Full instruction with photos are at:
Here is the excerpt:
One of the newer open source printers that is gaining a popular reputation for being a well built printer that just plain works is the printers from Lulzbot. We got our Lulzbot mini about three months ago and it prints perfectly on every print running production every day non-stop! Needless to say, we love our Lulzbot, but it is missing something… A Laser! You can’t have a 3D printer without a laser! Come on now.
Here we outline the instructions for upgrading the Lulzbot mini, but the Taz is just the same. It has the same extruder and electronics, the platform is just a bit larger. If you want to see how to build a laser only system, check out our blog post here.
So here it is – Instructions on how to upgrade the Lulzbot printers. Let’s start!
We are going to use the fan1 connection on the Rambo board to control the laser. It has PWM control needed to do picture engraving and is easily controlled with M106/107 commands in software. We decided to mount the laser in front of the extruder so you can print then laser without any changes. We choose to mount the driver on the side of the printer because there was already a hole for the driver to attach to and the existing cables in the laser upgrade kit will reach it. We routed the laser and fan cables up the wiring harness chain to the Z axis and made it all nice and tidy with zip ties. You can cut the fan cable and either splice the wires to the laser driver intput H2 or maybe even put a nice little switch in to change between laser and printing.
We designed a nice little mount for the laser to attach to in front of the extruder. The good news is it just needs one additional screw! Get a small M3 screw and it will mount to the existing little hole in the aluminum plate on the extruder mount. Take the other screw from the left of the assembly off and put it through the new mount.
To protect the build plate we put some plastic with a sheet of aluminum on top of it and taped it in place. You can use whatever material you want for a sacrificial material and tape it or secure it somehow to the platform.
We had to modify the firmware of the Lulzbot because the PWM frequency was set way to high for it to control the laser. You can get the firmware from Lulzbot here:
or for the TAZ printer it is in the software folder here:
You need to load all of the files into your Arduino compiler and make a new sketch that shows all of the files. Make sure you have the newest version of the compiler downloaded from Arduino HERE. Set you board as Arduino Mega or Mega 2560 . Then in config.h, comment out the line:
Then make sure your are connected to the correct COM port and the printer is connected to the computer and compile the firmware. You are now done!
We used Repetier Host to control the printer. We like the “preview” feature for the G Code and it does a good job with everything else as well. You need to adjust some of the settings because the table will be slightly smaller. Here are instructions for the configuration:
Ok, now let’s get to the upgrading with pictures!
Step 0 – Print out the mount
The mount has been designed to sit right in front of the extruder assembly and also allow for the fan upgrade to be mounted as well.
Step 1. Remove the left screw on the extruder assembly.
Step 2 – Attach Laser to mount
Step 3 – Prepare screws to attach to printer
Step 4 – Place mount in front of extruder and screw in.
Step 5 – Route cables to the back cable chain.
Step 6 – Zip tie cables to chain.
Step 7 – Put laser driver on front side of printer.
Step 8 – Use existing hole to mount the laser driver.
Step 9 – Change out the driver nuts to make spacer to hold driver when you screw it in.
Step 10 – Open electronics to get to the fan cable.
Step 11 – Cut fan 1 cable and splice in cable for laser driver.
Step 12 – Open the Arduino SW and load the Marlin firmware (either Mini or Taz). In config.h, comment out the line FAST_PWM_FAN like in the picture. You can also use SW PWM, but make sure it is not above 5KHz.
DONE! READY for LASER!!!