P3Steel – Prusa i3 3mm Steel Laser cut (aka Leonardo)

Author: irobri, published on 2013-09-27

Click this button to get the 3D model


This is a remix of twelvepros redesign of Josef Prusa i3, the printer was built in April 2013, decided after attending a local Maker show in Zaragoza, Spain.
I liked the Prusa i3 single plate design but then I saw twelvepros and thought it was a better option, I just wanted to get rid of the threaded rods y axis mount and adjustments.

Although this is not based on it, I want to mention S. Graber and his Graber i3, he came out also with a very nice redesign of twelvepros of a complete laser cut i3.

The printer is made of 3mm laser cut steel since I wanted it to be sturdy and I had a laser cutting machine available at work:


  • Steel is 10 times cheaper than aluminium
  • Laser cutting steel is easier and cheaper than cutting aluminium
  • Steel is stronger than aluminium


  • Steel is 3 times heavier than aluminium

The design is for 3mm thickness steel and with lots of carvings to reduce weight. All square holes and tabs have special rounded corners for accommodating corresponding parts and give a very good fit between plates. No threading required.

I hope someone finds this design usefull.

(Leonardo is just the name of my printer, here in our local reprap group we give names to our printers…http://www.reprap.org/wiki/Proyecto_Clone_Wars)

Over 50 people have recently made this printer in Spain, they have been working a lot and they have created a wiki (thank you guys!) for this printer model which they have named P3Steel, the wiki has a lot of helpfull info for building the printer and it even has an animation of the assembly of the printer, I post the link because I am sure it will help anyone that decides to build it, the wiki is both in English and Spanish: http://reprap.org/wiki/P3Steel

Since the number of made printers is increasing exponentially and now everyone knows the printer as the P3Steel I just updated the name to the new one!


I have included some photos to help the assembly and also some 3D assemblies (just discovered Google Sketchup…)

Version 1.2: Leonardo original printer, the one I made.
Version 2.0: After some requests of a spanish group buiding around 30 printers I have modified the bed, now it holds with 4 LM8UU instead of 3 and it has also a system to level with 3 points intead of the original 4, it should be easier with this new design. I kept the original 4 points also just in case someone still wants to use them. I included in the gallery some 3Ds of the new bed. The rest of the printer is exactly the same as version 1.2

Check the wiki! http://reprap.org/wiki/P3Steel

Everything snaps together and hold with a lot of M3x12 screws (mainly), I also used nylon self locking nuts to prevent future problems due to vibration.

The printer uses 8mm chromed smooth rods (Z axis: 2 x 320mm, Y axis: 2 x 341mm and X axis: 2 x 375mm) and only two M5 threaded rods (295mm aprox each since depends on motor coupling and if you want some stick out through the top) for the Z-.axis, printed parts required came from a standard Prusa i3, you only need the parts for the x-axis assembly and the extruder.

The printer structure is assembled quite fast and needs no adjustments. The electronics are installed in either side of the frame, horizontally, holes provided are for an arduino mega and ramps 1.4.
Motors are NEMA 17, GT2 pulleys, LM8UU and 608zz bearings
Hotend is budas type. MK2b hotbed.

License: Creative Commons – Attribution – Non-Commercial

Tags: 3D, 3D_Printer, 3mm, Cut, i3, iteration, Laser, Laser_cut, Leonardo, P3Steel, Printer, Prusa, Prusa_i3, Prusa_iteration_3, Steel, twelvepro