How to calculate the price of CNC sheets? Influencing factors, quotation methods and industry cases

Introduction: Why Is There Such a Big Difference in CNC Sheet Prices?

When purchasing CNC machined sheets, are you often dazzled by a variety of quotations? For the same 3mm thick stainless steel sheet CNC machining, the quotations from different suppliers may vary by more than 30%; When purchasing in bulk, how much is the discount reasonable? In fact, the fluctuation of CNC sheet prices is not without a trace, but is determined by multiple factors such as material costs, processing technology, and industry demand. This article will help you thoroughly understand the core logic of CNC sheet prices from basic cognition to practical application, whether it is purchasing decisions or cost accounting.

1. Core Influencing Factors of CNC Sheet Price: What Details Are Determining Cost?

1.1 Dismantling {CNC Sheet Cost Composition}: Where Exactly Is the Money Being Spent?

The final quotation for CNC sheets is by no means a single material expense, but a comprehensive superposition of multiple costs. Based on practical experience in the industry, the typical cost composition is as follows (taking a 1000 yuan CNC sheet processing order as an example):

For example, a mechanical processing factory purchased 304 stainless steel plate CNC cutting, the unit price of raw materials is 28 yuan/kg, and the labor cost is 40% higher than that of ordinary cutting due to the need for laser fine cutting during processing, and the processing cost accounts for 38% of the final total cost.

1.2 {Material price fluctuations} that cannot be ignored: What factors are influencing?

Raw material prices are the foundation of CNC sheet prices, and their fluctuations are primarily influenced by three main factors:

• International commodity market: For example, the correlation between aluminum plate prices and electrolytic aluminum futures prices reached 85%, and the price of electrolytic aluminum rose by 12% in 2023, directly leading to an average increase of 8%-10% in aluminum plate CNC processing prices;
• Market supply and demand: During the peak season of the construction industry (March-May, September-November), the demand for carbon steel plates surges, and the price may be about 15% higher than in the off-season;
• Policy and logistics: Tightening environmental protection policies will increase the production costs of steel mills, while fluctuations in international logistics freight rates have a significant impact on the price of imported titanium alloy plates, up to 20%.

It is recommended that the purchaser reduce the risk of fluctuations by signing long-term supply agreements or locking in raw material prices.

1.3 {Sheet Specification vs. Thickness}: How do specification differences affect quotations?

The size and thickness of the plate directly determine the amount of material and the difficulty of processing, which is the key to price accounting:

• Thickness impact: For every 1mm increase in thickness, the processing time increases by an average of 12%-15% (taking laser cutting as an example), such as the unit price of 1mm acrylic plate cutting is about 1.2 yuan/meter, while the unit price of 5mm acrylic plate cutting is 3.8 yuan/meter;
• Size impact: Non-standard sizes (such as exceeding 1220*2440mm standard board) need to be customized, and the material loss rate will increase from the regular 5% to 15%-20%, and the price will naturally rise.

1.4 Money-saving tips: {Bulk purchase discount} vs. {shipping and regional difference}

• Bulk purchase: The industry's regular discount rules are 90% off for purchases of more than 500 pieces, 8.5% off for more than 1,000 pieces, and 80% off for more than 2,000 pieces. An electronics factory purchased CNC-machined aluminum alloy shells, and after increasing from 100 pieces/batch to 1,000 pieces/batch, the unit cost was reduced by 18%;
• Regional price difference: In the Yangtze River Delta, Pearl River Delta and other plate processing concentration areas, due to the perfect supply chain, the price is 5%-10% lower than that in inland areas; In terms of freight, the freight of plates within 1 ton is about 50-100 yuan in the same city, and the freight cost is 150-300 yuan / ton for inter-provincial transportation, and the logistics cost needs to be calculated in advance for long-distance procurement.

1.5 Understanding {Supplier Pricing Strategy}: Avoiding "Hidden Charges"

There are two main types of supplier pricing logic:

• Cost-plus pricing: 15%-25% of the total cost is increased as profit, suitable for standardized products;
• Market-oriented pricing: Popular specifications (such as 3mm stainless steel plate, 5mm aluminum plate) are priced at the average market price, while unpopular specifications are increased by more than 30%.

