactaTaps Be Used On?

Structural Steel

All HMT tooling in this category is suitable for the common grades of steel.

Hardened Steel

This category of tooling is not generally suitable for hardened steel applications.

Stainless Steel

Suitable for harder materials such as stainless steel when used at reduced RPM (rotary drilling machines) or higher torque settings (impact wrenches).

Non-Ferrous Metals

All HMT tooling in this category is suitable for non-ferrous materials.

Which Machine Should I Use With Versadrive ImpactaTaps?

Suitable machines for Versadrive ImpactaTaps
Machine Suitable? Guidance
Impact Wrench / Impact Driver Yes Suitable for through-hole tapping applications. Select the correct torque using the torque table below. If an exact match is not available, select the closest torque setting above the recommendation.
Rotary Pistol Drill Yes, smaller sizes Suitable for pistol drill use up to around M10 diameter. Larger tap diameters on rotary pistol drills can generate high levels of resistance and drill kickback. Select the correct RPM using the table below.
Compact Magnet Drill Generally no Compact magnet drills are not usually suitable for tapping as they do not usually have the correct features, such as reverse or variable speed.
Large Magnet / Pillar Drill Yes, where suitable Suitable for tapping if the machine has gear speed options, variable speed and a reversing feature.

What Material Thickness Can Versadrive ImpactaTaps Be Used On?

Sheet Metal

Up to 1/8"

Standard Plate

1/8" – 1/2"

Medium Plate

1/2" – 1"

Heavy Plate

Above 1"

All HMT taps in this category are suitable for sheet metal, standard plate and medium plate. Standard practice is for the thread depth to match the thread diameter – e.g. a 1/2" thread typically requires around 1/2" of thread depth.

For heavy plate above 1", consider heavy duty tapping options such as 308015 long series taps.

This guide refers to through-hole tapping. For blind-hole tapping, Spiral Flute ImpactaTaps are primarily recommended, along with a Versadrive Clutched Adapter to prevent the tap breaking when it makes contact with the bottom of the hole.

Which Cutting Lubricant Should I Use for Tapping?

SpeedLube

Recommended for all general purpose tapping applications.

BioCut Paste

Recommended for overhead drilling and other applications where liquid lubricant is not suitable.

BioCut Blue

Suitable for general drilling applications. For tapping operations, use the appropriate tapping lubricant such as SpeedLube.

Which Adapters Can I Use With Versadrive ImpactaTaps?

Impact Adapters

All the tools in this category are suitable for use in impact wrenches (see torque table).

Pistol Drill / Chuck

The Versadrive hex shank fits into any standard drill chuck. 5" and 12" Versadrive extension arbors will fit into all drill chucks.

Weldon Adapters

All Versadrive taps can be adapted for use in magnet drills with the 111130 adapter. Magnet drills must have a reverse function to be suitable for tapping.

Morse Taper Adapters

All Versadrive taps can be adapted for use in Morse Taper drills with the 111045 adapters.

HMT Versadrive ImpactaTap Best Practice

Do I need a pilot hole or a center punch?

Pilot drill the exact tapping size hole for best results.

When tapping into box section, ensure the tip of the tooling does not contact the far side of the box section at the same time.

What is the correct feed pressure?

Apply firm, steady feed pressure throughout the cut. Excess feed pressure will increase heat build-up and reduce tool life.

How many holes can I expect the tap to last?

There are many customer reports of HMT tooling lasting for hundreds of holes. However, due to the demanding nature of some portable drilling applications, this can vary widely depending on the application.

HMT can take the MATLAS details of your application and provide an estimate of tool life.

How can I prevent chipping or breakage?

Standard ImpactaTaps are recommended for through-hole applications only. For blind-hole tapping, use Spiral Flute ImpactaTaps with a Versadrive Clutched Adapter.

Tap the hole in one pass where possible, applying adequate lubrication before you start.

If the tap is over-run from the hole once it is tapped, remove the tap from the adapter and locate it in the thread by hand before reversing, to remove the risk of cross-threading.

Avoid lateral movement or tilting, which can cause damage to the tooling. Do not use excessive feed pressure – steady feed pressure keeps the tool better controlled and held at 90° to the cut, which helps prevent snagging, chipping or kick-back. Try to maintain a consistent flow of swarf.

