Brushless DC Motor Used For High Speed CNC Spindle

Brushless DC Motor CNC Spindle

Brushless DC motors are common place in RC Vehicles. They are small, light, fast and can be inexpensive. [Raynerd] wanted a new spindle for his CNC machine and thought that a brushless DC motor would be a great platform to build from.

[Raynerd] started with an off the shelf motor that had an 8mm shaft. This shaft size was important because the motor shaft was to be replaced with an ER16 collet arbor of the same size. A collet is a device used to hold cutting tools by collapsing a segmented ring around the tool. Collets allows for quick tool changes while providing a strong clamping force. ER16 is a designation of one of many collet standards.

The main housing was machined out of aluminum specifically for this project. This housing holds two radial load ball bearings that support the new rotating collet arbor. There’s another bearing in this assembly, a thrust washer this time, that keeps the arbor from moving axially in the housing.

The 12 volt output of a standard ATX power supply was used to power the system for testing purposes. A general RC Vehicle electronic speed control and a servo tester work in conjunction to manually regulate the spindle speed. Check out the bench test video and an exploded photo after the break.

[Read more...]

Fischertechnik CNC Machine Looks Innocent Whilst Cutting Your Face

FischerTechnik + Arduino CNC Milling Machine

Hallo iedereen! All the way from the Netherlands comes this fairly unique CNC milling machine built by a handful of Mechanical Engineering students over at the Delft University of Technology. These guys only had one week to build the mill in order to fulfill a requirement of their Mechtronics class. Unfortunately, directly after showing the machine worked, it had to be disassembled.

If the frame looks a little toy-ish, it’s because it is. This particular system is called Fischertechnik and the main support beams are similar to that of aluminum extrusion (ex 80/20, Misumi) except that it is made from nylon. Notice the extremely long cutting bit and comparatively abnormal large Z axis travel capability. What this system lacks in rigidity is made up by being able to carve a very 3D shape with steep sides without the machine hitting the work piece. The loss of rigidity was totally acceptable since the team was only planning on cutting foam and the project’s purpose was to learn mechanics and automation.

[Read more...]

Milling Curved Objects With A G-Code Ripper

HaD Mouse

Milling and routing flat surfaces is pretty much the point of a CNC router, but how about curved surfaces? Auto leveling of hobby CNC machines and 3D printers is becoming commonplace, but Scorch Works is doing just the opposite: using a probe touch probe on a CNC machine to transform a G-Code file into something that can be milled on a curved surface.

The technique is pretty much the complete opposite of Autoleveller, the tool of choice for milling and routing objects that aren’t completely flat or perpendicular to the bed with a MACH3 or LinuxCNC machine. In this case, a touch probe attached to the router scans a curved part, applies bilinear interpolation to a G-Code file, and then starts machining.

The probe can be used on just about anything – in the videos below, you can see a perfect engraving in a block of plastic that’s about 30 degrees off perpendicular to the bed, letters carved in a baseball bat, and a guaranteed way to get your project featured on Hackaday.

[Read more...]

Pulse Generator Tells Your Motors “Get Ta Steppin”

Stepper Motor Pulse Generator

Stepper motors are great for a bunch of projects; CNC machines, clocks or robots for example. Sometimes when working on a project that does include a stepper motor and driver, it would be nice to test that part of the build without hooking everything up. A pulse generator could be used to complete such a task and [CuteMinds] has put together a DIY friendly version tailored specifically for stepper motors. This device makes quick and easy work for testing out those stepper motors.

At the heart of the pulse generator is a 12F675 microchip which looks to the resistance value of a potentiometer to adjust the square wave step signal output from 20hz to 3khz. Just having the step signal would pretty cool but this project goes a little farther. There are 3 sets of headers on the board that allow you to connect either a jumper or switch in order to: 1) turn the power on, 2) enable the stepper driver and 3) select the direction the motor turns. The on-board batteries make this unit portable for remote usage.

If you are itching to make one for yourself, the Eagle schematic and board files are available for download at the above link.

$400 DIY CNC Machine is Surprisingly Simple!

drawer slide cnc

Once you go CNC you never go back — they’re just too darn convenient! [Drez20001] shows us how he made one for around $400. Who needs expensive roller bearings when you can use drawer slides?

That’s right — the majority of the cost of this CNC machine are the things you can’t really get any cheaper — the servos (or steppers), the belts (or leadscrews), and of course the motor controller plus computer interface. Everything else? Plywood, drawer slides, and a bunch of fasteners can be had for next to nothing!

He had wanted to build a CNC for years but was mostly hesitant in doing so due to the cost and apparent complexity of the build, but when he started to look into it seriously, he found it really wasn’t the case! It’s built on the basic gantry system design where the X-axis drives a bridge containing both the Y and Z-axis. It’s not a heavy duty machine by any means (he just has a small dremel-like tool in it right now), but for his purposes it’s more than enough.

One rather creative way he saved a few dollars is with his motor couplers — he’s actually taken rubber gas line and cinched it onto both shafts, which he says works quite well!

[Read more...]

CD Drive CNC Machine Steals Matt Groening’s Job, Says ‘Ha Ha’

CD Drive CNC Machine

DIY CNC Machines are fun to build. There are a lot of different designs all over the internet. Some are large and some small. Some are made from new material and others from recycled parts. [Leonardo's] newest project is at the absolute far end of the small and recycled spectra. His CNC Machine is made from CD Drives and can draw a mean Nelson.

First, the CD Drives were disassembled to gain access to the carriages. These were then mounted to a quick and dirty wooden frame. Notice the Y Axis carriage is mounted with bolts and nuts that allow for leveling of the bed, not a bad idea. A Bic pen mounted to the Z axis carriage is responsible for the drawing duties.

[Leonardo] does something a little different for generating his g-code. First he takes a bitmap image and converts it to monochrome using MS Paint. The image is then imported into Cadsoft Eagle and using a modified import_bmp.ulp script. The bitmap is converted into what Eagle considers wire traces and then outputted as x and y coordinates for each wire complete with a command for lifting and lowering the pen.

A PC sends the move commands via USB, through a PL2303HX USB-Serial TTL Converter, to a PIC16F628A which, in turn, sends step and direction signals to the three Easy Driver stepper motor drivers. The stepper motor drivers are connected directly to the original CD Drive motors.

Check out the video after the break….

[Read more...]

DIY 3D Tilt Sensor

tilt If you’re trying to detect the orientation of an object, sometimes you really don’t need a 6DOF gyro and accelerometer. Hell, if you only need to detect if an object is tilted, you can get a simple “ball in a tube” tilt sensor for pennies. [tamberg] liked this idea, but he required a tilt sensor that works in the X, Y, and Z axes. Expanding on the ‘ball in a tube’ construction of simple tilt sensors, he designed a laser cut 3D tilt sensor that does all the work of of a $30 IMU.

The basic design of this tilt sensor is pretty simple – just an octahedron with four nails serving as switch contacts at each vertex. An aluminum ball knocks around inside this contraption, closing the nail head switches depending on what orientation it’s in. Simple, and the three dimensional version of a ball in tube tilt sensor.

To get the tilt data to the outside world, [tamberg] is using an Adafruit Bluetooth module, with two of the nails in each corner connected to a pin. With just a little bit of code, this 3D tilt sensor becomes a six-way switch to control an RGB LED. Video of that below.

[Read more...]

Follow

Get every new post delivered to your Inbox.

Join 96,712 other followers