Due to the amount of time (and money) it costs to design a 3D model and then 3D print it, we ideally want to be in a situation where we can start a 3D printer when we need to and turn it off when the print job is done. But let’s face it. We aren’t always in the situation where a 3D print job can be completed before having to stop the job, turn off the 3D printer, and even move the print – but interruptions don’t have to be the end of the world. Using a MakerGear M2 3D printer and the 3D printing slicing software Simplify3D, Vicky Somma was able to remove an in-process print job, pack it up, take it home and restart it exactly where it had left off.
Somma, an enthusiastic, self-taught 3D designer and maker whose work we have admired before, writes a blog dedicated to all things 3D, and her latest entry details how she restarted a print job that had to be stopped and moved partway through. After stopping a display print and unplugging her machine at the NoVa Mini Maker Faire, once Somma returned home, there were a few essential steps she had to take to be able to resume her print job again:
“Before I could resume printing, I needed to rehome all my axises so my nozzle had all its bearings, particularly the tricky Z axis. In this case, my print was not very high, so under the Machine Control Panel in Simplify3D, I was able to move the bed around to a good spot for me to hit Home Z without my print hitting the nozzle or the X axis support bar.”
With taller prints, it is trickier to home the Z axis. However, with the MakerGear M2, the Z endstop is set with a bolt on the side of the bed and it has a glass bed. You can remove the glass bed, home all of the axes, and then replace the glass. Print positioning can vary slightly when using this hack, but Somma reports this difference hasn’t been noticeable in her final prints.
Somma also acknowledges that, while there are downsides to using a USB cable to do a print job, there is definitely also an upside to using Simplify3D for this process:
“…in Simplify3D, you have a continuous update of exactly where the nozzle is, most notably how high it is in the Z axis. In the case of my Maker Faire print, I was the one that stopped the print, so I was able to note and record the exact Z position I stopped off at. That meant I knew exactly what height I wanted to restart the print at.”
If you don’t have access to information about the exact Z position where you stopped printing, you can always use the Jog Controls tab in the Machine Control Panel to “do some sleuthing.” This involves lowering the Z control of the nozzle after starting with the nozzle way above the print. Keep lowering until you are eventually using the -0.1 Z Control button, then pick a spot on top of which to move your nozzle. Using a business card, Somma gauged the distance, found where the print job stopped, and retrieved the Z starting point by referring “to the positioning information in Simplify3D.”
Next, to resume printing, use the Advanced Tab and the “Start Printing at Height” setting in Simplify3D. Also, go into the Scripts Tab and check out the “Starting Script” option. You will want to make adjustments here (like omitting the “home all axes” option since that has been done manually), altering any script that would cause the nozzle to collide with the print.
Of course, adjustments will have to be based on your own printer setup, but this information may translate to your own situation and help you when you have to stop a print, turn off the machine, and resume 3D printing at a later time.
You can also watch a video of these steps below. Is this something you are interested in trying? Discuss in the Stop & Resume 3D Printing forum over at 3DPB.com.