Foam has been cut!! :applause:
Only took about 4 or 5 failed attempts tonight before I figured things out.
Congrats, that's way less failed attempts than it took me to get things figured out
2) If the needle cutter is running and the stepper motors aren't, the Z height steppers will not be energized and the head will crash down unevenly depending on the location of the X carriage. Order of operations is to start the SD cut file, then reach over and quickly turn on the needle cutter while it's making the first travel move.
One thing you could do is connect the needle cutter line to one of the servo ports on the Ramps and use M280 commands to turn it on/off. You might be able to setup the CAM to use M280 as the "spindle on" command...but I'm not sure - it could just be inserted manually in the gcode easily enough. The one issue is RAMPS doesn't output a servo signal by default - so you'd have to do a M280 P0 S0 (assuming you're on the same port I'm using) to start outputting pulses which will cause the ESC to initialize. And then a M280 P0 S80 the 80 is a guess 90 is a bit too high on mine but is what I have programmed into my LCD controls for testing currently, you'd have to play around to find a good value but basically it's the servo setting in "degres" so 0-180. Since "3-4" works good on my servo tester I'm guessing something in the 60-80 range should be appropriate.
So what I'd do is at the very top of the gcode I'd add:
M280 P0 S0 // Start outputting pulses to allow ESC to init.
G4 S5 // 5 second pause to allow the ESC to initialize - may need more or less time
M280 P0 S70 // Set ESC to 70 degrees (since it thinks it's talking to a servo)
G4 S5 // 5 second pause to allow ESC to come up to speed and stabilize - may need more or less.
Then at the end of your cutting gcode you could also add:
M280 P0 S0 // Turn off needle cutter
Except...there's a risk it could stop with the needle down and snag. If you were to do this it may be worthwhile to do something like mount a magnet above the flywheel to encourage it to stop with the needle fully retracted. Or you could just add:
M400 // Wait for movement to finish
M280 P0 S0 // Turn off Needle
At the VERY end after it returns to home - that way it's not moving so it doesn't matter if the needle is fully retracted or not.
I'm actually getting ready to do this myself - just been lazy about experimenting to find the speeds/timings that work best for me. But I'm tired of having my servo tester tied up on the machine and really want to fully automate it.
I think in ESTLCAM it's possible to define start/end gcode like this...if not it's not that big of a deal to cut and paste it manually.
3) Need a hold down clamp to keep the foam spoil board from moving around on the worktable. I bumped it twice, throwing off the cut both times - especially the bump when it was in a travel move and not an active cut.
I just use carpet tape - but it's kind of messy and makes me not enjoy swapping spoil boards (I use a wooden one with my router.) My spoil board doesn't lay flat...none of the foam I found locally did. So clamps weren't enough. A few bits of carpet tape in the corners and middle hold it fine. Though this is why I'm wanting to switch to a vac table which can suck itself to the table as well was suck my work to itself.
4) Hitting the emergency power off switch to stop the Lowrider from moving works great - but since the needle cutter is on a separate bench power feed, it keeps right on making a hole in stuff.
I switched to that motor specifically since it can run at 12v off the same power as the CNC. But I'm still using a separate supply because the one I'm currently using for my machine is already at it's limits. (it's from an old mini emachines PC and is the smallest weakest PC power supply I've ever seen.) I have three other nicer PC supplies sitting there...but one isn't happy without a big load, one is being used to power my outside "stereo" (Just a cheap $20 wallyworld car amp hooked to some cheap 6x9 speakers), and the third I haven't got around to messing with yet. I've also got 3-4 other old PC's with good supplies I could scavenge but haven't got around to.
In fact cleaning up the wiring on my machine is something I've been really slacking off about. I got it good enough things don't get tangled while operating anymore but my RAMPS is still just sitting there on the table off to the side and my power plugs are just run off a heavy duty extension cord/power strip. I really want to add some outlets in the table and mount the RAMPS under it with the reset button re-wired to somewhere I can reach it. I also bought an estop button to wire into the main power so that's another reason I want to clean up the power wiring.
3) Build a spring loaded roller guide to prevent DTFB from bowing up in the middle. This seems like an easier approach than a vacuum table in the short term, especially in light of the success in the needle cutter thread.
Like David said - easiest solution for now is to put it crown down and pin the corners. It doesn't make it perfectly flat...but as long as you aren't trying to get your score cuts right up to the bottom paper it generally works well enough for me. Though the corners of my waste board are wearing out from all the pins going in and out in the same place
4) Reduce the overall length of the needle so less is flexing in the breeze below the guide.
I was going to suggest this
The needle should fully retract on it's upstroke. I try to keep mine no more than 8mm past the bottom of the guide at full extension so I have 2mm of headspace with the 6mm deep cuts I take for full cuts. Makes a big difference in accuracy having it shorter! I did leave my current needle a few mm extra long ~10mm fully extended - just so I'd be able to get more "sharpenings" out of it before having to replace it because I'm lazy like that
