CNC Router: Difference between revisions

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The CNC Mill is based on the C BEAM profile from open builds, it is currently a X/Y table type "C BEAM MACHINE" thats 400x400x120mm but we have all the parts to make it a 1000x750mm gantry style ASAP.
The CNC Mill is based on the C BEAM profile from open builds, it is currently a X/Y table type "C BEAM MACHINE" thats 400x400x120mm but we have all the parts to make it a 1000x750mm gantry style ASAP.


To use the machine you have to be '''inducted''', and before then you should be familar with CNC Mills (check the [[CNC Mill Guide]]; it is also a numerically controlled power tool with a '''variable Z''' and so considerable care should be taken in preparation and operation.
To use the machine you have to be '''inducted''', and before then you should be familar with CNC Mills (read the [[CNC Mill Guide]]); it is also a numerically controlled power tool with a '''variable Z''' and so considerable care should be taken in preparation and operation.


Please see the [[CNC_Mill/Feeds_and_Speeds]] page for information on the kind of cut settings you can use on the mill when setting up your CAM.
Please see the [[CNC_Mill/Feeds_and_Speeds]] page for information on the kind of cut settings you can use on the mill when setting up your CAM.

Revision as of 14:42, 6 December 2016

The CNC mill.
The CNC mill without spindle. CNC Mill.

Description

We currently have a under construction C BEAM based CNC Mill. The mill took its first cut on 20/02/2016.

The CNC Mill is based on the C BEAM profile from open builds, it is currently a X/Y table type "C BEAM MACHINE" thats 400x400x120mm but we have all the parts to make it a 1000x750mm gantry style ASAP.

To use the machine you have to be inducted, and before then you should be familar with CNC Mills (read the CNC Mill Guide); it is also a numerically controlled power tool with a variable Z and so considerable care should be taken in preparation and operation.

Please see the CNC_Mill/Feeds_and_Speeds page for information on the kind of cut settings you can use on the mill when setting up your CAM.

Once you have a valid Gcode file from your CAM package, you will be able to use http://chilipeppr.com/grbl whilst at the space to run your file on the CNC.

Specifications

  • 800W water cooled spindle 220V 6.5A with ER11 collet
  • 1.5kw VFD capable of 3000-23000 rpm
  • 3.2Mn NEMA 23 steppers
  • 36V Stepper power supply
  • 2.5A Stepper drivers
  • Control via GRBL running on a arduino screw terminal sheild
  • Raspberry PI serial to JSON server making the CNC shield available on chillipeppr.com when at the space.
  • 325x250x100mm workspace
  • No load max feed of 5000mm/min
  • 6 x Capacitance 6-36V end stops

Configuration

Here is the basic configuration of the machine to judge it against others you may see.

GRBL

The CNC uses G code parsed by GRBL. Send the command $$ to GRBL to read the current configuration. This should not be changed unless something significant changes with the machine.

  • Homing is enabled
  • Hard limits are disabled
  • Soft limits are disabled

VFD

The spindle is controlled by a VFD. The current configuration settings can be found on the VFD page.

Drivers / Motors

Drivers are TB6600's 'capable' of 50V 5A

  • 1/4 microstep mode
  • Full power
  • Supplied with 36V

Motors are 3.1Nm Nema 23

Build notes

The end stops are wired as follows:

1 - Positive 2 - Gnd 3 - Signal 4 - Signal

Experimentation is required to determine which detector

Pledges

A pledge tracker can be found on this google sheet [1]

Design

The first machine is a 'out of the box' C Beam Machine kit [2]. This is a X/Y table machine based on the C Beam aluminum profile which offers better stability and accuracy than OX type v slot or shapeoko.

This kit will be used to make the plates for its own upgrades into our specific 1000mm x 750mm gantry style machine with dual X drive based on this design. [3]


Parts Status

We have purchased the majority of parts from Colin at robocutters.co.uk[4], he offered a wealth of advice, a great discount and is genuinely interested in supporting Hackspaces.

  • A C Beam machine kit
  • 3 NEMA 23 Motors
  • 1 1000mm linear actuator kit
  • 1 750mm linear actuator kit
  • 4 750mm 60 aluminium profiles
  • 16 wheel kits

From China we ordered as a kit:

  • 800W 60mm mount water cooled spindle
  • 1.5kW VFD
  • 12 VPump
  • Various collets

From other sources:

  • 6 C.P type limit switches (swwils)
  • Radiator (swwils)
  • 4 Core spindle cable (swwils)
  • RUMBA Board + Drivers (Martyn)
  • E-stop (Aidan)
  • Arduino CNC sheild (swwils)
  • Arduino UNO (swwils)
  • 36v 10A PSU (Aidan)

Parts needed

  • Cable chains (larger machine)
  • Regular stop / go button

Build log

  • First cut occurred
  • Limit switches installed.
  • Hard limits set
  • Soft limits set (but broken!)
  • Dir inversion issues (0,0 should be lower left?)
  • Dir inversion worked out (its actually correct to set machine into negative space)
  • TB6600 Stepper Drivers Installed
  • Wasteboard installed
  • Some hold downs installed
  • Machine tightened and thread locked (blue)

Upcoming

  • Writing documentation
  • PWM spindle control / enable

Software Proposals

GRBL vs TINYG [5]

CAM [6]