It basically consists of two carriages for the horizontal translations and two towers for the vertical translations. I’ve built two prior CNC foam cutters (not using this kit), and therefore the main challenges with those DIY designs were uneven sliding friction and wobble. These problems are mostly solved during this kit by using plastic bearing sleeves for friction reduction and two linear shafts per axis to scale back wobble. However, it became clear later that the wobble is primarily thanks to lack of straightness within the acme lead screws are. Any small bends within the screws will producing a rocking motion of the carriages, which can show up as ripples within the foam edges.
The stepper motors are 6-wire NEMA 23 motors with 2A drive current. the driving force board was built from a kit by Hobbycnc (Model #4AUPCWHC). This board includes PWM control of the cutting wire temperature . The control signals are sent via a parallel interface connector. The motors need a hefty power supply (up to 8A max), and therefore the hot wire (30-gauge NiCr) also needs a separate power supply.
Most computers nowadays don't accompany a parallel interface. Although there are USB-to-Parallel converters, they're going to not work for CNC control because it's impossible to deliver accurate timing signals through the USB port. the answer is to urge the UC100 CNC motion controller. it's like a standard USB-to-parallel converter, but it's not. it's embedded circuitry and software drivers to supply the precise signals required for CNC motion control. this enables any laptop with a USB port to be wont to drive the CNC. The UC100 is best used with the Mach3 software, which is one among the foremost widely used CNC software. However, it's a generic CNC software, so some customization (known as “screens”) is important. The screens for foam cutting setups are often found in many online forums.
The moving hot wire melts the froth by convective and radiative heat transfer. Therefore, the width of the cut are going to be larger than the wire diameter. this is often referred to as Kerf, and must be compensated within the design. Kerf may be a function of wire diameter, wire temperature, cutting speed and foam type. the simplest thanks to determine wire temperature is by using an ammeter to live the present through the wire. For a given foam type and foam thickness, the present is directly associated with the present. rarity foam will cut easily and can produce a bigger kerf. Slower cut speed will end in a bigger kerf. Therefore, the optimum cut speed and temperature has got to be determined for every foam type. The thickness of the froth also matters. A thicker foam will draw more heat away the wire, and can require a better current to take care of an equivalent temperature.