This article is intended to be a review as complete as possible of the Geeetech i3 Pro B 3d printer, which is one of the most popular printers in the world, given its low cost and the ease of buying it and getting it delivered in any country from its many resellers.
I will go over its assembly process, general characteristics, known issues, print quality, and the pros and cons.
So, without any further ado, let’s get started!
This printer comes in a DIY kit, unlike the Ender3 which comes partially pre-assembled. That means you will have to assemble the entire printer yourself which can be either entertaining or very frustrating, depending on your skills and your desire to learn.
As a first piece of advice, I would say that the i3 Pro B is not the best printer to get started with in the world of 3d printing, although it is inexpensive and can give good results, it is necessary that you master certain aspects related to the mechanics and electronics of a 3d printer before assembling one of them yourself. Otherwise, it is possible to run into simple problems that someone with some basic-level knowledge can quickly figure out, but you can’t.
Before starting, I must clarify that when I bought the Geeetech i3 Pro B I already had some years of experience in the use and assembly of 3d printers. Due to this, I was able to solve many problems during the assembly of the printer that are not clearly explained in the manuals and video that the company provides to guide users.
Having an idea of what I was doing, it still took me more than 10 hours to put all the parts together (in their correct position, by the way…). Perhaps, with the help of a friend I could have done it in half the time, since looking for the necessary piece in the parts list and identifying it sometimes takes more time than the assembly itself.
This is important to keep in mind, especially if you don’t have a large table at home. Do not use the table where you and your family eat, as it will probably take a day or two to finish the assembly and you will get some very disapproving looks.
The printer comes completely disassembled down to the last screw and wrapped in a large cardboard box. You will need a large space to verify that no parts are missing which can be done with the help of the list provided. In case any parts are missing, Geeetech’s after-sales service is very good and will gladly send the missing parts over to you, although this can be somewhat frustrating if you were excited to get started.
You may replace some screws or washers, but a stepper motor or a control board aren’t things you usually have at home (Those will generally not be missing though).
On the official Geeetech website you can find the assembly manual, which is very helpful but it is much better to follow the video tutorial available on YouTube. It is normal that you get stuck in some steps, since many pieces are similar or are not perfectly labeled in the assembly manual. Again, take it slow and be VERY patient at this point, as you only need to assembly the printer once.
With patience (and a lot of free time), you can have your 3d printer working and won’t need to ever go through the process again. In addition, the complete assembly of this machine will allow you to know in depth each one of its components, which will give you an additional experience that other pre-assembled printers cannot give you.
The i3 Pro B mounts its components on an 8mm thick laser cut acrylic frame held together by heavy duty threaded rods. The dimensional tolerances of its parts are adequate and they tend to generate some friction between them, so it is recommended to use the file provided to wear the joints a little before assembling them. Some users skip this and acrylic tends to break under pressure.
The printer has no printed parts, which is often the weak point of many low-cost Prusa clones. The metal parts are rigid and look very strong.
The X/Y axis belts have their corresponding tensioners, so there is no need to modify the mechanism ever.
The quality of its components is somewhat related to its price: The bearings look low quality and the Z axis brass nuts are a bit loose when mounting. Anyway, once the printer gets assembled it feels stiff. I have a different Prusa i3 clone at home, armed with a steel frame that transmits much more vibrations to its parts than the Geeetech printer.
The control board in this printer is the GT2560, which integrates in a single board all the functionalities of the Arduino Mega + Ramps 1.4 set. The configuration that its firmware brings is adapted to the hardware of the printer, so it does not require any modification such as calibrating the steps of the axis or the extruder. It mounts to one side of the printer, and has a small fan to cool the drivers. As it does not have a case to protect it, it is usually filled with dust that needs to be cleaned frequently.
One point to note is that the printer does not have a layer fan, although the board does have the jack available to place it, and the printer menu allows you to control its speed. Considering that the layer fan is a great help when printing, I think Geeetech could supply it and achieve a more complete 3d printer. As a tip, I suggest that your first piece printed with this machine is a fanduct for a 5015 blower fan.
The printer’s screen is located on top of the acrylic frame and due to this, the filament spool cannot be placed on the frame of the printer. I think it is somewhat uncomfortable and it would be better to have it placed on the front of the machine. If you like modifying your printers, this might be a good idea.
In addition to the printer, a support for the filament spools is included in the kit. To make it stay in place, I fastened it to the table using a wood screw and washer. Of course, it is not a good idea to punch a hole in a table. The downside of this stand is that it is too small, and large spools cannot be fitted. The solution I found is to use an 8mm rod and pass it through the top hole.
Also, since the filament can catch on some moving part of the printer, I printed this part:
This little upgrade allows the filament to be guided and prevents it from tangling.
