So this is the first in a series of new making content that I will be bringing you through the blog. This test shows how the laser cutter handles raster engraving of different font sizes and how you can improve the quality of your engraving.

Our current set up uses 3 colors for 3 different intensities of raster engraving, light grey for light raster engraving, medium grey for medium raster engraving and black for heavy raster engraving. The way the laser cutter works is like an old dot matrix printer except instead of dots of ink it uses pulses of the laser beam. For the black the density of the pulses is the highest and you get good resolution. For the lighter engraving there is less density of pulses and this produces a lower resolution especially if the text or shape being engraved is small. This is most noticeable around the edges of the shapes and on curves or diagonal lines.

You can see what I am talking about below. With the smallest text pieces the resolution isn’t so great and some of the text is even missing whereas the heavy raster engraving has smooth lines and looks crisp.

One thing you can do to improve the quality of the engraving is put a vector engraving line around your text or shapes to make the edges more crisp. There are pros and cons for using this technique and it largely depends on which material you are using. Personally I like a heavy raster engraving on any of the plastics but a medium raster engraving with a medium vector outline on the timbers.

See below for more some detail shots of the different variations and make up your own mind from there.

In black acrylic –

In the technoply beech -

In eurolite poplar –

So this is a small selection of the materials but should give a fair indication of what to expect when raster engraving. Engraving on the timbers will produce a fairly similar result as the 2 shown and engraving on the other acrylic colors will have the same affect as on the black.

PETG or styrene are nearly impossible to photograph to show the differences in the engraving details and deserve a more specific post in the future. For now you can refer to this post in the forum which has a few tips in it.

Last week the 3rd year Industrial Design students at Victoria University presented the prototypes of the 3D printers they had designed. The challenge was to design and make a “green” 3D printer in 4 weeks with a limited budget. The students innovative thinking looked at ways to make use of waste material and repurpose it into new objects.

‘Stack’ used the waste paper from generated by a bank and a ’steampunk’ sewing machine to create layered forms based on an interpretation of the banks statistical data.

‘Nexus’ created forms by building up layers of bubbled gelatin. The results had some pretty amazing visual qualities.

And ‘Equinox’ focused the power of the sun to selectively dry layers of recycled paint to build up fluid forms.

This is the second year that 3D printers have been create by the VUW students, with the last years post here. It will be interesting to see what ideas they come up with next year.

Posted in Design, Fabbers, Digital Manufacturing, Dan Emery by danemery | 4 comments