I tend to start with
sketches on Microsoft
PowerPoint. If things look
complex, I’ll model with
cardboard or wood, then
proceed to aluminum or
sheet metal before cutting
expensive titanium or composites. My beetleweight
Fir Darrig went through
many iterations. It started as a BVD
to Fabrication bot, with 1/8”
aluminum free form bent in a vise.
Later, I transferred the shell to paper,
onto posterboard, then to sheet
metal. To bend the titanium, I made
a wood model which was also the
“shoe” for a homemade brake.
Ultimately, this process failed me
when I tried to cold bend the
titanium rather than applying heat,
resulting in a big crack. I wound up
running the sheet metal prototype
with titanium appliqué armor.
My next attempt at using wood
for a design medium came when
I attempted to rebuild my
Lightweight, Chupacabra, after
its shredding by Killerbotic’s 2EZ.
I ripped fir boards down to
1/2” square to simulate aluminum
tubing. With the help of drywall
screws, I modeled the frame around
the components such as motors
and batteries. The model went
to my sponsor’s welding shop,
where I learned another lesson
In an attempt to make a low
clearance bot, I’d cut the pieces very
closely to the maximum possible
dimensions. Unfortunately, I failed to
indicate the “critical dimensions” to
the fabricator, so it came back
unusable for my parts. Slight
tolerance buildups, differences in
material dimensions, and frankly, just
some sloppy welding resulted in a
$200 frame I couldn’t use. Lesson
learned: Build it yourself, or at least
be there when it’s built!
For the next two bots I built,
I skipped the modeling effort.
Our highly successful antweight,
Babe The Blue Bot, moved from
version III to version IV using a
(L-R) Fir Darrig, wood form,
titanium blank partially bent.
Side view of wood form being
used as a bending brake shoe.
direct BVD (actually a dinnertime
conversation from the kids, after
the spanking defeat of III) to a
3D PowerPoint visualization, to
fabrication. To size the pieces, I laid
all components out on the raw
baseplate material, drew around
them with a Sharpie, then cut. This
version worked very well, and it
went from concept to arena with
CAD” of Babe IV.
Chupacaba: High fidelity wood models don’t
necessarily mean an accurate result.
Babe IV, after several fights. Quite a
John Henry, parts mounted directly from
the rough layout.
Frame built directly around the core bot,
no design needed.
Berserk Robotic’s Archon went from high fidelity CAD directly to hardware.
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