The extruder provided is an old acquaintance: the MK8. In my case, it is aluminum, but I know people who received the extruder made of plastic. It works very well and there are no jamming problems.
Usually this extruder is used for Bowden type printers, but the i3 Pro B has a direct extrusion system mounted on it. The way it is assembled, there is a gap between the barrel and the extruder sprocket. This means that when printing TPU, the filament can escape through that space and ruin the whole printing process. I use a small piece of PTFE tube to eliminate the gap, but sometimes it gets out.
There are some pieces available on Thingiverse that allow you to solve this issue, but if you only print stiff filaments, there is no need to use those upgrades.
The hotend withstands very high temperatures, but since the printer does not have an enclosure, it is not easy to print more demanding materials such as Nylon. So far, I had no problems printing PLA, ABS, PETG and TPU.
The Z axis is moved by 2- 8mm trapezoidal rods, which are not bent and do not generate any wobbles.
Since the stepper motors are driven by A4988 drivers (the cheapest ones), they produce some noise during movement, but it is bearable. After a few months of use, linear bearings (also low quality bearings) begin to rattle, so it is advisable to replace them with more expensive ones.
All things considered, however, it is a fairly quiet printer.
Operation and known issues
The Geeetech i3 Pro B is a machine that divides opinions among its users: there are those who think that it is the best 3d printer in relation to price/quality on the market, and there are those who believe that it is not worth spending money and time on a machine that brings more problems than solutions.
My opinion is that this 3d printer is the best you can get for a budget of around $150. In addition, since you are the one who assembles the printer, I believe that the reliability of this machine depends purely and exclusively on your skills. Until now, after more than 2 years of using it, almost all the problems I had were the result of my mistakes when putting it together, that’s just how it is.
For example, I had some issues related to loss of steps in the motors, in the movement axes and with the extruder. This was because the supplied A4988 drivers do not come with the proper voltage/current calibration and that’s because you are the one who should regulate them according to the torque they will need, which is an easy task.
At another time, I had problems when changing filament, since there was a clog in the barrel that prevented the placement of the new filament. To fix this, I found that it was necessary to manually extrude some material before making the filament change.
This way, the plastic is soft and does not block the barrel. I suspect this is a recurring problem with the MK8 extruder, as a metal tool is provided inside the box. At first, I didn’t know what it was for, but at the third blocking of the barrel, I realized that this tool allows you to push the hard filament in and unclog the barrel. I did not find this information in the manual or documentation for the printer, however, which they definitely should’ve included.
Another problem I had was during my first printing, after finishing the assembly of the machine, I did not pay attention to the nozzle size and tried to print as I always did with my other printers. The loss of steps alerted me and when checking, I verified that the nozzle provided in the Geeetech i3 Pro B is 0.3mm, when the diameter in my other printers is 0.4mm. Fortunately, the thread on the heater block is M6, which is also used by most nozzle manufacturers. By replacing it, it started working perfectly.
Compared to most low-cost clones of the famous Prusa i3, the Geeetech i3 Pro B is the best 3d printer you can get for under $200. Its structure is very firm and the metal parts are rigid. This means that no vibrations are transmitted to the printed objects when printing at 40mm/s. When this value is exceeded, you start to see some ghosting in very sharp corners.
No wobble is observed on the Z axis and the geometric precision is at correct values on all axis.
- Its price / quality ratio is the best in its range
- assembling it gives you a lot of experience
- The quality of your printed objects is quite good
- The structure is well designed and very resistant
- As this printer is based on the Prusa i3 model, it is very easy to find spare parts and pieces to modify it on the internet.
- Its low-quality components have a short service life, so they need to be replaced.
- The extruder is difficult to disassemble, and it has no reduction in its gears, so it needs a larger motor to work, adding unnecessary weight to the X axis.
- The glass of the heated bed is too short, and does not cover the entire printing area. You will have to buy one that allows you to take advantage of all the space.
- The assembly process is very complicated and it is normal to make mistakes, causing you to have to disassemble some parts several times until you get to do it correctly.
- The PSU could be of higher power, to speed up heating.
The Geeetech i3 Pro B is a really good printer if you consider the price. Sure, it’s a clone of the Prusa i3 and maybe the components aren’t as high quality, but it also costs about 5 or 6 times less.
Like I mentioned throughout the article, I think that this printer is ideal for anyone who already has experience with electronics and with 3D printer assembly, at least if you want to avoid a lot of headaches.
If you’re a complete newbie, then I’d recommend going with something simpler, like the Ender 3 (link to the review of my own Ender 3 Pro 3D printer) since it comes partially assembled and you should have it running in less than one hour.
I hope this information was useful!