My next CNC project - a PrintNC router

[DavidR8]

Is it still a "PrintNC router" or has it morphed into something else?

Still a PrintNC, the core of the design is still exactly as intended, the only shift I made was to go with a commercially available motion control board and software. Everything else is exactly as I planned it and true to the PrintNC design philosophy.

 

[PeterT]

@David_R8 I watched the videos you linked. I don't have a complete comprehension of the CNC mechanics & certainly not the electronics, but I was impressed with various 3DP fixtures & how they integrated the base tube frame build. Look forward to yours as it proceeds to completion. CNC looks like a rabbit hole to oblivion. I dare not stare into the light LOL

 

[DavidR8]

@David_R8 I watched the videos you linked. I don't have a complete comprehension of the CNC mechanics & certainly not the electronics, but I was impressed with various 3DP fixtures & how they integrated the base tube frame build. Look forward to yours as it proceeds to completion. CNC looks like a rabbit hole to oblivion. I dare not stare into the light LOL

To give you a sense of the capabilities of this DIY machine have a look at this:
This is cutting 1/2 plywood at 8000mm/min.

Dropbox

www.dropbox.com

 

[DavidR8]

So a thing happened.
Nothing amazing. But I had to see if everything worked.
No magic smoke from the spindle or VFD
Coolant pump worked.
No broken endmill from crashing into any thing.
But I had my hand on the e-stop the whole time
Despite how much I've learned I now know how little I know and how much more I have to learn.
Still to do:
- Wire in contactor, physical e-stop, on/off buttons.
- Drill a boatload of holes in the enclosure for cable glands
- Install enclosure cooling fans (arriving Thursday)
- Route limit switch wiring in enclosure
- Route stepper cables in enclosure
- Finish spoil board attachment

 

[DavidR8]

More progress on the enclosure today.
Stepper driver cables in place and secured.

All cable glands except for the limit switches are in.
Top is spindle cable from the VFD, then stepper drivers, Ethernet cable and power.

Estop and on/off switches are in and working correctly.

 

[Dan Dubeau]

Nicely done. Very neat and tidy!

 

[DavidR8]

Nicely done. Very neat and tidy!

Thanks Dan. Lots of planning to get everything in and placed in a way that kept line and low voltage separate.
And I had to learn about contactors and latching circuits.
This project has been a tremendous learning experience for me. And I’ve not even started the actual design and machining aspect of it!

 

[DavidR8]

Had a big breakthrough with the UCCNC software tonight. I was struggling to get soft limits working. If I homed and then enabled soft limits I would get a message that a soft limit had been reached. Which didn't make any sense to me as the machine was at Zero on all axes.

Turns out that homing in UCCNC doesn't automatically zero the machine coordinates. There’s a checkbox on each axis to zero that axis' machine coordinates when homed. Checked them for all axes and entered the travel distances and now my soft limits work. Pretty darn happy about that!

 

[DavidR8]

Another big progress step.
I was struggling to get my AXBB-E board and UCCNC software to control my VFD which powers the spindle.
A bunch of research gave me some direction.

In the end I used the following connections:
VFD terminal AXBB-E Terminal
VI ---> AO1
GND ---> 5V0 (from 5V power out not 5V0 Port 1)
XGND ---> 24V0 (I took this from my 24V common)
FWD ---> Pin 7, Port 1

In the UCCNC software:
Spindle config screen: set "PWM Pin" to Pin 7, Port 1
I/O Setup screen: set "Spindle PWM -> analog ch" to 1

On the VFD:
Parameter 00.01 set to 1

 

[deleted_user]

I'm loving this thread... and how you've included sufficient bread crumbs for me to follow on identical build

 

[DavidR8]

I'm loving this thread... and how you've included sufficient bread crumbs for me to follow on identical build

Happy to try and keep it well documented. Good documentation was always a thing for me and this project has proven just how important it is. The manual for the AXBB-E board is good but the UCCNC manual could use a good dose of explaining what settings do.

I would never have figured out the soft limit thing had someone not explained two things:

1) that a different screen set was available that showed both work and machine coordinates at the same time. This let me see that homing zeroed the work coordinates but not the machine coordinates.
This is the screen set that I had to find. This is a shot after homing. Notice the Work Co. are zero but the Machine Co. for Y is -429.7450.
So when I enabled the Y axis soft limit of -264, the controller immediately said "Whoa there big fella, you're already out of bounds, you ain't going anywhere!" (or something that )

2) what the "Auto Set" checkbox did. As soon as I checked this box and homed the machine all the coordinates set to zero which allowed my Y soft limit of -264 work. (This is not a screen shot of my software but an example)

 

[DavidR8]

Designed and cut my first actual project on the router.

 

[YotaBota]

Looks like a wahoo moment!!!
You're either over designed or under tooled.

 

[DavidR8]

Looks like a wahoo moment!!!
You're either over designed or under tooled.

Definitely both!

 

[DavidR8]

I tried out vcarving for the first time.
Went ok in my books.

Tried using my corner finder today and ran into a bit of a problem.
When I tried to clip on the magnet that is connected to the DC0 I got a spark.
Eventually found a proximity sensor with an internal short sending 24v+ to the sensor body thus energizing the entire steel mass so connecting the DC0 lead was dead short and shut down the software.
New sensor is on it's way.
In the mean time I made a quick sensor mount out of acrylic to isolate the sensor from the frame.

 

[DavidR8]

Started rewiring my limit switches into the consolidation block.
Block is mounted at the end of the cable tray on the gantry.

 

[DavidR8]

These beauties just arrived. A gift from a member of Hobby Machinist.
Six Onsrud 3/8” solid carbide two-flute compression endmills. A cool $124 USD each!

 

[Tom O]

Your a lucky Son of a B!

 

[DavidR8]

Your a lucky Son of a B!

I'm a bit speechless to be honest!

 

[PeterT]

I had to look up 'compression' end mill. Is this a preferred weapon of choice for certain materials like wood or composites?

The Correct Way To Setup A Compression End Mill

www.stepcraft.us