Lulzbot Mini - total noob troubleshooting

As of Friday, I’m the proud owner of a Lulzbot Mini. Apart from two inductions at the local Hackspace, I’m a total noob as far as 3d printing goes.

I printed my Rocktopus and it worked great. However, after that first print, I’ve been unable to print the Rocktopus or any other model.

When I hit Print in Cura once the extruder and bed temperatures have hit their targets, the printer initialises the print head and bed positions (correctly based on visual inspection, i.e. they’re where I’d expect them to be within the frame.
Then, after a few minutes, the printer drops the temperature again and just stops.
Eventually the Print function aborts and Print becomes clickable again.

So, really dumb, basic question: how do I debug this? Are there logs to look at? Where do I start?

Many thanks in advance!

You might try manually loading a print profile to make sure the settings are correct. The profiles are available on the lulzbot site. If you haven’t already, download the latest Cura as well. Just to rule things out.

What’s the OS on the machine driving the printer? The latest MacOS has caused problems for some people. I wouldn’t expect it to act like that, but one more thing to consider.

Make sure the computer is set not to sleep or go into any other power saving modes. Some of those options can cause USB disconnects, which would cancel a print. Same thing with having the machine doing anything that maxes out the CPU or RAM. Try closing everything except Cura.

The print button is still there, so the computer can see the printer at least. That implies there might be something going on in the printer itself, but it’s hard to say with the little info we have.

Do you have another computer you can try? It would help exclude possible problems. Another USB cable?

Thanks for your response! I’m running the latest Cura on Win7/64.

I’m starting to think this is some kind of a pretty weird-ass memory management problem. The printer started working again after a multi-hour power-down of both the printer and the PC, but the model it is now printing is not the one I loaded into Cura, but one of the last ones (possibly the last one) that I tried to load and print before the power-down, when no printing was happening.

So I load a model into Cura, hey presto, printing actually starts, but the model that comes out it not the one I see loaded into Cura right there in front of me.

Which is really weird. I’d go with “gremlins” :wink: but for a more rational attempt at an explanation, I’m thinking there is some caching/memory management issue going on either on Cura on the PC, or failing that, on the printer itself. Does the Lulzbot mini have any persistent memory? If so, is there some way to remotely flush it?

I’ve heard of folks having a problem with Cura printing the previous print, rather than the one previously loaded. However, I think the "cure for this was to either close the print control window and clear the platform (or maybe clear the platform, quit Cura, restart Cura and load the new object?). Either way, if you powered down the computer and printer for hours, I would have thought that would clear this.

Make sure your PC is Not going into a power saving mode. I always turn my wireless connection off when printing so MS does not do a update or download when printing. I don’t think the Mini has a way to print from an SD card, if so you can try that.