programming / cailbrating the foamcube controller

When you first hook up your arduino-based 5-axis foamcube controller, you may want to adjust some settings like steps-per-millimeter , 3 or 5 axis mode and other choices for first time use. Adjustments are easy ; the controller can be calibrated or programmed in a couple of different ways :

Adjust settings through the LCD display

Most of the basic settings can be adjusted using the rotary encoder knob on your controller. Simply push the controller button , turn to the correct menu-option and press the button again. While this option is fine for basic settings you can also use our direct programming mode for more finesse and control

Adjust settings through a serial monitor

While your controller has an LCD screen, it also communicates through a computer screen with help of a so-called “serial monitor” . While on the serial monitor enter command (type on your keyboard) “M100” and hit enter. This shows you a help screen and explains all your direct programming options. People that have used GRBL and similar controllers may be familiar with this way of programming.

Things you can programm directly :

  • 3 or 5 axis mode
  • default speed setting
  • X-axis steps per unit (millimeters , degrees , apples , parsecs or whatever you prefer )
  • Y-axis steps p/u
  • U-axis steps p/u
  • V-axis steps p/u
  • A-axis steps p/u (on foamcube usually the rotation platform / steps per degree)

Typical direct progamming is done using a combination of a programming code and a value. For instance , to change the steps per mm. on the X-axis (code “$101” ) to 160 steps we enter :  $101 *160

Values are set in whole numbers preceeded by a star symbol ‘*’ .

****** SET UP MENU ******************
to change variables : type ‘$’ and a number, then SPACE then followed by ‘*’ and number”

$100 set steps per mm for the x-axis e.g. $100 *160 || Integers 1-255 only
$101 set steps per mm for the y-axis e.g. $100 *160 || Integers 1-255 only
$102 set steps per mm for the u-axis e.g. $100 *160 || Integers 1-255 only
$103 set steps per mm for the v-axis e.g. $100 *160 || Integers 1-255 only
$104 set steps per mm for the a-axis e.g. $100 *160 || Integers 1-255 only

materials you can cut with the Foam cube hotwire system

CNC Hotwire foamcutting materials

With Foamcube you can process a large variety of  foam products ranging from Simple hardware store grade EPS to very dense and sturdy EPP blocks. Below are some of the materials you can work with. Any material that melts in a temperature range of 50 to 300 Celsius can technically be cut with Foamcube. By adjusting speed or wire temperature* you can tune in to a perfect cut with a narrow kerf and a smooth surface.

 EPS 60  | EPP 50 | XPS

IMG_20160408_103655

 

EPS – expanded polystyrene

EPS foam typically ranges from EPS 60 to ESP 500. EPS 60 is the stuff you buy at the hardware store, it is very cheap and often used for insulation. When EPS-60 is cut it is smooth but still shows some of the open structure. The higher the EPS number, the more condensed and heavy the foam will be. EPS 300 and up are very dense and can be sanded and have some structural abilities. (furniture, floating things, stage props etc.)

EPS-60 typically cuts fast and needs relatively low temperatures to cut (approx. 25 mm/sec @ 220-240 Celsius). Higher numbers mean lower speeds or require higher wire temperatures.

Low grade EPS 60

EPS 100 demo

XPS – extruded polystyrene

xps a.k.a. styrofoam a.k.a. styrodur a.k.a. styrisol is much denser than EPS and has better insulating properties. It can be purchased at local hardware stores and typically has a yellow or blue color. XPS sheets often act as a composite material because the top and bottom of the sheet are more dense than the middle part. Because of this reason it requires a different setting on your Foamcube and it also matters if you cut sheets perpendicular or parallel. XPS cuts a bit slower than EPS and prefers higher temperatures but has a very smooth finish. (approx. 12 mm/sec @ 250-270 Celsius).

styrisol sheets (XPS) give smooth finishes but cut slower

 

IMG_20160408_103743

EPP – Expanded polypropylene

Epp is an eco friendly foam that is typically very dense and has high structural integrity. When cut it makes tough parts that can handle a beating. E.p.p. is a bit harder to come by, but you should be able to find a few suppliers on the internet that are willing to cater. Due to it’s dense and rugged nature EPP cuts slow but it’s well worth the extra time. EPP wants a hot wire so be prepared for a beefy power supply or a short hotwire. (approx. 10 mm/sec @ 270-280 Celsius).

Rugged and dense EPP foam

IMG_20160408_103717

 Foamcube uses a 0.22 mm. hotwire and has a very narrow kerf width.

IMG_20160408_103328

PE – Poly Ethylene Foam

PE Foam is very easy to cut and is ideally suited for inlays, protective casings, molds, furniture, or to build large very lightweight decor pieces in very little time. Polyethylene foam edges are very clean when cut with a foamcutter / hotwire and the material is fairly cheap, comes in dozens of colors and all kinds of sizes.

