AndyUK's Build - 1.2x1.0m Gantry

[AndyUK]

Thought it might be interesting for others designing their control boxes to see why I've made my new one like this and how it works. Also welcome to hear any improvement suggestions.

My typical workflow is:

• Turn on the CNC & PC (UCCNC Autoboots)
• Reset the EStops (Red momentary reset button lights when safety circuit is tripped) & Turn on the wireless (bluetooth) Xbox controller.
• Enable the motor drivers on the control box (Purple latch button - lights when motors enabled).
• By this time UCCNC has loaded, so use the Xbox controller to do a software reset on UCCNC (the start key).
• Home the CNC. This can be done by pressing the (white) Zero button on the control box. This button homes if the CNC isn't homed yet, otherwise it resets the X&Y position to zero if its lit up. The button only lights up when the CNC is idle (i.e. stationary not running a cycle or dwell), homed, and the spindle is off.
• Load the GCode using mouse & keyboard.
• Setup the work piece & do a tool change.
• Set the X&Y zero coordinates, positioning with the Xbox controller, then press the Zero button on the control box again.
• Set the Z zero coordinates using the touch plate by pressing the Probe button (Orange latch button - lights when a probing routine is running or soft probing mode is enabled) which runs the auto-tool height setting macro.
• Limits & work holding checks.... If I do somehow hit a physical limit (only really posibile at startup due to softlimits) the yellow LED illuminates to indicate an inductive limit switch is triggered. Pressing the latch button allows limits override until the switch is released, at which point the LED turns off. Softlimits can also be toggled at any point with this switch.
• Engage water pump if needed.... (Blue latch staight to relay in control cab)
• Press the cycle start button in to start the cut. The cycle start button is a green latching button that lights when a cycle is running.
• If needed, releasing the cycle start button will feedhold.
• Engage mist if needed.... (Blue latch staight to relay in control cab)

I've recently updated to Windows 10 just so I can have this wireless bluetooth controller. Expensive? Yes.. Awesome? Totally. I'm using Crafty CNC's Plugin to give extended functionality, I tried it a year back and wasn't too impressed, but after trying again and ironing out a few bugs I'm really happy with it now.

The left analogue stick gives up and down control over the Z axis, varying in speed cubicly between 0-50%. Holding down the left trigger at the same time changes this to 0-100%. This means you can quickly get to the right position, but have very fine positioning control as well. The right analogue stick and trigger do the same for the X and Y axis. I've set the ABXY buttons to also jog X and Y with feedrates controlled by the left and right bumpers, this is really helpful for large innaccurate rapids across the table, or if you want to be sure to constrain motion to just one axis.

The "Start" button on the controller is set to toggle the software reset on UCCNC. This is good to get things started, and is effectively an E-Stop button for the controller. The "Menu" button is set to toggle feed hold as a mobile pause button.

This leaves the 4 Dpad buttons free for assigning to other functions I haven't quite decided upon yet... :)

I've also got a docking station to keep the controller charged up and give it a nice safe "home"! - Oh and you see that single board PC sitting on my subwoofer? Thats what I run UCCNC on. Its a quad core i5 @ 2Ghz per core, 8GB ram, 256GB SSD and with some serious integrated graphics.

[Nickhofen]

Awesome,thanks for sharing!

[Kitwn]

Nice setup Andy. At the other end of the Xbox budget range I'm using the plugin built into UCCNC and a dirt cheap USB Nintendo style controller which works OK for jogging and Z zero setting but going wireless would be very helpful. Understanding how to use the probing control is on my ToDo list.

The only thing you might add would be a hard-wired interlock switch for the spindle when doing manual tool changes. I have one which interrupts the start wire from the controller so that no accidental button press or software glitch can spoil my Jimmy Page impersonations.

[AndyUK]

Understanding how to use the probing control is on my ToDo list.

Z-Axis probing is a complete game changer, I really don't know how I went without that initially. So simple to setup as well; just have a 0V clip on to the tool (I've cheated and run a dirty 0V line to the spindle holder), and a second "Probe" line from the UB1 to a block of aluminium. Setup one line in UCCNC, and you can use JSP (jog safe probing) immediately which is great for X&Y. Measure the block thickness and quickly google a tool height setting macro, and within 10mins you'll have perfect and automated Z height setting. I'm now looking into having a permenant block in one corner and letting it have a bit more automation on those tool changes, but one step at a time.

The only thing you might add would be a hard-wired interlock switch for the spindle when doing manual tool changes. I have one which interrupts the start wire from the controller so that no accidental button press or software glitch can spoil my Jimmy Page impersonations.

Thats a great idea - I've shyed away from anything contactor/relay like on the power side of the VFD, but theres nothing to stop me putting a relay on the control logic side that would drop it into a safe state. Still not completely foolproof because short of powering down the VFD at every tool change theres always some risk the high quality chinesium in the VFD will go haywire....

