Low Volume Vacuum Casting: 10 to 500 Parts Without Mold Costs
Produce 10 to 500 production-grade parts without expensive injection molds. Multi-mold parallel casting delivers bridge production in 7 to 35 days at a fraction of tooling cost. ISO 9001 certified quality at FIRMFG.
Low Volume Vacuum Casting: Bridge Production Without Mold Costs
Low volume vacuum casting is the most economical manufacturing solution for orders of 10 to 500 parts. It bridges the gap between prototyping and injection molding by using silicone molds and liquid polyurethane resin to produce parts that match production-grade material properties — without the $5,000 to $50,000 tooling investment of injection molding.
At FIRMFG, we run multiple silicone molds in parallel to scale vacuum casting up to 500 parts per order. Each mold yields 20 to 30 copies, so a 500-part run uses 15 to 20 molds cast simultaneously, completing in about 35 days. Per-part cost drops sharply as volume increases, reaching a floor near $42 per part at 100 units — the sweet spot where vacuum casting beats every alternative.
This page breaks down quantity guidelines, per-part cost at every volume, lead times, materials, and quality standards so you can decide whether low volume vacuum casting is the right fit for your project. Ready for pricing? request a quote and receive a detailed price and lead time within 24 hours.
Low Volume Vacuum Casting Specifications
Key capabilities and production parameters for low volume vacuum casting at FIRMFG.
| Specification | Value |
|---|---|
| Batch Size Range | 10 – 500 parts per order |
| Per-Mold Yield | 20 – 30 copies per silicone mold |
| Multi-Mold Parallel Capacity | Up to 500 parts via parallel molds |
| Lead Time | 7 – 35 days (volume-dependent) |
| Dimensional Tolerance | ±0.1 mm (±0.004") |
| Material Options | 20+ polyurethane resin grades |
Low Volume Vacuum Casting vs Injection Molding
For 10 to 500 parts, vacuum casting almost always wins on cost and lead time. Here is how the two processes compare across the criteria that matter most.
| Criteria | Low Volume Vacuum Casting | Injection Molding |
|---|---|---|
| Tooling Cost | $150 – $500 per mold | $5,000 – $50,000+ per mold |
| Lead Time (First Parts) | 7 – 10 days | 4 – 8 weeks |
| Per-Part Cost (100 pcs) | $20 – $60 | $2 – $10 |
| Material Match | 90% production match (PU resins) | 100% production material |
| Design Flexibility | High — change design between batches | Low — mold changes costly |
| Max Economical Volume | 500 parts | 10,000+ parts |
Vacuum casting wins on tooling cost and lead time for any volume under 500 parts. Injection molding only becomes cheaper once amortized tooling cost drops below the vacuum casting per-part floor — typically around 1,000 parts.
Choose Vacuum Casting When
You need 10 to 500 parts, can accept 90% material match, and want first parts in 7 to 10 days. Best for bridge production, market testing, and pre-production validation.
Choose Injection Molding When
You need 1,000+ parts, require exact production material, and can wait 4 to 8 weeks for steel tooling. Best for full-scale production where unit cost is the priority.
Crossover Point
The cost curves cross near 500 to 1,000 parts. Below 500, vacuum casting is cheaper; above 1,000, injection molding wins. Between 500 and 1,000, request a crossover analysis to decide.
Quantity Guidelines: Matching Volume to Mold Strategy
The number of silicone molds we run — and whether we run them sequentially or in parallel — is the single biggest driver of lead time and per-part cost. Here is how we scale production across the 10 to 500 part range.
1 – 10 Parts
- Mold Strategy
- 1 mold (single)
- Lead Time
- 7 – 10 days
Mold cost dominates; per-part cost is highest. Ideal for functional prototypes and design validation.
10 – 100 Parts
- Mold Strategy
- 2 – 4 molds (sequential)
- Lead Time
- 10 – 18 days
Mold cost amortized across more parts; per-part cost drops sharply. Best for pilot runs and market testing.
100 – 300 Parts
- Mold Strategy
- 4 – 10 molds (parallel)
- Lead Time
- 18 – 28 days
Parallel molds compress lead time; per-part cost approaches the floor for vacuum casting.
300 – 500 Parts
- Mold Strategy
- 10 – 20 molds (parallel)
- Lead Time
- 28 – 35 days
Maximum economical volume for VC. Beyond 500 parts, injection molding becomes the lower-cost option.
