cnc milling services | ace laser technologies, elk river, mn 55330
Ace Laser Technologies provides quality CNC machining services. Typical tolerance of +/-.002" and down to .0002" if needed on special applications. Our bed capacity is 40" x 20". Materials worked with include Aluminum, SST, Carbon Steel, Brass and all plastics. We have full CNC automation so we welcome jobs from 1 off prototypes to many thousands. Our knowledgeable engineering team can import your CAD drawing and create the parts to your specs or help with your design if needed. We do government and aerospace projects on a regular basis so we are familiar with AS9102 inspection. We also offer Laser Cutting, Welding and Etching services on 3 lasers. Typical tolerance of +/-.002". Material processed include steel, SST, aluminum, electrical steels, brass, plastics and wood. Rush service is available if needed.
cnc milling process guide 2019: full process explained
In one form or another, the CNC milling process is involved in the vast majority of tangible products in modern industrial manufacturing. While it only directly makes a small fraction of parts, its the most common method to create tooling, so its difficult to avoid altogether. In the process of bringing new products to life, CNC milling operations almost always come into play and its good to be familiar with a thing or two about CNC milling process.
Milling operations involve taking a spinning sharp cutting tool and moving it through a solid block of material to whittle away at it until you have the final shape you want. Unlike that eccentric cousin of yours who carves pumpkins with a Dremel tool, milling machines are precision pieces of equipment that securely hold that block of material in place and move it or the cutting tool relative to each other with a great deal of accuracy. The CNC part (Computer Numerical Control) introduces a computer into the process to automate the precise movements in very complex ways. As long as the tools are sharp and the machinery can by physically oriented for the tools to reach, computers can drive CNC mills through incredibly intricate motions to carve out the parts you need.
There are a few options for types of CNC milling machines that can reach nooks and crannies in different ways. The most basic type is a 3-axis machine. This typically involves a machining bed that holds the block of material, which can move in an x (left to right) and y (front to back) direction. The third z (up and down) direction comes from the spinning tool head, the spindle, moving downward toward the machining bed. Machining on a 3-axis system can achieve a great deal of surface complexity and is plenty sufficient for creating tools for molding, casting, and forming processes like injection molding, thermoforming, rotomolding and the like. With the undercut limitations of those processes, a 3-axis CNC machine will always be able to achieve the tool shapes required.
For other tools and parts where the spindle must be able to reach the block from multiple sides, a 5-axis CNC mill is needed. This would have all the same movements as a 3-axis machine, plus the machining bed can tilt and rotate as well. This lets the cutting tool access the block of material from any angle.
In both types of machines, the movements are relative. Some may move the machine bed. Some may, instead, move the cutting tool. In any combination though, its the relative angle and reach of the tool and material that defines the type of machine. There are also other less-common hybrid versions that allow some repositioning of the machining bed, but theyre not true 5-axis machines if these positions arent computer controlled while the material is being cut.
So, what can you cut with a CNC mill? Well, basically any rigid material as long as its bigger than what you want to end up with. Metals of all sorts are great from soft aluminum to high strength tool steel alloys. Hard plastics machine nicely as well.
One fantastically versatile material that is somewhat unique to CNC milling is REN or modeling board. This is a composite polymer material extremely well-suited for machining that is heat resilient and relatively low cost.
In product development, REN is widely used for prototyping processes to fit-check designs that would otherwise be made of much more expensive materials. It can also be used to make temporary tools for casting, short-run tools for thermoforming, forms for gel coat fiberglass layups, assembly jigs and testing fixtures. Its like a swiss army knife for product development model builders.
Now, whatever the material, it only becomes the shape you want in the end by applying cutting tools. There is a lot of engineering that goes into making cutting tools with specific properties fitted for long life and fast cutting speeds for specific materials. For now, though, well just talk about big vs small and categorize the overall shape.
Bigger tools remove more material but generally must move through the material a bit slower. Smaller tools naturally remove less material and can progress through the material a bit faster, but they allow for finer features and things like smaller radius corners. Some specialized tools may be required for undercuts and keyways. The overriding focus for tool selection is on minimizing machining time. The ideal case is to select a single relatively large tool that can remove a lot of material quickly and achieve the desired shape. Its far more likely though, that your part will need to have tools changed out during the machining time to minimize cutting time or get a certain feature. This is where a proper design fit for CNC milling production can have tremendous value.
Designing parts for CNC milling operations must consider allowing use of the largest tools and fewest tool changes, while also protecting the tools from breakage. How can a design protect a tool from breaking? Great question. Were glad you asked!
If youre not already somewhat familiar with milling, youll see in the images above that the tools look similar to drill bits. Where drill bits only cut material at the tip moving down into a material, milling tools cut both at the tip and at the side primarily at the side. So when it moves sideways through the material its cutting, the milling tool can be flexed away from the side its cutting at the same time its rotating at a high rate of speed. This can stress and break a tool if its long and slender. Avoiding long, slender channels, small inside radius edges, or other features that would require a long and unsupported tool will make a part much more easily manufacturable. If these features are in a part design, it can both increase production costs and limit the number of CNC milling manufacturers willing to produce it.
