For QD, thorough early communication is the blueprint for success, and strict quality control is the guarantee of commitment.
The first step in cooperation: What do you need to prepare and communicate?
For smooth cooperation, the more detailed the information you provide, the more the product we can make will meet your expectations. Please prepare the following items:
Drawings and materials required
- Detailed technical drawings (2D or 3D): These are the most important documents. They should clearly indicate all dimensions, tolerances, geometric tolerances (such as flatness and roundness), draft angles (if applicable), and surface finish requirements.
- 3D digital model: A 3D model (such as .stp or .igs format) is ideal. It allows us to intuitively understand every detail of the product and perform design for manufacturability (DFM) analysis, identifying potential problems in advance.
- Material Specifications: Please specify the metal material you require. Such as 304 stainless steel, 316L stainless steel, mild steel, aluminum alloy, etc. If there are specific international or industry standards (such as ASTM, DIN), please specify them as well.
- Other special requirements: Tell us the end-use scenario and expectations of the product. Does it require polishing, sandblasting, or electroplating? Does it need to withstand high pressure? This information directly affects our process selection.
| Type of Information | Key Content | Why It’s Important? |
| 2D Engineering Drawing | All dimensions, tolerances, datums, and surface treatment requirements | The final basis for quality inspection, ensuring each dimension complies with specifications |
| 3D Digital Model | Accurate three – dimensional solid data | Used for mold design, CAM programming, and simulation analysis. Avoid interference and design defects |
| Material Standard | E.g., “ASTM A351 CF8M” (316 stainless steel) | Ensure the composition and mechanical properties of the melted metal fully meet your expectations |
| Special Requirement Description | E.g., “Need to pass a 1.5MPa hydrostatic test”, “Food – grade application” | Determine additional quality control points and post – treatment processes |
Key issues to communicate with manufacturers
When communicating with QD sales or engineers, you can ask the following questions:
“Based on my drawings, what manufacturing difficulties do you think there are? Do you have any suggestions for design optimization?” (Investigating the manufacturer’s experience and DFM capabilities)
“What materials are recommended for my product? Why?” (Listen to professional advice and balance cost and performance)
“How is the approximate mold cost and unit price calculated? What is the MOQ?” (Clearly define the cost structure)
“How long does the entire production cycle take? (Including mold making, proofing, and mass production)” (Reasonably arrange project progress)
“What quality inspection reports can you provide? (such as material report, dimension inspection report, flaw detection report)” (Confirm the quality assurance system)
Quality control: How does QD ensure that there are no mistakes in every link?
We regard quality as our life. We implement quality control throughout every production step:
1. Wax Pattern Control: No mistakes from the first step
Precision starts with the initial wax pattern. We use high-quality molds and a constant-temperature wax press to ensure consistent shrinkage. We spot-check or even fully inspect each batch of wax patterns for critical dimensions, using CMM for 100% inspection. This eliminates batch errors at the source.
2. Mold Shell Production and Sintering: A strong “shell” is crucial
Slurry application, sanding, and drying—each step is strictly regulated. Each completed layer of the mold shell is inspected to prevent defects such as sand leakage and nodules. The mold shell must be sintered at high temperature before pouring to achieve sufficient strength and air permeability.
3. Melting and pouring: The core process, precise control
This is the most critical step:
- Composition Control: A direct-reading spectrometer is used to rapidly analyze the composition of the molten steel in the furnace. This ensures that the molten steel meets material standards and will not be poured if it does not meet the standards.
- Temperature Control: An infrared thermometer is used to monitor the molten steel temperature in real time. This ensures that pouring occurs within the optimal pouring temperature range, preventing defects such as cold shuts and under-pouring.
4. Post-processing and Inspection: A Rigorous “Physical Inspection” Before Shipment
After cooling, the casting undergoes processes such as shell vibrating, cutting, and sandblasting to take shape. But this isn’t the end; even more rigorous inspections await:
Full dimensional inspection: For the first batch of finished products, we use CMM to conduct full dimensional inspection again to ensure that they are consistent with the drawings.
Surface Inspection: Each casting undergoes a detailed manual inspection to identify defects such as pores, cracks, and sand buildup.
Nondestructive Testing (NDT): Depending on your requirements and application, we can provide:
- Penetrant testing (PT): Used to detect surface-opening defects.
- Magnetic particle testing (MT): Used to detect near-surface defects in ferromagnetic materials.
- X-ray testing (RT): Used to detect internal defects such as shrinkage cavities and pores.
Only after all the above inspections have been passed, the casting will be packed and shipped with the corresponding inspection report and delivered to you.
FAQ
1. What primarily determines the cost of lost wax casting?
Main factors include mold costs and the weight and complexity of the product itself. The more complex the design and the higher the requirements, the higher the cost. We can provide design optimization advice to help you maintain performance while maintaining budget.
2. How long does it take from ordering to receiving samples?
Usually 4-6 weeks. This includes mold making, trial sample production, post-processing, and sample inspection. The specific turnaround time depends on the complexity of the product.
3. What kind of precision and surface finish can lost wax casting achieve?
Dimensional accuracy is very high. Generally, we can achieve CT4-CT7 (national standard). Surface finish can reach Ra 3.2μm or higher, and can be mirror-finished after polishing.
4. What metal materials can I choose from?
A wide range of options. These include various carbon steels, stainless steels, tool steels, aluminum alloys, copper alloys, and high-temperature alloys like cobalt- and nickel-based alloys. We have an extensive materials database and can recommend the most suitable option for you.
5. Can you provide special surface treatments?
Yes, we can. We offer a one-stop service, including sandblasting, polishing, electroplating (nickel and chrome), electrochemical polishing, painting, and other common surface treatments to meet your diverse needs.