show how to insert drill bit

[challenge-bot] / curriculum / challenge-bot.scm

diff --git a/curriculum/challenge-bot.scm b/curriculum/challenge-bot.scm
index 2284e0e24a4be0b49c809d3ee24b41fe42b1bbc3..1ae84fda5749200cd3f2468639b0c9db87faa513 100644 (file)
--- a/curriculum/challenge-bot.scm
+++ b/curriculum/challenge-bot.scm
@@ -31,12 +31,21 @@
                   this means the hole needs to be big enough for the
                   screw body to fit through.
                   we want the screw to stay put once it's in place.
                   this means the hole needs to be big enough for the
                   screw body to fit through.
                   we want the screw to stay put once it's in place.

-                  the threads of the screw will grip the edges of the
-                  hole it's going through.])
+                  we also want the drill bit to be smaller than the
+                  diameter of the thread.
+                  the screw was chosen so that the hole on the arduino
+                  was bigger than the body and smaller than the thread.
+                  we will choose the biggest drill bit that fits through
+                  the hole on the arduino.])

      (p [here's a diagram of a screw]
         (figure :legend "screw" (image :file "arduino-to-deck/screw.png"))))
     (subsubsection
      (p [here's a diagram of a screw]
         (figure :legend "screw" (image :file "arduino-to-deck/screw.png"))))
     (subsubsection

-     :title [inserting drill bit])
+     :title [inserting drill bit]
+     (p (figure :legend "arduino to deck / insert bit"
+                (image :file "arduino-to-deck/1-insert-bit.png"))
+        [insert the drill bit into the teeth of the drill.
+                insert it far enough that the teeth will clamp on the
+                smooth part of the bit when they are tightened.]))

     (subsubsection
      :title [holding drill])
     (subsubsection
     (subsubsection
      :title [holding drill])
     (subsubsection