SERVO 12.2015 19
Builder: Christian Carlberg
eBike brushless direct drive hub
Custom rims to interface with motors
Builder: Terry Ewert
4 Astroflight 90 motors
Victor HV 48V ESC
Whyachi TWA69 gearboxes
Whyachi 3. 5" wheels
Zippy 5S LiPo batteries, 2 series packs
Photo courtesy of BattleBots™. Photo courtesy of Terry Ewert.
Photos courtesy of Christian Carlberg.
PARTS IS PARTS:
Screws: Keeping It Together
● by Mike Jeffries
Picking the right screw or bolt can be an important decision you make early in your build.
There are several elements to consider
when selecting your hardware for a
Different types of screws are
meant for different applications.
Within many screw types, there are
multiple head styles that have their
own pros and cons. Within the head
styles, there are often multiple drive
options to consider as well.
One element of fastener selection
that applies across the board is that
you should minimize the number of
different fasteners you are using in
During an event, not having to
hunt for the right screw can save
anywhere from a few seconds to
several minutes which may well be the
difference between having a working
bot for your next match or throwing
something that’s only half way back
together into the arena.
Wherever possible, use only one
thread count at any specific fastener
size. Using a mix of 10-24 and 10-32
bolts in your bot is a fantastic way to
end up with damaged or destroyed
threads when you’re putting things
back together in a hurry.
If you have to do this, try to use a
different type of head or some other
means of clearly identifying which
thread is used where so you don’t
need to think about it while doing