Thread guide

With self-tapping, there is a chance that the tap will not enter at an angle of 90 degrees. To avoid a "curve" of the thread, you can make a special conductor, which will direct the threaded tool strictly perpendicular to the surface.

For crafts, you will need a thick washer and several nuts with common thread to make the device universal. The nuts are welded in a circle so that the thread remains untouched. Then through the nut you need to drill a hole in the washer.

To use the resulting tool, you need to drill a hole in the metal and use a clamp to press the washer with the desired thread on top, then screw the tap into the nut, which will enter the workpiece strictly at an angle of 90 degrees.