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Here in our lab, we have ShopBot Alpha, which is The ShopBot router is a low-cost, CNC-controlled router that functions as a workshop robot's workhorse.
It is operated by a typical personal computer and is capable of precise, large-format cutting, drilling, machining, and shaping in a variety of materials.
ShopBot provides new avenues for creativity as well as new methods to be productive.
With ShopBot, you can make a single object or experiment with several designs, patterns, forms, and reproduction techniques in ways that would be challenging to do by hand. By precisely moving the cutter through material, a ShopBot CNC tool can create virtually any pattern or shape and will do it in materials such as wood, ply boards, veneers, aluminum and many composites. A ShopBot CNC can cut material in the same way you would with a saw. |
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Some of the features :
Before going to start the design, be sure to leave at least an inch (2-3cm) around the perimeter of the material. You need to be very careful that, you need to screw the material to the bed of the ShopBot and you do not want the cutter to hit the screws. The free space between the pieces will depend on the diameter of the cutter you use as well.
Differeence between 2D, 2.5D & 3D in CNC
Some CNC machines only moved their Z axis while their X and Y axes were stationary or had a single up and down position.
As a result, the first CNCs were known as 2D or 2.5D tools and were incapable of 3D carving.
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2D CNC |
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When you cut out a part in two dimensions (2D), the features are all cut out at the same depth.
This is typical for engraving, hot-wire, water jet, plasma, and laser cutting.
The DXF Import function of the FlashCut CNC software automates the production of a tool path from a 2D DXF file. Two-dimensional CNC works as the name implies: the toolhead remains at the same depth during the entire milling process with no vertical movement and similarly, 2D contouring is generally used for cutting and engraving. |
| 2.5D CNC |
2.5D machine, also called a two-and-a-half-axis mill, possesses the capability to translate in all three axes but can perform the cutting operation only in two of the three axes at a time due to hardware or software limitations, or a machine that has a solenoid instead of a true, linear Z axis. With 2.5D CNC, things become a little more complex. Here, the toolhead moves across the xy-plane in layers. That is, it cuts into the workpiece at a specific height, and when done with the layer, the toolhead moves a discrete step axially along the z-axis in order to start with the next layer. As such, a 2.5D CNC machine does not need a true z-axis but can do with a solenoid for discrete steps. The limitation is that all features of the workpiece come out flat at varying depths. Note that instead of the z-axis, one of the other axes can also be separated to have the toolhead move in layers along one direction of the table bed instead of vertically. |
| 3D CNC |
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2D and 2.5D geometry is commonly machined using 3-axis machines.
All six sides of a product can be machined using three axes, but this requires a new fixturing setup for each side, which could be costly (more on that below).
One side of the part can only be machined for a single fixture setup.
Most CNC machines are three-dimensional cutters. That is, the toolhead can move along the x, y, and z axes simultaneously to permit double-curved surfaces.
Usually the cutter moves in a back and forth motion horizontally, known as rastering, with concurrent up and down action on the z-axis. Because three-dimensionality is mostly limited to the top surface of a workpiece, it is also known as relief machining.
The added form complexity of 3D CNC machining is reflected in more complicated software programming and G-code files to store multi-axis continuous toolpaths. |
Differeent Types of End Mills |
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A wide range of tool types and configurations are available for CNC milling machines.
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Flat nose mills are used for milling 2D contours and pockets. Ball nose mills are used for 3D milling. Bull nose end mills have a radius corner. They are used to create a fillet on the bottom of a wall. Because they are sturdier than an end mill they are also sometimes used for roughing operations. Chamfer mills have an angled nose used to create a chamfer or to de-burr parts. |
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(+91) 943 407 1193
nihar.mohanty@stpi.in
