PMU Tips(36)--What is stroke and Why is stroke length so important

1. What is stroke?

Inside a PMU machine, the internal mechanism moves up and down at a very high speed.
Each time it moves, it drives the push bar inside the needle cartridge, which in turn pushes the needle in and out of the skin to implant pigment.

However, one very important difference between machines is how long this up-and-down movement is.
And this difference in length will have a huge impact on your final work.

Inside every PMU/tattoo machine, there is a part called a cam.
This is a small rotating disc that converts the motor’s circular motion into the needle’s linear up-and-down motion – in other words, the actual movement path of the needle when it implants pigment.

The cam determines the distance the needle travels in and out with each cycle.
This distance is called the stroke length.

2. Why is stroke length so important?

If the stroke length is short, the needle hitting the skin will feel softer and gentler.

If the stroke length is long, the needle hitting the skin will feel harder and more punchy, with stronger impact.