CNC Micro Mill

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This tool cannot be operated without completing a training course.

Documentation

Commissioning notes:

CNC Mill original condition 20220116 122715.jpg

  • All slide-ways, leadscrews and oiling points oiled with ISO68 Slideway lubricant.

Issues to be resolved:

Electrical

  • Entire electronics assembly need enclosing
    • Started work on new enclosure. All electronics removed from MDF back panel and in process of being installed in a 19" rack case.
  • Cable management
    • New steel wire braided flexible control cable acquired
    • 3d printed enclosures for stepper motor drive cables design. Awaiting test prints. Will use 19.5 x 19.5 x 1.5 aluminium U channel to protect cables
    • 3d printed covers for stepper drive unions designed and some printed. Stepped cover needed a redesign. New cover design to accommodate a cable gland to accept the new control cables designed and awaiting test prints
    • All limit switches and stepper cables are unconstrained and unprotected from snagging, - This is now in hand
    • A selection of sealed proximity switches have been ordered which will, hopefully, replace the microswitches currently in use.
    • 7i76 breakout board enclosure needs a lid - box to be replaced by mounting board on rail inside new enclosure. Mounting brackets are part of the parts we were given with the mill. An ally plate has been marked up but needs cutting to size, drilling and tapping
    • Common-ing block needs mounting. Has been addressed using parts which came with the kit
    • Parallel cable management. Originally the 25 way parallel interface cable was connected directly to the control board. This would place undue stresses on the board. 25 way IDC D-con parts have been acquired to make up a cable to go from the control board to a bulkhead mount socket.
  • Motor power
    • add a 13 amp socket to the back of the case and a relay so that the motor can be controlled from the controller

Control Issues

  • A touch off probe needs making
  • A jog wheel / pendant would be handy

Safety Issues

  • Additional Kill Switches
  • Full Safety Enclosure with cut-out interlocks on any doors
    • new enclosure to be designed in machine building system ally strut with polycarbonate panels to protect users
    • interlocks to be added to any opening panels
    • need a good solid baseplate. Ideally something like ally tooling plate. How big should it be?
    • what is the operational footprint / volume of the mill? How big should the enclosure be?

Trainers

Mark Mellors

Trained Users

Technical Specs

Machine Model
Axminster White Micro Mill Model Number 010061 (Circa 2004)
Equivalents (More modern versions)
Axminster Super Micro Mill SX1 Model Number 505098
Axminster Super Micro Mill Sieg X1 Mk 2 Model Number 600881
Mill Spindle Motor
240V 150W
Electronics Power supply
MeanWell SP-500-27, 500w, set at 24V
Speed Range
Electronic Motor Speed Control
Low Ratio Gearbox Speed Range 100 - 1000 RPM
High Ratio Gearbox Speed Range 100 - 2000 RPM
Spindle Motor Direction controlled by Forward/Off/Reverse Manual Switch
Column Dimensions
65x56mm
Throat
140mm
Nose of Spindle to Bed (max)
255mm
Nose of Chuck to Bed
min: 5mm, max: 175mm
Manual Quill Travel
Disabled
Spindle Morse Taper
MT2
Draw Bar Thread
10mm
Tool Capacity
Max Drill Capacity (Max Drill diameter)
10mm
Max End Mill Capacity (Max End Mill diameter)
10mm
Max Face Mill Capacity (Max Face Mill diameter)
20mm
Head Tilt
45 - 0 - 45 degrees either side of vertical for whole head column
Bed Size
X 240mm x Y 145mm
Bed Slots
3 x 8mm T-Slots
X Axis Travel
200mmm
Y Axis Travel
180mmm
Z Axis Travel
170mmm (Software limits), 255mm (mechanical limit)
Overall machine envelope
L 490mm x W 430mm x H 700mm
Weight (base machine without stepper motors)
32kg
Stepper drivers
TB6600† * 4 (4 axis capable setup)
†assumed, matches outwards appearance but part number not visible
Stepper motors
AC570764525M (NEMA 23 size) on X, Y & Z. no fourth axis stepper fitted
Interface card
MESA 7I76 (on mill backboard) connected to a MESA 5I25 (uppercase i in both board numbers)
2022-01-13 13.19.15.jpg
Notes
There's a probe input wired in to a 3.5mm headphone jack on the head of the mill.
The spindle speed/on/off is not CNC controlled
Manual control panel
Electronic Motor Speed Control
Low Ratio Gearbox Speed Range 100 - 1000 RPM
High Ratio Gearbox Speed Range 100 - 2000 RPM
Spindle Motor Direction controlled by Forward/Off/Reverse Manual Switch
2022-01-13 13.24.36.jpg

The spindle speed needs to be ramped up from zero speed. If the direction is enabled with a non-zero speed, the "UNNORMAL" indicator will light and the spindle won't start.

The motor control has a fault LED marked "UNNORMAL" if this lights stop the machine immediately remove all power and seek assistance!

Software:

Linux CNC

2022-01-13 14.01.14.jpg

LinuxCNC Homepage
http://linuxcnc.org/
Software package download http://linuxcnc.org/downloads/
Documentation (latest version, not necessarily applicable to the 2.7.9 version installed on the PC)
HTML Online Documentation http://linuxcnc.org/docs/2.8/html/
PDF Documentation http://linuxcnc.org/docs/2.8/pdf

Tool Workflow:

Initial placeholder simplified and skeleton outline workflow

  1. Model part in Mechanical CAD package
  2. Export model as a xxxx format file
  3. Load model file in to CAM (Computer Aided Manufacture) postprocessing tool.
  4. Process solid model into a tool path appropriate for capacity of the micro mill
  5. Export tool path
  6. Import tool path into Linux CNC machine connected to Mill
  7. Check job
  8. Safely mount workpiece on bed and check orientation and parallelism / datums
  9. Install first tool
  10. Run Job
  11. Change tools as required until job is completed.

Examples of what the mill can make

Engraved sign (plywood, v bit) Engraved sign (plywood, v bit)


Accessories:

Mill Accessories
Posilock chuck Set of 8 metric and imperial posilock collets: 6mm, 10mm, 12mm, 16mm, 1/4", 3/8", 1/2" and 5/8"
4 flute coated end mills, 2, 3, 4, 5, 6mm, all 6mm shank Clamp set
C spanners Rotary Table
Small toolmakers clamp Small machinist's vice
Spare/alternative 5125 MESA card 2022-01-12 22.15.08.jpg