Custom Tooling · Single & Multi-Cavity
Custom Plastic Injection Mold --
Single & Multi-Cavity
This category covers custom tooling built from steel to your part drawing, with cavity count determined by your annual volume requirements and dimensional tolerances -- not by a standard catalog.
We issue a DFM report before quoting steel, so you know what engineering decisions are being made and why before any money changes hands.
The same mold supports first-article validation through production runs, with documented ownership, spare parts, and maintenance terms from the start.
§ 02 -- Part Types
Parts We Have Cut Steel For
For the same part, we typically present two to three cavity-count options, placing mold cost, unit cost, and capacity constraints side by side in one table so you can make the comparison directly.
The entries below reflect part families we have tooled and shipped. If your part fits one of these descriptions, the engineering questions you will face are the ones we have already solved.
Consumer electronics housings and internal brackets
Class-A cosmetic surfaces that must clear the sink-mark threshold without secondary painting.
Wearable device mid-frames and rear covers
Thin-wall geometry with tight flatness requirements across a small footprint.
Smart home and camera housings
Outdoor UV resistance and waterproof rib geometry that must not compromise wall-thickness uniformity.
Router and set-top box enclosures
Long flow paths that require weld-line position control to avoid structural and cosmetic defects.
Robot vacuum structural parts and side-brush brackets
Wear resistance and assembly fit tolerances on moving components.
Power tool housings
Glass-fiber-reinforced resin with overmolded grip zones and screw-boss pull-out strength.
Automotive interior buttons, HVAC grilles, and exterior lamp housings
Class-A surface on the A-face with weathering-grade material qualification.
Industrial sensor and instrument housings
IP67 sealing-face flatness and gasket groove dimensional consistency.
Connector housings and wire-harness overmolds
Micro-feature detail with cavity-to-cavity consistency across 16+ cavities.
Medical consumables and diagnostic device components
Cleanroom assembly compatibility and material traceability documentation.
§ 03 -- Technical Parameters
Mold Specification Reference
§ 04 -- DFM Problem Resolution
Three Problems We Resolve Before Cutting Steel
These are the most common failure modes on multi-cavity tooling projects. Each one is addressed in the DFM phase, documented in writing, and signed by the engineer responsible for your mold.
Dimensional Drift Across Cavities
Symptom
Parts from different cavities measure within spec individually but fall outside assembly tolerance when paired.
Root Cause
Unbalanced gate and runner geometry causes unequal fill and pack pressure across cavities, producing systematic dimensional offsets.
DFM Resolution
We run mold-flow simulation to calculate per-cavity fill differential and pressure loss. Where the differential exceeds the tolerance budget, we propose a gate or runner geometry change before any steel is committed. The conclusion, simulation screenshots, and proposed modification are written into the DFM report.
Sink Marks and Weld Lines on Cosmetic Surfaces
Symptom
Visible depressions or flow-line marks appear on Class-A surfaces after T1 sampling, requiring rework or secondary finishing.
Root Cause
Non-uniform wall thickness and gate position cause material flow fronts to converge, producing packing deficits and visible weld lines.
DFM Resolution
Risk locations are marked directly on the part drawing. We present three options -- local wall reduction, rib geometry modification, or gate relocation -- with the cost and lead-time implication of each. The selected approach is documented before steel is ordered.
Warpage and Ejection Marks on Deep Thin-Wall Parts
Symptom
Parts bow after ejection or show white stress marks at ejector pin locations, failing flatness or cosmetic requirements.
Root Cause
Non-uniform cooling and ejector pin placement on thin sections create differential shrinkage and localized stress concentrations.
DFM Resolution
We propose cooling channel routing and ejector layout before cutting, and we state explicitly which corner radii and draft angles cannot be reduced below the specified values and the structural reason for each constraint. These are not verbal recommendations -- they are written into the DFM report with dimensional callouts.
If any of the above is not addressed in writing in our quotation, you should not issue us a purchase order.
§ 05 -- Cooperation Models
Two Ways to Work With This Category
§ 06 -- Deliverables
What You Receive at Delivery
Every item below is included as a standard deliverable. None of these are available as optional add-ons -- they are part of the project scope from the start.
Engineer-signed DFM report
Identifies draft angle issues, sink-mark risk, gate position, parting line proposal, and wall thickness map. Signed by the named engineer responsible for your mold.
Mold-flow analysis report
Simulation results covering fill sequence, pressure distribution, weld-line location, and cooling uniformity, with screenshots and conclusions referenced against your drawing.
Mold assembly drawing, component drawings, and BOM
Full documentation package for your records and for use by any injection shop or maintenance facility that handles the mold.
T1 full-dimensional CMM report
In English, with GD&T callouts, measured value versus drawing tolerance for every critical dimension, produced on Zeiss coordinate measuring equipment.
