X-Git-Url: http://challenge-bot.com/repos/?a=blobdiff_plain;f=curriculum%2Fchallenge-bot.scm;h=c076dd9df6cf04827988b71e67538b56f21c7c30;hb=85fae63f5c8137998cbce03e2e17ccd919f2cae9;hp=1ae84fda5749200cd3f2468639b0c9db87faa513;hpb=ca8e4428bad920b3941c1a37d63d823f8046eb12;p=challenge-bot

diff --git a/curriculum/challenge-bot.scm b/curriculum/challenge-bot.scm
index 1ae84fd..c076dd9 100644
--- a/curriculum/challenge-bot.scm
+++ b/curriculum/challenge-bot.scm
@@ -37,17 +37,29 @@
                   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"))))
+     (p [here's a cross section of a screw in the deck]
+        (figure :legend "screw cross section"
+                (image :file
+                       "arduino-to-deck/screw-cross-section.png"))))
     (subsubsection
      :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.]))
+                smooth part of the bit when they are tightened.])
+     (p (figure
+         :legend "arduino to deck / twist tighten drill teeth"
+         (image :file "arduino-to-deck/2-twist-tighten-drill-teeth.png"))
+        [while holding the drill bit, twist end of the drill to tighten
+               the teeth.
+               make sure that the teeth end up gripping the flat part of
+               the drill bit.]))
     (subsubsection
-     :title [holding drill])
+     :title [holding drill]
+     (p [hold the drill with one hand on the handle and trigger.
+              put the other hand on the orange nozzle, before the
+              black spinning part.]))
     (subsubsection
      :title [arduino placement]
      (p [the arduino should be placed as shown in this picture.]