To understand what i am building please take a look into the presentation of the ANT PCB Maker.
I started building the original machine shortly after the release of the project as i like CNC machines and always wanted to make some small PCBs for some projects. For this first build the only changes i made was using Nema 17 instead of Nema 11 for X/Y Axis and later on i designed a custom electronics enclosure and added a cable chain.
The main things i wanted to be improved for my bigger build where the following:
- A bigger working area as i want to create PCBs for keyboard style input devices.
- A better motor for the z axis. The one in the first version was way under powered and the current build of the Ant comes with a better solution (but still close to its limits).
- A better modularity of the CNC head to exchange with different tools.
- A less noisy spindle motor as i live for rent and don't want to anger my neighbors.
- Wood and possibly even metal engraving? Who knows...
I made some calculations on paper and came up with an aluminium profile length of 320mm for X and Y.
This way i wanted to achieve a working area that could work with 150x200mm PCBs. I also switched from the 10mm Makerbeam profiles to 20mm profiles.
In the next step i designed electronics enclosure, Nema 17 mounts for X/Y and added linear rails to my design.
The electronics enclosure was designed more closed than the original design to protect from dust. In the current state the top is open as i still have to design a mount for a cable chain. I have 2 connections for external power supplies so i could separate the power for spindle motor and the stepper motor electronics.
The second step was designing the Y carriers with X axis and the belt mounts on the front corners. I have chose 10mm rods instead of the 6mm rods for the X axis. The mounts for redirecting the belts with pulleys are designed more robust than the original ones.
The most complicated construction was the wagon mounted on the X axis. The design is close to the the original design except for the Z motor. All the mountings for the bearing were designed in a way that replacing/removing them is pretty easy. So if i want to make updates to the design i can remove them without using raw force.
I installed 4 end stops for X and Z and modeled cable canals inside the print to hide the cables.
As i want a bigger motor and more flexibility in changing tools i went the classic CNC way and mounted the motor on top with its threaded rod between the Z axis rods (6mm).
In case you miss the threaded rod in this picture. Like some other parts i just couldn't find correct models - so it only exists 'in my head'.
This construction also has mounts for a short cable chain on the left to hold the cables to the spindle motor.
The last step (so far) was adding an experimental mount for a Proxxon Micromot 50/E (Amazon) that i already have and that is super silent in hand operation.
Unfortunately the Micromot does not stay quiet when put into the mount. The machine acts as an resonance body and the noise at 20k rpm gets pretty close to the original ANT. While achieving a tiny bit less noise at much higher speed the downside is that the spindle is farther away from the X axis than it would be possible with a configuration like in the ANT.
What exactly causes the resonances is hard to tell. Using thicker rods than 6mm might help or printing with more infill instead of the 60% i used. But since reprinting or even redesigning would take a lot of time i probably won't have the answer soon.
The next things i have to do are:
- Add end stops for the Y axis.
- Create create cable chain mount on electronics enclosure and on head.
- Create a mount for MDF board and put PCB mounts on it.
- Find a final solution for a spindle motor with less noise.
