Introduction: Cut 3D Print Times in Half With Negative Volume Printing

By DreadMakerRoberts
About: Special Effects designer, nerd, maker, a monocle and high collared cape away from being a mad scientist.

Traditional 3D printing takes a long time. By looking at the 3D model as the negative space, or where NOT to print, you can make a model that prints in vase mode much faster. In some cases, prints take half the time! I am calling this technique ‘Negative Volume Printing’ or NVP for short.

Using this method you can:

  • Speed up print time
  • Retain the quality of your prints
  • Have more control over the structure

Supplies

Check out this quick video I made on the process. Don't forget to subscribe and hit the notification bell while you're there.

Step 1: NVP Plate Example

The basic idea of NVP is that you can print the shell of your object in Vase Mode.

There are a couple of things to keep in mind:

  • I print with a really fat nozzle - 0.8mm
  • 0.4mm gives you all the gaps that you need

We'll start by looking at this concept using a flat plate. You need to add slots along the length of the plate that are 0.4mm wide and stop 0.4mm short of one of the long walls of the plate. This allows you to print in Vase Mode or 'Spiralized Outer Contour' but also adds needed supports to the object. The machine follows the outline over and over again without stopping, slowing down or retracting.

Step 2: NVP Enclosed Object Example

But how do you print an enclosed object using this method? You add slots to the object, the same way you did with the plate. All the slots but one should stop short of the outer wall, similar to the plate example. One slot needs to go all the way through. This lets the machine print the outer wall and supports in a continuous spiral.

Step 3: NVP Moai Statue Example

I wanted to show this method using an actual model. I downloaded a free design from Cults: Moai Statue - No Overhang. Make sure you go to Cults, download the file and tip the designer Julien_Dacosta .

Moai Statue No Overhangs. 4” tall Cults. https://cults3d.com/en/3d-model/art/moai-statue-no-overhang

I imported this design into Cura and if I printed it normally, it would take 2 hours and 33 minutes.

I decided to see how long it would take if I printed it as a shell. I thought it would save some time. According to Cura, the print time would still be 2 hours and 32 minutes.

Using my NVP method, it cuts the print time down to 1 hour and 25 minutes! Obviously this not quite half the time, but it's a significant difference. I've found the larger the model, the more time that's saved.

Side note: I used lightweight PLA for these models. I highly recommend you check it out. It expands as it comes out of the nozzle, which makes for a super light print. It's quite tough and VERY easy to sand.

Lightweight PLA: https://amzn.to/3ylSVlc (This is not the stuff I used in the video but it's just as good)

If you want to try printing my NVP version of the Moai Statue, you can get it here: https://www.printables.com/model/196346-negative-vase-printing-moai

I plan on doing more videos on this method, including how to print a helm. I'll also be offering the files to my Patrons. If you'd like to sign up for my Patreon, you can do it here: https://www.patreon.com/beneadie