Low Volume Injection Molding
Low volume injection moulding is the route from prototype to market without the cost of hardened production tooling. With aluminium soft tooling from 25 pieces and steel bridge tooling to about 10,000, you get real moulded parts fast, then a clear path to hardened steel if the volume scales.
Free Consultation24h
Rapid Quote
25 pcs
Start Quantity
to 5,000 shots
Soft Tool Life
to 10,000 pcs
Bridge Tool
Materials
| Grade | Properties | Typical Applications |
|---|---|---|
| ABS | Cost effective and cosmetic, the common choice for low volume housings and enclosures where paint or texture is wanted. | Housings, brackets, enclosures, consumer goods |
| PP | Light, chemical resistant and cheap, good for containers, liners and living hinge parts at low volume. | Containers, liners, hinges, industrial bins |
| PC | Transparent and impact resistant, used where the low volume part must be clear or dropped. | Covers, lenses, transparent windows |
| PA66 | Engineering grade for load carrying low volume parts such as gears and brackets, natural or glass filled. | Gears, brackets, connectors, mechanical parts |
| ABS PC Blend | Tough and heat resistant for low volume enclosures that are dropped or warm, covered in detail on our ABS PC blend page. | Equipment housings, bezels, structural shells |
| TPE and TPU Overmould Options | Soft touch elastomer over a rigid substrate for grips and seals, available as insert or two-shot on compatible low volume programs. | Grips, seals, bumpers, cable strain reliefs |
Process Parameters
| Parameter | Standard Range |
|---|---|
| Aluminium Soft Tooling Lead Time | 2 to 3 weeks |
| Soft Tool Life (Aluminium) | 500 to 5,000 shots depending on geometry and filler |
| Steel Bridge Tool Lead Time | 3 to 4 weeks |
| Melt Temperature Window | 200 to 300 degree C by resin |
| Injection Pressure | 500 to 1,400 bar depending on flow length and wall |
| Recommended Wall Thickness | 1.5 to 3.0 mm, optimised for function without hard tooling |
| Mould Shrinkage | 0.4 to 2.5 percent by grade, modelled at design |
| Clamp Force Requirement | 2 to 5 tonnes per square centimetre of projected area |
| Cycle Time | 15 to 70 seconds per part depending on wall and size |
| Part Tolerance | plus or minus 0.05 mm standard, tighter by agreement |
Surface Finishes
As-moulded and Texture
Quick functional surfaces straight from the tool, the default for low volume industrial and internal parts where appearance is secondary.
SPI Polish
Cosmetic gloss surfaces on a polished cavity for low volume premium parts that must look finished.
Painting
Colour match and ultraviolet resistant coating applied after moulding, giving consistent brand colour on small batches.
Pad and Laser Marking
Logos, part numbers and serials marked permanently, used for traceability on low volume production.
In-mould Label (IML)
A pre-printed film becomes part of the surface in one shot, useful for low volume branded packaging and bodies.
Soft Touch Coating
A clear coat improving grip and mar resistance on handled low volume parts such as tool grips.
Design for Manufacturing (DFM)
- Choose aluminium soft tooling for runs under about 5,000 pieces, because hardened steel only pays back above that volume
- Optimise wall thickness to validate function without hard tooling, since a soft tool is the cheapest place to learn
- Combine low volume moulding with CNC machining for hybrid builds where one feature is too tight for the soft tool
- Plan a clear path to hardened steel if volume scales up, so the design does not have to change when the tool does
- Place gates and vents for the soft tool life, because aluminium wears and the early shots should prove the process
- Apply 1 to 2 degree draft, more on textured surfaces, for clean ejection from a softer cavity
- Model shrinkage at design using the actual grade, because the range from PP to filled PA66 is wide
- Keep the production material intent in mind, since the soft tool part should match the production part in function
- Consider multi-material and overmould where the low volume product needs a grip or seal
- Upload STEP, IGES or DXF and receive a free DFM review within 24 hours covering tool route, wall and gate
Tooling & Capacity
| Type | Lead Time | Suitable For |
|---|---|---|
| Aluminium Soft Tool | 2 to 3 weeks | 25 to 5,000 pieces, pilot runs, market testing and design validation |
| Steel Bridge Tool | 3 to 4 weeks | 5,000 to 10,000 pieces where the volume does not yet justify hardened production steel |
| Production Steel Tool | 4 to 6 weeks | 10,000 plus pieces, gloss cavities, filled grades and long run cosmetic parts |
| Multi-Cavity Tool | 5 to 7 weeks | Higher volume runs where cycle time dominates and balanced fill is required |
Quality Assurance
- The resin grade is checked on incoming material against the supplier certificate, with the lot number recorded
- First article inspection with dimensional report before the balance of the run is released
- Wall thickness and shot weight are monitored per cavity to catch short shots and flash early
- Visual inspection for sink, warp, splay and burn on every setup change
- Colour measured and recorded against the reference with delta E reported per lot where painted
- Fit checked by assembly of a sample where the part mates with others
- Melt temperature is checked at the nozzle, since a machine setting is not the true material temperature
- Low-volume resin lot traceability is retained per run, with the supplier certificate filed against it
- Every low-volume lot ships with a dimensional report, material certificate and Certificate of Origin
- SGS, Bureau Veritas or TUV third-party inspection is arranged on request for low-volume moulded parts
Applications
- Startups and seed-stage product launches
- Bridge quantities between prototype and mass production run
- Niche and aftermarket parts
- Spare and service parts
- Customised low-run product variants
- Pre-launch market testing and field trials
- Low volume enclosures and housings
- Laboratory and diagnostic equipment pilots
- Industrial small batch components
Why Choose FHY Precision
Real moulded parts from 25 pieces in aluminium soft tooling, so you validate fit and function before any hardened steel cost
A clear, planned path from soft tool to bridge tool to production steel, so scaling volume does not mean redesigning the part
All common resins moulded in house: ABS, PP, PC, PA66 and blends, matched to the production material intent
Free DFM review within 24 hours covering the tool route, wall, gate and shrinkage for your actual volume
Hybrid builds combining moulding with CNC where one feature is too tight for the soft tool
Painting, printing and marking quoted with the moulding so the finished part is one purchase order
Resin lot traceability is kept for every run, with SGS, Bureau Veritas or TUV third-party inspection available on request
Low runs produced in China at factory-direct pricing with no trading layer involved
