grbl controller error:undefined feed rate

Grbl Controller Error:Undefined Feed Rate Download Step 1

The design is parametric in the sense that we can define the lengths and widths of the machine and the design would accommodate accordingly.

A Tinker and a Maker, taking things apart and putting them back in a better way.

It allows the ability to cut out any aerofoil shape from a CAD design accurately.

A properly configured machine can save you a lot of effort and produce a smooth finish.

The machine has a Nichrome wire stretched between two towers.

The 2D CAD design to be cut out is turned into G-code and fed to the machine, which moves in four independent axes to create complex contours like tapered wings.

The motion of each axis can be achieved by any means such as linear bearings on smooth rods or by using drawer slides of various sizes.

Each axis is driven by a stepper motor through a Leadscrew, a GT2 belt and pulley can also be used depending on the size of the machine.

The cutting forces involved is minimal and the construction only needs to be rigid enough to withstand the tension of the wire stretched between the towers.

This is a true 4-axis machine capable of cutting different shapes on both sides simultaneously, the problem then becomes, how to control 4 independent axes at the same time.

Many tutorials focus on 3-axis machines like 3D printers but there does not seem to be enough documentation on building a 4-axis machine using easily available parts and open source software.

We found a few people who had done similar projects using Arduino and Grbl and decided to make a CNC hot wire cutter of our own.

Grbl Controller Error:Undefined Feed Rate Download Step 1

The build log and documentation can be found on Github Add Tip Ask Question Comment Download Step 1: Hardware Depending on the design you choose to make you can substitute parts with the ones you find locally.

For example, you can switch the steel tubessmooth rods with a Drawer slider, which can act as a linear axis.

Plywood (12mm) Rails (Steel tubes, Smooth rods) Lead screw (M8 x 600mm, as long as you need the axis to be) M8-M5 Motor coupler (M8 for the Leadscrew and M5 for the motor shaft) Arduino Mega 2560 Ramps 1.4 board Stepper Motors (one for each axis) A4988 Stepper driver (one for each stepper motor) 12V Power Supply for ArduinoRamps Variable power supply (Lipo chargers with Hot-wire mode) Nichrome wire (32-28 gauge, depending on the size of machine) The core components are the Arduino Mega, Ramps 1.4, Stepper drivers and motors.

The rest of the machine can be made with any design and hardware.

Add Tip Ask Question Comment Download Step 2: Software Grbl Hotwire Controller 4-Axis G-code Generator Wing Gcode Jedicut FoamXL The difficult part in making a 4-axis CNC is finding software to generate the G-code and to drive the machine.

There are many people using DevFoam and profilli for generating the G-code and to control their machine.

Our search led to an Arduino based 4-axis G-code interpreter developed by Marginally clever which uses an Arduino Mega 2560 and the Ramps 1.4 CNC shield.

His page has codes for moving 4 independent axes and a Java-based G-code sender that could send the G-code to the Arduino using the serial port.

We got it working after some fiddling, its not the most straightforward method and there is almost no documentation on how to use it.

RcKeith has some good documentation on the machines he built and what he used to control them.

We stumbled on a post in rcgroups.com, It was for a CNC foam cutter using Arduino and GRBL, from there we started building the machine.

Attachments Grbl Hotwire Controller.zip Download GRBL8c2mega2560RAMPS.zip Download FoamXL 7.0.zip Download Add Tip Ask Question Comment Download Step 3: Building the Machine I designed the machine using Autodesk Fusion 360, which has great toolset for parametric CAD and CAM capabilities.