Cost Per Part Analysis: Mold Amortization Curve
Per-part cost falls steeply from 1 to 20 units as the one-time mold cost is amortized, then floors near $42 where variable casting cost dominates. The table below uses a representative 100 x 60 x 40 mm ABS-like part with basic finishing.
| Order Volume | Mold Cost | Total Cost | Per-Part Cost | Notes |
|---|---|---|---|---|
| 1 unit | $300 (1 mold) | $330 | $330 | Mold + first cast |
| 5 units | $300 (1 mold) | $450 | $90 | Mold amortized over 5 parts |
| 10 units | $300 (1 mold) | $600 | $60 | Single mold, mid-life |
| 20 units | $300 (1 mold) | $900 | $45 | Full mold life reached |
| 50 units | $600 (2 molds) | $2,100 | $42 | Second mold added |
| 100 units | $1,200 (4 molds) | $4,200 | $42 | Sweet spot for VC |
| 200 units | $2,400 (8 molds) | $8,400 | $42 | Parallel molds in production |
| 500 units | $6,000 (20 molds) | $21,000 | $42 | Maximum efficiency |
Example based on a 100 x 60 x 40 mm ABS-like part with matte finish. Actual quotes vary with geometry, material, and finishing requirements. Mold cost assumes $300 per mold at 25 copies per mold.
Cost Optimization Tips
- Order in quantities that use full mold life (multiples of 20 to 25) to avoid paying for partially-used molds.
- Standardize on one material across the batch to avoid separate mold setups and resin changeovers.
- Consolidate multiple part numbers into a family mold when geometry allows, sharing mold setup cost.
- Specify finish requirements up front so we optimize the master pattern rather than reworking cast parts.
- For 300+ parts, ask us to run a crossover analysis against injection molding to confirm vacuum casting is still the lower-cost option.
- Plan parallel mold production early — more molds add upfront cost but cut calendar time significantly.
Lead Times by Order Volume
Lead time scales with quantity because more parts require more parallel molds. Running molds in parallel keeps the 500-part lead time under 35 days.
| Order Quantity | Lead Time | Molds Used | Notes |
|---|---|---|---|
| 10 parts | 7 days | 1 mold | Single mold, sequential casting |
| 50 parts | 12 days | 2 molds | Two molds, parallel casting |
| 100 parts | 18 days | 3 – 4 molds | Parallel molds overlap |
| 200 parts | 25 days | 6 – 8 molds | Multi-mold production run |
| 500 parts | 35 days | 15 – 20 molds | Full parallel capacity |
Factors That Affect Lead Time
Part Complexity
Complex geometry with undercuts or fine details adds 1 – 3 days for mold prep and slower demolding.
Material Selection
Specialty resins (transparent, high-temp) require longer cure and post-cure cycles, adding 1 – 3 days.
Finishing Requirements
Painting, texturing, pad printing, or assembly adds 2 – 5 days depending on complexity.
Mold Count
More parallel molds reduce calendar time but require additional master patterns upfront.
Materials Available for Low Volume Production
Material selection drives cost, lead time, and how many parts a mold can yield. The right strategy matches resin to part function while keeping the production run economical.
| Material | Best For | Recommended Volume | Cost | Lead Time Impact |
|---|---|---|---|---|
| ABS-like PU | Housings & enclosures | 10 – 500 | $ | Standard (no add) |
| PC-like (Transparent) | Lenses & clear covers | 10 – 200 | $$ | +1 – 2 days (post-cure) |
| TPU-like (Flexible) | Grips, seals, overmolds | 10 – 300 | $$ | +1 day |
| Silicone Casting | Heat-resistant & gaskets | 10 – 200 | $$$ | +2 days |
| PP-like / Nylon-like | Living hinges, clips | 10 – 300 | $$ | +1 day |
| High-Temp PU | Under-hood, thermal | 10 – 200 | $$$ | +2 – 3 days |
ABS-like
Default for housings and enclosures. Lowest cost, standard lead time, full 500-part capacity.
PC-like (Transparent)
For lenses and clear covers. Requires pressure casting and post-cure, adding 1 to 2 days.
TPU-like (Flexible)
For grips, seals, and overmolds. Shore 20A to 90A range, adds about 1 day to lead time.
Silicone
For heat-resistant parts and gaskets. Highest material cost, adds about 2 days to lead time.
Quality Standards for Low Volume Batches
Low volume does not mean low quality. Every batch of 10 to 500 parts is produced and inspected under the same ISO 9001:2015 system that governs our full-scale manufacturing.
Dimensional Consistency
CMM inspection on critical dimensions across every batch, ensuring ±0.1mm repeatability part to part.
First Article Inspection
FAI report provided with the first part of each batch, verifying all called-out dimensions and features.
