Monthly Archives: October 2012

3D Modelling Materials

Custom Parts for Ikea Lillabo Train Set

The wood composite seems well suited for printing some custom parts I designed to supplement the Lillabo Train Set from Ikea.

The parts printed out well on the first go, with only minimal clean-up required due to the oozing. The circle part of the buffer still had a hole in it even though I set the solid layers to three (infill=20%), but adding a red sticker easily solves that.

It makes me think that a useful feature for a slicer would be to gradually increase the infill for the last few layers, i.e. 20% on layer n-3, 40% on n-2, 80 on n-1 and then 100% on the top.

Materials

More Wood Composite Observations

A quick post with a couple more observations on the wood composite together with some photos.

Sam’s Gears

Whilst printing a tray of the excellent Sam’s Gears by pleppik I wanted to reduce ooze so I increased the speed and also the temperature to 230°C, and midway the extruder jammed due to a blocked nozzle. At higher temperatures the composite turns darker and becomes harder, and it may have been this that caused the jam, or possibly some other detritus. It could also of course been caused by something other than the material, however this is the first time this nozzle has jammed. Generally going slower and cooler seems to be the best tactic.

The Venetian Lion by tbuser I printed scaled down 50% and 25%, and with support. The support came away quite easily, but I can’t compare this to other materials as this was the first print I have done with support. The temperature was set to 220°C and layer height was 0.24, this produced a finish more akin to brown PLA rather than a “wood” finish.

A couple of Simplified Gekko’s by CodeCreations were next to test the hypothesis that visible layers look better with the wood finish. Whilst not terribly beautiful prints, the colour and texture detail, particularly of the heads, are quite pleasing.

Dizingof’s Dragon Bowl came out quite nicely, but highlighted a problem which crops up frequently: the latest version of Slic3r seems to jump around a bit, particularly when infilling, and because of the ooze problem this results in imperfect finishes.

Dragon Bowl

I printed out 2 copies of the bowl, one at 220°C and another at 185°C. The latter is lighter in colour, this is also clearly visible in the Sam’s Gears print, where the crank handle was printed cool, but the gears hot. Another property I am seeing: prints at lower temperature are much more compressible (spongy) and flexible. The pins I printed for Sam’s Gears were so flexible they were not really usable (hence the bolts instead). The texture at lower temperature is also more “wooly” and woodlike. Several of the prints, such as the pin board, have quite a look of MDF about them.

Sam’s Gears, Crank Detail

Whilst testing how paint applies to the material I realised that I hadn’t yet tried painting regular PLA. Surprisingly, at least to me, the PLA also took the water-based acrylic paint I tried well too – so long as the surface was sanded beforehand. The wood composite took the paint well without sanding, apart from the bottom plane, which is quite glassy. This would need to be sanded before applying a coat, otherwise the paint peels off quite easily.