Custom Injection Molding & Custom Plastic Injection Molding Manufacturer

You send the drawing. Our engineers run the DFM, cut the tool, and mold the parts under one roof in Dongguan — and the person who signs off on your DFM is a mold engineer who has spent 20+ years correcting these problems on the bench, not a sales rep relaying

Here is what that buys you on a custom injection molding project:

Your DFM is reviewed by a mold engineer with 20+ years on the bench
40+ injection machines, 90–400T, robotic arms running 24/7
In-house mold shop and injection floor — tool and parts never leave the building
Free preliminary DFM at quote; Moldflow & CMM reports on order
No MOQ and no mid-project price hikes — one transparent number

What Is Custom Injection Molding — and the 4 Challenges We Solve

Custom injection molding builds a dedicated steel or aluminum tool to your geometry, then injects molten polymer to produce identical parts at volume. The process itself is well understood. The risk lives in four places, and a quote that stays quiet about all four is the one that surprises you later. Here is where parts actually fail, and how we close each gap at the

High Upfront Tooling Cost & Trial Cycles

Tooling is the real commitment on any program — a multi-week build plus tryout before the first good part exists. The cost that hurts is not the steel; it is reworking the tool after a tryout reveals a problem the design review should have

FixWe send a preliminary DFM at the quote stage, before you commit a dollar to tooling. Wall thickness, draft, and gating get corrected on screen, where a change costs an email instead of bench

Shrinkage, Warpage & Flash

Polymer shrinks as it cools. Miss on gate location, cooling layout, or pack pressure and you get sink marks, warp, or flash along the parting

FixFor complex geometry we run Moldflow to predict fill, weld lines, and warpage before steel is cut. Our operators with 10+ years on the bench adjust the injection temperature, speed, and pressure during mold trial; for geometry-driven warpage we add a cooling fixture to set the part

Glass-Filled & Engineering Resins

Resins filled with 30–60% glass fiber abrade screws and barrels and short-fill when the process drifts. The higher the fiber load, the faster that wear builds, and an unmanaged screw starts dropping fill before anyone catches

FixPart of our fleet runs screws in wear-resistant material built for abrasive filled resins, so we tool and run these grades as routine work. Screw and barrel wear sits on a scheduled inspection cycle, with worn components replaced before fill quality

Mold Transfer & Setup Downtime

Moving a tool between factories forces re-qualification, and dimensions drift during the

FixWe build the mold and molding the parts in the same factory — no transfer, no recalibration gap, no finger-pointing between vendors. Gating, cooling, and process parameters stay with the team that cut the tool, so production never re-learns the part from

Knowing the failure modes is one thing; the services built to prevent them are

Our Custom Injection Molding Services

KTM runs an in-house mold shop and an injection floor as one operation, so your tool and your parts stay in one vendor. That removes the transfer step where most projects lose dimensional control. Our custom injection molding services cover four scopes:

Mold manufacturing

designed and cut on Fanuc CNC machining centers, with cavity surfaces finished on a Sodick mirror EDM. Export the tool for your own presses, or leave it with us to run.

Injection molding production

your tool kept in-house and molded to your release schedule, with full lot traceability on every shot.

Metal insert & nut overmolding

we machine the hardware ourselves, so insert-to-cavity fit is controlled in-house instead of bought in. That tighter match holds position and pull-out spec.

Secondary operations

pad printing, assembly, and finishing, so parts leave the floor ready to

Because one team owns both the tool and the molding process, a dimensional issue gets traced to its real cause — gate, cooling, or process — instead of bouncing between vendors. That is why customers treat KTM as a molding partner rather than a job

Capability only matters once you see the parts it

Custom Injection Molded Parts We Make

If a part can be molded after DFM, we have likely cut a tool for something close. Our custom injection molded parts span small precision components to panels near 1.5m. Organized by part type:

