Injection Mould Tool Identification: Safe Cavity Insert and Revision Marking
Injection moulding workshops need to distinguish a complete mould tool from its cavity inserts, cores, slides and spare components. When an insert is removed for polishing, repaired, replaced or transferred between sites, a handwritten box label can become separated from the metal. Permanent identification may help, but a misplaced laser mark can damage a functional surface or create an unacceptable stress raiser. This guide explains how to decide what to identify, where to put the reference and when to use a separate tag rather than mark the tool itself.
Start with the mould-tool register, not the laser
Assign the tool assembly a stable internal ID and each removable component a subordinate reference. For example, a fictional tool IM-042 might contain IM-042-CAV-A, IM-042-CAV-B and IM-042-SLIDE-03. The engraved characters should point to a controlled record containing the drawing revision, material, heat-treatment state, inspection history and approved location. A revision is not necessarily part of the permanent identity: a repaired insert may retain its ID while its drawing changes. Define that rule before producing labels.
Separate the mould manufacturer's original identification, safety notices and traceability obligations from supplementary workshop IDs. Do not cover, remove or recreate mandatory markings. Obtain permission from the tool owner and approval from the responsible tooling engineer before modifying any component.
Classify the marking location by risk
Possible candidates for engineering review include a non-working external face on a removable tool carrier, an approved flat identification land or a separate plate fixed to a designated bracket. Do not assume that a cavity face, parting line, sealing land, ejector contact, cooling passage, sliding fit, thin section or highly stressed region is safe to mark. Even a shallow surface mark can alter a precision finish or trap contamination. A dot-peen impression adds local plastic deformation and may be inappropriate on hardened or fatigue-sensitive tooling.
Ask the engineer for an annotated drawing showing the allowed marking envelope, maximum permissible depth or surface change, finish requirement and any prohibited zones. If the drawing does not authorise direct marking, use a separate traceable tag or container ID. Do not experiment on a production cavity.
Fibre laser, dot-peen or removable identification?
| Method | Where it may help | Approval questions |
|---|---|---|
| Fibre laser on an approved metal land | Fine text on a compatible flat external area | Material response, heat effect, finish, contrast, corrosion and permitted location |
| Portable dot-peen on a suitable separate carrier | Large tool frames that cannot reach a bench | Impact loading, workholding, access, local distortion and noise |
| Engraved loose metal tag | Storage boxes, tool trolleys and dedicated holders | Secure attachment, contamination, loose-part risk and readable location |
| Temporary removable label | Short-term process tracking | Heat, coolant, solvent, adhesive residue and removal before moulding |
A laser marker's listed 110 × 110 mm field is a supplier-listed characteristic of ONAGONE's current 20W/30W product variants, not evidence that it can safely mark a particular tool steel. Likewise, the handheld ML-SC12030A's supplier-listed 120 × 30 mm area does not establish acceptable marking depth for a mould component. Require a test on representative non-critical material and a signed first-off approval.
A practical five-stage workflow for a 12-insert refurbishment batch
- Receive and reconcile: count the 12 inserts against the tool register; photograph existing identification and record discrepancies before work starts.
- Approve the position: tooling engineering identifies the permissible location on each insert drawing; any unapproved insert remains unmarked.
- Prepare artwork: create a controlled text file from the register, including a revision reference only if the register's policy requires it. Avoid ambiguous characters such as O/0 or I/1.
- Trial and inspect: test a sacrificial coupon of comparable material and finish; evaluate contrast, dimensional effects, surface condition and readability after normal cleaning. Do not infer safety from appearance alone.
- Release and record: inspect every ID against the register, record operator, date and approved process, then return components to labelled positions in the tool store.
If an insert fails the first-off test, stop and ask the tooling engineer to select a different location or a separate identification method. Repeatedly marking over an error is not an acceptable correction.
Quote the complete identification service, not seconds of laser time
Hypothetical illustration only: suppose a workshop sells 40 authorised supplementary metal tags for mould-tool storage at £18 each excluding VAT. Revenue is £720. Assume blank materials £60, four labour hours at £20 (£80), energy £6, allocated machine depreciation or finance £25, expected remakes and returns £30, and customer acquisition £45. These example direct and allocated costs total £246, leaving £474 contribution before rent, insurance, software, tax and other overheads. It is not a guaranteed gross profit or a real customer result. A VAT-registered seller charging 20% VAT would invoice £864 including £144 output VAT; that £144 is not trading income. Input VAT recovery and the correct VAT treatment depend on circumstances.
For direct tool marking, engineering review, testing, possible rejection, transport and liability can outweigh the price of a small tag. Quote those separately. Do not promise suitability, a certification or a turnaround without approved drawings and verified equipment.
Equipment to compare on ONAGONE
Compare the ONAGONE 20W/30W fibre laser configurations (£2,594.37 listed) or review the handheld dot-peen marker (£1,495.76 listed). Both product pages were publicly accessible on 1 November 2026 but displayed Sold out, despite positive quantities in Shopify Admin. Treat them as equipment research links until public checkout availability is resolved. Verify enclosure, extraction, controller, support and exact supplied accessories before committing.
Frequently asked questions
Can I laser-mark a hardened cavity insert?
Only after the tool owner and competent engineer approve the exact material, location and process. Hardness alone does not establish suitability; use a separate tag when approval is unavailable.
Should the revision number be engraved permanently?
Not automatically. The stable component ID can link to a changing revision record. Follow the owner's configuration-control policy.
Can a handheld dot-peen machine mark a mould frame?
Potentially on an approved non-critical surface, but impact marking needs engineering approval and suitable workholding. Never assume the frame is exempt from structural or precision requirements.
What is the simplest low-risk first service?
Produce separate, owner-approved tool-store plates and storage labels, prove your record accuracy and sample quality, and consider direct marking only when a qualified customer supplies a written process approval.
Next step: take a sample tag drawing, substrate specification and a list of required identifiers to the ONAGONE fibre laser product page, then request written confirmation of machine suitability and public availability. For wider preparation, read the plate workholding guide.
Safety: follow the machine's instructions, appropriate laser guarding and fume-control risk assessment. This article concerns authorised industrial traceability, not changing any vehicle identity or producing counterfeit manufacturer plates.