Practical research · 9 September 2026
A Rock Tumbler Batch Log You Can Actually Reuse
When a batch finishes well, the most valuable accessory is a record of what you did. A reusable log captures decisions and observations, not merely days. Use your machine's instructions for loading and operation; this worksheet records the process rather than prescribing one universal recipe.
Give the batch an identity
Label the batch and record its machine, barrel and material source. Photograph the dry starting material with the label visible. If you are unsure of a rock's identity, write 'unknown' rather than assigning hardness from color. Separate uncertain material for evaluation instead of assuming a mixed bag behaves uniformly.
Record both loaded weight and barrel fullness using the definitions and limits in the manufacturer's manual. Lortone publishes model-specific instructions for its machines. A volume that looks right does not prove the motor's load limit is respected.
Source: Lortone: model instructions
Record what enters and leaves
At every cleanout, note the stage, abrasive product and amount, water setup, media and actual runtime. Record rocks removed because of cracks, pits or an acceptable finished shape. If you refill with approved media, document that too. The load after coarse grinding can differ substantially from the starting batch.
Do not treat a rotary-barrel log as a recipe for a vibratory bowl. Motion, loading and water requirements differ. Use the correct instructions and treat this shared worksheet only as a place to record your own procedure.
Use a stage decision sheet
Inspect representative pieces dry under consistent light. Wetting can hide scratches, so a wet-stone photograph is a poor substitute for a dry observation. Write the defect you are trying to remove before deciding to continue or advance.
| Stage record | Useful detail |
|---|---|
| Input | Rock group, weight, media and abrasive |
| Run | Start/stop times and interruptions |
| Observation | Pits, fractures, scratches or haze |
| Decision | Repeat, advance, separate or stop |
| Evidence | Dry photo filenames and retained sample |
Learn from a disappointing batch
Suppose stones were smooth before polish but emerged with isolated scratches. Notes can help distinguish possible contamination from a defect already present at the prior stage. A missing picture or unrecorded media change identifies an uncertainty; do not fill it with a confident explanation.
For the next comparable batch, change one suspect variable at a time within the maker's instructions. Keep tools and supplies organized by stage so finer work does not receive coarse residue. Do not wash abrasive slurry into household drains.
Save a short repeat recipe
After success, summarize the material, machine, method and inspection decisions on one page. Keep the detailed log behind it. The repeat recipe should say what the surface looked like when you advanced, not only how many days elapsed.
Natural material varies, so the record is a starting point for inspection rather than a guaranteed timetable. Add a note when a later batch behaves differently. Over time, the useful result is a small set of material-specific records you can actually explain and repeat.