How to pause-mid print to insert a weight into an internal cavity?

I’d like to make a model that has a cavity inside that contains a small metal weight. The idea is to print up until the top of the cavity, pause printing, insert the weight, and then continue printing. This way, the metal weight is encased in the middle of the model to make it nice and heavy.

Does anyone have a good thought on how to do this effectively? One approach would just be to sit and try to hit pause at the right time, but I’m worried that I may miss on timing.

Are there creative approaches to this problem? I could imagine maybe altering the G-code manually, or perhaps splitting the model into two halves and trying to print the top half in place on top of the bottom half once it is finished, but am not sure about how to go about either of these ideas.

Any thoughts very much appreciated!



slice the model, go into preview, slide down with slider on the right to where you want to pause printing, right click + sympol …


That’s amazingly helpful and looks like just what I need. Thank you!

That’s a great tip - I was about to ask something very similar. Does the slicer not try to fill your void though? I would have thought with an open space like that, it will try to fill it with structure to support the lid of the void (if you know what I mean.

You have to either not use supports, or place a support blocker in there. I do it all the time with magnets.

Just a thought… if you split it in Half, wouldnt the weight become a possible problem should you pick the model up from the upper half? the danger being all the weight is at the bottom and may split again? Maybe a vertical split would be ok?


it is not really split it half - it is only paused to insert the something during printing. Afterwards you continue to print. Sure, depending on the weight it has to be calculated into the design.

When I’m doing this pause, the nozzle is not heating up again/purging before restarting the print, so my first layer after pause is always bad. I thought that adding gcode to purge after resuming would fix that. Someone tried this yet?

I haven’t tried this yet but just based off of the screenshot, you should be able to insert a purge manually if you select the “add custom g code” option.
While it might not be readily available in the slicer, it can absolutely be done in the g-code (even generated by another slicer).

To figure out exactly what you want:

  1. In the start of the file, look for what commands are used before and after “G92 E0” (resets extruder and prepares for new print)

  2. When you add the pause, slice it and check for any occurrences of “M104 S0” (turns off the nozzle and set the temp to 0c).

  3. The pause itself should be “M84” (which is an optional break).

You have many options in how you want to correct the issue for your print, but you can:

  1. keep the nozzle hot by removing the “M104 S0” entirely (or changing the setpoint)

  2. reset the nozzle + clear object of part if needed before or after, depends on the object you insert (I recommend reviewing a g-code object avoidance guide - should be a 5 min read)

3) Change the type of machine hold being used. M84 is technically a break, but there are other ways to do the same thing.

You can add custom commands to mimic a break, but without stopping by using various GXX commands to replace M84 with commands that move the nozzle off the part, stop flow and retract the filament without changing the extrusion temp of the nozzle. This is a bit more to learn, but you can do way cooler stuff with it. You can even generate the commands from SolidWorksCAM or CNC applications like Tormach CNC’s conversational editor or online training tool.

Doesn’t the button in top of the X1C pause an active print? I didn’t try it yet…The one on the right (I think) is supposed to pause the print…or is it to kill the print?

Yes, that Pause button at the top of the X1 C does pause the job, but the user can be smarter than waiting in front of the printer for the right moment, and instead find the layer (via the Preview tab and the vertical thermometer) and input a pause when he needs it.

That’s interesting, how do you set a pause at a certain layer?

Slice the plate, Grab the green Plus sign at the top of the preview slider on the right side of the window with mouse pointer and slide it down to the layer that you want to add pause to, right click the Plus sign and select add pause, re-slice the plate you will see the pause indicator on the slider.

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