3D Print Technologies - Three Tanks from Three Technologies

Here is the precursor to this article.

Note that I am focused on appearance here and not on time to produce or costs.  I may try to tackle those aspects in another article at a later point but for now...just the cosmetics!

So here are images of three tanks printed by three different technologies and then base coated so they would be the same color (the FDM print was grey, the SLA print was white (but sorta clearish), and the SLS print was white).   All three prints are at 100 microns of resolution.  Note that full scale images are at the bottom of this post.

First, however, a quick look at the prints as they come out of the printer (but after support removal):

The SLS print is far left, the FDM print is in the center, and the SLA print is on the right.  Unfortunately I forgot what order I had used above so the rest of this page will have the order being FDM, SLS, and then SLA.  Sorry!

The images below are of the three models with a quick coating of Panther Yellow so that you can actually see details which are harder to capture in white.  The order is different to the above.  The FDM print is on the left, the SLS is in the middle, and the SLA is on the right.

Here are the side views of the three prints in the same order top to bottom as they were above left to right.

Finally, the close ups of the back of the vehicle and the details from that area.

Here is my commentary on the above.  No particular order just as the thoughts come to me!

1. The quality when looking at details is SLA, then FDM by a margin, and then by more of a margin the SLS print.
2. The cost of producing these prints (whether you own the printer or buy the print) are highest for the SLS and SLA prints and by far the lowest for the FDM print.  SLS and SLA printers are very expensive and expensive, respectively.  SLA material is expensive (not sure about SLS) but FDM printers and material are pretty cheap.
3. The post printing effort that goes into preparing a print for use is the greatest for FDM, then SLA, then SLS.   FDM requires a fair bit of support removal and then cleanup from the removal.  You will note on the tracks of the FDM print that some of the support has not been properly cleaned up.  The SLA print also needs support removal but the process, while not trivial, leaves a very clean result.  The SLS print requires no support removal at all.
4. The FDM print has some surface imperfections (holes) that are noticeable in this magnified image but are not to the unaided eye.  These holes are the areas at the corners where extrusions have not merged properly.  They are not uncommon but are also not supposed to be there!  I can tune them out but wanted to get this article done...so there they are.
5. The surface of the SLS print is an artifact of the printing process where a laser is used to compress, not melt, plastic in a powder form.  This surface also seems to drink paint.  I don't like it for AFVs.
6. The SLA print is the most predictable, the most crisp, and portrays less evidence of support material having been in place than the FDM print.

Based on the above, if I had no constraints I would want an SLA printer.  There are some major downsides to the SLA printer though with the first being the cost of the printer (though they are coming down) and the second is the cost of the material (resin) that it uses.  The other downside, for me anyway, is that resin and it's potential for mess and the requirements for cleanup of the print.  Support structure removal on an SLA print can be as challenging as from an FDM print as well.  I am sticking with FDM!

Here is the precursor to this article.
Here is the successor to this article.