Sampling Inspection (AQL)
AQL 2.5 sampling plan applied to production batches, with full inspection on critical features.
Material Certification
Material datasheets and certificates of conformance supplied with every order, traceable to resin lot.
Batch Traceability
Each part labeled with mold ID, shot number, and resin lot for full traceability through production.
ISO 9001 Quality System
All vacuum casting production runs under our ISO 9001:2015 certified quality management system.
Low Volume Vacuum Casting FAQ
Answers to the most common questions about ordering 10 to 500 parts by vacuum casting at FIRMFG.
QWhat is the maximum batch size for low volume vacuum casting?
The practical maximum for low volume vacuum casting is 500 parts per order. Beyond 500, the cumulative cost of multiple silicone molds (each yielding 20 to 30 copies) makes injection molding more economical. For 500 parts we run 15 to 20 molds in parallel, completing the order in about 35 days. For higher volumes, we recommend transitioning to injection molding tooling.
QWhat is the per-part cost at 100 units?
At 100 units, the per-part cost for a typical ABS-like part (100 x 60 x 40 mm) is approximately $40 to $45, including amortized mold cost, casting, and basic finishing. This is the sweet spot for vacuum casting, where mold setup costs are spread across enough parts to approach the per-part floor. The exact price depends on part size, material selection, and finishing requirements.
QWhat is the lead time for 500 parts?
A 500-part order typically takes 35 days from CAD approval to shipment. This includes master pattern creation (2 to 3 days), producing 15 to 20 silicone molds in parallel (5 to 7 days), and casting all parts across the molds (20 to 25 days). Rush production can compress this to 28 days with priority scheduling and additional parallel molds.
QHow consistent are parts across multiple molds?
Parts cast from different molds maintain ±0.1mm dimensional consistency because every mold is pulled from the same master pattern. We verify the first article from each mold against the FAI report to catch any deviation early. Silicone mold wear is monitored shot by shot, and molds are retired before dimensional drift occurs. Minor cosmetic variation between molds is possible but stays within agreed AQL tolerances.
QHow is quality controlled for low volume batches?
Every low volume order includes first article inspection (FAI), AQL 2.5 sampling inspection on the production batch, and CMM measurement of critical dimensions. Material certificates and resin lot traceability are provided with shipment. All processes run under our ISO 9001:2015 certified quality management system, with batch records retained for full traceability.
QHow much does a silicone mold cost?
A single silicone mold for vacuum casting costs $150 to $500, depending on part size and complexity. Each mold yields 20 to 30 parts, so the mold cost amortized across a 100-part order is only $2 to $5 per part. This is roughly 1/100th the cost of an injection mold ($5,000 to $50,000), which is why vacuum casting is far cheaper for volumes under 500 parts.
Applications for Low Volume Vacuum Casting
Low volume vacuum casting serves any scenario that needs more than a handful of parts but less than full production — where speed, finish, and material fidelity matter more than the lowest possible unit cost.
New Product Launch
Produce 100 to 500 market-ready units before injection mold tooling is ready, hitting launch dates without delay.
Market Testing
Run 50 to 200 units through user testing and pilot markets to validate demand before committing to hard tooling.
Spare & Replacement Parts
Reproduce obsolete or low-demand service parts without maintaining expensive legacy injection molds.
Trade Show Samples
Deliver 20 to 100 production-finish demo units that look and feel identical to the final manufactured product.
Bridge Production
Fill the gap between prototyping and full-scale injection molding, supplying inventory while molds are being cut.
Pre-Production Validation
Build 100 to 300 units for regulatory testing, field trials, and design verification under real-world conditions.
Related Vacuum Casting Services
Explore our other vacuum casting capabilities tailored to different volume ranges and use cases.
Vacuum Casting Service
Complete vacuum casting hub — 20+ materials, ±0.1mm tolerance, 5-day prototype turnaround, ISO 9001 quality.
Learn MoreSmall Batch Vacuum Casting
Small batch production for 10 to 100 parts with fast turnaround and cost-effective single-mold runs.
Learn MoreVacuum Casting Prototyping
Rapid prototyping with vacuum casting for 1 to 20 parts, ideal for design iteration and functional testing.
Learn MoreStart Your Low Volume Vacuum Casting Project
Upload your CAD files and get a free low volume vacuum casting quote within 24 hours. Our engineers recommend the optimal mold strategy, material, and quantity to minimize per-part cost. ISO 9001 certified quality, tolerances to ±0.1mm, and 7 to 35 day turnaround for 10 to 500 parts.