When purchasing, it should be noted that some suppliers will list the cost of surface treatment, precision calibration and other expenses separately, and be sure to clarify the service items included in the quotation before signing the contract.

2. Common CNC Sheet Types and Price Ranges: How to Choose the Best?

The following is the latest market price range in the industry (Q3 2024 data):

Case reference: An auto parts factory produces engine mounts, using 6061 aluminum plate CNC machining, the unit price is 42 yuan/kg, if you switch to ordinary carbon steel plate (unit price 12 yuan/kg), the cost can be reduced by 71%, but corrosion resistance needs to be sacrificed, and finally the aluminum plate is selected according to the product use environment.

3. CNC sheet metal processing quotation calculation method: I can calculate it myself

3.1 Core Formula: How to Calculate {CNC Machining Hour Rate}?

The core of the processing quotation is the accounting of labor expenses, and the common formula of the industry:

Total quote = material cost + (machining man-hours × man-hour rate) + surcharges

Among them, the working hour rate is affected by the type of equipment:

• Ordinary CNC milling machine: 80-120 yuan/hour
• Laser cutting machine: 150-250 yuan/hour
• 5-axis CNC machining center: 300-500 yuan/hour

For example: a part needs to be laser cut to 3mm stainless steel plate, the processing time is 2 hours, the material cost is 800 yuan, and the additional cost is 100 yuan, then the total quotation = 800 + (2×200) + 100 = 1300 yuan.

3.2 Cost Optimization: {Plate Utilization Calculation} Tips

The utilization rate of the plate directly affects the material cost, and the calculation formula is:

Utilization Rate = (Actual Material Area ÷ Total Plate Area) × 100%

The industry average utilization rate is 85%-90%, which can be increased to 92%-95% by optimizing layout. For example, nesting multiple small parts can reduce scrap, and a furniture factory has improved sheet utilization from 86% to 93% and reduced material costs per batch by 8% by optimizing CNC cutting nesting.

3.3 Additional Fees: {Design Complexity Surcharge} vs. {Surface Treatment Surcharge}

• Design complexity: conventional shapes (round, rectangular) are not marked up, complex special-shaped parts (such as curved surfaces, porous structures) are increased by 20%-50%, and parts with a hollowing rate of more than 60% are increased by more than 50%;
• Surface treatment: anodizing (10-20 yuan/square meter), painting (15-30 yuan/square meter), electroplating (30-50 yuan/square meter), the price of different processes varies significantly.

3.4 Accuracy Impact: {Accuracy Level and Price}

The higher the precision requirements, the higher the processing difficulty and cost:

• Normal accuracy (±0.1mm): No markup
• Medium Accuracy (±0.05mm): 10%-20% markup
• High Precision (±0.01mm): 50%-100% Markup

A medical device part requires ± 0.02mm accuracy, and CNC machining is quoted 75% higher than normal accuracy due to the need for three additional precision calibrations.

3.5 Pitfall Avoidance Guide: {Quotation Detail Analysis}

When you get the quotation, you need to focus on checking the following items:

1. Material specifications: clarify the material, thickness and size of the board to avoid shoddy quality;
2. Processing items: Specify specific processes such as cutting, drilling, and grinding to prevent omission charges;
3. Additional fees: confirm whether surface treatment, packaging, logistics are included;
4. Warranty terms: accuracy guarantee, delivery cycle, after-sales maintenance policy.

4. Industry-Specific CNC Sheet Price Cases: How to Choose for Different Scenarios?

4.1 {Aerospace Sheet CNC Quote}: Cost Balance Under High Requirements

The aerospace field has extremely high requirements for the strength and corrosion resistance of plates, and commonly used titanium alloy plates and composite plates:

• Case: An aviation parts factory purchased Ti-6Al-4V titanium alloy plate CNC machining, with a unit price of 480 yuan/kg and a processing accuracy of ±0.01mm.
• Key: The industry is less price-sensitive and focuses more on quality and stability, with bulk purchase discounts typically not exceeding 5%.

