How small can I expect FDM 3d printers to print?

Question

I was wondering if this printer(daVinci 1.0) had the ability to print very small objects, like insects, coins, or small nuts. (About the size of 1 -2 cubic centimeters)

Here is a link to the printer on the website.

The reason I ask is someone asked me if it was able to, but I have not been able to access the actual 3-D printer for use at this time, just manuals which I have looked through.

So if the 3-D printer was able to print small objects, would a novice be able to do such a thing?

Please let me know if any additional details are needed.

Answer 1

1) If we're talking about FFF/FDM printers:

Accuracy of the electronics and motors allows it, yes. But how FDM printers work it might be very hard to lay down layers of molten plastic so small as to preserve little details in the X and Y axis, not much of a problem doing 20 micron layer height though (Z resolution). Check this answer to find out what the X and Y resolution is and what it depends on: https://3dprinting.stackexchange.com/a/509/381

You'll need both a small enough nozzle, as well as somehow cool the plastic because since the printed objects are so tiny the nozzle keeps contact with the surface surrounding it and heats it longer, which might melt the whole object or even char it.

I've seen very few people do tiny prints with success. And the smallest nozzles I know are 250 micron. Not trying to dscourage you, just letting you know. If it was easy to do I think more people would be doing it and more companies would be advertising their printers as capable of such a thing

So you'll have around 20 micron Z resolution and around maybe 200 in the X/Y. If that's enough for you, then you could try. Calibrating it all won't be easy, tiniest backlash will be noticeable.

2) It's a lot easier with curing resin 3d printers (SLA or DLP). Most of them actually have trouble printing larger objects, ironically (trouble sticking to the bed and cracking of the 3d print). Even here badly calibrated lasers would prevent you from doing this and even many Form 1 users have reported their lasers being assembled poorly resulting in poor beam profile.

Size of the laser beam profile (aka laser "spot size") is what determines the X/Y resolution for SLA 3d printers. With the Form 2 its 140 micron, unless you'll get a badly calibrated printer. For DLP printers it's easier, it's the resolution of the DLP projector divided from the size of the print area.

Answer 2

Strictly by looking at the technical specifications of an FDM printer, there are a few things to note regarding the maximum print quality you can expect to achieve:

• The minimum layer height - here given to be 0.1 mm
• The nozzle diameter - here given to be 0.4 mm

Minimum layer height:

On a finished print, the minimum layer height will affect how visible the horisontal lines of the print will be. Printing at a lower layer height can dramatically increase the smoothness of the finished part, while equally increasing the printing time - among several other things.

A minimum layer height of 0.1 mm is fairly common for low-cost desktop FDM printers.

Nozzle diameter:

Just like the layer height defines the vertical resolution of a print, the nozzle diameter defines the sharpness of horizontal features of a print.

When printing with a large nozzle diameter, all sharp edges and corners of the model will have a slight roundness to them: the larger the nozzle diameter, the more rounded sharp corners will be, and vice versa. You might think of it as making a detailed drawing with a blunt pencil.

A nozzle diameter of 0.4 mm can perhaps be considered the standard for desktop FDM printers today, and will allow you to print "fairly accurate" parts.

Will the daVinci work for you?

Since I've never worked with the daVinci printer before, I cannot make a statement on it's user friendliness, or actual performance.

In general, if you intend to use it to print fragile, complex models such as insects, I believe a resin based printer might be more right for you, since they typically will allow for much higher reproduction of details than FDM printers. Printing solid/compact structures like coins and nuts, on the other hand, can typically be handled by a well calibrated FDM printer.