Tumbling brass casings is a popular method for cleaning, polishing, and deburring spent brass, preparing it for reloading. But how long should you actually tumble your brass? The answer isn't a simple number; it depends on several factors. This comprehensive guide will delve into the variables that influence tumbling time and help you achieve that perfect, gleaming finish every time.
Factors Affecting Brass Tumbling Time
Several key factors determine the optimal tumbling time for your brass:
1. Initial Condition of the Brass
- Lightly Soiled Brass: If your brass is only mildly dirty, with minimal fouling or damage, you might only need a relatively short tumbling time, perhaps 30 minutes to 2 hours.
- Heavily Soiled Brass: Brass heavily soiled from range use, with significant fouling, corrosion, or damage will require significantly longer tumbling times, potentially 4-8 hours or even longer. Extremely dirty brass might benefit from a pre-cleaning step before tumbling.
- Type of Brass: Different brass alloys might respond differently to tumbling. Some might require slightly longer or shorter times depending on their hardness and composition.
2. Tumbling Media Used
- Corn Cob Media: This is a popular choice known for its relatively gentle cleaning action. It generally requires a longer tumbling time, often 4-6 hours, to achieve the desired results.
- Walnut Media: Walnut media is a bit more aggressive and often requires a shorter tumbling time, typically 2-4 hours, but may still need longer for heavily soiled brass.
- Plastic Media: Plastic media is often used in conjunction with other media types, and tumbling time will depend on the overall mix and the brass condition.
- Steel Media: Steel pins are typically used for deburring and can significantly reduce tumbling time compared to other methods. However, you need to carefully monitor your brass to prevent damage.
3. Tumbling Compound Used
- Brass Cleaning Compound: Different compounds offer varying levels of cleaning power. A stronger compound may allow for shorter tumbling times, while milder compounds might require more extended periods.
- Lubricant: Adding a lubricant can significantly reduce wear on your tumbling media and brass, potentially impacting the overall time. Check the manufacturer's instructions for your specific lubricant and tumbling media.
4. Tumbler Type and Capacity
- Rotary Tumbler: These tumblers often require longer tumbling times due to the gentler action.
- Vibratory Tumbler: These are generally faster and more aggressive, often requiring shorter tumbling times.
- Tumbler Capacity: Overfilling the tumbler can significantly reduce its effectiveness and increase the required tumbling time.
Determining the Right Tumbling Time: A Practical Approach
The best way to determine the ideal tumbling time for your specific setup is through experimentation.
- Start with a Short Tumbling Time: Begin with the lower end of the suggested time ranges mentioned above, based on your brass condition and media used.
- Check Your Brass Frequently: Remove a small sample of your brass at intervals (e.g., every hour) to assess the cleaning progress.
- Observe and Adjust: Continue tumbling until you achieve the desired level of cleanliness and finish.
Beyond Time: Other Considerations
Remember, achieving the perfect finish isn't just about the time you tumble; it’s about the process. Proper media-to-brass ratio, sufficient lubricant, and the right type of compound all contribute to the final result. Don't just focus solely on the clock; pay close attention to your brass.
Conclusion
There's no magic number for how long you should tumble brass. Experimentation is key to finding the optimal time for your specific needs and equipment. By understanding the factors influencing tumbling time and employing a systematic approach, you can achieve consistently clean, polished, and deburred brass, perfectly prepared for your reloading projects. Remember to prioritize safety and always follow the manufacturer’s recommendations for your specific tumbling equipment and compounds.