[Kitwn]

Z-Axis probing is a complete game changer, I really don't know how I went without that initially. So simple to setup as well; just have a 0V clip on to the tool (I've cheated and run a dirty 0V line to the spindle holder), and a second "Probe" line from the UB1 to a block of aluminium. Setup one line in UCCNC, and you can use JSP (jog safe probing) immediately which is great for X&Y. Measure the block thickness and quickly google a tool height setting macro, and within 10mins you'll have perfect and automated Z height setting. I'm now looking into having a permenant block in one corner and letting it have a bit more automation on those tool changes, but one step at a time.



Thats a great idea - I've shyed away from anything contactor/relay like on the power side of the VFD, but theres nothing to stop me putting a relay on the control logic side that would drop it into a safe state. Still not completely foolproof because short of powering down the VFD at every tool change theres always some risk the high quality chinesium in the VFD will go haywire....

Thanks Andy, I will read up on the UCCNC probing.
I take your point about the chinesuim (lovely word by the way. I'm rather proud of having invented the word 'polycrapoline' to describe the cracked-within-weeks material used in some HV breakers I had the misfortune to work on many years back). It's for each of us to decide the level of risk we are willing to accept in our home workshop.

I was once very shocked to find an interlock system in a former employer's premises which, when made 'safe' left an HV power distribution transformer able to be back-fed if a microscopic transistor inside a PLC microchip went short circuit and decided to power an external relay which would close an HV breaker which was NOT included in the electromechanical interlocking. The risk I'm taking in not powering down the VFD every tool change is similar but the consequences, though potentially serious, are not guaranteed fatal and I only touch the sharp tool itself for a few seconds.

[AndyUK]

I've recieved a question about my UCCNC setup, so thought I'd share and discuss my config in public, just incase it helps a future builder.

The vast majority of these settings are taken directly from the UB1 manual, where there is a section on UCCNC and Mach3 setups. All the port and pin settings are taken from the UB1 manual, in combination with my circuit diagram.

Axis Settings (X/Y/Z/A)



Note slaving of X and A. X&Y Steps per is pretty self explanatory (200 steps per rotation on the steppers, 10mm pitch screws, 8x microstepping = 160 steps per mm). Z is 5mm pitch so 320mm. Y&Z use a travelling inductive limit so port and pins identical. X&A have independent static switches for home and -ve limit, but share a +ve limit switch. Speeds and accelerations are set quite conservatively to avoid stalls.

Spindle Settings


As per manual, nothing special here.

General Settings


Mostly as per UB1 manual, but note use of soft limits, ignore unknown gcode (bit risky), M6 pauses for manual tool changes, & homing sequence.

Input Settings


As per manual, nothing special here.

Input Triggers


These handle my control box switch inputs, you can make the same switch have multiple actions, some occur on depress and some on release (hence the low tick). If you see high numbers in the function code its a custom macro to do more complex actions, like my Z height probing or my Zero button which does homing or X&Y zeroing depending on the machine state.

Output Triggers


These exclusively control LEDs on my control panel, alongside some of my macroloops.

Xbox Controller Settings


See my previous post to discuss these.

[AndyUK]

Robertspark's UCCNC Macros, Screenset and MODBUS manual is also a very helpful reference. See attached. Not only does it highlight all the inbuilt macro functions, but also has tables at the end listing the inbuilt function codes and LED codes.

[AndyUK]

I take your point about the chinesuim (lovely word by the way. I'm rather proud of having invented the word 'polycrapoline' to describe the cracked-within-weeks material used in some HV breakers I had the misfortune to work on many years back).

Chinesium is one of many AvEisms - search AvE on youtube, you're in for a treat. I suggest starting with some of the BOLTR (Bored of lame tool reviews) which are extremely informative teardowns and tests of various powertools. He is a bit of an interesting character, but well worth watching. And of course ThisOldTony needs a mention - especially his CNC build videos.

It's for each of us to decide the level of risk we are willing to accept in our home workshop.

I totally agree, and please don't take my words as any endorsement or critique; merely just my rambling commentary on which failure modes I think your suggestion protects from and those it doesn't.

[Kitwn]

Had a quick look at AvE. One to listen to while I'm doing something else. I watched a few ThisOldTony videos ages ago and had forgotten about him. I hope he doesn't read this and take it personally! My favourite YouTuber is Sped Spedding. I don't think he knows anything about CNC but he sure can play a guitar like ringin' a bell!

Kit

[AndyUK]

My wife and I had our first child over the summer, so haven't had an awful lot of time in the garage....! But I have managed to apply the inlay technique to build a set of toy blocks for her to play with. The faces you can't see spell out her name, and my wife picked out a number of shapes that mean things to us - there's at least two of everything so she can play match the shape too!

Hope everyone is doing well,
Andy