The aim of the research was to investigate the usability and legibility of 3D printed typeface characters in smaller sizes. In the experimental investigation two software programs for letter modelling, three typefaces, three type sizes, two weight options, and two printing materials were tested. The samples were analysed visually and with image analysis. The legibility tests were conducted in laboratory conditions and testing chamber. The participants were asked to read pangrams and answer close-ended questions. The reading speed and understanding of the text were measured and analysed. It was found that the success of printing parts of letters, as well as their recognition and visual evaluation, is most often influenced by two analysed factors, i.e. weight option and type size, in all three typefaces. We established that the type size is statistically significant, and that the typographic tonal density is influenced by the typeface and the material used.Practitioner summary: The research presents the investigation of usability and legibility of 3D printed typefaces at smaller sizes. Five variables were analysed visually and with image analysis. Typographic tonal density, reading speed, and text comprehension were evaluated. The findings demonstrated that weight option, type size, and material influence the reading speed and text comprehension.HIGHLIGHTSFive different parameters were investigated regarding usability of 3D printed typeface.Legibility of different typefaces, weight options, and type sizes were tested.Typographic tonal density was evaluated with image analysis.Print quality of different materials using an FDM technology printer was evaluated.
Keywords: 3D printed typeface; FDM technology; legibility; multivariate analysis of variance; typographic tonal density.