Tuesday , February 20 2018
Home > Lathe Projects > A DIY Powered Benchtop Tapping Machine

A DIY Powered Benchtop Tapping Machine

Howdy Guy’s and Gal’s!

It’s my turn now to contribute to the site with a tool that I consider a “must-have” for the home shop machinist. A powered benchtop threading/tapping machine!

For some 25 years I have used this simple tapping machine in my workshop. One of my old colleagues invented it more than 40 years ago and he gave it to me when he retired.

I know he never serviced the machine, and haven’t needed to service it either, so it’s definitely proven to be a durable design.

The function is simple push / pull action, you can see short video her on YouTube:

The drive mechanism is a rubber wheel pushed over the driveshaft on the electric motor.

Once you get the motor spinning in the correct direction (it always seems to start the wrong way the first time … thank’s Murphy) you just push the workpiece against the tap, and the rotation starts. The harder you push the higher torque. I have made M2 – M8 threads primarily in sheet metal.

I have made some different guide-plates to fit different tap sizes and workpiece shapes.

I also made some photos, sorry I did not clean this “old Lady” before her photo session.


Simple Tapping Machine by SD Denmark

The electric motor used her is 3 phase 1400 rpm, I think this gives the perfect cutting speed.

Simple Tapping Machine by SD Denmark

hmmm what can I say… seen from top..

Simple Tapping machine by SD Denmark

I have mounted the tapping machine on old iron table to give it some weight to prevent it from moving around when in use. But I also like having the option to store it when not in use. (I couldn’t find any space on my workbench ;-) )


[auction-affiliate tool=”lister”]


Download the Tapping Machine Plans:

Plans for this small device are available in following formats.

Plans in PDF format (dimensions in mm, and 2nd dim’s is imperial, sorry for the awkward imperial dim’s, it’s designed in mm)

[download id=”76″]

STEP file

[download id=”74″]


[download id=”75″]

SolidWorks files on request – send me (stranix) a private message via the forum system.

If you have any feedback I’d love to hear it!

– Brian Madsen (aka stranix)


[adrotate group="4"]

About stranix

Check Also

Shop Tip: A Fixture for Drilling Holes in Round Stock

Here's a handy weekend metalworking project for you! James Instone shows us how he made a fixture that's useful for drilling accurate holes in round stock. Jim's fixture is simple, functional, and includes interchangeable drill guides.


  1. Very nice! The use of a friction drive is quite appropriate in this scenario.


    I’ve used a ready made “push pull” tapper for a while now. Mine is made by Supreme. Its slightly more convenient than this machine because it can be used at arbitrary angles. However, I do envy your friction drive.

  2. harborfreight8x12

    Wow.  I am truly impressed.  Thanks for sharing.  If ever one needed a mass production set-up this would be it.

    Regards, Al

  3. Hi Brian,

     very impressive. Could you indicate the power of the motor (Watt). 

    than’s Daniel

  4. That is one slick design!

  5. your pdf file will not open in adobeCryCry 

  6. stranix,

    Could you please send me the SolidWorks files.