Well, I’ve been using cncjs more and more and am really starting to like it. Still not huge on using it with Marlin…but haven’t had time to get my GRBL board going.
However this weekend I cut 15 sheets of foam on the MPCNC back to back mostly using cncjs (a few sheets I did off the SD/LCD still because my pine64 fell off the network when I wasn’t using it and I didn’t want to wait for it to reboot and reconnect.)
I’m still not huge on how Marlins queue makes the cutting display less than accurate and makes canceling an operation slow…but that’s marlin’s fault not cncjs.
However I did have three odd issues this weekend and I’m not sure if they’re cncjs related or Marlin related. I’m fairly sure they’re not hardware related because it seemed to do the same thing twice and the third time was really odd.
The thing that happened twice at first I thought was mechanical and a case of something jamming causing me to loose steps…but it didn’t look like it lost steps…it looked like it went backwards for a second then forward again. Caused the same loss of position that missed steps does - but it didn’t miss it reversed. It happened so quick though I figured I just imagined it moving backwards and it really was missed steps. Except then a few hours later it happened again and this time I was sure I saw it move backwards. No idea what could cause it … but I am on an old two year old build of Marlin still so highly probable it was Marlin hiccuping due to being controlled over USB instead of reading gcode off SD.
The third issue was crazier. It was cutting a rectangle with 4 score cuts down it. The score cuts came out great, but the outer cut (all my foam cuts are “engraving” cuts in estlcam since I want them right on the lines) only cut two sides…but it cut those two sides twice ?! The gcode looks correct, the preview in estlcam and in cncjs looked correct so no idea how that could happen. Thankfully it was a piece I didn’t actually need so no big loss…and no lost steps so everything else stayed aligned.
Overall a great weekend for the machine. All 15 sheets were for other people though and after cutting them I thought one of the designs looked like fun to build for myself so I loaded up some more foam and got started on it.
I should note that I’ve been putting off sharpening my needle for some time and it really does need it. The cut quality had definitely deteriorated over the 15 sheets…still acceptable but the bottom layer of paper wasn’t cutting quite as cleanly and I could see the needle starting to drag while cutting. After my first year with the needle cutter having so many failed needles and needles getting tossed off the cutter it’s been great having this super reliable for the last year.
Well, halfway through the second sheet for myself last night my streak with this needle ended. Things suddenly got quite a bit quieter and when I looked over there was no longer a needle 
The little ring that holds it on the bearing was still there but right where it bends it can snapped.
I can’t complain though. That needle has served me very well. Over 20 planes for myself, at least half a dozen other foam projects, a couple of cardboard projects (not a great idea - way hard on the needle) and probably more planes cut for other people than I did for myself. I’d say it went through somewhat more than 100 sheets of foam all together. All without me even sharpening it despite knowing I should.
But now I’ve got a good excuse to try one of the 3D printed needle retainers instead which eliminates the bend where it snapped. This needle lasted 10 months of heavy use…wonder if I can get 12 months out of the next one 
And maybe I’ll finally upgrade to a newer version of Marlin to see if it eliminates these odd issues I’m occasionally seeing with cncjs.