diff --git a/docs/1_documentation.md b/docs/1_documentation.md
index 18a9289..e1d8c8b 100644
--- a/docs/1_documentation.md
+++ b/docs/1_documentation.md
@@ -2,9 +2,37 @@
 
 ## Contents list
 
+- [`Bill of Materials`](2_BOM.md)
+- [`Build Guide`](3_build_guide.md)
+- [OpenClino](#openclino)
+  - [Contents list](#contents-list)
+  - [Notation](#notation)
+  - [Code](#code)
+
+## Design requirements
+
+Clinostats are usually used in biology for plants, cell cultures, and small animals such as fish.
+
+1 - OpenClino shall be robust to failures to not harm the animals or samples. 
+2 - OpenClino should operate in hot/humid environments such as incubators.
+
+3 - OpenClino should operate as a clinostat or RPM.
+
+At the moment it is a work in progress. I'm not an electrical engineer so this is 12v.
+Be careful with your electronics. 
+At the moment it functions as a clino but not an RPM. The motors can't start a new direction or speed independently.
+
+## Code
+
+The code is work in progress, it requires the following:
+ - control multiple motors.
+ - acceleration.
+ - docs.
+
 ## Notation
+TODO 
 
-Definitions
+Definitions:
 motor_pulley
 x_pulley
 y_pulley
@@ -15,12 +43,3 @@ y_guide
 motor mount
 motor enclosure
 which is x and y
-
-## Code
-
-The code is work in progress, it requires the following:
- - control multiple motors
- - acceleration
- - docstrings
-
-
diff --git a/docs/2_BOM.md b/docs/2_BOM.md
index 6729ce5..526e4a0 100644
--- a/docs/2_BOM.md
+++ b/docs/2_BOM.md
@@ -2,32 +2,36 @@
 
 ## To Buy
 
-- #1 x Arduino nano
-- #2 x nema 17 motors
-- #2 x stepper motor controllers (A4988)
-- #2 x 180mm GT2 belts
-- #1 x 500mm GT2 belt
-- #2 x stepper motor pulleys
-- #1 x 1mx20mmx20mm aluminium extrusion
-- #12 x 8mm (ID) skateboard bearings
+Electronics
+- #1 x An arduino of your choice.
+- #2 x Nema 17 motors @ 0.42Nm.
+- #2 x stepper motor controllers (A4988).
 
 Hardware
-- #4 x m8 by 60mm hex bolts
-- #2 x m8 by 100mm hex bolts
-- #8 x m3 alan bolts
-- #12 x m5 alan bolts
+- #2 x 200mm GT2 belts. 6mm width.
+- #1 x 500mm GT2 belt. 6mm width.
+- #2 x 16 tooth stepper motor timing pulleys.
+- #1 x 1mx20mmx20mm aluminium extrusion. You will have to cut this in half.
+- #12 x 8mm (ID) 22mm (OD) skateboard bearings.
+
+Bolts.
+- #4 x m8 by 60mm hex bolts.
+- #2 x m8 by 100mm hex bolts.
+- #8 x m3 by 12mm alan bolts.
+- #12 x m5 by 16mm alan bolts.
+- #13 x M8 washers (8mm ID, 16mm OD).
 
 - 1KG of your printing filament of choice.
 
 ## To Print
 
-- 2 x m_enclosure
-- 2 x m_mounts
-- x_body
-- x_pulley
-- y_body
-- m2y_pulley
-- y_turn
-- 2 x y_turn_pulley
-- y_guide
-- y_pulley
\ No newline at end of file
+- #2 x m_enclosure
+- #2 x m_mounts
+- #1 x x_body
+- #1 x x_pulley
+- #1 x y_body
+- #1 x m2y_pulley
+- #1 x y_turn
+- #2 x y_turn_pulley
+- #1 x y_guide
+- #1 x y_pulley
\ No newline at end of file
diff --git a/docs/3_build_guide.md b/docs/3_build_guide.md
index fe93260..74132fd 100644
--- a/docs/3_build_guide.md
+++ b/docs/3_build_guide.md
@@ -172,7 +172,7 @@ We will build the sub assemblies: y_turn, bodies, and the base, and the final st
 
 <img src="images/build_guide/6_finito.jpg" alt="combine" width="400"/>
 
-Make sure every pulley and axis rotates smoothly. If there is friction anywhere you might have to loosen the bolts or sand down interference.
+Make sure every pulley and axis rotates smoothly. If there is friction anywhere you might have to loosen the bolts or sand down interference from your prints.
 
 ## Electronics
 
diff --git a/docs/images/bearing.jpg b/docs/images/bearing.jpg
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diff --git a/docs/images/stepper motor diagram.jpg b/docs/images/stepper motor diagram.jpg
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