CMM raw data file
The original measurement data in a format importable into your own inspection system for independent verification. Not a PDF summary only.
Trial-shot video with mold number and timestamp
Continuous video of the T1 sampling run, labeled with the mold reference number and date, for your production records.
Steel and hot-runner material certificates
Mill certificates for mold steel and brand documentation for hot-runner components, confirming the grades stated in the quotation were used.
Wear-part and spare-part list
Itemized list of consumable and wear components with standard part numbers so you can source replacements independently.
Weekly project progress reports
Sent every Friday during the build phase, with timestamped workshop photographs and video showing actual steel at each machining stage.
The mold is not scheduled for shipment until the customer has reviewed and provided written confirmation of the CMM report. No exceptions.
§ 07 -- Who This Category Is For
This Category Fits These Situations
You need a first custom mold and want the tooling supplier to carry the engineering judgment -- not just execute a drawing -- so that DFM issues are surfaced and resolved before steel is committed.
Your annual volume falls in the 【PLACEHOLDER】 range and you need a cavity-count recommendation that balances mold investment against unit cost and machine capacity, with the comparison presented in writing.
You are benchmarking a local tooling supplier's capacity or pricing and need verifiable evidence -- CMM reports, mold-flow outputs, and steel certificates -- rather than assurances.
If your inquiry consists of a single sentence asking for a price without a 3D file or drawing attached, we will not return a quotation. A meaningful response requires geometry.
§ 08 -- Frequently Asked Questions
Questions Engineers Ask Before Issuing a PO
How many cavities do I need for my part?
Cavity count is determined by annual volume, part size, machine tonnage, and cycle time -- not by a default preference. For each project we present two to three cavity-count options and compare mold investment, per-unit cost at your projected volume, and the machine tonnage required for each configuration. You choose based on your actual production plan, not on our recommendation alone. We put all three scenarios in writing so the comparison is transparent.
Will parts from different cavities in the same mold measure consistently?
Cavity-to-cavity consistency is controlled through two mechanisms. First, mold-flow analysis is used to balance fill and pack pressure across all cavities before steel is cut -- this is the stage described in Module 4. Second, the T1 CMM report measures critical dimensions on parts from every cavity individually, so any systematic offset is identified and corrected before the mold is accepted. You receive per-cavity measurement data, not an averaged result.
Can I take delivery of the mold only and run production elsewhere?
Yes. The Tooling Only model described in Module 5 transfers full ownership and exclusive rights to you. Spare parts are specified to DME or HASCO standard dimensions so your local supplier can source them independently. Authorized third parties may collect the mold from our facility with your written authorization. We do not require you to route production through us, and we do not retain any rights to use the tooling for other purposes.
How do you substantiate the mold life figure quoted?
Mold life is a design value, not a guarantee independent of operating conditions. We quote it based on the steel grade and heat treatment specified, the expected maintenance interval, and the ejection cycle count for your part geometry. The quotation states the steel grade used for each mold component, the heat treatment specification, and the assumed maintenance frequency. Production batch traceability is maintained so that actual shot counts can be tracked against the design value over the mold's service life. We will tell you when a component is approaching its wear threshold before it causes a dimensional failure.
If I need a design change after T1, how is the cost calculated?
The quotation specifies the number of modification rounds included in the project scope. Modifications within that count are covered. Modifications beyond the included rounds are priced separately, with labor and steel costs itemized independently. A full-dimensional CMM report is issued both before and after any modification so you have a documented record of what changed and whether the revised dimensions are within tolerance. There is no lump-sum rework charge without a breakdown.
§ 09 -- Related Categories
Other Tooling Categories
Each entry below describes how that category differs from this one. If your part requirement fits one of these descriptions more closely, follow the link.
High-Cavity & Family Mold
For projects where multiple different part geometries are molded in a single tool, with cavity allocation strategy and cost tradeoffs specific to family-mold configurations.
Overmolding & 2-Shot (2K) Mold
For parts that combine rigid and soft-touch materials in a single component, requiring a second mold-close cycle or rotary platen.
Insert Molding Mold
For parts where metal inserts, threaded brass, or other pre-formed components are loaded into the mold before the shot and encapsulated in plastic.
Hot Runner Mold (YUDO / HASCO / INCOE)
For projects where hot-runner selection, gate vestige size, and color-change frequency are the primary tooling decisions.
LSR Silicone Rubber Injection Mold
For liquid silicone rubber parts, which require cold-runner tooling, different surface release treatment, and different volume economics from thermoplastic molds.
Injection Molding & Assembly Service
For customers who already have tooling and need production capacity, secondary operations, and assembly under one roof.
Die Casting Mold & Parts
For metal die-cast components -- aluminum, zinc, or magnesium -- handled under the ACAT Tech brand.