The following are some of the most popular questions asked by our readers:
How many types of CNC machines are there?
There are several types of CNC machines. There is the general purpose machine which is usually referred to as a router or milling machine. These machines have been around since the beginning of time and they work very well today.
They do not require any special skills to operate them so anyone can use one. Some of these machines are capable of doing everything from making small items like keys to large objects such as cars.
CNC Machines come in various sizes and capabilities. Smaller machines are often called CNC routers and they typically cost less than $1000. Medium sized machines can be called CNC mills or CNC lathes and cost between $2000-$5000.
Large machines can be called CNC routers, mills or lathes and cost over $10,000.
What is the difference between a CNC Router and a CNC Mill?
A router is a general purpose tool used for cutting out shapes from wood or other materials. A mill is a specialized tool designed to cut parts from larger pieces of material such as metal. Most routers are operated with hand tools while most mills are operated using electric motors.
Large machines can be called CNC routers or CNC mills and cost over $10,000. You may want to consider buying a tool that combines all three functions. For example, you could buy a router/mill combo that includes a router table, router base and router head.
What type of materials can I use with my CNC machine?
You will need to purchase special equipment if you plan on using wood for your project.
What is the difference between ball screw and acme screw?
Acme screws are more precise and have a more linear motion than ball screws. This makes them better for some projects and some machines use both types of screws on the same machine. Acme screws are better if you need to position something with a high degree of accuracy such as engineering work or engraving.
Acme screws do not hold position as well when not under load. Some types of plastics can be used to make parts but you cannot drill into them. A CNC machine can only drill into soft materials like wood, plastic and aluminum. If you need to make holes in metal you will need to buy a different drill bit or use a mill instead of a router.
How large of objects can my CNC machine produce?
The maximum size of the object that your CNC machine can produce is determined by the size of your work area. Ball screws hold their position better when not under load, which makes them useful when cutting or milling.
What kind of bearings do I need to buy?
The size of the bearings that you need depend on the size of your machine. Most machines use 8mm diameter bearings while some use 10mm. You will also need to know the width (or distance between the inner edges) so that you can buy the correct sized bearings for your machine.
This is the surface on which you will mount your material. A common work area size is 30″x24″. This means that your CNC machine can cut an object up to these dimensions from the material that you mount to the work area. The maximum size of your finished object is limited by the length of your tooling.
What types of projects can I make with a CNC machine?
What kind of nuts and bolts do I need to buy?
Most CNC machines use M6 or M8 nuts and bolts. You will need to know the length of your bolts so that you can buy the right sized ones for your machine. Most bolts are 12.7mm or 1/2 inch long but you may need other sizes so be sure to measure all the bolts on your machine before you go shopping.
You can make a wide variety of parts using CNC. A good example is window sills. The parts are large so you need a large machine.
You can also make models and prototypes to help makers come up with new inventions. You could even prototype new video games!
What types of materials can I use with my CNC machine?
CNC machines can cut wood, plastic, aluminum, copper and more.
What is the difference between CNC and 3D Printing?
A 3D printer is used to make prototypes from a CAD drawing. You can make small, medium or large parts depending on the size of your printer. You must design your prototype in a CAD program and then send the file to the printer.
You cannot make last-minute changes or create tooling. You can usually also use different types of bits to cut other materials as well. You will need to know the size of the largest part that you can cut in order to buy the correct sized router for your machine. With a CNC machine you can make last-minute changes because you are moving the cutting tool, not the work piece. You can also use a mill to make tooling more quickly.
What types of materials can I use in my CNC machine?
Your machine can use wood, plastic, aluminum and other metals. It can’t cut through hardened steel so you can’t cut through a car axle but it can easily cut through softer metals like window sills.
A CNC router is used to cut large amounts of the same size parts from a material. You can make last-minute changes to your design by cutting a new part to replace any that are wrong. You can also cut custom tooling such as jigs and fixtures for other inventions.
You need to know the maximum size that you can cut in order to buy the correct sized machine for your project.
What kind of computer do I need?
What tools do I need for my CNC machine?
Most CNC machines use the same or similar tools that you would find in a metal shop. See the list below to learn more.
Cutter: A drill bit or end mill that can cut into the material. Most bits are made from high speed steel and have a cutting edge at the bottom so they can make a chip to cut with. Your bit will wear down over time.
You need a PC that runs Windows 98 or higher and has a parallel port. You will also need Internet access to buy software and send designs to your machine.
What kind of software do I need?
