Aug 18 2016

Do I Need a Formal Education to use a CNC Machine?

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CNC machining is a hobby to many people but it is a profession to other individuals. There are classes and schools dedicated to teaching people about CNC machines. You may ask yourself whether it is necessary to get a formal education regarding CNC machines in order to use one. While it is not necessary, it certainly helps. Operating any CNC machine is by no means self-explanatory and professional CNC technicians are required to go through training. Hobbyists can and often do figure things out on their own but if you have the time and budget to take a few classes they will certainly increase your knowledge of CNC machines.
There are a lot of technical schools out there but not all of them will offer training with the type of CNC machine you want to use. Most schools that do offer training programs will not train you in a single classes; multiple classes are taken to break the training process up into several sections. Beginning classes may not even offer any hands-on training with the machine; actually working with the machines can be reserved for later classes in the training program.

CNC router machine

CNC router machine

Beginner classes will teach students about the basic concepts of CNC machines. Remember that even if you know a bit about CNC machines the same may not apply to everyone in the class. Just because the information the class is going over is not benefitting you does not mean no one in the class needs to learn that material. It may be boring at first but you have to get past the basic courses before you can move onto the real fun stuff. These courses will frequently cover the limitations of CNC machines. You will be taught to consider factors like tool selection, spindle speed, cutting sequences and clamping and positioning before you turn your machine on.





Reviewing the function of G-code and how it interacts with a CNC machine is also commonly covered. Examples of coursework in beginner classes includes establishing how you will choose the right tool for a project (considering factors like safety and efficiency), installing handling devices and tools, loading G-code into the machine’s software and producing sample parts to make sure they match specifications and operation instructions given to you.
Advanced classes are where you start to really use the CNC machine, now that the beginning classes have taught you the basics of how to operate it. Initial advanced classes tend to start with reading, comprehending and making CNC programs for basic tasks like drilling, threading and turning. Later classes will cover more complex tasks like machine adjustments, program editing and creating new command syntax. Coursework in these classes may involve things like comparing test results to identify editing needs, regulating and adjusting coolant flow, repairing or replacing damaged tools and taking steps to prevent damage to tools, the CNC machine and the material being used for your projects.

These are generalizations of how a CNC machine training program is run and each institution may do things a bit differently but most places will do something along these lines. For a hobbyist it is not 100% necessary to take classes for CNC training but you will learn any subject faster when it is taught to you, compared to just figuring things out for yourself. Even if you do not have the time or budget to attend formal training at a school you should still look up tutorials and other help videos online to get a better idea of where to start and what to do. Everyone was a beginner at some point and they all had to learn somehow; determining the most effective and efficient way of learning is up to you.


Aug 11 2016

CNC machine Attachments

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When you first buy (or build) a CNC machine your primary concern when working on your budget is likely going to be figuring out what the best quality parts you can afford are. Every machinist, from professionals to hobbyists, wants to get the best CNC machine that they can in order to make machining processes as smooth as possible. While you should certainly concern yourself with the necessary parts of the machine first, so that it can actually run, there are additional considerations you can take. Attachments (or accessories, add-ons, or whatever you wish to call them) may not technically be essential to the running of a CNC machine but once you start using them they can be so beneficial that they will certainly start to feel like necessary components.

Some attachments are so common that many machinists would likely argue that they are essential components to any CNC machine. Ruin boards are a great example of an attachment that fit into this category. Image that you have your CNC machine set up and you are ready to machine your first project on your nice, new t-slot table. With what you just paid for that t-slot table you can picture what a nightmare it would be to accidently cut right into the table and destroy it. Keeping a ruin board between the table and your material should stop this from ever happening. Ruin boards do not need to be too thick; usually something between ⅛” and ¼” will work fine. New machinists may want to use a thicker board to leave more room for error.

CNC machine clamps

CNC machine clamps

Clamps are another great, yet simple, attachment that most basic CNC machines should include. Any level of precision machining will require you to hold your material still. There are a lot of ways to do this and clamps are one of the easier and more cost efficient methods. Sometimes you may have other methods available; t-slot tables utilize t-slot nuts, step blocks, step clamps and other implementations but it can be a hassle to find pieces that fit the specific table you are using. Making a clamping system of your own can be much more effective. Be creative and try to develop an easy-to-use system that works well with your equipment and set-up.
In some cases clamps may not be a good hold-down method because the item you are machining is too small. When you find that your clamps are too large, a milling vice is an excellent alternative tool. While a regular vice could be jury rigged to your table, a milling vice is designed specifically to work with a CNC machine table and they tend to be extremely precise. There are many different types and brands of milling vices in many different sizes so determine your needs and do a bit of research before committing to anything expensive.





