Instructions for the Prusa i3 3d printer

hi there,

i am looking to build this 3d printer:

I want to get the parts and stuff but I’m hesitating a little because I am unable to find the instructions on how to put it together.

Does anyone know where the instructions are or what to reference to put this 3d printer together?

And has anyone been able to get cheaper prices than what is found on amazon or on the shop link on the parts page.


I’m not sure if you have any 3D printer experience, unfortunately this isn’t the best “1st printer”, If you are looking for a (in my oppinion, perfect) 1st printer, the prusa I3 is amazing especially for the price, . Mine is very simple to build if you have used a few printers and have a basic understanding, Twelepro has put up a ton of his build pics here, I also have some pics on the project page,

In your email you asked about the differences between the printer and the CNC. The printer is just a quick project I put up and it is just a printer, it does have a quick change head but no attachments have been made, yet. I made it because I was not happy with the inexpensive options out there, and needed a handful of printers to make cnc parts.

The cnc is a whole different animal, it CAN print but I wouldn’t really call it a printer…I guess, not really sure. The cnc is a great printer if 200mmx200mm is not big enough for you.

If that didn’t help maybe a little info on what you plan on doing with it?

As for prices, you can get everything cheaper. Amazon is just easy and fast.

right now i just dont have a ton of money to wrap up in a 3d printer. i was thinking of a budget of 400 to 500 dollars.

basically just want to learn and practice 3d printing. i like how the cnc could do other things later on but it would be too big right now for the limited space i have.

im an engineer student and would like to make stuff for projects and personal enjoyment and dont need a large build area.

a friend had built your cnc and he uses it alot. he mentioned building the 3d printer you made as my first but after reading your post about it it seemed like you were 100% happy with it and i just want a good first printer so i can enjoy making things.

is there another diy printer you would suggest instead of yours that would be a good first printer or would you go with the prusa i3 kit you linked to?

whatever suggestions or help you can give a first time 3d printerer i would greatly appreciate it. i have a nasa project im working on and could really use a good 3d printer to make some stuff for it.


Okay, I think we are on the same page now. I must have worded that wrong, I love the printer, I built/designed exactly what I wanted in an inexpensive printer (an modeled it after what I think is a perfect printer, the prusai3). I made it as universal as possible so if you can scrounge some common reprap bits it can be really cheap. You’ll see most of the builds are actually rebuilds of crappy machines into the MP3DP. You might have seen some of my other posts, and yes, after running 3 of them for months 24/7 I do want to change some things. I am actually printing round 2 of some new prototype parts. You’ll see when you graduate, every single thing you do work on has compromises and constraints, one is always time. If/when the new printer is done most of the parts will fit, as of right now a few dollars in screws is the only hardware/electronics difference besides the frame and printed parts of course.

In summary, haha, If your friend has built the MPCNC he can easily help you if you get stuck on printer assembly it is easier to build. I like it, give it a try, if you don’t like it The parts will fit other kits. Since your buddy has a cnc he can even cut you a frame, save you some money (allthough to be honest I buy mine from twelvepro now because his are cheaper than I can buy the raw material for and I don’t have to spend hours cutting parts).


so i got most of the parts in and started assembling the milled/3d printed printer from your site, but i have a few questions.

  1. you have listed 16 screws to be used on the steppers but from the pics and the parts i have i will only be using 12. where am i miscounting? where are the extra screws used.

  2. is the zip ties the most effcient way to connect the belt on the printer?

  3. how tight should the belt be on the machine?

  4. i bought the sd card reader device off your site and was wondering does using it have any limitations compared to using a laptop to run the 3d printer?

  5. what is the best slicer program you use for the milled/3d printer? i have looked at a few to try but they mention to use the one that the person or company suggests goes with their product for best results.

so far the assembly is easy and without trouble. just waiting on a few parts to contine and finish.

thanks again for your help. have a good one.

I’ll take a stab at these questions!

  1. Lets see, z axis steppers (there are 2 of them) each use 3 screws, x axis uses 3 and y axis uses 3 so I believe you are correct, only 12 needed. I have stripped a few so it definitely doesn’t hurt to have a few extra.
  2. I was skeptical about the zip ties to keep tension on the belts but it works really well. I have no plans to change it. Also, I’ve ran my printer for many many hours and the belts haven’t lost any tension so far.
  3. I don’t have my belts very tight at all. Just enough so that you don’t have any slippage on the stepper.
  4. I use a laptop right now, but I’m planning on moving to the SD card. One night I had a print fail because the computer rebooted for windows patches. Also, for long running prints, I don’t want my laptop on the entire time.
  5. I was using Ponterface for troubleshooting/testing in the beginning and then moved onto Repetier-Host. Now I’ve moved on to MatterControl. I really like the interface and it feels like the printer is running better than it did on Repetier. I hear great things about Simplify3d but it’s an extra $100 or so cost for that one.

I agree with Troy.

5-Any software really, they are all pretty good now and they aren’t all that different anymore. I think a cool one for beginners is matter control. I use matter control, simplify, repetier, daily. Each one presents you the information differently. I like repetier the best (used it the longest) but it’s not all that beginner friendly, I do actually like mattercontrol better but there is a setting that it doesn’t have I can’t remember what it is at the moment.

I just found the setting in MatterControl that sends a message to your phone when the print is done. Very cool!

hey ya’ll,

thanks so much for yalls help. i just have a few more questions before i get done building the 3d printer:

  1. is there a better way to connect the belt besides the zip ties? ill use the zip ties for now but didnt know if there is somehting you can buy that can connect the belt better.

  2. i think i overlooked the need for 4 drivers and the kits for the board on the parts list only had 3 on it. so if i buy the 4th driver, where do i connect it at on the board?

  3. the quick connectors on the site for the steppers, they are just made for the steppers to quick connect? is there other quick connects you would suggest to make the wiring easier?

  4. best wire to connect evertyhing else up( like power supply to board and such)?