Topics

1

PoKeys / Can't turn off pin after M62

« on: January 26, 2023, 01:39:45 AM »

I have output 3 configured as laser output. M62/M63 work fine if there's a G1/G0 after it. But I cannot get it to turn off if I hit stop, or at the end of a program if I don't remember to add M63 and a G1 manually. (Fusion360 output skips the last turn off and expects M30 to turn it off)

I added

Code: [Select]

local hLaser = mc.mcSignalGetHandle(inst, mc.OSIG_OUTPUT3);
mc.mcSignalSetState(hLaser, 0)
to CycleStop() in the screen script, and to the M30 script, but it does nothing. I've also tried putting it in a separate M-code, which also does nothing. The only way I can turn off the laser after hitting cycle stop is to issue a MDI which takes a long time to type if I don't have it ready to go, especially since the control is on a touch screen with no physical keyboard. (M63 P3 G91 G1 X0.0001 G90)

M64/M65 P3 also does nothing.

Is this a bug in the plugin? I can't control the output in any way other than issuing another M62/M63 with a G1. I want to be able to turn off the pin without any motion.

2

Mach4 General Discussion / Surface mapping for lathe X axis

« on: March 31, 2022, 10:05:38 PM »

I'm thinking of converting my lathe to Mach4. The bed is pretty worn out and I'm wondering if the surface mapping functionality could be used in the X axis to compensate. It seems to do exactly what's needed - shift one axis by a certain amount based on position of another, but there doesn't seem to be a way to set it up in the X axis or in lathe mode. I know it's probably better to start off with a better machine, but it weighs 6000+lbs and was extremely difficult and costly to move into position.

3

PoKeys / Sudden pauses/stops

« on: February 27, 2022, 08:08:21 PM »

I'm having an issue with my mill suddenly jerking to a stop, it seems pretty random and will happen during cuts or rapid moves. No deceleration, just a sudden pause that I'm afraid might tip it over if I go any faster than 100ipm.

Has anyone else experienced this? It's happened on my old build that was much lighter so wasn't much of an issue, and my new bridgeport conversion where I'm afraid it might break something or tip it over.

4

Show"N"Tell ( Your Machines) / LMS 5500 (SX2.7) Conversion

« on: March 03, 2021, 12:05:17 PM »

Almost done here - it's moving and cutting! Still working on a few things to make it perfect. Quite a process.

Using PoKeys57CNC along with Clearpath servos, makes for a very compact install - everything fits in the machine body except the 75V power supply.




Had some significant fitment issues with the HeavyMetalCNC kit - apparently they changed the castings on the mills since it was designed. Did some of it on the machine itself while it was partially assembled (facing and eyeballed milling with a drill turning the ballscrew) and had to shop out 2 operations.

https://imgur.com/a/VGRrmky

• Top of Y ballscrew mount had to be trimmed to avoid clamping the chip shield solid
• Z motor mount holes didn't line up - epoxied original holes on the mill and redrilled + helicoiled
• X ballnut/mount wouldn't fit in the slot under the table - had a local shop mill off the corner
• At this point I could actually use the machine somewhat to modify it's own parts
• X spacer block needed to be taken down 2mm
• X spacer block then wouldn't fit over the ballnut either - milled the 2 radiused corners
• X motor mount needed new bolt slots since motor/ballscrew were misaligned by 3mm with the originals at their lowest point - had the shop make new slots and then I decked it down so the top was aligned with the spacer

Currently working on spindle control. Instead of using a simple 5V signal, on the buttons, the front panel board has some kind of digital signal going across them. I'm assuming this is to avoid accidental activation due to electrical noise, unless they're just making it a PITA to interface on purpose. LMS sells interface boards for their SX2 based mills, but not for the SX2.7 - going to have to make my own.

Reverse engineered the front panel board.


First thought was I could just connect 5V to the buttons to activate them - nope. The 1k resistor is a pull up for some kind of digital signal, didn't feel like pulling out the logic analyzer and decoding it. The buttons did activate when putting a diode across the leads so an optocoupler would work.

I couldn't figure out how to get the 57CNC board to activate it's optocoupled outputs in the right sequence and pulse them to simulate button presses though. The OC outputs aren't accessible from PoBlocks where I could do it. - Decided to lay out my own board, hopefully I'll be able to sell a couple of these for others that want a standard interface to the spindle.

On the plus side, the speed control is a simple 0-5V interface, and there's a 1k resistor on the board isolating the output from the potentiometer - easily overridden by a signal injected there.

Designed and laid out my own control board and currently waiting on production, I'll probably write the microcontroller code this weekend. It takes a standard spindle forward and spindle reverse input and translates it to simulated button presses. Also overrides the manual control knob with the speed signal while those inputs are active.



The board solders to the back of the original with slots in it to make contact where needed. It adds a new control header that accepts spindle fwd/spindle rev and a 0-10v speed signal that is divided to 0-5v and buffered so it can override the potentiometer output. Nice and compact.

I'll have 3 boards and only need 1 if anyone else has the same mill. Can do larger runs too.


Next project / first CNC project - power drawbar. You got a peek at the air cylinders in the first pics.



I have g-code for the first piece ready to go as soon as I get a few pieces of tooling I ordered, and my tool height setter. Need to get some practice with aligning my setups though - it's too wide on the Y axis for my mill! The bottom plate toolpath just barely fits. Haven't even gotten the mill fully set up and I'm already outgrowing it .

5

PoKeys / Access OC outputs on 57CNC from PoBlocks

« on: March 02, 2021, 03:37:48 PM »

Is there any way to access the OC outputs from PoBlocks while running with the Mach4 plugin? I'm trying to simulate a sequence of button presses to control my spindle on a SX2.7 mill.

The control board from the mill does something funny in the button circuit - simply connecting the button leads to 5V/GND doesn't work, but shorting them with a diode does, so the optocouplers should be able to switch them. There's some kind of digital signal going across the buttons.

I've worked out how to use PoBlocks to generate the needed pulses ("press" 1 button 100ms, next button 100ms), but need to use the optocoupled outputs to make it work.

I'd really rather not have to get out the oscilloscope and logic analyzer 

Reverse engineered button/lcd board: