updated how-to

[clinton/wilson.git] / doc / how-to-build.txt

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How to Assemble the Reprap Wilson 3D printer
Written by Martin Rice <mrice411@gmail.com>
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1. Introduction / Overview of components

	A detailed bill of materials with measurements can be found / generated from 
	the wilson-bom.ods spreedsheet in /docs/.  Below is a concise overview of
	the purpose of the mechanical components you will need:

	1.1 Frame Components
		The frame is built from four pieces of 2020 Aluminum extrusion, two 
		threaded rods (M10 is the default), and plastic (RP) parts which 
		are used for joinery (and in some cases also for holding rods described
		in section 1.2 below).  The plastic parts consist of 10 separate parts:
		6 of which hold the extrusions, two of which hold the threaded rods
		(the Y ends), and the final two which join the horizontal (threaded rod)
		section to the upright frame.

	1.2 Motion Control
		The design uses three sets of linear rods (6 total) and four stepper 
		motors for motion control.

		Similarly to earlier reprap designs in the Mendel heritage, the Wilson
		design has a horizontally mounted print bed which is restricted to 
		motion only in the Y-axis (front to back), and a carriage which moves 
		the	extruder along the X-axis (left to right).  The X and Y axis are
		belt driven, by one stepper motor each that is mounted at one end of 
		the respective axis (these are called the "motor ends").  At the 
		opposite end of each axis is an idler bearing which keeps tension on
		each belt (these are called the "idler ends").  

		The entire X-axis assembly is moved along the Z-axis (up and down) by 
		two separate (but identically controlled) motors.
		
		Limit switches located at one end or the other of each axis are used 
		by the printer firmware to "home" the extruder at the beginning of a
		print.  

	1.3 Extruder
		Plastic filament is extruded onto the print surface by a geared extruder
		mounted to the X-axis carriage.  A fifth stepper motor turns a grooved
		bolt (i.e. a hobbed bolt) against which the filament is held firmly by 
		a spring-mounted bearing.  The filament is forced through a heated end
		with a tiny hole (generally 0.5mm or smaller) at a controlled pace to 
		construct the desired object.  A thermistor located at the hot end is
		monitored to maintain the programmed extrusion temperature, which is 
		material dependent but generally around 200 degrees Celsius.

2. Assemble the Y axis (part 1)

2.1	The following parts are used during this step:
	a. The two M10 threaded rods
	b. The Y axis smooth rods
	c. The plastic Y end pieces (2)
	d. The two plastic frame brace supports
	e. 12 M10 nuts and washers
	f. Four linear bearings (LM8UU)

3. Assemble the Frame (part 1)

3.1	The following parts are used during this step:
	a. The two side pieces of 2020 aluminum extrusion (the longer ones, generally)
	b. One of the two horizontal pieces of 2020 aluminum extrusion (the shorter 
	   ones, generally)
	c. 36 T-slot nuts
	d. 28 M5 x 8mm screws
	e. The plastic Z motor holders (2)
	f. The plastic rear frame brackets (2)

4. Mount the Y axis to the frame

4.1	The following parts are used during this step:
	a. The partially-assembled Y axis from step 2.
	b. The partially assembled frame from step 3.
	c. Eight M5 x 8mm screws


5. Assemble the X axis (part 1)

5.1	The following parts are used during this step:
	a. The two plastic X end pieces ("motor" and "idler")
	b. Eight linear bearings (LM8UU)
	c. The two X axis smooth rods

6. Mounting the X axis to the Z axis

7. Assemble the Frame (part 2)