Upgrading a Prusa i3

If you have been involved in the 3D printing world since its inception then at some point you will have come across Josef Prusa and the original i3.

Josef created argueably the first open source 3D printer that pretty much anyone with instructions could make from freely available materials back in 2009.

So there are many instructables on how to make an i3 , so I will not go into that unless someone asks me to do so , Instead I will discuss some of its bad points (well not bad points but things that can be improved and how to do it).

So lets make a list of items that can be improved

The Frame – Upgrading a Prusa

Made from threaded rod and smooth rods with a few 3d printed parts an example is below

Smooth rod is 8mm diameter with LM8uu bearings used as a transport system , the threaded rod is used to stabilise the frame hence the large number of nuts and washer.

First improvement would be to change the outer nuts to nyloc nuts which will enable the frame not to start to shake apart,

The nylon inside of the nut stops the movement of the nut as the printer does its magic , helps with anti vibration. This is a very simple but effective upgrade.

The next useful upgrade would be to attach the frame to a baseboard to enable less vibration and make it more stable , so you could print the following

So using a baseboard is also useful for transporting your printer.

So some more frame extras

Print two of each of the following and assemble to look like this

So lets talk about the Z axis – 2 motors , 2 smooth rods , 2 threaded rods floating about in mid air so to speak

So print these and purchase some bearings and replace the top rod connectors – once again this is for stability – the more stable the axis and machine are the more accurate your prints will be.

That makes a good start to ensure your printer becomes very stable.

Y axis belt tensioner – Upgrading a Prusa

Whilst the original is just about adequate it is worth printing the update model which gives a little more solidity and tension.

On reflection the bolt that is screwed in from the back cuts its own thread into the plastic which over time could strip the plastic away and become loose , what you could do is put a brass threaded insert into the back for the bolt to screw into.

X axis belt tensioner – Upgrading a Prusa

The standard way that comes with the original i3 works pretty well but an extra bit of tension works – the simplest way is to download and print this upgrade which is one of my favorites

Z axis anti-backlash – Upgrading a Prusa

This is a completely new ball game , I would suggest that you change the 5mm threaded rods to 8mm threaded rods with the corresponding ball nuts – If you go this route you will have to reprint new x axis left and right sides as below.

Having the M8 threaded rod will improve stability , but what you have to remember is that you have to re calculate your settings eg TPI (threads pre inch – how many turns it takes to move an inch)

Auto bed leveller – Upgrading a Prusa

This is a nice to have if you have had to go through re levelling your print bed every so many prints

I favour the inductive method in which a sensor is triggered by aluminium on you bed and automatically changes your printer settings to suit.You need to print out a part to hold the sensor and do a bit of wiring in of a couple of resistors.A fairly simple upgrade if you take your time.

I will do another post on the various types of sensors and the different ways of setting them up.

Fans – Upgrading a Prusa

A word or two about these little fellows , Cooling the filament before the filament arrives at the heater block seems to be crucial now , especially since the arrival of all of the exotic filaments,Also cooling the prints also is very helpful for achieving good results , this is a subject for another post.

Extruders – Upgrading a Prusa

When the first i3 came into existence there was the J head & Wades extruder now there are many others , Bowden,direct drive multi print heads – consequently the amount of information is vast and yes probably the subject of another post.