3D Printing is a time-consuming activity. Unfortunately, to reduce your print time, you cannot just increase the print time setting in your slicer. The result of printing a part at 100mm/s with a 0.1 layer height will not look as good as that same part printed at 50mm/s with a 0.2mm layer height. If you’re just getting started, you may want to hold off on looking for ways to speed up your print time until you have a solid understanding of how your machine works and how each of your slicer's settings affects your print. The main factors that influence print time are:
- Print speed
- Layer height
- Nozzle diameter
- Infill density
Print time is almost always inversely proportional to print quality, and settings are always dependent on the geometry of the part. It may take a bit of experimenting with your settings to find the 'sweet spot' for each print.
Here's a list to help you to think about the strategies you can employ to speed up print time:
- Orientation of parts—When printing multiple parts, work to arrange them on the platform in a configuration that limits the stringing between them and limits that stringing to the corners. This can both reduce the time it takes to print and the time it takes to cleanup your parts.
- Using a larger nozzle— Larger nozzle diameters will reduce print time, but will also reduce your minimum detail size and will round your corners a bit. If you use small layer heights with larger nozzles you will have a better chance of maintaining the surface quality of your print. But if your part does not have a great deal of detail, you can generally get away with combining a larger nozzle with a larger layer height. Use a larger nozzle when your minimum feature on the X and Y axis is larger than that of your nozzle size. If the part you want to print has a wall thickness of 0.6mm and your nozzle is 0.8mm, it will not slice correctly and you will not be able to print it. The easiest approach to start with is to slice with the nozzle that you want, then look at the layer view and see if the smallest detail shows up in the layer view. If it does, you are good to go. Keep in mind that the Z resolution is finer than the nozzle size and you will still be able to slice and see the features on the side walls if the details are smaller than your nozzle.
If you're experimenting with a 0.8mm nozzle, you can choose a layer height between 0.2mm and 0.4 mm. Change the wall thickness to 0.8 mm and your wall line count to 1. If you need to use infill, use more than you would with a 0.4 mm nozzle. You'll need more infill with the 0.8mm than with the 0.4mm nozzle because the larger nozzle produces more widely spaced infill. You’ll also have to work to figure out the right balance between speed and temperature. If your print is too droopy, up your speed. If the extruder makes clicking noises, raise the extruder’s temperature.
All models in the photos below were printed with a 0.8mm nozzle and a 0.3mm layer height:
- Infill density—Infill settings will affect print time and part strength (the maximum stress the model can take before breaking). More infill returns a stronger part, but with longer print times, and more resources consumed. Decide on your priorities. Do you want to minimize cost, save time, or increase quality?
- Design—For individual parts, speed is often a straight trade-off with quality. One strategy is to design your parts to be printed hollow. Printing with no infill will improve the speed and surface quality, but your parts will not be strong. Also when designing, keep in mind that 3D printed parts are weaker along their Z-axis than they are along their X and Y-axis.
- Maximum extrusion volume—Your nozzle can only extrude a certain volume of material at a time. This volume is determined by a combination of three settings:
- Print speed
- Nozzle size
- Layer height
Increasing any of these three values will make the printer extrude more plastic, meaning you will have to increase the print temperature to ensure that the filament gets melted quickly enough to be deposited at that speed, otherwise you will experience under-extrusion.
By default, the Ultimaker 2 and Ultimaker 2+ prints PLA with a 0.4mm nozzle at 210°C. If you change your nozzle to 0.8mm your temperature needs to be around 240°C.
- Wall thickness—If you know what you will set your line width to in your slicer, you can design your part with a wall thickness equal to that value or to twice that value. When you print, the walls of your model will require only a single or double-pass of the extruder to build, thus avoiding infill, and reducing your print time. Single-pass printing creates features that are extremely lightweight. For more strength design for double-pass printing.
- Higher speed—To print at higher speeds (150mm/s +) it is recommended to use materials that are optimized for high speed printing.