First, I would like to thank Vicious1 for sharing his awesome build with us, the design is very nice and so far it seems to work pretty well.
I’ve started the construction of my MPCNC about one month ago and it is now almost finished and functional. Currently, it is able to do 3D printing and CNC cutting, I plan to add the laser and maybe other stuffs later.
The size is about one square meter, and I should be able to print or mill objects about 70-80 cm height with a few modifications if I ever need it one day.
I intend to use this MPCNC as a 3D printer for big projects, who necessitate to print oversized parts. So, I’ve chosen to use quite a big nozzle for it, with 1.2mm diameter, to be able to print at reasonable speeds.
For now, when I use this machine as a CNC router, I mill objects with a simple dremel tool, but I plan to go for a big 1.5KW brushless motor soon, to be able to mill faster and, hopefully to be able to attack aluminum.
I’ve printed all the parts on my Delta printer, they came out pretty good, thanks to all these drawings being optimized for 3D printing. The only issue I had was that they somehow came out a little too big, so the bearing were too loose on the tubes, I could not get contact of all the bearings at the same time. I’ve slightly bend the parts using a hot air gun to compensate for this play and now everything seems fine.
The printer features endstops on all axis, as well as a custom made automated bed leveling probe, which works using an infrared sensor: basically, the print head crashes into the bed. The head being mounted on a pivot, it will move across the beam of the infrared light, telling the arduino that the head has touched the bed. So no need for any offset, the Arduino knows exactly where the printer is. I’m pretty happy with this system so far, it works really well.
All the steppers motors are wired using RJ45 cables, which I find quite convenient tu use for this application.
The tubes are totally overkill, these are some incredibly tough carbon steel precision tubes: impossible to bend, to drill or even to scratch. I had to use standard tubing for the Z axis since I fas totally unable to drill holes in the tough tubes, even with my drill press and my best drill bits.
I’ve design the table myself, and I think it has some pretty interesting features:
-The bed is adjustable in height for about 40 cm. This allow me either to print tall objects, or to mill big objects. Let’s say you have a little coffee table and you would like to engrave the table top, just low the bed, put your table on it and you can engrave it!
-The MPCNC istelf is adjustable in height for a bit more than 25 cm, which can help in case or any special object too big to fit. I will use this feature only if I have no other choice, since the Higher the CNC is relatively to the table structure, the less rigid it will be.
-The structure will be super strong. I did not glue it or install the reinforcements parts yet, but it will be sturdy as hell once finished due to the 90x90mm wood posts I’ve used for its construction
-I plan to add a downdraft system to secure the workpieces in place. It should be easy with this type of design
The only downside so far is that it is had to build this very precisely So you get everything square. Unless maybe if you have some good tools for woorworking, which I don’t really have. I have quite a bit of work yet to do to make everything square.
Anyway, I could speak about it for hours, but maybe it’s time for some pictures now!
All the 3D printed parts… took a while to get there:
The central carriage
I had too much play in the central section, So I chose to put heat shrink on the tubes. I’ll see how long it will last
The bed autoleveling support
If the little screw gets in the path of the IR beam, it opens the circuit
First print test: not great but not too bad given the test conditions
Another calibration test. It’s incredibly fast with a 1.2mm nozzle, less than one hour to print this… It would take at least 3 with the delta, which is not exactly a slow printer!
Time to design the table
The bed can be moved up or down
The MPCNC can be moved too
Time for woodworking now
I’ve used the mortise and tenon technique, for maximum rigidity
Installing the MPCNC on it
Some enclosures to protect the electronics
Testing it as a CNC
I’ve got very decent results, aside from one mistake I made (I didn’t tighten the dremel bit enough, so it got loose at some point)
A new 3D printer head that I will try soon. With that much cooling it should work great!
Now the next steps are:
-Glue the structure together
-Apply a nice finishing
-Put it on wheels
-Install a “real” router motor (if compatible with my bank account, a big brushless)
-Calibrate the printer and CNC correctly
-Try the laser capabilities
-lots of other long term improvements…
Hope you enjoyed this presentation, see you !