Inventables has the Inventable Designer Software for inventors and hobbyists. It is easy to learn and use. You can also download the SketchUp 3D Warehouse free 3D modeling software and use this to send files to your machine.
For softer metals the cutting edge will become blunted and for harder materials the bit will break. You can also use other tools such as a cut off disk in your saw, a file or even sand paper.
Wrench: Used to tighten and loosen each part so that you do not need to carry each tool with you every time that you make a cut. A tool box comes with your machine. You can also learn other 3D design programs such as Autodesk Fusion 360 or OnShape and send files to your machine.
If you need additional copies of the software, these are available for around $50 from Inventables.
What if I want to make something that is bigger than my machine can cut?
You can rent time on a larger machine at Inventables.
Starting at $2,850 you can have your own CNC router.
The smallest size machine is an X-Carve. It is great if you need to make small and simple things. It comes with everything that you need to get started.
The next size up (or add on) is the Shapeoko which makes crafting a breeze.
If you are ready for a larger project then the X-Lazer is your best choice.
What if I want to make something that is smaller than my machine can cut?
You can use a laser or water jet to cut through thicker materials. You can also send the files to a manufacturer or service to get the part made.
You can even build your own machine from one of the many kits that are available.
Of course you can also choose to buy a used machine or get help from a friend who has one. What ever you end up choosing it is sure to be an exciting addition to your workshop.
Can I send my files somewhere else to get parts made?
Yes, you can send your files to a manufacturer or service.
3D Printed parts are cheaper, but the quality isn’t as high and you can’t use multiple materials like you can with injection molding for the final tools. 3D Printed parts also take longer to get back.
What can I do with a CNC machine?
The sky is the limit! If you can draw it, you can make it with your new CNC machine. You can create models, prototypes, or even parts for your inventions.
If you’re not an inventor or don’t have an invention to create, then you can help others on the Inventables Idea Center by creating their designs for them. It’s fun and the community is great!
Injection Molded parts are high quality and you can get them back fairly quickly, but they can be expensive too.
What types of materials can I work with?
You can work with a variety of materials including wood, plastic, and metal. The process is the same, you need to create or download 2D or 3D CAD files for that particular material. The machines at Inventables cut using a wire attached to a spindle which moves in a circle at high speeds.
The material is cut by the wire passing back and forth in the path of the desired cut. You can also use a router with a guide to create linear patterns.
How long does it take to get the parts and how much do they cost?
The final price of the parts is determined by the amount of material that is used to create them. The cost per unit of material is determined by the type of material and the supplier that you choose. You can find cheaper suppliers, but you also run the risk of getting poor quality scrap for your money.
What software can I use?
You can use any of the open source programs listed in the resource section or you can pay for proprietary programs. Each CAD program uses a different file type, which makes it hard to switch between them. Most inventors find that they end up sticking with one program, rather than constantly converting files.
3D Printed parts take several hours to get back and cost around $19 per pound of material.
Injection Molded parts take around two weeks to get back and can cost anywhere from $0.50 to $5 per unit depending on the size and shape.
I’ve never used a computerized machine before. Is it hard to learn?
What else do I need to create my designs?
You will need a steady hand and lots of patience for the more intricate parts. You will also need a lot of time since the machine can’t work for you.
Most of the programs have a learning function which allows you to start simple and work your way up. The key is to start with a program that uses the same file type as the machine you are trying to use. If you want to send your files to someone else, you need to make sure their program can read the file type that you are using.
To save time and confusion, most people just use one program. A helping hand to load and unload parts is always a great idea too.
What does it cost to get started?
If you have an idea for a product, then you can quickly and easily make a prototype to prove that it will work. Then it’s just a matter of creating a final version to send to a factory to get mass produced.
How does licensing a product work?
Machines at Inventables
At Inventables you can use any of the following machines:
Proto-pasta Magnetic Iron Pasta Machine ($50 per month – $500 security)
This machine is used to create gears, motors, and other metal parts using a magnetized pasta. You place pieces of fiberglass soaked in epoxy resin into the hopper.
If you don’t want to go through all the work of creating, manufacturing, and selling your invention yourself, then you can license it to other companies. They will create a version of the product and sell it under their brand name. You will be required to come up with a royalty rate that the company must pay you every time they sell the product.
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- The C3 framework and representation of global citizenship in state standards (A Rapoport – Research on teaching global issues: Pedagogy for …, 2020 – books.google.com)
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- The Techne-Analogy in Socrates’ Healthy City: Justice and the Craftsman in the Republic (SR Hemmenway – Ancient Philosophy, 1999 – pdcnet.org)