My goal was to build a cheap and inexpensive 3D Printer for less than 100 Dollar/Euro

What are the features of the Poor Man's 3D Printer ?

- Fused deposition modeling ABS/PLA

- Heat bed

- use of open source firmware, modified version of Tonokip

- free host software, Repetier-Host

- bowden-extruder

- max. build size 40mm x 40mm x 40mm

- resolution 0.08mm

Step 1: Parts

Parts i bought:

- Arduino Board Mega 2560 (on ebay from china): 10 Euro

- 2 pcs. Stackable Motor Driver Shield L293D 6 Euro

- Hotend MK7 MK8 noozle 0,4mm+thermistor+cartridge 20 Euro

- PTFE Tube 4 x 2mm & 2 pcs. 1/8" BSP 6 Euro

- Fan 30mm x 30mm 2 Euro

- MOSFETs,resistors,caps,LEDs,thermistor 5 Euro

Recyled PC/printer part:

- 4 pcs. DVD/Blu-ray drives, with stepper motors ! old cd drives can't be used because they work with dc-motors

- old PC power supply, 12V/5A and 5V/2A are required

- stepper motor nema17-like from old printer for extruder

- i use a modified gear (see pictures) from an old hp printer for the bowden-extruder, optional you could get an airtripper extruder for about 25 Euro

Things that every hobbyist has in his garage :-)

- many screws, nuts and washers M3,M4,M5

- lots of wires

- aluminium-sheet for the frame, you can also use wood

- some alu/metal profiles, see pictures

Step 2: Pictures From Building the Chassis

Step 3: Endstops

use endstops from dvd drive !

Step 4: Counterweights

I had to made counterweights for the z-axis because the x- dvd drive + Hotend are too heavy for the small steppers

The counterweight is simply connected through a cord and a pulley with the drive.

The weight of one counterweight = weight of (x drive + hotend) /2

Step 5: Extruder

The Extruder was build of a gear of an old hp printer deskjet 300. I remove the original stepper (too weak) and

replace it with a bigger one, i find two of them in an epson stylus color 600.

The shaft was shorten and milled grooves with a dremel, then a metal gearwheel was placed near the shaft.

The gearwheel has one groove too.

Step 6: Hotend

The Hotend is a MK7/MK8 i found on ebay.

i cut some aluminium plates for a better cooling and place a small fan beside

the bigger alu plate above separates the hotend from the BSP fitting via two small screws

Step 7: Heat Bed

the bed is heated by two parallel resistors 22R/7W/axial and reaches 110°C

Step 8: Schematic

I uploaded a hand drawn schematic, feel free to comment/ask questions.

In the picture you can see how to modify the second shield, cut the connector pins D12 and D7,

bridge D12 with D13 and D2 with D7, now the mega can talk with the shields separatly

Schematic_Poor_3D.pdf
Download

Step 9: Firmware/Software

I use Tonokip in a modified version and added Adafruit Motor shield library also modified to use 2 shields.

The Software i use is Repetier Host

See Settings.zip for Repetier-Host and slic3r settings

Step 10: Results

here you can see the first results before/after calibration and some final changes in the firmware, the cube was printed with 1.75mm ABS filament, the edge length in the gcode is 10mm the final result 10.06mm !!!

Step 11: First Update

I change the driver board to ramps 1.4 with A4988 Stepper driver because they have become very cheap on ebay.

( board + 4 stepper drivers about 20$ incl. shipping)

I have supplied the x/y/z steppers with 8 Volt, 12 Volt is to much for those tiny things, with only 5 Volt the drivers won't work. i also limit the current to 300mA (with the poti at drivers)

Here are my results with using Marlin as Firmware.

I uploaded my configuration file from Marlin and also the slicr settings.