Kingroon KP3S PRO S1 Review

The KP3S Pro S1 is a new 3D printer from Kingroon line of printers. Today, we’ll provide an overview of the 3D printer, touch on its features, capabilities,  and price. We’ll also conclude with our thoughts on the overall performance of the unit.

Let’s get started.

Kingroon KP3S PRO S1 Review 1


(NB: Use Coupon Code GB20off for $20 OFF)

Kingroon KP3S PRO S1 Review

For starters, the KP3S Pro S1 is an upgraded version of the KP3S Pro printer, which is a small great printer for the beginners. We highly recommend the cheap printer for 3D printing for beginners. The two printers look similar in build but one easy way to differentiate them is, the KP3S Pro uses rubber rails while the KP3S Pro S1 uses linear rails.

Features of the KP3S Pro S1

Technical Specs

Product Model KP3S Pro S1
Technology FDM
Print Volume 200*200*200mm
Machine Size 320*325*360mm
Packaging Size 510*450*190mm
Net Weight 6kg
Language Firmware CN/EN Klipper
Print Via Web/USB Flash Disk
Machine Power 200W
Input Voltage 110V-220V
Power Supply 24V 12.5A 300W
Feeder System Full-Metal Hotend
Printing Accuracy 0.05-0.3mm
Nozzle Max Temperature ≤260 C
Heated Bed Max Temperature   ≤100 C
Max Movement Speed  ≤500mm/S
Max Printing Speed ≤500mm/S
Recommended Printing Speed 200mm-350mm/S
File Format STL/Obj/Gcode
Machine Leveling Support
Material Break Detection Optional
Power Off And Continue Printing Temporarily Not Supported
System Requirement Win7-10/Mac/Linux
Slicing Software Cura/Slice/Host…
Nozzle diameter 0.4mm
Print Bed Heat Bed With PEI Sheet

Here is a summary of the main specifications of the Kingroon KP3S Pro S1

  • It uses the linear rails on all three axes
  • it has direct drive extruder with 3:1 ratio. This means it is great for TPU filaments
  • The build form is 200x200x 200 mm in all three axis
  • It is quiet
  • It has built-in power supply unit. With the previous KP#S,s the power supply unit was separated. Having a built in power supply unit is better for safety reasons. Also, it uses a smaller footprint on the desk.
  • Installation time of just 15 minutes, almost like the like Bambu, but only for the hardware. Additional time will be needed as there is some manual settings and leveling to be done.

We also got this 1kg pink PLA filament for testing.

What’s in the Box?

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Items in the Box

The KP3S Pro S1 comes well packaged with form to ensure everything is nicely protected during shipping. Inside the box, we have:

  • The user manual
  • Screws and nuts (2 Z-axis lead screws, 3 M5 screws, 2 T-nuts
  • 1 nozzle
  • Printer base
  • Rigid clamp coupler
  • Pre-assembled Z and X-axis with a direct extruder
  • Power cable and data cable
  • Tools (1 diagonal pliers, set of allen keys, open-end wrench
  • 1 card reader and memory card
  • Balls for use during installation
  • 2 racks (Spool holder)
  • Consumables (Sample filaments, spare parts, etc)

The spool holder designs look out of place. It’s not clear how to use the filament with the spool holder.

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Now that we know what’s in the box, let’s get to the installation process.


To begin, we start with installation of the Z axis. To do so, screw the first T-nuts on the platform in the area where the Z axis will be installed. Next, lower the Z axis platform on top of the screwed T-nuts and use two longer screws on the back to secure it in place.  Finally, the screw in the two smaller M5 screws from the bottom.

The next step is to install the lead screw into the coupler. All these steps are outlines in the user manual.

The printer bed is covered with  a PEI sheet, which is what we recommend.

From here, you have finished the harder part of the installation. You don’t have to set the V slot wheels because the printer has linear rails.

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It’s always a good idea to quickly check the tension on the timing belts. You can adjust the tension by twisting a knob for the Y-axis and another one for the X-axis. Check the switch to confirm that the voltage is set correctly for your country. For US, you have to set the voltage to 115V while for Europe and countries from other continents, set the voltage to 230V. You can get this information in the installation manual.

Next, plug in the power cable. The cable is about one meter in length.

At the back side of the printer, you’ll find the limit switch for the Y-axis. There is also a silver knob for setting the position of the Z-axis. We’ll come back to the switch at the leveling stage.

The Kingroon KP3S Pro SI also has filament run out sensor. Install the spool holder on the side where the filament runout sensor is. If you want to place the spool holder somewhere on the top of the printer, you will have to come up with some custom solution because the natural filament path for the direct drive extruder is from the top.

