Form 1+ 0.1mm vs. 0.025mm Layer Thickness
The Formlabs Form 1+ is capable of printing parts in three layer thicknesses: 0.1mm, 0.05mm, or 0.025mm. There are benefits and drawbacks to each of these layer thicknesses and each has its own applications. This page compares the extremes of the Form 1+’s resolution: 0.1mm vs. 0.025mm layer thicknesses.
Printing Speed – 0.1mm vs. 0.025mm
The most obvious difference between printing with a layer thickness of 0.1mm and a layer thickness of 0.025mm is printing speed. As discussed in the “6 Tips for using the Form 1+” post, the limiting factor of the Form 1+’s printing speed is the peeling operation that the print does between each layer to ensure prints release from the bottom of the resin tank. Since a model printed with a layer thickness of 0.025mm will have four times as many layers as a model printed with a layer thickness of 0.1mm, it will take four times as long to print.
Detail – 0.1mm vs. 0.025mm
The other obvious difference is that printing with a layer thickness of 0.025mm vs. printing with a layer thickness of 0.1mm means much better detail level in the finished print. Basically, printing with a layer thickness of 0.025mm means you will be able to capture smaller details in your print. So this is one of the ways you can decide whether to use 0.1mm or 0.025mm (or the intermediate 0.05mm) layer thickness. If you model is highly detailed, you might want to choose a smaller layer thickness. Along the same lines, a layer thickness of 0.025mm will be able to print smaller objects than 0.1mm.
Reliability – 0.1mm vs. 0.025mm
The downside to printing with finer resolutions is that the chance of having a print failure increases. For the most part, the Form 1+ is extremely reliable, but I do notice more failures when printing 0.025mm resolution parts than I do with 0.1mm resolution parts. From reading the Formlabs forums and doing my own experimentation, I think this phenomenon has something to do with the curing properties of the resin, the resin is not terribly strong while it is in the printer, it needs post-print curing to achieve full strength. I think, therefore, the really thin layers are more likely to fail than thicker layers. The 0.025mm thickness tends to work better with smaller prints.
Surface Finish – 0.1mm vs. 0.025mm
Last, printing with a layer thickness of 0.025mm yields a much smoother surface finish on the part. The 0.1mm layer thickness still gives very good surface quality, after all, 0.1mm is the width of a human hair. But parts printed with a 0.025mm layer thickness are so smooth that their surface is often shiny when dry. Take a look at the first photo on this page, the two 3D Hubs Marvin prints. You can see that the print on the right, which was done with a 0.1mm layer thickness, has a slightly dull surface finish, but the left model, which has a 0.025mm layer thickness, is actually quite shiny.