Dozens more ….

While the materials above are most often used in our lab, there are naturally dozens of other materials you can cut and style with our CNC Foam cutter. Feel free to experiment and play. Foamcube can handle some abuse and loves new stuff to chew on ! Found a new material to play with ? Please let us know …..

a word about NiCr hotwire length for foamcutters

nicrFor Foamcube we use NiCr type hotwires. NiCr stands for Nickel Chromium.

The NiCr wires are strong, can handle high temperatures and do not expand too much when heated. They are also available in very small diameters so the kerf of our foam cuts can be nice and tight.

Since most Foamcube wires are either a maximum of 50 cm. or 100 cm. we use the same wire for both and simply vary the voltage running through the wires. Ideally we want a temperature range of about 220 – 300 Celcius, which can easily be achieved by using either 12 volts or 24 volts.

The wire we use has a resistance of 22 Ohms per meter and has a diameter of only 0.254 mm. It’s right in the sweet spot.

When we apply 12 Volts DC to a 50 cm. long wire, it’s temperature hovers around 250 Celcius. It draws approx 1.1 Amps from your power supply.

When we apply 24 Volts DC to a 100 cm. long wire, it’s temperature hovers around 250 Celcius. It draws approx 1.1 Amps from your power supply.

So by doubling the input voltage you can make the hotwire twice as long keeping the same temperature range. This also implies that by controlling the input voltage you can control the temperature of the hot wire.

When you build your own foam cutter it is recommended to keep your wire length at maximum 40 cm. (12 volts), 90 cm. (24 volts) 190 cm. (48 volts) etc. Power supplies in increments of 12 volts are easy to find and are a lot cheaper than having to acquire say a supply of 28 volts. By keeping the wire length a little shorter you will have a wider temperature range to cut denser type foams using off-the shelf power supplies like ATX supplies from an old computer, LED power supplies from China, or even your typical plug-in-the-wall power supply that delivers more than 1200 milli-amps.

We carry spools of Ni-Cr wire in our online store for your convenience. If you source your wire locally make sure it consists of Nickel and Chromium  (no iron, aluminium and other traces) and has a resistance of 22 Ohms/meter at room temp.

Foam hotel – architectural model

Foamcube comes in many different sizes, but every cube is capable of making models well beyond its boundary size. As an example we used a 1 cubic meter cube to create a 12 cubic meter mockup of a chinese hotel. The hotel was designed and cut by Space and Matter (Amsterdam), read more here : http://fablab013.nl/inspiratie/cnc-foam-cube-cutter-da-lang-palace-china/

The 3D model of the hotel was cut into several smaller pieces and fed into Foamcube. The entire process took about a week to put together, but the actual cutting of all the parts was done in a timespan of approx. 14 hours.

thin foam is cut by standing a sheet straight up
thin foam is cut by standing a sheet straight up
initial body is made out of rough cut blocks
initial body is made out of rough cut blocks
more detail is added
more detail is added
the small details like balcony's windows and columns are no problem for Foamcube
the small details like balcony’s windows and columns are no problem for Foamcube
final pieces were put together using simple white wood-glue and toothpicks
final pieces were put together using simple white wood-glue and toothpicks

 

Below is an image of the model as it was shipped to China. To read more about this project please go to :

http://www.spaceandmatter.nl/dalangfever/

Foamcube safety sheet & quick start guide

Foamcube safety sheet

Foamcube d.i.y. Kits are distributed by :
Bijbibi / Fablab013
Groenstraat 139 Hal 553
5021 LL Tilburg
the Netherlands

via4321@gmail.com
+31 6 373 402 83

online manual : http://foamcuttingcube.com

With Foamcube comes your own personal online drive. It contains important documents, settings, manuals and instructions. Please take time to familiarize yourself with these documents first.


your personal online drive :

https://drive.google.com/open?id=0B08tCnnhDeKgZjkzRnF6cC15Wlk

 

Do it yourself kit & limitations

Please note that all Foam-cube kits are delivered as a collection of loose parts that need to be assembled by the end-user into a usable machine. Although efforts were made to make these products as safe and easy as possible, the distributor can not make any guarantees towards the final product regarding safety or compliance to local rules that may apply in your country or region.

Before you build your machine you should be aware of any regulations that may apply to you when implementing such a machine in a private or (semi)public setting. Note that as the constructor of the machine you take on sole responsibility for safety and compliance and indemnify the distributor against any claims or damages.

 

Potential safety hazards you may encounter

  • Foam cutting machines like Foamcube have electrical parts that may overheat, melt or catch fire. Never leave your machine unattended when it is plugged in.
  • Foamcube uses a hotwire to cut foam. Wire temperatures can run as high a 1000 degrees celsius ! hotwires, when touched, may cause severe and painful 3rd degree burns.
  • Hotwires can easily ignite other sources and start fires.
  • When cutting material with hotwires you may generate noxious or poisonous fumes. Take proper precautions.