Type	Examples
Enclosures & housings	POS-terminal housings, power-outlet covers, electronics enclosures
Precision functional parts	safety latches, press-fit clips, connectors, threaded-insert components
Machinery & equipment housings	lawn-mower housings, sailboat plastic parts, agricultural and milking-equipment housings
Large structural parts	door panels, equipment covers, lamp housings, aerospace and medical-device housings near 1.5m

Precision part holds because of how the floor is built:

Clean-grade Fanuc high-speed machines hold tight, repeatable shots
Temperature-controlled workshop, held 24 hours, keeps dimensions stable run to run
Critical features verified on a CMM, not assumed

These custom molded plastic parts already ship into automotive, electronics, and medical programs, so as your custom plastic parts manufacturer we confirm moldability before tooling, not after.

Send us your part — we'll tell you if it's moldable, and how.

A part is only as good as the resin behind it, and resin choice is where an engineering grade separates a working part from a warped

Plastic Materials We Mold

You send a resin spec; we tell you how it behaves in the cavity before steel is cut. KTM molds across four resin families, and the material drives gate location, cooling layout, and screw selection on every

Family	Resins	Typical parts we've molded
Commodity	ABS, PP, PE, PS	enclosures, fruit crates, household tubs
Engineering	PC, PA6/66(+GF), POM, PET, PBT	gears, bearings, electrical housings
High-performance	PEEK, PPS, PEI (Ultem), IXEF	under-hood parts, aerospace components, camera parts
Elastomers	TPU, TPE, LSR	grips, seals, baby-bottle rings

Custom ABS injection molding and custom PP injection molding cover most consumer work. For load-bearing parts, custom nylon injection molding and custom POM injection molding hold tight dimensions, since both resins resist creep and run with predictable shrink once dried

Glass-filled grades are where bench experience shows. We have molded many camera housings in 50%-GF IXEF — a stiff resin that wears hardware fast and breaks down into short shots if moisture stays in the pellet. We dry every hygroscopic resin to its spec window before it runs, then hold barrel temperature per grade so the fiber carries strength into the part instead of degrading in the

Surface finish follows the same logic. We cut molds to VDI/MT texture standards when you need a defined matte or grained face, and we map shrink per resin so the texture reads evenly across the part.

Pick the wrong resin for a wall section and you fight warpage for the life of the tool. That call is exactly what our engineers make for free before you commit to tooling, which is why the next step costs you nothing.

You bring the drawing. Before you spend a dollar on tooling, our engineers run the DFM and flag wall, gate, and material risks — no cost, no commitment, no obligation to order.

Industries We Serve

Resins, tolerances, and paperwork change by industry. KTM molds across regulated and commercial sectors, and three of them have their own engineering deep-dives.

Automotive

water tanks, mirror housings, light-strip covers, and ventilation parts that take heat and pressure under the hood. (See our automotive injection molding page.)

Aerospace

seat-lock buckles, armrests, and door-frame housings molded in high-performance resins for cabin-grade requirements. (See our aerospace injection molding page.)

Medical

surgical-instrument components, syringe parts, and device enclosures molded to hygiene and biocompatibility standards. (See our medical injection molding page.)

Beyond those three, we mold for:

Consumer electronics

keyboards, terminal housings, and insert-molded assemblies that seal chips and wiring inside the plastic

Industrial

irrigation fittings, pipe components, tool cases, and stackable totes

Appliances & home

dryer housings, fans, planters, and personal-care bottles and caps

Infant & toys

molded toys, bottles, nipples, and sealing rings

Each sector taught us a failure mode, and those lessons feed the DFM you

What ties these programs together is volume: most customers reached us at one quantity and scaled to another with the same tooling and the same team. Here is how that ramp works without a

From Prototype to Mass Production

A part rarely stays at one volume. You validate a design, then ramp. KTM covers the full curve in-house, so you don't re-source and re-qualify a supplier every time demand shifts. There is no MOQ on any of the four paths

Prototype injection molding

early parts off aluminum or soft tooling to confirm fit and function before you commit to hardened steel. Fewer surprises later. (See our prototype injection molding page.)