Once you have a hold-down system in place you can start actually machining. On any project you want to make sure that everything has been machined accurately and there is no set of tools better for this than a pair of calipers. Digital calipers are the way to go for their extreme precision; 0” – 6” calipers will work fine for the vast majority of measurements you need to take while examining the finer details of projects. Cheaper calipers work fine but like any other tool you will want to go for the higher end of tool quality and price range as your budget allows.

 air sprayer for cnc machine

air sprayer for cnc machine

During and after machining, chip evacuation will be one of your primary concerns. Using an air sprayer is the best way to clear out chips while your CNC machine is running. Any standard air compressor with a trigger nozzle can do this well. Clearing away chips during the cutting process is often a critical procedure. After your machining has been completed you will want to use a shop vac’s powerful suction to get all of the chips out of your work area, leaving everything crisp and clean for your next project. Any time you are working with chips, and when using a CNC machine in general, always remember to wear safety goggles.


Jul 7 2016

Climb and conventional milling secrets that you should know

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When a cutter moves through material it can mill up (conventional milling) or down (climb milling). Many machinists use climb milling for most, if not all, of their CNC projects. Climb milling is known for producing better surface finish than conventional milling and overall does have more advantages than conventional. However, climb is not always the better of the two options and any machinist should know that there are times when conventional is preferable, and when those times are.

Climb and Conventional Milling

Climb and Conventional Milling

Using climb milling, each tooth on your cutting tool makes contact with the material you are working with at a defined point and moves out, cutting thinner parts of the material until it is no longer touching the material. So, the width of the material being cut starts at the maximum length and decreases to zero as the cutter moves. This causes chips to be thrown behind the cutter, making chip removal an easier process while machining. Tool life is also extended because each tooth on the cutter is not rubbing against the material. One of the major downsides of climb milling is that it can potentially produce a lot of backlash. As a result this method should mainly be used on machines that can eliminate large amounts of backlash and it may not always be usable with older CNC machines.
Conventional cuts in the opposite direction of climb. Using conventional milling, the teeth of the cutter will start at zero thickness and work their way up to the maximum thickness that you are cutting. When first making contact with the material your cutter does not even cut the material; it slides across the material surface until enough pressure is built up for the tooth to dig in and begin cutting. This causes the work material to become hard and somewhat deformed and also causes cutters to dull faster than when using climb. The sliding and biting of this cutting process also tends to leave an inadequate surface finish on work materials. On the upside this process does not generate anywhere near as much backlash as climb and is a perfectly sound cutting method on almost any CNC machine. The two methods do not have to be used independently either; climb can be used for rough passes while conventional milling is used for finishing passes.
Climb does have a few distinct advantages over conventional when your machine can manage it. As mentioned before, your tool life will be longer, surface finish will be better and chip removal is much easier. Additionally, you do not need as advanced of a hold-down system. Climb exerts force downwards instead of upwards like conventional milling. You can also use higher rake angles while climb milling, saving you a little money on the amount of power needed. Just do not forget about the excessive backlash when looking at all of the positives of climb milling.
When using climb milling, deflection can causes some problems with surface finish. Climb cutting causes tools to deflect, deforming the surface finish of projects and leaving you with less than adequate results. If you run into this issue try switching to conventional cutting; that will likely make a big enough difference to correct any issues you are having with maintaining a good surface finish. While conventional cutting can help it will not always fix your problems. If you have tried climb cutting and conventional cutting and are still having issues you can decrease deflection further by reducing the depth of your cuts. Using a small amount of your cutters diameter will make it less likely that you will experience any deflection.


Jun 23 2016

Easter egg design with Eggbot & CNC Egg Decorating

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Easter egg design with Eggbot & CNC Egg Decorating

Decorating eggs is an age old past time for children, especially in the spring when it starts getting close to Easter(easter egg design). Traditionally, you would take an egg and color it by hand. But like many older past times, this task has been made faster, better and more efficient through the innovation of modern technology. This particular CNC machine may have a very specific function but it is a basic machine that serves as a good way to teach CNC technologies to children and young adults. The name of this machine is the EggBot.

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Jun 16 2016

3D printer fabrication with CNC machine

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3D printer fabrication with CNC machine

There are a decent number of hobbyists out there who build their own machines from parts instead of buying a whole one. Some folks enjoy buying individual parts from the store or suppliers to build the machine from scratch while others just want to buy a DIY kit and assemble that; your options regarding these choice might be limited depending on what type of machine you are working with and what kinds of options are available for that type of machine. S hobbyists who already have a CNC machine, 3D printer or something similar may want to try other machines out but find that buying or building a whole new machine is outside of their budget. If you are creative enough you can build just about anything using your machines so why not 3D print a CNC machine, or use a CNC machine to make a 3D printer?

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