 

 

  NEVER connect or disconnect electrical connections when your Foamcube is powered on, plugged into mains, or connected to the USB port.

This WILL destroy the stepper drivers inside your controller.


Welcome to your online drive for Foamcube support. In this google drive folder you will find various documents that will help you get the most out of your Foamcube CNC hotwire foam cutter.

Installing software

As of Jan. 2018 all Foamcubes will be powered by Arduino microprocessors. The software is already pre-loaded onto your arduino controller. To install upgrades or newer versions of the controller software you can use the “XLOADER” software to upload a new “HEX” file into your controller. Both xloader and the HEX files can be found in your online drive in the “software” folder.

HEX files are pre-compiled software packages that can be uploaded to your controller without hassle or difficult settings. Foamcube HEX files all have names with the build-date in them so it’s easy to find newer software for your Foamcube controller.  Name formatting for HEX files : YEAR-MONTH-foamcube…….hex (e.g. 2018-01-foamcube.hex)

 

building your foamcube

If you have not yet started assembly of your cube you can find a standard online assembly manual here : http://foamcuttingcube.com/  Please see the “assembly” menus on the top of the page. Note that your cube may look different so use the guides loosely as Foamcube is always under development to improve user experience.

Need more help ?

While most people have no problems building and running their cube we understand if you have more questions. Please post general questions in our forum and we will do our best to get you an answer within 24 hours : http://foamcuttingcube.com/forum/

Demo files

In your online drive you can find a folder called “demo files”. It contains some .DXF and gcode files to get you started quickly.

Simple 2D  shapes

Flame : load the .dxf file into the usbcnc software and cut it out of a small sheet of foam.

3D shape out of a 2D file

candle 2 : cut it out of a small piece of foam. Then turn 90 degrees and cut it again.

3D shape

candle 1 : cut it out of a sheet that is at minimum 10 cm thick. after it was cut, turn it 90 degrees and load “candle 2”. Now cut candle 2 through candle 1 to get a 3-armed candelabra.

rotationcut

Load bal72.txt as a gcode file. Set rotation platform to 5 degrees. Start the cut and see the bal take shape in 72 cuts. (This is probably the most inefficient way to create a shape like this. Using ping-pong mode in our online gcode builder will be far more efficient.)

online gcode builder – ROTATIONCUTS

Once you are familiar with all the options and settings on your Foamcube you may want to play with our online gcode manipulator a bit. It helps you transform simple 2D outlines into 3D shapes. The gcode it generates can be loaded into usbcnc directly. Don’t be fooled by it’s simplistic appearance. When you put in more complex shapes, you get very complex 3D shapes as results. Experiment !

you can find the online gcode builder at :

http://foamcuttingcube.com/buildgcode/

CNC cut baluster and foam mold

The cube can create complex 3D designs in a very simple manner. This time we want to create a mockup baluster for in the garden, and afterwards we also want to have the pouring mold so we can create new balusters very easy and repeatedly in concrete.

Step 1 : Draw some images in your favorite vector software (we use inkscape , it’s freeware)

baluster

Step 2 : Load your .DXF images into CNC usb and start cutting the foamblocks on your  foamcube.

IMG_20150204_112445

 

Step 3 : rotate your foamblock by 90 degrees and load your second .DXF to make the crosscut

2nd cut to make our baluster
2nd cut to make our baluster

step 4 : remove foamblock and gently extract positive mockup/prototype from your block. What’s left is a perfect mold for pouring concrete or gypsum.

IMG_20150204_120600 IMG_20150204_120611 IMG_20150204_120114 IMG_20150204_120105

IMG_20150204_134640

 

poured in concrete

cnc hotwire foam cutting tips

In order to get the most out of your foam cutting projects we have collected some tips and experiences straight out of the lab :

  • hotwire thickness : thicker wires can carry more current and can get hotter thus travel faster , but with more heat and speed comes more inaccuracy. Keep your wires thin and speeds low for more accurate models.
  • speeds : Denser foams need more heat or lower speeds. Thicker blocks also need a speed adjustment.
  • complex models : To create complex shapes it may be neccesary to rotate your foam blocks in incremental degrees (usually 45 or 90 degrees). Keep your blocks aligned securely and perpendicular to the hotwire for best results.
  • dirt : To cut costs many people use old insulation blocks. No problem, just be careful with any dirt on the blocks that may accumulate on your hotwire. Dirt will instantly bake on and ruin a perfect cut.
  • When you have a choice, always start cutting at the top and work your way down to the bottom of the piece.