Rapid injection molding

quick-turn tooling when the schedule, not the budget, drives the project. We compress mold build to get first shots in your hands sooner. (See our rapid injection molding page.)

Low-volume injection molding

bridge runs and small batches where hard tooling isn't justified yet. You get molded-grade material and finish without full-production tooling cost. (See our low-volume injection molding page.)

Production injection molding

full-volume runs on our 40+ presses, all fitted with robotic arms for unattended 24/7 output and repeatable cycle times. For large structural parts, our partner network extends to 3300-ton clamp force, so a 1.5m+ automotive or aerospace housing isn't a limit. (See our large part injection molding

The advantage is continuity. The DFM, the tooling, and the inspection method that proved your prototype carry straight into production. One supplier owns the data the whole way, which removes the requalification gap that breaks most ramp

Continuity only matters if the quality system behind it holds up under audit. That's what the next section

Why Choose KTM as Your Custom Injection Molding Manufacturer

Most custom injection molding companies tell you the parts are good. We hand you the paper trail to prove it. Every program moves through a five-stage documentation chain you can audit at any point:

Stage	Deliverable	When you get it
1	Preliminary DFM	At quotation, before any tooling spend
2	Detailed DFM report	After order, full feature-by-feature review
3	Moldflow analysis	For complex geometry, thin walls, or glass-filled resin
4	T1 trial report	First-shot results with recorded process parameters, pictures and videos
5	CMM report + material certificate	Before mass-production sign-off

That chain is backed by a traceable inspection system. Dimensions are verified on a CMM, optical comparator, hardness tester, and hand metrology — calipers, micrometers, height gauges, pin gauges, and go/no-go gauges — so every lot ties back to a measured record rather than a verbal

The equipment behind those numbers is imported and named, not vague:

Tooling

Fanuc CNC machining centers and a Sodick mirror-finish EDM for cavity and core work

Molding

Fanuc and Haitian presses with robotic part removal

Inspection

CMM, optical projector, and full hand-gauge sets for closed-loop QC

Two points decide most supplier reviews, and both sit with the engineer and the buyer who can say no. First, pricing is transparent — tooling, unit price, and secondary operations are itemized before you commit, with no mid-project price hikes after the mold is cut. Second, the relationship lasts: several current clients have run with us for 15, 10, and 6 years, supported by an ISO 9001 quality system and engineers who join your video calls in fluent English. Our project team works to 8 p.m. local time to overlap North American and European hours, so a technical question rarely waits a full

Audited documentation, named equipment, and traceable QC are what turn a sample approval into a multi-year supply program. The next question is usually simpler: what will it cost?

Get every cost on the table before you commit — tooling, unit price, and secondary operations itemized in one quote. No hidden fees. No price hike after the mold is already cut. Attach your drawing or 3D file and an engineer prices it directly, not a sales desk.

Custom Injection Molding Cost

Custom injection molding cost is driven mostly by the mold, not the parts. Tooling carries the upfront investment, while per-piece price drops sharply as volume climbs. Across typical programs, mold cost ranges from roughly $2,000 USD for a simple single-cavity soft tool to $80,000+ USD for large, multi-cavity, or hot-runner production

Geography moves the number significantly. Industry benchmarks put a single-cavity tool at around 2,500 in China versus about 14,000 from a U.S. shop, with unit price following the same gap. That spread is why most of our clients run development and production here while keeping their own engineering control

The variables that set your final figure:

Part size, wall thickness, and geometry complexity
Cavity count and gating type (hot runner vs. cold runner)
Resin grade and abrasiveness (glass-filled grades shorten mold life)
Required tight tolerances and surface finish

For a full breakdown of tooling tiers, amortization, and where the savings come from, see our dedicated guide on custom injection molding cost. The questions below cover what engineers ask before they send the first

Frequently Asked Questions

Still have a part-specific question? Send the drawing and an engineer will answer it

Talk to our project engineer and get professional

Send your drawing and an engineer will review it. You'll get a preliminary DFM, a transparent price, and a straight answer on whether the part is moldable as