Does one has to take into consideration the nozzle diameter while designing something that will be 3D printed?

Question

I am really new to 3D printing. I started with downloaded stuff about 2 months ago and now I am starting to do my own "easy" things.

While looking at tutorials I heard one of them talking about doing a chaffer of a specific size/height because he had a 0.40 mm Nozzle (the same as the one I have with an Anycubic Vyper). This got me thinking about if I should also take into consideration my Nozzle size for when I try to design something.

For example, should I think about multiples of 0.40 mm when deciding overall lengths or heights?

If I need to create space between 2 pieces, or joint pieces, should I always have to leave a multiple of 0.40 mm space between those pieces?

I have tried to find out info about this but I just found info about the importance of the Nozzle size at the time of print, but not at design time.

I am using Fusion 360 if that info is needed.

Answer 1

Nozzle size isn't what matters most time - Line width is

On many printers, it is actually common to print with a line width larger than the nozzle size. This is typical for many i3 style machines, such as Prusa I3 or Ender3. For a 0.4 mm nozzle on those two, the standard line width in Prusaslicer is set to 0.45 mm.

On Ultimaker Machines, the default in several slicers on the other hand is nozzle size to slightly lower (0.4 or 0.38 mm).

In any way, the factor you should remember here is the line width set in your slicer, which is dependent on the nozzle diameter. However, that is not the nozzle diameter itself.

When to use line width in designing

It is generally not advisable to design parts that are less than one wall thick. The slicer will usually drop those sections or, if not outright ignoring those sections, will result in considerable print artifacts. So, as a rule of thumb, the line width is the minimum thickness you should design for.

If you try to create sturdy walls, such as for containers, using an exact multiple of that line width is very common, which in turn creates very fast layers: two perimeters of 0.45 mm come out as a 0.9 mm wall, three to 1.35 mm, and so on. But that all depends on your line width.

When to ignore line width

If your item isn't structural in any way, forget anything about line width. Just design your aesthetic parts, and only in the end make sure that thin sections are at least one line width thick - by tossing your item into the slicer, check which sections are ignored, then thickening just those areas till you are happy with the approximation of the slicer.

Answer 2

It would depend on what you are printing and the tolerances that you require.

For example, if you are producing engineering parts, and are a skilled designer, then you should take the nozzle size and layer height into consideration. Though the order of wall printing will probably be of more interest to you (If you print the inner walls first then the outer walls might bulge outwards slightly, and vice versa).

If you ware making garage kit style sculptures and busts, then you don't really need to think about the nozzle at all. Your slicing software will automatically adjust the print to fit what is possible and the slight differences won't make much of a difference.

If you're trying to print warhammer size figures, then yes you do need to take the nozzle width into consideration as it will effect the small details that you print. Which is why people mostly choose resin printers for this scale.

If you're only an average skill designer making items that don't require extremely delicate details or high tolerances for practical parts, then don't really need to even think about your nozzle.

I have an Ender 5 that's still using the 0.4 mm nozzle that it shipped with quite happily.

TLDR: If you're new to 3D printing and aren't trying to print Warhammer figures or engineering parts, you can largely forget about your nozzle. You won't notice the difference until you're much more skilled at modelling and are looking to do resin quality tollerances.