My first 3D printer - the Geeetech i3 Pro B (Prusa Clone)

My first 3D printer - the Geeetech i3 Pro B (Prusa Clone)

Back in the day...

When I was a kid (back in the 80's), I used to come home from school and watch a great TV show about future technologies. I don't remember the name of the show, but it had some interesting ideas. One of those ideas was this notion of having your own miniature manufacturing machine in your home that could make anything with plastic. I had seen my first 3D printer, and I've wanted one since then.

The printer

Geeetech i3 Pro B MK8 (Prusa Clone)
Geeetech i3 Pro B MK8 (Prusa Clone)

A few weeks ago, I received my first 3D printer in the mail. I ordered the Geeetech I3 Pro B from ebay.

I decided to go with this printer based off of a few comments that were made in this YouTube video from "Design. Prototype. Test.":

Update: I have sold my Geeetech and purchased a Creality Ender 3 Pro. It was a little more expensive, but it was easier to assemble (45 minutes versus 6 hours for the Geeetech). It also printed right out of the box after I leveled the bed. However, I have to admit that assembling the Geeetech was a lot of fun, something that I missed when putting together the Ender 3.


When it arrived, I got started putting it together. There was no assembly instruction manual included with the printer, but there was a very thorough parts list and a link to a PDF containing the assembly instructions. Within the PDF, there were links to YouTube videos for many of the assembly steps, so assembly was easy (to me).

The printer shipping box

The printer shipping box layer 2

The printer shipping box layer 3

This kit isn't for the beginner. It requires a lot of thinking and problem solving. If you want a printer that you can just take out of the box and start printing after a few minor adjustments, you'll want to spend a bit more money and go with a Creality CR-10 or other such commercial printer (like the Ender 3). This kit was less than $200, but you'll spend the difference in the time it takes to get it up and running effectively. It's a trade off between time and money. I really enjoy tricky and puzzling endeavors, so this was the perfect kit for me.

It took me about 5-6 hours to put it together as I went slowly to make sure I didn't overlook anything. There's a lot of information about this printer on the web, but you have to search Google and Facebook to find it. Once located, there are many people who can help you with your assembly if you should run into any problems. I ran into a few beginner issues that I quickly solved by simply searching for the solution on YouTube or Google.

There were some mechanical issues that I ran into. One interesting problem required the use of fire. One of the drive belt pulley housings was too tight for the wheel to move freely, so I had to apply outward pressure on one side while applying heat to the joint. When it cooled, the pulley would move freely between the two edges. Here's a picture of how I had to hold it with a pair of pliers while applying the heat:

Engineering at its finest
Engineering at its finest

Assembling the printer was very rewarding. It was really neat to see it come together as I progressed through the steps.

The printer base with bed
The printer base with bed

Fan assembly
Fan assembly

Post-build learning

After I had the printer built, I started down the path of actually learning how to use it. I had already watched quite a few videos about 3D printing, but I wasn't sure exactly how to get started.

One of the resources I used was the Geeetech i3 Wiki.

Here's the basic workflow that I discovered:

  • Find a 3D model to print - I decided to use a 20mm calibration cube as my first print because it was big enough to have some substance, but small enough to manage.
  • Download the software - You'll need at least two pieces of software in order to print your model: a Slicer and a printer host (unless you're using the SD card approach - which I'm not). I downloaded the Repetier Host from Geeetech that is made specifically for this printer. This includes the other piece of software that you'll need: a Slicer. However, I never could get the included slicer (Slic3r) to work, so I ended up downloading the latest version of Ultimaker Cura. Cura worked right away for me after an hour or so of failed prints using Slic3r.

The slicer software will convert the 3D model into G-Code, which is the code used by the printer to know the x, y, z, and extruder coordinates to use when printing an object. There are a lot of settings to work with to get your prints working. Each printer is different and each printer/filament combination will require adjustments to temperatures.

My filament was Inland 1.75mm black filament at $20.99 for a kilogram (it's now priced at $16.99). It has a recommended temperature range of 205°-225° Celsius. I've found that running it at 216° is what works best for my printer. I keep my print bed heated to 60° (all future temperatures will be expressed as Celsius).


Here is the evolution of my first four prints.

