Cutting Internal Threads - Instructions

 

If you want to cut a thread, it's not as difficult as you might think with the right tool. Here we show you in a short instruction how you can quickly and easily make an internal thread yourself.

 

Manual thread cutting with tap iron and tap. Set of 3 taps, tap iron
Internal thread tap and tap wrench

The following tools are required for tapping internal threads:

 

 

TIPP! Um ein Gewinde von Hand zu schneiden, verwendet man am besten einen dreiteiligen Gewindescheider Satz. Als erstes wird mit dem ersten Gewindeschneider das gewünschte Gewinde vorgeschnitten, danach folgt der zweite Gewindeschneider und anschließend wird mit dem dritten Gewindeschneider das Finale Gewinde geschnitten.

 

In the first step you need the suitable hole or core hole for the desired internal thread. In our core hole table you will find all drill diameters matching the thread size. The thread is then cut into this core hole in several steps.

 

Which drill you need for which internal thread, you can see here in the thread cutting table:

 

Cutting Internal Threads Chart

Thread

Sizes

Drill Hole

(mm)

Metric

Pitch (mm)

M1 0,75 0,25
M1,1 0,85 0,25
M1,2 0,95 0,25
M1,4 1,1 0,30
M1,6 1,3 0,35
M1,8 1,5 0,35
M2 1,6 0,40
M2,2 1,8 0,45
M2,5 2,1 0,45
M3 2,5 0,50
M3,5 2,9 0,60
M4 3,3 0,70
M5 4,2 0,80
M6 5,0 1,00
M7 6,0 1,00
M8 6,8 1,25
M9 7,8 1,25
M10 8,5 1,50
M12 10,2 1,75
M14 12 2,00
M16 14 2,00
M18 15,5 2,50
M20 17,5 2,50
M22 19,5 2,50
M24 21 3,00
M27 24 3,00
M30 26,5 3,50
M36 32 4,00
M42 37,5 4,50
M48 43 5,00
M56 50,5 5,50
M64 58 6,00

* All information without guarantee.

Cutting Internal Threads - step by step instructions

 

1. Punch the spot before drilling.


2. Select the correct drill bit for the appropriate thread and drill the hole.


3. Slightly countersink the hole with a taper countersink.


4. Apply a tropical cutting oil to the tap and to the drill hole.


5. Then turn the first tap one turn clockwise.

    Attention! The tap must always be perpendicular to the workpiece!


6. Then turn the tap a half turn counterclockwise.

    This is very important in order to break off the chip that occurs during cutting.


7. Repeat the cutting process as described in points 5 and 6 until the desired depth has been reached.

    Then repeat points 4 to 6 with the second and third taps.

 

 

The function of the finished thread can then be checked with a suitable screw.

 

 

If you want to know how to cut an external thread yourself in just a few steps, you will find all the information here.