Ignore gcode for a part that falls over mid-print.

[moo10032]

When printing multiple parts in a single print sometimes a piece will get knocked over. The printer will keep trying to print on top of where it was which can cause a lot of build up and in most cases causing a chain reaction knocking over many move pieces. Typically for me the nozzle will just take the mid-air noodles and drag them all around and it will slowly build up into a blob on the hot end itself which is not good... This mostly happens half way through a tall print and its a waste to restart, especially if you have lots of other pieces half done on the same platform.

Only solution right now to a part falling over mid-print is babysitting it the rest of the way cleaning the noodle mess from the missing piece, or restarting the print. I find simplify3d's "start at height" feature really hard to use. It will either start a layer too high, or start into the last layer causing more problems trying to print directly into the last layer.

Some way to be able to select the part from the printing preview screen and tell the printer to skip this piece for the rest of the print without interrupting the print. Maybe like a "ignore" button, and you drag-select the gcode preview, this wouldn't work if you do a SD card print, but from the computer printing it should be able to simply change the gcode on the fly, maybe it pauses the print temporarily while it re-calculates the new gcode. Any input on this?

[JoeJ]

You should be using sequential printing: https://www.simplify3d.com/support/tuto ... -printing/

[moo10032]

I find sequential printing not suitable for small parts due to overheating. If a part is too small it does not allow enough cooling time and the layers will deform. I've found doing the entire print 1 layer at a time will keep everything crisp. I also enable "print island sequentially without optimization" because the last part on a layer would switch up one layer and print right over the same small piece. I had really weird overheating issues with that. Some kind of feature as I described in my first post would be ideal.

[sstantz]

I definitely agree this would be a really cool feature.

For me, and certainly a lot of other people, sequential printing is rarely appropriate. My toolhead is bulky. The fan at the nozzle needs to be removed for sequential printing to work, even for low-height parts. If a part fails, it would be great if I could tell the g-code sender (S3D) to simply no longer send the g-code for a particular part.

I don't think it should be too difficult to implement. The g-code would just have to be written with a comment that can identify what commands are for each part. Movements would have to use absolute coordinates, like usual, but the extruder steps would have to be relative.

[jimc]

I really like the idea of ignoring the gcode for a certain part. There have been many times where that would be useful. As for sequential printing. That feature is awesome. I use it all the time. Its an absolute must when printing multiple ninjaflex parts. Cooling does need to be taken into account as always. No different than printing a single model. Its a great feature though.

[billyd]

When printing tall objects or if you are having trouble knocking parts over, enable retraction vertical lift and set it to .4mm or so. Then when you do a travel there will be a retraction and a z hop and you won't knock over your parts anymore.

[lkeppner]

You're assuming that the only reason parts fall over is because we have "hit" them with the nozzle. There are times that parts "fall over" just because they are not adhered properly to the glass and the drag from normal printing will pull them off the bed. So, while increasing your z-lift upon retraction is very helpful, this does not address the issue of "skipping" a fallen part and reducing the waste of material and time (not to mention the mess it creates). I have had times that this would have come in VERY handy. It sounds complex to program because you would have to regenerate the g-code and then "pick up EXACTLY" where you are currently at in your print... perhaps it could be set to implement the changed code at only layer changes???

[neveroddoreven]

I think this is a great feature request and could have used it a couple of times now for exactly what moo10032 said: a part simply detached because it had poor adhesion in that particular part of the bed, or perhaps it needed a brim more than the other parts. I hate having to either abort a bed full of half-printed parts, or chasing the print head around with forceps for the last 15 or 20 layers to grab filament loops in vain to rescue the rest of the parts.