The 3D Model
Dharroun's Model was sculpted in Maya and Mudbox. It is an intricate model with fine surface texturing and details and is really intended to be printed on a SLA 3D Printer like the Form 2. We don't have a Form Two, but we can preserve most of the detail by printing the model at three times its orignal scale on our MakerBot Z-18.
The Dune Queen has lots of overhangs so we'll need to use Support Material during printing. Meshmixer's Support Material tool that is great for pre-generating supports for complex models like this one.
Meshmixer supports save me from having to use MakerBot's more haphazard waffle style supports. They fine for most things, but on this model it would have left me a nightmare of fluff and splinters to remove.
3D Printing the Model
We're going to print this model on the MakerBot Z-18, our shop's primary workhorse for large and elaborate models. IIt's a temperamental beast, but over the years i've dialed in a profile of settings that work well.
Today's settings will be:
The Final 3D Print took 46.5 hours, and came out well despite some minor failure in the support structure.
Finishing and Painting the Model
Were going to put a straightforward finish of layered dry brushing on Dune Queen. Before we can start painting, we need to clean up the layer lines and artifacts from printing and sand the areas where we want a polished finish.
Removing the Support Material
First we'll use a pair of needle nose pliers to break the support material away from the model.
This isn't an elegant process so with a model like this one some small bits are sure to get broken off. Keep a bottle of super glue handy.
TIP: Flush Cutters are great for cutting supports away from those hard to reach areas.
Gap Filling Modeling Putty
We're going to use modeling putty to fill in the layer lines on the face, chest orb, and in the inset spheres on the headdress. Modeling Putty is a fast setting single part plastic filler that fills small imperfections. After it drying, it's easy to sand and create a smooth surface for a mirror-like finish. The solvents in the putty are fairly nasty, so wear gloves and work in a well ventilated space.
Spread the modeling putty on with a fine tool or gloved finger. We are only going to apply the putty in area's we want to be glassy smooth, the face, orbs and headdress depressions.
Tip: Modeling Putty is a fairly expensive specialized product for filling gaps in plastic models. It comes in small tubes for $8-$10... Or you can buy a giant tube of Bondo Glazing & Spot Putty from any hardware or auto store for $3. It's essentially the same stuff.
With the Modeling putty dry, we're ready for the first sanding. We are going to lightly wet sanding the whole model with 400 grit sandpaper.
For most of the model, this sanding is just to knock down any ugly high spots and leftover bits of support material. Were going to spend extra time sanding the face and orbs to make sure they become one smooth surface.
Tip: Wet sanding sound much fancier then it is. The small amount of water just keeps the dust from clogging the grit on the sandpaper and the friction of the sanding from melting the PLA. Dip the paper it water occasionally to keep everthing damp, and have a towel handy to contain the inevitable mess.
Filler Primer Spray Paint
Filler Primer is a Special type of spray paint designed to fill small imperfections with a voluminous sandable layer. It needs to be applied in light layers just like all other spray paints. If you spray on too much at once, it turns into a gooey mess that takes forever to dry.
After we have built up a few layers of Filler Primer, It's time for more wet sanding. This time we're going to use 800 grit sandpaper. We make sure to work over the whole surface of the model, but most of our effort goes into the Face and Orbs where we are looking for that glassy smooth surface.
Tip: Filler Primer isn't a miracle product that will magically turn a bad print into a good one. It just helps make layer lines on good print a little less obvious to the eye.
Base Coat of Black Spray Paint
We need a base coat of color to back up the dry brush effect that will build up the color on the model. In this case, we'll use a nice solid coat of flat black.
Dry Brushing Color onto the Model
Dry brushing is a very easy technique to learn and creates great looking results with with a minimum of time investment. The name basically describes the technique. After filling the paintbrush with a small amount of color, run it back and for over paper to take most of the moisture out of the paint. Now take the brush with mostly dry paint and lightly run it over the top of the model's surface, depositing small amounts of color on the model's high spots.
For the Dune Queen, I am using two layers of color. First a heavy dry brushing of green acrylic paint. Then a follow-up dusting of white on the high spots. The black and green work together to create depth in the model, and the white bring out the details of the texturing.