Plastic (acrylic) polishing often involves a multi-step process to remove machine marks, get a smooth finish and then brighten the part. The part on the left is a machined part with turning lines and a matte surface finish.
The polished part on the right required a 3-step vibratory tumbling process. Each step used a Hardwood Tumbling Media with a different dry tumbling cream. These results can also be successfully achieved in barrel tumblers.
Step 1 utilized a moderately abrasive cream (Shynolyte Pre-Polishing Cream).
Step 2 used Pegs treated (Microlyte Polishing Cream) for polishing to a very smooth, unifrom finish.
Step 3 was needed to achieve the shiny finish and used a low-abrasive cream (Hi-Glos Final Cream).
Each step was 12-16 hours to give the process enough time to accomplish the specific task. For rough-cut parts, Hardwood Media treated with a cutting compound such as Dry Abrasive Cream will provide edge rounding and remove heavy machine marks and scratches.