4.2 {Automobile mold plate price}: Cost-effectiveness is prioritized

Commonly used P20 mold steel and 718H alloy plate for automobile molds, the price range is 25-50 yuan/kg:

• Case: An automobile mold factory produces bumper molds, using 45# carbon steel plate CNC machining, with a unit price of 16 yuan/kg, a processing cycle of 15 days, and the total cost is 40% lower than that of imported mold steel, and meets the service life requirements (about 100,000 stamping).

4.3 {Cost of electronic product shell plate}: Lightweight and appearance

Aluminum plates and acrylic sheets are mostly used for electronic product shells, which are medium in price and flexible in processing:

• Case: A mobile phone manufacturer produces tablet shells, using 5052 aluminum plate CNC cutting + anodizing, the unit price is 38 yuan/kg, the cost of a single equipment shell material is about 25 yuan, if you switch to stainless steel plates, the cost will increase to 42 yuan, and the weight will increase by 30%, affecting the user experience.

4.4 {Medical device special plate cost}: Hygiene and precision are up to standard

316L stainless steel plates and titanium alloy plates commonly used in medical devices must meet medical-grade hygiene standards:

• Case: A medical device company manufactures surgical instruments, using 316L stainless steel plate CNC machining, with a unit price of 42 yuan/kg, which is 30% higher than ordinary 304 stainless steel plate, but has stronger corrosion resistance and biocompatibility testing, meeting ISO 13485 medical standards.

4.5 {Market price of architectural decoration board processing}: pay equal attention to scale and aesthetics

Carbon steel plates and acrylic plates are commonly used in architectural decoration, with large batches and high requirements for appearance:

• Case: A commercial complex decoration uses 3mm carbon steel plate CNC hollow cutting, the unit price is 14 yuan/kg, the surface painting treatment (25 yuan/square meter), and the batch purchase of more than 10 tons enjoys an 8.5% discount, and the final total cost is reduced by 12% compared to small batch purchases.

5. Yigu Technology's view

As a company that has been deeply involved in the CNC machining field for 12 years, Yigu Technology believes that the core of CNC sheet price selection is "demand matching" - rather than simply pursuing low or high prices. Carbon steel plates and ordinary aluminum plates can be preferred for general industrial scenarios to balance cost and performance; high-end precision scenarios (such as aviation and medical) need to decisively choose titanium alloys and high-grade stainless steel to avoid affecting product reliability due to material issues. At the same time, it is recommended that buyers establish long-term cooperation with suppliers to reduce costs through bulk procurement and shared demand forecasting, and be sure to clarify material standards, precision requirements, and after-sales terms in contracts to avoid later disputes. In the future, with the development of composite material technology, CNC sheet prices will show a trend of "price reduction for high-end materials and stable for ordinary materials", and enterprises can lay out new material applications in advance to enhance product competitiveness.

6. FAQ:

1. Bulk purchase of CNC sheets, what is the minimum amount to get a discount?

A: The industry's regular minimum batch is 500 pieces or 1 ton, which can enjoy a 90% discount; For more than 1000 pieces or more than 3 tons, the discount can be as low as 8.5%, which needs to be negotiated with the supplier.

2. How much is the difference in processing price of the same plate of different thicknesses?

Answer: Taking 304 stainless steel plate as an example, the unit price of 1mm thick processing is about 28 yuan/kg, 5mm thickness is about 35 yuan/kg, and 10mm thickness is about 42 yuan/kg, and the unit price increases by an average of 7%-10% for every 1mm thickness.

3. Is the surface treatment cost calculated by area or weight?

Answer: In most cases, it is calculated according to the area (such as anodizing 10-20 yuan/square meter), and some complex parts are priced according to weight (such as electroplating 3-5 yuan/kg), and the accounting method needs to be clarified when quoting.

4. How much more expensive is high-precision CNC machining than ordinary precision?

A: ±0.05mm accuracy is 10%-20% more expensive than ordinary accuracy (±0.1mm), ±0.01mm accuracy is 50%-100% more expensive, and if you need to achieve micron-level accuracy (±0.001mm), the price may be 2-3 times higher.

5. Does the regional price difference have a significant impact on CNC sheet prices?

A: Obviously, due to the concentration of supply chains in the Yangtze River Delta and Pearl River Delta regions, the price is 5%-10% lower than that in the inland areas.