MATERIALS
» PLA filament in silver, black, blue, and gold
Download the free 3D files for printing at
printables.com/model/109816 and follow the
assembly instructions there.
» Magnets, round, 6.3mm×2mm (4)
» Mylar sheet, aluminized sold as a gardening
product or as cheap thermal blankets
» Glue
» Small wood nails, 1.25mm diameter
TOOLS
» 3D printer
» Tinsnips or Dremel for cutting nails
» Drill bit, ⁄" to clean up hinge holes
ways to create new hinges, move the secondary
mirror assembly, and deploy the sunshield.
Then I started CAD design in Fusion 360. First,
I determine the overall size of the model. In this
case, the limiting structures were the hinges
because the very large sunshield parts needed
to fit on my Prusa MK3S printer. I compromised
by scaling the hinges so I could use tiny nails,
instead of filament or printed parts, as the axles.
Next I imported a schematic into Fusion 360,
scaled it to match, and created the basic outlines
of the parts. Then I worked through the model
building the mechanisms. The secondary mirror
assembly required a lot of testing by moving the
parts and adjusting the angles.
A bigger challenge: The left and right boom
arms for the sunshield needed to occupy the
same space when the telescope was folded. I
looked at umbrellas and toy lightsabers, and
settled on making one boom smaller so it could
store itself inside the other (Figure
A
).
After I printed and test-fit the parts, I added
small magnets to hold the primary mirror wings
tight (Figure
B
), as the side hinges turned out to
be too loose.
The sunshield was by far the most challenging
problem. I quickly found that mylar begins to tear
whenever it is cut or punctured. Looking at a tarp,
I remembered that the metal grommets around
the holes are there to prevent the propagation of
tears. I printed some grommets and glued them
on the mylar, and it worked!
The final model measures 40cm (15¾") long
and I’m very happy with how it came out. I can
follow along with all the deployment steps and
reverse them (Figures
C
,
D
,
E
, and
F
).
You can find this and other models I've
designed on Thingiverse, Printables, and
MyMiniFactory, username chemteacher628. I
enjoy contributing to the 3D printing community
since I’ve learned so much from the open source
resources that so many people create. I hope
you’ll build this JWST model and learn as much
as I did, and that maybe it will encourage others
to explore science and engineering.
97
make.co
A
B
C
E
D
F
See more of this project at makezine.com/
go/3DP-JWST, and check out Prusa’s build
video at youtu.be/N_Q_YUDUSLs.
M81_096-97_3DPtelescope_F1.indd 97M81_096-97_3DPtelescope_F1.indd 97 4/11/22 12:10 PM4/11/22 12:10 PM
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