Project: 3D printer from scratch. Part 1 – The Shoppingcart.

I’ve always wanted a 3D printer, but the pricetag has been so high that I’ve gotten discouraged in the past.

However with the increasing community support of open sourced 3D printers the accessibility and price has dropped significantly if you’re willing to do some manual work.
As this is not an easy task to build a 3D printer, and that it will most likely mostly stand idle I thought it would be good to have a partner in crime. Knowing my brother also wants a 3D printer I approached him and we decided to build one together.

After a period of research I decided to build the RepRap Prusa i3.

The RepRap project (Link) is an open source 3D printer project founded by Dr. Adrian Bowyer. The build area is about 20x20x20 cm or 8x8x8 inches. This enables about 8000cm3 or 8 litre build.

The filament is about 40 USD/1kg which allows for a ton of prints.

The finished product should look something like this, but with an LCD display and SD card slot to enable standalone printing.

Prusa i3

Before we can begin building we need the parts. With budget in mind I’ve decided to shop the bulk of hardware from Ebay.

Here is the shopping list:


  • 1x Prusa i3 Printed parts (boxed variant)
  • 1x Greg’s JHead Extruder (cold end)
  • 1x M8 hobbed bolt (to pull the filament)
  • 1x J-Head Pre assembled Hotend – 0.3mm nozzle – 1.75mm filament (includes thermistor and resistor)
  • 1x HotEnd Aluminum mount plate for J-Head
  • 1x HeatBed mk2
  • 1x Aluminum Bed mount plate
  • 1x 10k ohm thermistor
  • 1x red 3mm LED
  • 1x Borosilicate glass
  • 5x Nema 17 stepper motor (1.8° stepping angle)
  • 10x LM8UU linear ball bearing
  • 2x 5x5mm coupling (D20L25)
  • 2x GT2 5mm pulley
  • 2m GT2 timing belt
  • 1x LCD 2004 controller
  • 1x Arduino Mega 2560
  • 1x RAMPS 1.4 shield
  • 5x A4988 stepper driver + heatsinks
  • 3x Mechanical endstop switches
  • 1x 624 ball bearing
  • 4x 608 ball bearing


I also bought various cables, connectors and metal clamps, 40mm fans, but these do not need to be defined.

Cost: 420 USD included shipping. This comes out at around 2700 sek.

Next we need to buy material for the frame which I will aquire from the local hardware store.

We need:


  • Wood/chipboard to build the frame.
  • Centerless smooth metal rods
  • Threaded metal rods
  • A ton of nuts
  • Power supply (Any old ATX PSU should suffice)
  • Black paint for the frame


For build instructions there is a great unity 3d model build instruction to be found.

To be continued…


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