There is also a reverse Bowden style tube. When the direct drive extruder pulls the filament, it goes inside the where the filament sensor is.

It will be challenging to use the sample filaments with the KP3 Pro SI’s spool holder. Therefore, we recommend having your own filament for the test.

Leveling the Bed

The next step is to turn on the 3D printer and do the leveling process. The KP3S Pro SI has assisted bed leveling. When you press a button, the printer’s nozzle moves automatically on one corner of the bed. You can then rotate the wheel on the bed to set the correct distance between nozzle and the bed surface. You have to repeat the process for all the four corners and then in the center.

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Leveling the Bed

To finish the leveling process, insert a paper between the nozzle and the printbed, lower the nozzle until it presses on the paper just enough to enable it to move around when pulled.

With that done, it’s time to put some filament on the spool and do some printing.


To begin, preheat the nozzle to the required temperature of the material you are using. After reaching the optimal temperature, insert the filament and let’s print something from the manufacturer that is in the SD card.

The files are in Chinese. So, you have to find a way to translate them. You can use Google Lens or any other similar app. We renamed the files appropriately, i.e., robot, dice tower, XYZ calibration Cube and the famous benchy.

The printing starts nicely, with the first layer nicely coming out. You can adjust the print settings on the visual interface on the printer. First, you will need to pause or stop the printing. Use the intuitive buttons to change the temperature of the pedal or nozzle, change the filament, set the fan and the printing speed, and so on.

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Printing a Test File

Our first test print took 26 minutes to finish. We tried removing the model from the bed and it was held nicely. This just proves that the KP3S Pro SI has excellent bed adhesion. You’ll have to wait until the bed cools down to easily remove the printed part.

The test print looks nice and the first layer is even okay. Some seam lines are visible on the back side but that’s typical with silk filaments.

Next, we printed the benchy. The first layer wasn’t perfect but it finished. If you have a glass bed, the first layer is likely to be wobbly. That’s why we recommend buying the KP3S Pro 3D printer with a PEI  bed.  The PEI bed is  more forgiving when it comes to human errors.

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The Printed Benchy

The benchy looked good. There were no problems on the side surfaces. The first layer wasn’t perfect but it was acceptable. The seam lines were quite hidden but the back text was not readable. Generally, the quality was quite good from the printer.

The dice tower finished printing in 21 minutes. The quality of the print was acceptable but not that perfect.

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Printing the Dice Tower

When reviewing a machine, we also like to test the printing in spiral or raised mode. For this printer, we don’t have to use the Z Hub and the traction. We printed the low polybase from Printer Plus and this is how it came out:

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We then decided to print something from flexible filaments. We chose the TPU95 by Polymaker. Inserting the flexible filament was a little bit tricky but we managed. The first layer printed perfectly. The bed surface was only 40 degrees. There was some little stringing between two objects but these were easy to remove after the print.


The KP3S Pro SI is easy to use because it mostly comes pre-assembled. The assisted layer feature makes it easy to level the print bed. The quality of the build is guide and the build volume of 200 x 200 x 200mm is decent for someone who wants to get started with 3D Printing.

But even the best thing is the price. With just about $200, you can own this 3D printer and other KP3 series. These printers have their place on the market because of their price and in print farms that print smaller items that can fit their build volume.

The KP3S PRO S1 has some improvements over the previous version. For example, the SI has linear rails on all three axes,  filament runout sensor, stronger yellow springs for holding the bed in position, bed tensioners and also and inbuilt power supply.  For the previous KP3S, the power supply unit was separate from the machine and this made the whole unit to take a larger workarea.

However, for the bed, we recommend getting the KP3S PRO SI that has a PEI sheet rather than one with a carbon glass sheet. The glass sheet is very sensitive to human errors. If you get it, ensure the distance between the nozzle and the surface are precise. A little bit too close or too far and your print will have some issues. We recommend getting the flexible PEI sheet.

Also, the spool could have been better. We’ll mount our spool on the top. From the looks of things, we’ll somehow have to move the filament run out sensor to be between the spool holder and the nozzle.

When you’re installing the lead screw, pay attention that it is clean and then put some grease on it. Also, pay attention to the position of the hotend cables and the teflon tube.

We can highly recommend the KP3S Pro SI if you want to enter the world of 3D printing. The printer’s build area is enough for beginner projects. And the price is quite cheap. This would make a perfect 3D printer for beginners.


(NB: Use Coupon Code GB20off for $20 OFF)

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