Nowadays the CNC is an integral part of our daily life so much so that the majority of the machines we use are CNC. Here is some information about the 3D Cnc
3D printing is the technology that allows to create real objects starting from 3D drawn files.
It is taking rapid prototyping to a new stage: a 3D printer can realize objects of any size and can be kept on a desktop, right next to the computer. Here is a bit of knowledge to understand why one should think of buying a 3D printer for an office, business or even for private home.
There is more than a way to create with a 3D printer and every of them has a different history. The main two, FFF and SLA, have the same goal but different materials and techniques to work. They mainly come from the 70’s, when they have been invented to cope with the big industries request to produce fast prototypes. Nowadays more ways are being added on a daily basis, but the mentioned two are still the most common and reliable.
The FABtotum has been projected to give users a multi-function tool that opens to a wide range of operations that will increase in the future. FFF 3D printing, 3D CNC milling and 3D scanning are the starting 3 tools developed by the founders of the company, back in 2011. Five years later there are already new upcoming add-ons: Laser engraving and SLA 3D printing are being tested.
CNC stands for Computer Numerical Control, in this macro are enclosed all those machines that are precisely controlled numerically.
The CNC milling machines are very particular and useful in a variety of fields; For example you can cut a metal plate or wood according to a precise plan, dig to create a three-dimensional object (even sculptures), create printed circuit boards, etc.
While the 3D printer works for addition, by adding layer upon layer to create the object, the CNC milling works for subtraction. It starts from a block of wood or metal and goes to sculpt the drawing through the movement of a spindle. The milling process is divided into two phases: a roughing operation, in which the milling cutter is provided with a tip of very coarse and not very precise, that has the purpose of rough the block, and finishing in which the spindle is fixed a smaller and precise tip to finish the object.
The FABtotum Milling Head is a 200W brushless motor able to carve, engrave, cut, mill different materials like woods, light metal and non-metal alloys, as well as prototyping foams such as urethane.
With speeds up to 15’000 RPM it can also do engraving on PCBs, enabling a whole new word of embedded rapid prototyping with your FABtotum Personal Fabricator.
Why using a 3D CNC machine? What is it used for?
A 3D CNC milling machine is useful to create 2D and 3D objects with high precision. This kind of device is used in big sizes for industrial mass production. A smaller version, like the FABtotum’s is perfect to fit the gap between big and small companies. This tool is perfect when the need of rapid prototyping with a different material arises. While 3D printing can rarely (as for today) create something different from plastic, a milling tool can cut off or engrave many materials such as cardboard, foams, woods, metals or even PCBs. The result will be of an higher precision compared to additive manufacturing and the surface will be smooth.
A CNC machine on a desktop can be of great help for many areas of interest: from architecture to design, from dental and medical to toys and customization.
Modeling foams can be of many kind (see “Accessories”) and can provide great results for scaled landscapes and human body parts; woods and metals might help when reproducing buildings, tools, plates and toys. Milling PCB without using chemicals is just a quicker and safer way to develop new projects. If you wish to know more about different choices, read the dedicated Materials page.
The hardest part is choosing the right bit. There are thousands of choices.
How to choose the best milling bit?
The Milling Head uses standard ER8 collets and 1/8th inch bits (3.175 mm).
You may choose the best milling bit depending on the final goal and the material used.
The ones that can be used on a FABtotum are “end mills”, as they must be used with the provided ER-8 chuck. Among this cateogry, a wide range of possibility is still available to better choose the right tool.
Flat End Milling Bit
These ones are very flexible and can be used for many materials, even the hard ones. They are used to carve the material and take the most of it away without a second step. There are single or double fluted bits (actually, there are milling bits with up to eight flutes): the more you have the hardest can be the material. You wouldn’t use a single fluted for metals.
The number of flutes increase with the hardness of the material. The FABtotum is able to work on any surface but it might be better to add another pass on the same route rather than going too strong.
Ball End Milling Bit
The Ball End Mill, also known as Ball Nose milling bits, are the best option if the shape is not squared but has curves rounded angles. These are the ones needed to mill details or parts that require a nice and smooth finish.
They work perfectly with all surfaces but are likely to be chosen when a soft wood, balsa or foam is used.
The presence of more flutes can add speed and precision, depending on how they spin: moving clockwise the flutes should take off more material while going backwards they would add a cleaner finish to the object.
V Carve Milling Bit
These ones are very flexible and can be used for many materials, even the hard ones. They are used to carve the material and take the most of it away without a second step. There are single or double fluted bits: the more you have the hardest can be the material. You wouldn’t use a single fluted for metals.
The number of flutes increase with the hardness of the material. The FABtotum is able to work on any surface but it might be better to add another pass on the same route rather than going too strong.