Tools can break apart and they can also break the part. Just like how the milling tools can be stressed and flex away from the material, the material can flex away from the tool. Long, thin and unsupported features in a part can bend or may even break off during a milling operation. They are to be avoided.
Unlike most processes, CNC costs for prototyping and production are identical. The process is the same in both cases. Like most production processes, youll pay a little premium for setup and amortize those costs over higher or lower volumes. Regardless, the cost structure is consistent between prototype and production runs. Under all typical circumstances, no capital investment in specialized tooling is required. In fact, CNC milling is the most common method used to produce the initial capital investment tooling for other high-volume processes.
Widely accessible and versatile, CNC milling shops can be found in just about every city. Some very uncommon specialized requirements may narrow possible vendors such as extremely large part sizes or requirements for machining specialized materials like metals containing lead. When choosing a vendor for your project, the quantity and type of equipment they have (3-axis vs 5-axis) and their experience will qualify their capability. The rest is pursuing a business arrangement that matches your needs for volume, delivery & payment terms, and value-added services you may require. There is skill in setting up and maintaining the machinery, but a computer controls the precision and consistent operation of the machinery. Finding the right CNC milling vendor is all about finding an agreeable company to work with that has the machines your product requires.
The 3D CAD geometry modeled on a computer is translated into tool paths and speeds by CAM software. A tool path is the specific continuous chain of movements of the spinning cutting tool through the block of base material to be cut. The CAM software selects tools and optimizes tool paths for the shortest cutting time. The computer then interfaces with an automated CNC milling machine by sending it a stream of numerical data that determines the position of each axis at each moment in time and other parameters for the cutting tool.
Marilyn Monroe revived its allure in the 1950s. In the 1980s, it was again made famous by none other than the likes of supermodel Cindy Crawford and Ms. Pac Man. Beauty marks are technically a blemish but revered for their character. Similarly, tool marks are a blemish but cmon man! Nobody in their right mind wants a bunch of swirly scratches all over their parts! Theyre abrasive, disruptive, and make a part look incomplete. If you leave these in your injection mold tooling, youll see a bunch of lines and scratches in your plastic parts. Not good.
Luckily, there are some common methods and practices for removing tool marks from CNC milled parts to make things look much better. A common quick, dirty AND effective method is bead blasting. This is the process of shooting little bits of glass, sand, aluminum oxide, crushed walnut shells, or other media at a surface with jets of compressed air. This can quickly knock down small raised imperfections and smooth things out, leaving a lightly textured even surface behind. Softer blasting media will leave a smoother finish overall, but a high polish requires the skilled hands of an experienced toolmaker. This is a manual hand-polishing process using fine polishing stones, polishing paste compounds, and buffing wheels. With this method, even a mirror smooth finish can be achieved.
This article has been invaluable in giving insight to a new junior employee that we have great hopes for in our metal shop. Articles like these really help people to fully understand how things work in finer detail.
Its cool that the machining bed can tilt and rotate with a 5-axis machine because that means itll be able to make more complex shapes. If it can reach all kinds of angles, itll be a lot easier. Ive been thinking of using a CNC machine for my projects but I wasnt sure what all the different types meant. Thanks for explaining!
CNC machining does seem like a tricky thing to do. I like that you explained that the cost of CNC will be factored in by a few different things. I didnt realize that the city and types of equipment used could affect the price a lot.
Its amazing that you can cut basically any rigid material with a CNC milling tool! Thats really helpful because then you can do virtually any project imaginable! Im definitely going to think about getting one.
Ive recently considered adding a CNC machine to my tool kit for some of my hobby projects. It is interesting that any rigid material can be used in a CNC mill. I may consider also adding an angle head to my setup as well.
I thought it was interesting when you explained that a CNC machine is great for cutting various metal materials. I would imagine that the bit that is used on these drills would have to be pretty strong. It would be interesting to learn more about the spindles that are used on these drills.
Its good to know that milling machines are precision pieces of equipment because you know that you can trust them more. They take out a lot of the human error that used to come with carving things. Ill keep this in mind next time I need to make something.
Its really cool that nearly any material can be used in CNC milling as long as the material is larger than the final product and is rigid. Personally I think that CNC milling could save small business owners a lot of time and money in certain cases. I think a lot of times small business owners think that CNC is only for big brand companies however I think that they could benefit if they were to invest a little time in researching CNC options near them.
Thank you for pointing out that CNC milling machines are precision pieces of equipment that securely hold a block of material in place. I assume that carpenters would need the use of a good CNC machine if they are doing a lot of work. Its good to know that CNC stands for computer numerical control.