Production By-Products: Should Your App Record More Than the Main Finished Item?
If a production run leaves material your team deliberately keeps, specify that output separately from the main finished item. Give it an identity, a measured or otherwise agreed quantity, and a destination. Do not let a production-complete button imply that only the main product exists, or that every leftover is ready to use.
This guide helps scope a small production or inventory application. It does not classify waste legally, establish material safety, or allocate production costs for your accounts.
When an extra output deserves a record
Ask what happens after the production step. Is material kept for another job, sold separately, awaiting assessment or sent for disposal? An undifferentiated note saying “offcuts” cannot explain the quantity the team expects to find later.
Odoo's by-products documentation describes residual materials produced alongside a finished product. It lets a bill of materials identify those by-products and their quantities, and optionally the operation where they arise. This supports a concrete example of multiple outputs, not a promise that your existing system records them correctly.
Use the feature only where the record answers a real operational question. If nobody needs a quantity, location or subsequent use, adding a new stock item may create maintenance work without a clear benefit. Conversely, material used by another job should not appear from nowhere in that job's consumption record.
A planned output is not the observation
An expected by-product quantity belongs in the plan. The actual amount recovered belongs to the completed run. Decide how the team enters or confirms the latter and how differences are explained.
In a hypothetical cutting workshop, reusable offcuts may vary between runs. The application should follow your agreed recording rule rather than silently treating the recipe's expected amount as a measurement. This is a proposed requirement, not a behaviour established by the cited Odoo page.
Record the unit as well. “A container” may be a handling description rather than a dependable quantity of material. Agree whether the operation counts pieces, measures weight, or uses another justified basis. Do not invent conversions between them.
Storage is different from permission to reuse
Odoo documents product movements showing a by-product moving from the virtual production location to its storage location. For your app, ask staff to identify the real destination and any required pending-assessment status.
A material can be physically present while not approved for reuse. Have a competent person define suitability, inspection and handling rules where those matter. The software record should reflect those decisions, not create a safety claim from a product name.
If assessment later rejects the material, use the agreed disposal workflow rather than deleting the output so it appears never to have existed. If it is accepted for another job, retain the link between the originating run and subsequent movement at the traceability level you actually require.
Corrections should explain the changed balance
Odoo says it registers by-product quantities when a manufacturing order is marked done. Your implementation still needs a deliberate correction process. What if someone confirms the main output but forgets a secondary one? What if a container was weighed incorrectly?
Ask for a correction linked to the original run, with the reason and any downstream consequences visible. A later correction must not casually rewrite material already recorded as consumed elsewhere. The exact stock and financial treatment requires review by the people responsible for those systems.
Demonstrate one run from plan to next use
For your production-app acceptance criteria, use fictional materials and require:
- A planned secondary output and a separately confirmed actual quantity.
- Clear units and a named storage destination.
- The agreed handling of a run producing none of the expected secondary material.
- Pending assessment without automatic availability for reuse, where your process requires it.
- A subsequent approved movement linked to its originating output.
- A rejected output following the disposal path without disappearing from history.
- A mistaken quantity corrected with an explainable remaining balance.
Bring that sequence to a business-application scoping discussion. The feature earns its place when staff can explain where the material came from and what may happen next.
Three boundary questions
Is a by-product always usable stock?
No such conclusion follows from creating a record. Use eligibility must come from your reviewed process, including any necessary specialist assessment.
Does recording it determine its value?
No. This guide defines quantities and movements, not cost allocation, valuation or tax treatment.
Is this the same as scrapping damaged stock?
No. A production-output record explains material arising from a run. A scrap event explains the agreed removal of identified goods from usable stock. A particular output may later enter that separate process.