How can I avoid cross-threading when re-threading an existing thread?

When re-threading an existing thread, use caution to avoid cross-threading, which can lead to tap breakage or thread damage.

To avoid damage to the tap, insert and start the tap into the thread by hand before driving it through at the correct torque.

How important is alignment?

Ensure the tap is inserted squarely to the hole. Poorly aligned or off-center taps will greatly increase the risk of breakage.

Recommended Impact Torque for HMT Versadrive ImpactaTaps

Select the correct torque for impact tools using the table below. If an exact match is not available, select the closest torque setting above the recommendation. Impact torque recommendations are the minimum required; for most applications additional torque is a benefit.

Impact Tapping Torque – ft-lbs (UNC, including MAX inch sizes)
Thread Diameter 1/4" Steel 1/2" Steel 1" Steel
1/4" 105 180 295
5/16" 110 205 320
3/8" 125 220 325
1/2" 135 235 375
5/8" 145 265 425
3/4" 185 295 470
7/8" N/A 370 575
1" N/A 515 735
1-1/8" N/A N/A 820
1-1/4" N/A N/A 910
1-3/8" N/A N/A 1245
1-1/2" N/A N/A 1390
1-3/4" N/A N/A 2050

The inch table applies to UNC ImpactaTaps, including MAX inch sizes. The metric table applies to Metric Coarse ImpactaTaps. Torque recommendations for UNF and NPT ImpactaTaps are not yet published. Please contact HMT for guidance.

Metric Coarse sizes – Impact Tapping Torque (Nm)
Impact Tapping Torque – Nm (Metric Coarse)
Thread Diameter 6 mm Steel 12 mm Steel 25 mm Steel
M3 105 160 N/A
M4 120 180 N/A
M5 135 200 N/A
M6 140 240 400
M8 150 280 430
M10 170 300 480
M12 185 320 512
M14 190 340 544
M16 200 360 576
M20 315 400 640
M24 N/A 600 960
M27 N/A 740 1184
M30 N/A 800 1200
M33 N/A N/A 1400
M36 N/A N/A 1640
M39 N/A N/A 1860
M42 N/A N/A 2440

Recommended Rotary RPM for HMT Versadrive ImpactaTaps

Select the correct RPM when using rotary drive tools using the table below. The inch table applies to UNC ImpactaTaps, including MAX inch sizes; the metric table applies to Metric Coarse ImpactaTaps.

Recommended Spindle Speed – Rotary RPM (UNC, including MAX inch sizes)
Thread Diameter Structural Steel <500 MPa Structural Steel <1000 MPa Stainless Steel (INOX) Aluminum Cast Iron (Grey)
1/4" 485 405 325 1455 650
5/16" 365 310 245 1095 485
3/8" 295 245 195 870 390
1/2" 240 200 162 730 330
5/8" 185 155 125 550 243
3/4" 145 125 100 440 194
7/8" 130 115 92 410 180
1" 120 100 85 370 165
1-1/8" 96 78 59 303 128
1-1/4" 90 75 55 300 120
1-3/8" 78 63 48 246 104
1-1/2" 50 41 31 158 67
1-3/4" 40 32 24 126 53
Metric Coarse sizes – Rotary RPM
Recommended Spindle Speed – Rotary RPM (Metric Coarse)
Thread Diameter Structural Steel <500 MPa Structural Steel <1000 MPa Stainless Steel (INOX) Aluminum Cast Iron (Grey)
M3 960 809 650 2700 1295
M4 730 610 490 2060 975
M5 585 485 385 1750 780
M6 485 405 325 1455 650
M8 365 310 245 1095 485
M10 295 245 195 870 390
M12 240 200 162 730 330
M14 210 175 140 625 275
M16 185 155 125 550 243
M20 145 125 100 440 194
M24 120 100 85 370 165
M27 105 90 75 330 145
M30 95 80 60 310 130
M33 84 68 51 265 112
M36 72 58 44 228 96
M39 54 44 33 171 72
M42 40 32 24 126 53

Technical Guidance from Holemaker Technology

This technical guide has been prepared by Holemaker Technology to support correct tooling selection, setup and use in metalworking applications. Torque and RPM data from the HMT USA Catalog.

Last reviewed: October 2026

Back to top

Scroll To Top