Using OctoPrint without a bed sensor

The line you want to comment out is highlighted

This is a rather selfish post, in that it is here so that I can find it in my blog if I need to do it again. Although if you’ve just tried to use OctoPrint and had the print fail because of a “Bed Levelling Not Enabled” error you might find it useful…

Anyhoo, a while back I disabled the bed level sensor on my printer, what with its habit of bashing the print head into the print bed every now and then. I decided that I could manage without automatic bed levelling and things have been going fine. I’ve been copying my print files onto an SD card and plugging it into the printer. But today I decided to reconnect my OctoPrint server. This is useful because it means I can print directly from my computer rather than hopping around with memory cards. But it didn’t work. OctoPrint kept shutting down the printing with an error.

I eventually tracked down the problem, and it wasn’t OctoPrint. It’s just that OctoPrint cares when the printer sends out an error message, whereas if you print from a memory card all printer errors are ignored.

The problem is with Cura, the program I use to convert my designs into code files that control the printer. Cura adds a header of instructions to the printer code file. One of these was asking the printer to turn on bed levelling. The printer complains it hasn’t got bed levelling, sends out an error message and OctoPrint stops the print. The solution is just to comment out the M420 statement that does this, as you can see above. To get to this menu you use Settings>Printer>Manage Printers>Machine Settings