Record the exact supply you changed, label two comparable samples, and make one purchase decision from the result. A useful tattoo practice log connects the mark on synthetic skin to the cartridge, material and equipment that produced it. It helps you decide whether to keep a familiar configuration, repeat a comparison or try a different supply.
Start with a question your samples can answer
“Which cartridge do I prefer for this small curved outline?” is a workable question. “Which setup is best?” is too broad for a pair of samples. Choose a short drawing you already know and reserve adjacent areas on the same practice sheet. Keep the drawing size and intended line treatment alike so that you can compare the same part of the task.
If you are building the exercise itself, begin with our seven-session fine-line practice plan. This log serves a different purpose: it records a change in supplies within an exercise, rather than planning the sequence of sessions.
Write the full cartridge identity
For a line comparison, Thunder Pro RL is a focused choice for outlines and detail. Record the complete Style, not just “liner.” For example, comparing 0803RL with 0805RL keeps the 08 diameter code and RL arrangement while changing the point count. Both are current Thunder Pro options; this is a useful comparison when the question is how a different grouping suits the same drawing.
Changing from 0803RL to 1005RL changes more than one specification. You can still try that configuration, but your note should describe it as a setup comparison rather than attributing the result to point count alone. If cartridge codes are unfamiliar, use the current product’s diameter and Style selection before preparing the samples.
Thunder Pro cartridges use 304 stainless steel and EO sterilisation, meeting ATTO’s top professional quality standard. Choose the configuration for the mark you want; professional construction supports the choice without making different groupings interchangeable. The box of 10 or 20 changes your stock quantity, so keep pack size in the buying record separately from the needle Style.
Keep a short record beside each sample
Give the sheet a session ID and each sample a letter. Record the date, exercise, machine model and settings actually used, full cartridge Style, ink product identity and practice-skin product. Add the material lot or supplied identifier when available. Use the same sample letters in your photographs; this is more useful than trying to recognise an unlabelled line several days later.
For this kind of small paired study, the 3 mm blank tattoo practice skin provides an open surface for a drawing and its labels. Its current options are 1, 3 and 5 pieces. Choose one for an initial comparison, or several when you already have repeated sessions planned; the quantity does not change the exercise.
Make the observation specific
Compare starts, turns, joins and the intended line width. “Sample B was easier to follow through the tight curve” tells you more than “B is better.” Record where a line widened, where a join became crowded, or whether the result repeated on a second attempt. A paired study helps you notice a difference; it does not isolate every effect of hand movement, settings and materials.
If ink is the variable, keep the cartridge and drawing familiar, identify both ink products, and note any preparation that differed. ATTO tattoo ink is for practice only: use it on training surfaces. Keep this log focused on those practice marks rather than predicting a healed tattoo result.
Turn the note into your next order
Keep the familiar Style when it serves the drawing consistently. Repeat a promising alternative before increasing its stock, then choose a pack that reflects how often you expect to use it. A box of 10 is a practical way to introduce a less familiar Thunder Pro configuration; a box of 20 suits a configuration already used regularly. Your log supplies the reason for that purchase.
Finish with one next step: repeat the curve, keep the current Style, or add the alternative to your regular practice. If your question has shifted from line work to shading, begin a separate exercise with the appropriate needle arrangement instead of expanding this comparison indefinitely.