I decided to upgrade my Creality CR-10 printer and came across this cool laser head which can easily be added to this printer. There are four small neodymium magnets on the laser head that allow it to be attached to the metal extruder shroud. I wasn't convinced that this is stable enough so I designed a generic tool holder.
This turned out to be much cooler than I expected because I am not only able to place the laser cutter, I can also add a grinder and suddenly I have a tabletop CNC milling machine! You can even change between hot ends so you don't have to unscrew the nozzle if you have multiple hot ends and extra cables/connectors. It is also easier to clean or replace the nozzle because you can hold it in your hand.
The position remains stable if you replace the tool. I tested this with an indicator (DTI) so no need to level your bed after replacing the tool. However, I recommend to add an adjustable Z-stop. I am personally quite fond of this one https://www.thingiverse.com/thing:2757323. This makes nozzle changes much easier.
I have created a Youtube video in which I explain how I came up with this idea and how it is mounted to the 3D printer. Enjoy! https://youtu.be/oK3877cbBeM
Do not use PLA since this is probably not strong and temperature resistant enough. I use a Micro Swiss hot end for printing Nylon and the cooling block stays rather cool. I don't know about stock cooling blocks so check this out before mounting this. I think you can alternatively use ABS or PETG but I haven't tested this.
I was able to use the same nuts and bolts which were already mounted to the gantry because they were just long enough. Because lock nuts are used you must hold them in place with a spanner or similar. This is not possible with the nut at the bottom. Do not place the bolt the other way in (similar to the top bolts) like I did because the nut will collide with the frame. You can use a flat screwdriver to prevent the nut from rotating.
You need a m4×16 bolt, a nut and washer to mount the handle to the base. This is a tight fit intentionally and you probably have to use an 8mm drill to widen the hole of the handle a little.
Beware that the nozzle has an offset in the Y-direction after installing this holder so its homing position is not above the print bed anymore. This can easily be fixed by moving the Y-stop at the back a bit to the front. This comes with the cost of a slightly smaller printing area.
I have added a STEP file of a blank tool holder so you can create one for your own tool. For example, you can create one which holds a pen and let the machine make a drawing.
Feel free to contact me if you have any questions!
Use this thing at your own risk. It works for me, but you are modifying the hot end of a 3D printer. I cannot be held responsible if anything goes wrong and messes up your print, machine or if your house catches fire. Use common sense and always wear proper protection when using a laser head, grinder, drill etc.