https://youtu.be/_KrP3djoLN8?si=uXl0YFOiDOt9nrBq The stroke length on all my models is long, right around 5mm. I engineer these machines for stroke characteristics, not stroke length though. What that means is that my machines while they have a long stroke will likely not tattoo the same as another machine that has a similar stroke length. And you will always have more stroke than you need.

https://youtu.be/yfXUytl6Tqg?si=RGF666meg4rKhQy7 In this video I attempt to explain tattoo machine torque. There is some good fundamental information here, while there is so much more that could be elaborated on or addressed this is a great step in to a very complex concept.