Introduction(metal corrosion resistance chart Claire)
- source:NEWRGY CNC Machining
Machine Purchase Price
The base purchase price of a new CNC machine can range from tens of thousands to hundreds of thousands of dollars depending on the size, capabilities and features. Entry-level machines designed for prototyping and hobbyists can cost as little as $5,000 while industrial 5-axis machines used for production can cost over $500,000. Some key factors that affect base CNC machine cost are:
- Number of axes – More axes (3, 4 or 5) allow more complex geometries but cost more.
- Travel distances – The larger the X, Y and Z travel distances, the larger the work envelope and part sizes possible.
- Spindle power – More powerful spindles allow faster material removal rates.
- Control system – Simple controls suffice for 3-axis milling while 4 and 5-axis machining requires more advanced software.
- Size – The overall physical size of the machine impacts cost.
- Precision and accuracy – Higher precision ballscrews, way surfaces, spindle runout all improve precision for a premium.
- Automation – Workpiece handling automation like pallet changers increases costs.
- Brand and options – Brand reputation and additional options like probing and coolant systems also add cost.
Pre-purchase considerations like machine size, spindle speeds, power requirements, as well as options and upgrades will impact the total machine investment. Carefully analyze part size requirements, production volumes and accuracy needs when selecting a CNC machine to avoid overbuying or underbuying.
Setup, Delivery and Installation
The process of getting a CNC machine operational in your facility also incurs costs. Most machine shops either integrate the machine themselves or contract setup and installation to a specialized rigging company. If contracting a rigging service, you can expect to pay:
- $500 - $1500 for local delivery within 50 miles
- $2000+ for long distance transport exceeding 50 miles
Other setup costs may include:
- Electrical connections and wiring for power supply
- Leveling and securing machine to floor
- Assembly of any detached components
- Installation and testing of any options and upgrades purchased
- Initial cleanup and lubrication
Proper setup and installation ensures the machine has the stability, vibration isolation and electrical supply to operate optimally for precision cutting. Taking the time upfront to get the machine completely ready for production will pay off in the long run through consistent and accurate machining.
Tooling and Workholding
Cutting tools, tool holders, vises, clamps, fixtures and other workholding equipment are required to actually machine parts on a CNC. The costs of acquiring the necessary tooling add up quickly. Common tooling expenses include:
- End mills, drills, inserts and other cutting tools
- Tool holders like shrink fit and hydraulic chucks
- Vises, fixture plates, clamps and other workholding
- Tool storage, carts, racks and organization
The types of tooling required depends heavily on the materials and features to be machined. Complex 3D surfaces and tight tolerance features often necessitate custom designed fixtures as well. Budgeting extra for tooling and workholding is advised when first adopting CNC machining to prevent workpiece errors and subpar surface finishes from inadequate fixturing.
Software, Programming and G-Code
CNC machines require CAM (computer-aided manufacturing) software to convert CAD models into machining instructions called G-code. The costs of obtaining programming software and creating G-code for parts include:
- CAM software purchase or subscription fees
- CAM training and learning curve time
- Programming time (can be hours per part program)
-CAD model preparation and machining simulation
-G-code simulation, editing and optimization
The complexity of the machined parts determines the necessary effort to program them. Parts with complex 3D surfaces, 5-axis motion, tight tolerances or exotic materials benefit from advanced CAM software and an experienced programmer to efficiently translate them into error-free G-code. Many machine shops estimate programming time at 2-3x the required machining time.
Once installed and tooled up, a CNC machine requires additional operating expenses as well:
- Operator wages
- Training new operators
- Electricity usage
- Cutting tools and tooling replacement
- Coolants, lubricants and shop supplies
- Machine maintenance and occasional repairs
- Renovations for new equipment
- Increased shop floorspace
Factor in these ongoing costs of running a CNC machine to determine the full operating costs compared to the increase in production throughput. CNC automation often reduces manual labor costs but introduces other variable costs that are recovered over time through production. Pay close attention to consumable tooling costs which can pile up quickly in high volume production environments. Overall, estimating operating costs as a percentage of machine purchase price per year is reasonable.
Incorporating CNC machining involves substantial upfront investment to acquire machine tools, tooling and workholding fixtures. Additional costs are also incurred during installation, programming part designs, and ongoing operation. Carefully researching and budgeting for the complete costs beyond just the initial machine purchase price allows fabrication shops to strategically add CNC capabilities without breaking the bank. With an accurate assessment of total cost, shops can target higher efficiency CNC machines tailored for their part needs and workloads. CNC Milling CNC Machining