Sunday, December 28, 2014

Cheap Chinese Laser Engraver/Cutter Upgraded with Smoothieware Running on Azteeg X5 mini board

Unboxing.  This laser cutter cost about $480 and was shipped from a US warehouse. It arrived quickly and undamaged.

My K40 probably has the cheapest laser tube mounts available. Note the high precision Chinese newspaper used for tube alignment!

Initial conversion was based on Dan Beaven's excellent RAMPS 1.4 upgrade buildlog.

I was having issues with Marlin, due to EMI from the horrible wiring of the K40 I now suspect.  So I decided to give Smoothie a try since I had an Azteeg X5 mini enroute...

First thing to do was to rewire the K40. The original wiring was just atrocious. The wires from the mains input were woefully under sized and, inexplicably, a 30-inch run to the power switch was spliced together (poorly.)

The connectors were all crap.  The ballast resistor for the tube had solder applied to the the terminals just to get the connectors to (sort of) fit, but it was still arcing.  The wires for the mains input were soldered on, but when I took them apart it turned out the solder on the ground was broken, it was just held on with heat shrink tubing! I replaced all the AC wiring and connectors, because I kind of like living...  Mains voltage *might* not kill you, however, the 40K volts from the laser PSU surely will and having the grounding right is super important.

Next, took out the X-Y platform to do some modifications.

Replaced the big inductive endstops with nice compact mechanical ones, which added about an inch in cut area for both X and Y.  Also added drag chain for the wiring, using the original sheet metal to fabricate mounts.

Replaced the X stepper and drive gear, also added an Astrosyn vibration damper while I was at it...

I rigged up a wiring harness to connect a RepRapDiscount Full Graphic LCD to the Azteeg X5 mini.  

Picked up some 3/4" standoffs to provide adequate airflow for the stepper drivers and repositioned the mounting plate to make the USB and microSD card on the Azteeg accessible through the existing slot on the K40.

Getting my wiring sheathed and preparing to install the board.

The Azteeg X5 mini is in place.  Using a logic level shifter to interface my (5v logic) laser PSU to the the (3.3v logic) Azteeg.  Still need to print up a mount for the level shifter board.

Got the X-Y assembly back in and aligned the optics.  Currently using some magnets and nails as a pin table for cutting.  Working on a proper Z-table.

First cut using Smoothieware was the panel for the controls.  Spacing was a bit tight, but it's functional.  I replaced the crappy original ammeter with a vintage Westinghouse meter I picked up on eBay as part of a lot of 40, it's most excellent (and older than me!) I need to cut the sheet metal and make a new panel at some point, but, for now, I'm quite pleased.

The second part I cut was a panel to accept the 4" duct from my 13 Gallon Harbor Freight Dust Collector.  

Also, found I needed to rotate the laser tube such that the water jacket wouldn't trap air bubbles. 

Lastly, I added a strip of LEDs to light up the table...

[This buildlog is a work in progress.  Any criticism is greatly appreciated!]

Special thanks to:

Dan Beaven
Lansing Makers Network (especially Tim Schmidt)
Smoothie (Thanks Arthur, Mark and Jim!)

Couldn't have made this thing work without them!