Many people are considering CNC machines because of their versatility. It's because of CNC milling and CNC turning that work effectively with various raw materials to produce finished parts. However, many do not understand the vital selection of raw materials for CNC machine frames. Design engineers have many options when developing prototypes and commercial products.
Key considerations when choosing CNC machine Frames
There are two key considerations in CNC machine frames:
- Stiffness/ Rigidity: The good machine frame should resist distortion because there is cutting and too much force applied.
- Damping: The machine frame should be quick enough to cause vibrations and cause dampening unless there is bad surface finish chatter in the machine work.
There are specific materials considered in CNN machining. Steel is quite stiff with poor damping capability. Therefore, they are rarely used. Conversely, cast iron tends to have excellent stiffness and dampening. An exception is only available if there is any other mechanism that can be used for dampening than the material and sheer mass, such as steel weldments topped with epoxy granite.
Epoxy granite consists of various rock sizes, from sand to small pebbles and epoxy resin mixture. When vibration happens, friction occurs in the surface area between the rocks and resin. Rocks of different sizes resist various vibration frequencies to different extents. Epoxy granite is a good dampening material; however, it has little strength, thus making use of welded steel containers of epoxy granite enhances its strength.
Aluminum is also a common DIY machine frame material. The most common are aluminium plates and aluminum extrusions. Aluminum is more desirable for use because of its dampening standpoint, unlike steel. It also doesn't have to be stress relieved because of its desirable property. Though cast iron and steel are good materials, they have internal stresses which lead to distortion when machined.
How to choose the best CNC machine frames material
When choosing CNC Material that works best, we always advice our customers to consider the environmental condition and the type of forces the material will be subjected to. There are many variables to consider, but the above areas influence materials sustainability greatly.
- Moisture: Do the CNC machine frames need to withstand fresh or salt water? Some metals resist corrosion naturally, while others need additional treatment linked to playing, anodizing, or painting.
- Strength: materials differ in their strength; therefore, knowing the tolerance limit of each is critical. There are four ways to determine the strength of a material. That is toughness, elasticity, tensile strength, and compression or load bearing. Always consult the manufacturer in advance to understand the technical information.
- Heat: All materials contract and expand in heat situations, which could affect the material used in CNC machine frames if subjected to cooling and heating cycles. To prevent failures of the frames, it's ideal to use a thermally stable material at high temperatures.
- Corrosion Resistant: Material corrosion can result from water, oil, acids, reagents, alcohols, salts, and more. When checking for CNC machine frame material, check for the datasheet of the material and its response to weather and chemical exposure.
Though there are numerous materials to consider for CNC machine parts, we have the best alloy materials to deliver the best for your project. We are well equipped, experienced, and professional in what we do. If you seek professional help with CNC machine frames, we are ready to help; contact us.