FAQ
1. What is your minimum order quantity for low volume molding?
We start at 25 pieces using aluminium soft tooling, with a standard moulding MOQ of 100 pieces. Soft tooling is the fastest and cheapest way to get real moulded parts in hand for fit and market testing before committing to steel.
2. Should I use aluminium or steel tooling?
Use aluminium soft tooling below about 5,000 pieces and steel bridge tooling from 5,000 to 10,000. Hardened production steel only pays back above roughly 10,000 pieces per year, so for pilot and niche runs aluminium is the better economy and the faster lead time.
3. How long does aluminium soft tooling last?
Typically 500 to 5,000 shots depending on geometry and whether the resin is filled, because glass and talc abrade a soft cavity faster. For a pilot or a spare parts run that is usually plenty, and we tell you the expected life before you order so there are no surprises mid-program.
4. When should I move to hardened steel?
When annual volume passes roughly 10,000 pieces, when the cavity must be gloss or plated, or when the resin is glass filled and would wear aluminium quickly. The part design does not change, only the tool, so the move is planned from the start rather than forced by a failure.
5. Which materials can you mould at low volume?
ABS, PP, PC, PA66 and their blends, matched to your production material intent so the soft tool part behaves like the production part. Flame retardant and filled grades are fine in steel bridge or production tooling; in aluminium we advise on filler abrasion first.
6. How much does low volume tooling cost?
Aluminium soft tooling is a fraction of hardened steel because the material and machining are cheaper and the lead time is shorter. We quote the tool and the piece price together so you see the total cost to first parts, and we do not charge hardened tooling cost for a pilot that may not scale.
7. How fast can I get moulded samples?
Aluminium soft tooling takes 2 to 3 weeks, then trial moulding and first article approval add about a week. So functional moulded samples are typically in your hands in three to four weeks, faster than waiting for production steel for a program that may change.
8. What tolerances can I hold at low volume?
Plus or minus 0.05 mm standard on critical features, tighter by agreement, the same as production because the machine and the grade decide tolerance more than the tool hardness. We mark critical dimensions at DFM review and verify them on the first article.
9. Is low volume molding cheaper than 3D printing?
For a few pieces printing wins, but above roughly 25 to 100 pieces moulding gives real material properties, better surface and lower per-piece cost, and parts that match production. Printing is best for the very first concept; moulding is better for the part you will actually ship.
10. Is low volume molding cheaper than CNC machining?
For a complex shape with many features, moulding is usually cheaper per piece than machining a solid block, and it avoids material waste. For one or two very simple blocks, machining can win. We compare both against your geometry and volume and recommend the cheaper route.
11. Can you combine molding with CNC in one build?
Yes. Where one feature is too tight or too hard for the soft tool, we mould the body and CNC the critical feature, giving a hybrid part that validates the design without waiting for steel. This is common on low volume mechanical parts with a precision bore or face.
12. What surface finish can I get at low volume?
As-moulded texture is the default, with SPI polish, painting, pad or laser marking and in-mould labelling all available. For a premium low volume product we paint in brand colour for lot to lot consistency, since the soft tool itself need not be gloss.
13. Can you prototype before a low volume run?
The aluminium soft tool is itself the prototype route: 25 to 1,000 functional moulded parts in 2 to 3 weeks. Ahead of tooling we can supply machined or printed prototypes for very early form check, and we recommend a moulded prototype where snap fit and wall matter.
14. Can you supply spare and service parts?
Yes, low volume molding is ideal for spare and service parts that are needed in small batches over time. We keep the tool and the resin record so a repeat order matches the original, and we supply material certificate and Certificate of Origin with each lot.
15. How do I scale from low volume to mass production?
We design the part for the production material and tolerance from the start, so scaling means building the steel tool, not re-engineering the part. We hand the qualified design and the first article data to the production tool, and the cavity count is matched to your forecast.
16. Do you arrange third-party inspection for low volume parts?
Yes. We arrange SGS, Bureau Veritas or TUV at any stage you specify, including incoming resin verification, dimensional checks and coating verification. For regulated or branded low volume programs this is often what your customer needs, so we build the inspection point into the order.