- type
- concept
- created
- Tue Apr 07 2026 02:00:00 GMT+0200 (Central European Summer Time)
- updated
- Tue Apr 07 2026 02:00:00 GMT+0200 (Central European Summer Time)
- sources
- raw/notes/varsovia-meeting
- tags
- paper-industry side-trims jumbo-rolls byproduct distribution mills
Side-Trims and Jumbo Rolls
What They Are
Jumbo Rolls
Jumbo rolls are the primary output of a paper mill. These are large-diameter rolls of paper at full machine width, produced to spec for contracted buyers. They represent the mill's core revenue stream and are typically sold into specific regional markets through established distribution channels.
Side-Trims
Side-trims are the narrow strips cut from the edges of jumbo rolls during the slitting process to bring the paper to the customer's specified width. They are byproducts -- not defective, just not the target width. Side-trims are cut into smaller reels and represent sellable surplus.
The Market Separation Problem
The key insight from the Varsovia meeting: a mill that sells jumbo rolls in South America deliberately ships its side-trims to the Philippines. This is intentional market separation -- the mill does not want its byproduct competing with (or undercutting) its primary product in the same geographic market.
This behavior is universal in the industry. Mills care more about geographic visibility control than about price. If a side-trim lot ends up in the same market as the mill's jumbo rolls, it creates channel conflict: the mill's own surplus undercuts the price of its own contracted sales.
Implications for B2BPaper
Dual Visibility Settings
The platform needs two separate visibility controls per mill:
- Production lot visibility -- which countries/regions can see primary production surplus
- Side-trim visibility -- which countries/regions can see side-trim inventory (often completely different markets)
These are not just different default settings; they may be configured per item. See wiki/concepts/dual-visibility-settings for the full design.
Trader Opacity Risk
A real example from the meeting: a Chinese trader buys from a mill, tells the mill the paper is going to Morocco, but actually ships to Venezuela. The mill unknowingly competes with its own clients in another market. B2BPaper's visibility controls must be enforced at the platform level, not left to trader honesty.
Container Filling with Mixed Widths
Side-trims come in various widths. When a container is not full, the mill may fill it with nearby widths (e.g., buyer needs 165mm, mill adds 155mm + 175mm side-trims to complete the container). Whether a buyer can accept a particular width depends on their machine specifications. This connects to the container fill optimization system built in Phase 6.
How the MVP Handles This
Phase 4 (Geographic Visibility) implemented the visibility rule system:
VisibilityRulemodel with allow/deny rule types- Scope hierarchy: region -> country -> city
- Rules can be mill-wide defaults or per-surplus-item overrides
- Price adjustments per visibility rule
- Matching algorithm respects visibility filters
The dual visibility concept (separate settings for production lots vs. side-trims) was identified in the meeting but may require refinement beyond the MVP's single rule model.
Sources
- raw/notes/varsovia-meeting -- meeting where this behavior was discussed in detail
Related
- wiki/concepts/dual-visibility-settings -- the platform feature addressing this behavior
- wiki/summaries/varsovia-meeting-summary -- full meeting summary
- wiki/concepts/make-to-order-marketplace -- how surplus (including side-trims) is the entry hook
- wiki/concepts/spec-based-matching -- buyer machine specs determine acceptable widths
- wiki/summaries/checklist-summary -- Phase 4 visibility implementation