My 3D Printer - Prusa PRI-MK3S

My completed kit-built printer, in the process of printing my first [successful] test print.

This is a stock image of the Prusa PRI-MK3S kit I purchased in December 2019 ($749 plus $49.17 delivery). Because the printers were on back order at that time, I did not actually receive the printer until Jan. 16, 2020.

Unboxing and Assembly

I'm not going to go into a lot of detail here - there is already plenty of build information available online for this printer. But I will post a few pictures to track my progress.

[Jan. 16, 2020]

Package didn't get delivered until late in the evening:

Box was well-wrapped.

Ready to open the box.

Lots of parts inside!

All of the parts are packaged very well. Parts are bagged or boxed and labeled for each stage of assembly.

Spent about 2 hours getting organized and completing the first stage of the build: Assembling the frame and Y-axis. So far, I am impressed by the build quality and design, and the well thought out instructions. I started the build on my surface plate to ensure a good flat surface for assembling the frame, so some of the stuff in the picture has nothing to do with the printer.

[Jan. 17, 2020]

Moved to the work-bench where the printer is going to live (at least for a while).

Completed X-axis.

Completed Z-axis.

E-Axis (Extruder axis)

Adding the hot end and cooling fans

Cable bundle for extruder assembly

LCD panel

Heated bed and power supply

Running all the cables to the controller

Getting close to the finish line here. This picture shows all of the cables and connectors running into the controller. There are a LOT of cables going into a very small space. Getting these connections right is critical - a wrong connection can destroy a component.

This is a good stopping place for today. Tomorrow I will re-check all the connections and hopefully finish the build.

[Jan. 18, 2020]

Zero progress! Heavy snow last night. Got about half of it cleared and my (8 year old) snowblower died. Well, I was planning to get a new one after winter anyway, when they went on sale. No such luck - had to go out and get a replacement. Some assembly required, of course. The had to finish clearing the rest of the snow, so the day was pretty much shot.

[Jan. 19, 2020]

Finished the build. Except that when I ran the self-test it failed.

As the saying goes, "Nothing is idiot-proof because the idiots are so damn smart!" Turns out I did not get the hot-end assembly quite right, so I had to do some dis-assembling and re-assembling, which fortunately only took about 20 minutes. Once I had it back together it took a while to run it through various calibration settings so it was ready to print.

First Test Prints

My very first test print (Prusa logo) seemed to be going well, but then there was a jam at the print head so I had to abort it. Just have to make some calibration adjustments and try again.

It took a few more failures, but I finally got things working properly. The problem was that the print was curling and lifting from the print bed. Cleaning the print bed (dish detergent and water, followed by acetone) and raising the bed temperature to 111% did the trick.

Here's the first successful test print, still on the print bed.

Advice to builders

Manual : The printer comes with a paper manual, and an online manual. I recommend using both. Unfortunately the photos in the manual are not always clear - much better views are available in the online manual.

Kit building golden rule : Don't throw out anything until you have successfully completed the build and verified everything is working. This includes boxes, parts bags, wrapping, etc. The kit comes with a bag of spares, but if you accidentally throw out a part not in the spares bag . . .

Good thing I followed my own advice. I had misplaced the SD card included with the kit, but found it in the "discards."

Tools : The printer comes with all the tools you need to build it, but the build will go much easier if you use some additional tools.

Here's a photo of some of the additional tools I used (from top left going clockwise):

Top left : Cable tie puller/cutter (tightens the cable tie and cuts it off automatically).

Wire cutters : Best way to shorten toothed belts.

1-2-3 block : I just happened to have one of these, but a small block of wood would do just as well. Use this to support odd shaped parts so you don't press them flat and accidentally snap something.

Small wrench : Use to hold nuts for tightening. An M3 nut driver would be even better, but I don't have one.

Small screw drivers : Flat and philips.

Screwdriver with hex bits : Use this for driving screws; much faster than hex wrenches. Get a kit with 20 or so interchangeable bits if you don't already have something like this; good for many things.

Digital caliper : For checking screw lengths.

Flashlight : Helpful for checking in tight spaces, wiring, etc.

Magnetic parts tray : I already had this, but most of the parts are stainless steel (not magnetic) so really any kind of small parts tray is good. I consider something like this absolutely essential! Once you empty out a parts bag, it's easy for things to get lost.

Not shown : A plastic shoe box - I used this for holding large plastic parts. I try not to just set parts out on the workbench because it's just too easy for something to get lost.

More Stuff to Buy

Line many other pieces of workshop equipment, once you have the basic machine you still have to spend money on it for expendables, improvements, and other stuff. Here are some of the things I have already purchased (or am planning to purchase):

  • Filament - different colors, different kinds

  • Large plastic container to store filament

  • Re-usable dessicant (silica gel) to keep filament dry

  • Nylon dish-washing brush for cleaning build plate

  • Octoprint add-on

Newbie lessons learned

Printer axis directions and limits (facing front of the printer):

  • X is 0 (left) to 252 (right)

  • Y is 0 (front) to 212 (back)

  • Z is 0 (bottom) to 210 (top)

PrusaSlicer : Didn't think to set my printer type when I first started using the software (duh!). Apparently PrusaSlicer defaults to "Mini". There are also a few gcode enhancements that can be added to make life easier:

  • In PrusaSlicer go to Printer Settings -- Custom G-code -- End G-code and edit the home X axis line to move the extruder and bed to more convenient locations at the end of a print:

    • G1 X160 Y180 Z125 F3000 ; home X axis