BATCH-CAPACITY WORKSHEET
Define every number before comparing capacity
Copy the wording from each exact-model manual. Do not convert a barrel rating into a stones-only allowance unless the manufacturer does. If the basis, one-barrel operation, or placement rule is missing, mark it unknown and ask the manufacturer before ordering or operating the machine.
Shortlist record
Exact machine and revision: ____________________________________
Manual or manufacturer page: __________________________________
Barrel count and identity: _____________________________________
Manufacturer’s capacity wording: ______________________________
What that number includes: □ complete loaded barrel □ stones only □ other □ unknown
Two-barrel rules: □ combined limit recorded □ per-barrel limit recorded □ placement recorded □ one-barrel operation confirmed □ unknown
Planned load A / stage / owner: _________________________________
Planned load B / stage / owner: _________________________________
Exact wear parts located: □ barrel □ lid/seal □ belt □ other __________ □ unknown
Decision: □ single fits □ double solves a named need □ evidence incomplete
| Reference model | Documented format | Load-definition boundary | Parts and care evidence |
|---|---|---|---|
| KomeStone K1Open model sourceOpen parts or instructions | One 2.5 lb-class barrel | Not defined on the current product page; confirm in the supplied exact-model manual. | K1 motor fits K1 only. K1/K1 Pro belts are listed as not fitting K2 or K4. |
| KomeStone K4 familyOpen model sourceOpen parts or instructions | The saved catalog title describes two barrels; an exact current model page was not located. | Total capacity, per-barrel allowance, and rock-only versus complete-load basis remain unresolved. | K4 replacement belts are separately listed as incompatible with other models. |
| Lortone 3AOpen model sourceOpen parts or instructions | One 3 lb-capacity rubber barrel | The product page states barrel capacity but does not define a safe stones-only allowance. | The maker flags required oiling and publishes a dedicated 3A instruction link. |
| Lortone 33BOpen model sourceOpen parts or instructions | Two 3 lb rubber barrels | Twin barrel ratings are not permission to treat six pounds as stones-only weight. | The maker flags required oiling and publishes instructions specifically covering 33B. |
No worksheet entries are stored by this site. Use the exact supplied manual for loading, placement, oiling, and service.
Begin with the reason for separation
RockTumbler.com’s A-R2 description identifies several practical uses for two barrels, including separate materials and different stages. We turn that into a buying question: what would you put in each barrel on the first day? If one answer is only “something eventually,” the extra capacity may not be your most useful starting expense.
A double setup works best when each load has a name, owner, and written stage. Label the barrel or associated container in a way that does not interfere with moving parts or sealing surfaces. Keep the record clear enough that another household member could identify the correct batch without opening it.
Capacity numbers need a definition
A pound rating may describe a loaded barrel rather than the amount of bare rough you can add. Check the exact manufacturer instructions and weigh the load as directed. Do not add the two headline barrel capacities and assume that figure is a safe weight of stones alone.
Current manufacturer pages illustrate why the noun after the number matters. Lortone describes the 3A as a single 3 lb-capacity barrel and the 33B as twin 3 lb barrels; neither product-page statement should be silently rewritten as a stones-only allowance. KomeStone calls K1 a 2.5 lb-class barrel, while a current exact K4 model page or manual was not located during this source review. Treat K4 capacity as unresolved rather than importing a related page's wording.
Also check whether running one barrel alone is allowed, how barrels must be positioned, and whether controls are shared. A shared base does not necessarily mean independent timing or speed. If independent control is the reason you are buying, verify it explicitly before checkout.
Use this three-scenario comparison
Imagine the workflow after the purchase rather than comparing only the product photographs. These scenarios are an editorial planning aid; they are not performance claims for any named machine.
- One occasional project: a single barrel keeps records and cleanup straightforward; wait until you have an appropriate load.
- Two people with separate stones: two barrels can preserve ownership, provided an adult operator or designated hobbyist manages the machine correctly.
- An ongoing batch queue: two barrels can separate work, but each needs appropriate contents, consumables, and a plan for inspection.
- Mixed rocks with uncertain compatibility: extra barrels do not resolve identification. Sort and research the materials first.
Count the handling burden
Make room for two wet batches at changeover, not just two barrels on the base. You may need separate trays and clearly labeled containers to avoid mixing materials or stages. Check that you can lift, open, clean, and reseal each barrel comfortably. A shared machine should simplify your routine rather than make the workspace feel crowded.
Replacement support is another comparison point. KomeStone currently lists a K1-only motor, K1/K1 Pro belts that do not fit K2 or K4, and separate K4 belts described as incompatible with other models. Lortone directs both 3A and 33B owners to model-specific instructions and flags oiling on each product page. These are useful ownership signals, not permission to transfer a part or service step to a visually similar machine.
If you remain undecided, write a batch schedule using your actual available rough. Choose the arrangement that leaves the fewest unexplained gaps: an empty second barrel, an oversized load, or a cleanup session you cannot accommodate. This is more informative than selecting the larger machine because it looks more advanced.
Questions at the workbench
Can two barrels run different tumbling stages?
They can keep stages physically separate when the machine and each load are operated according to their instructions. Track each barrel clearly and check whether the machine’s controls are shared.
Does two-barrel mean twice as many finished stones each month?
Not necessarily. Usable rough, correct loading, stage repeats, cleanup, and your schedule affect throughput. Two containers alone do not establish a finished-output rate.
Can I run only one barrel on a double barrel tumbler?
Check the exact model’s manual for permitted loading and barrel placement. Do not infer this from the appearance of the base.
Sources & further reading
- RockTumbler.com: Thumler’s A-R2 workflow options
- RockTumbler.com: A-R2 replacement components
- KomeStone: K1 model page
- KomeStone: exact-model parts catalog
- KomeStone: K4-specific replacement belts
- Lortone: 3A rotary tumbler
- Lortone: 33B rotary tumbler
- Lortone: tumbler instructions and manuals
Machine instructions take precedence for its loading, materials, operation, and maintenance. Send a correction.
