When choosing a Spark tattoo machine stroke length, consider both the size of the tattoo and its placement on the body. The size and placement of a tattoo will dictate the type of needle being used and the length of the needle stroke. Very small tattoos, such as script or feathery designs, require delicate needles and short strokes for precision. Large, highly detailed tattoos such as portraits and realism require longer strokes with a heavier, more robust needle. Talk to the artist and make sure that the machine he or she is using offers the correct stroke length for your desired tattoo.

stroke Of 4.0+mm

The 4.0mm+ stroke is typically only used for lining, as it packs in ink with hard-hitting strokes. It can push large needle groups into the skin with ease and allows you to hang the needle farther out of the tip, which provides greater accuracy when you’re lining. However, the way it runs makes it a bad choice for shading, which requires multiple passes. Longer strokes make it nearly impossible to get smooth blends, and the multiple passes shading requires will overwork the skin and possibly leave scarring.

A medium stroke (3.5mm)

The 3.5mm is best for packing color and blending. A medium stroke has enough power for lining with smaller needle groupings, but it will struggle with larger ones. You can also do some black and grey (but not ultra-smooth portraits that require several passes).

A shorter stroke (1.8-2.5mm)

The 1.8mm to 2.5mm stroke is good for applying soft black and grey. This style often requires multiple passes to build up layers of ink. The softer-hitting stroke allows you to create these layered, smooth blends without chewing out the skin. A short-stroke cannot be used for lining. It won’t have the power to push the lines properly, and if you set the needle too deep it will not fully retract into the tube each cycle. This prevents the needle from being replenished with the tube tip’s ink, which makes getting solid lines in a single pass almost impossible. Additionally, lining requires the needle to hang farther out of the tube (for improved accuracy), which you can’t do with a short stroke. This leads to ink pooling on the skin and covering up the stencil.