First prints

Top left: My first attempt at using Slic3r. As you can see, I had no luck with this. I didn't really know what I was doing and the Slic3r is not inuitive.

I got a little better and had better results with the top right "cube".

Bottom left: This was my first print using the Cura slicer. Still not good, but at least I got a whole cube this time.

Bottom right: my second print with Cura (and fourth overall print). I had better layer adhesion because I adjusted my extruder temp from 200° to 210° (I had not yet experimented with the temperatures to find the target temp for this filament). I got a good cube, but the top of it was rough because I was not using a part cooling fan.

Expanding the printer

That leads me to the next topic: Expansion. I bought this printer because it is a great candidate for upgrading. It's easy to print replacement parts and parts to improve the print performance of the printer. The first part I wanted to print was a part cooling fan. This allows you to print longer bridges (where the printer prints into "thin air" between two edges). It makes much nicer edges, as well.

First fan housing
First fan housing

After many failed attempts at a perfect part cooling fan housing, I was able to find the perfect one by contributing to the "Design, Prototype, Test" Patreon campaign. As a contributor, he gives you access to designs that he's personally created for various 3D printers that he owns. He's created a few parts for the Geeetech i3 Pro B as well as a custom firmware upgrade that adds support for a sensor that allows for auto bed leveling.

Part cooling makes a difference
Part cooling makes a difference. The cube on the left was printed with the part cooling fan attached. The one on the right had no part cooling. As you can see, the bridges of the top did not print correctly and the plastic dropped down into the cube on the right.

Here's a fan cover that I printed:

Fan cover

Bed leveling

The print bed must be perfectly level before starting to print. That's the main issue I've had so far. By level, I don't mean putting a level on the bed and adjusting it. It must be level relative to the X and Y axes. Bed leveling is an involved process and it's hard to get it right. It's probably my least favorite task, but every printer owner has to do it.

Bed adhesion

Once the bed is level and the temperature is correct, the next thing to manage is bed adhesion. This is the ability of your print to stay attached to the bed while printing. The first layer is the most critical layer. I've had most of my prints fail on the first layer. Many people use different surfaces to print on, but I've had good luck just printing onto the glass surface of my printer without the need for glue stick or hair spray. I have had to use a brim (a single layer of plastic about 8mm wide that attaches to the item much like the brim of a hat).

Z-Axis Banding

Perhaps the biggest problem after first layer adhesion has been z-axis banding. That's when there are visible bands along the z axis on the print. I printed some specialized adapters that modify the printer to eliminate most of the banding issues, but I still have a major issue where my prints are showing major weakness at about 50mm high. It is visible below the white film on the head of the Darth Buddha figure shown here (the white film is glue residue from where I had to glue the head back on):

Darth Buddha

Darth Buddha in Cura


One of the main reasons I wanted to get a 3D printer was to print enclosures for my electronics projects. I was able to find a great enclosure for my Mojo FPGA. It printed out in two parts and used standard M3 screws and nuts.

Mojo Case 1

I was still having temperature issues with my extruder when I printed this, so the first few layers didn't extrude properly, giving me some imperfections in the top layers. However, I am pretty happy with how this turned out overall.

Mojo Case 2
The Mojo now has a home

Custom Items

Another exciting aspect of 3D printing is the idea that I can make my own items. I needed a coat hook for my cubicle at work, so I measured out the space. I came home and accessed Tinkercad to create my first item for 3D printing. Version one of my coat hook was too big and a bit on the ugly side. So, I remeasured using digital calipers. Version 2 was much nicer looking and fits the space perfectly. It even holds my coat!

Coat Hook plan v1

Coat Hook v1 (ugggly)

Coat Hook plan v2

Coat Hook v2 - Perfect!

Coat Hook v2


This has been an exciting journey for me. I've really enjoyed learning about 3D printing and assembling my own printer from just a big pile of parts. It's very satisfying to see it spitting out usable objects. While frustrating at times, the hobby has been an overall joy. I highly recommend 3D printing to anyone with a creative spirit that doesn't mind a little bit of a challenge. The rewards are there.

I leave you with "Darth Buddha"

An hour of live 3D printing of part of the Darth Buddha figure