Whether they’re Oscar statuettes, youth sports participation awards or anything in between, we tend
to think of trophies as shiny metallic objects. But there’s no rule that says
they have to be gleaming silver or gold, especially if you’re making them with
a 3D printer.
In Part 1 of this post, we
shared methods for giving 3D-printed trophies a finish that looks like chrome
plating. Now, let’s explore a different approach to post-processing for plastic
pieces made with FDM (fused deposition modeling) printers.
After successfully completing
our Cisco trophy, we decided to create small trophies for each member of the
winning team at our annual fundraising golf tournament. Our Director of
Instruction, Tom Meeks, came up with as design featuring a golf ball atop a
cylindrical base. And instead of the standard metal-plated finish, Tom wanted
the ball to be white – like a real golf ball – and the base to look like
wood.
Finished trophies for YouthQuest's golf tournament |
We had initially ruled out
using FDM machines for the project because, even when they’re set for the
finest detail, the printing process always leaves visible striations as layers
of melted filament are stacked up. We wanted to create plastic parts with
smooth surfaces – and do it with a minimum amount of effort.
One popular method is sanding
the piece and brushing on an epoxy product such as XTC-3D or, for plastics like
ABS, Acetone. But that can be time-consuming, mixing the epoxy can be messy and
Acetone is potentially dangerous to you and your print if you’re not careful.
Tom’s search for a better
solution led him to discover Polymaker. The company makes a PVB filament called
PolySmooth, which prints like PLA, but can be smoothed with ethanol or
isopropyl alcohol. Post-processing is done by putting prints in the Polysher, a
device that generates an alcohol mist inside a see-through tank. Print layer
lines virtually disappear, leaving a surface that looks polished – exactly what
we wanted for our “golf ball.”
Ball after smoothing in Polysher |
To print the base, we
could have used any number of filaments made with a mixture of wood and thermoplastic,
but they tend to cause extruder clogs. Instead we went with Polymaker’s
PolyWood, which doesn’t contain any wood particles but looks and feels much
like genuine wood, and can be textured and stained just like the real thing.
Trophy base made of PolyWood before staining |
Having filament that’s
affected by alcohol also opens up some interesting possibilities for adding colors to 3D printed pieces in post-processing. Tom had been experimenting with
the Craftwell eBrush, an electric airbrushing system that uses alcohol-based color
makers, before he learned about PolySmooth filament. He’s planning to have our
advanced 3D ThinkLink students try
using the eBrush on PolySmooth parts to see what kind of results they can
produce during our next Immersion Lab Week.