Adventures with our Prusa

We started a new kinda farm on our farm! We got ourselves a 3D Printer, a Prusa i3 MK3S to be exact (what a mouthful!)! Bet you haven’t seen many “farms” with one of those haha! Here’s a highlight of the past month in which it took our derpy-selves to learn how to actually get it to print things. Turns out, it’s not a turn on -> get amazingness kind of machine.

First some back story. What the heck is a 3d printer?

A 3D printer is a machine which uses plastic material (called filament) to literally print out a 3d object by melting this filament and laying out each layer of the object. It works layer by layer from the plate of the printer up to the top of the object, raising up a fraction of a mm each level before laying down the next. And this process is mesmerizing to watch. As a fun fact, the Prusa (the machine itself) is made up of parts printed by other Prusa machines (and if that doesn’t melt your brain a bit, you’re more broken then we are 😉 )

We had decided to get a 3d Printer a few months ago but (like the semi-responsible adults that we are) determined that it shouldn’t be a spontaneous purchase but instead one which we would reward ourselves with for finally closing on and selling the Luther property (my previous house before we moved to Jefferson – you can read about that adventure here (Closing on an Acreage)!

We decided to order the kit vs the fully assemble printer. We both have a fondness for building and doing things ourselves. And the idea of building something we had been waiting for almost six months together hit us both right in the feels.

The kit arrived, with a free spool of filament and we got a crackin. The level of complexity I think was a bit more than we were expecting. Not necessarily hard individual steps, but more so in terms of the sheer number of steps and how critical it was for those steps to be done in the correct order and very precisely in order for the subsequent steps to be successful. The only plus to this level of required focus is that Prusa uses gummy bears to measure progress and motivate you to keep at it

And for me the organization of both the parts and the instructions was glorious. Each core part of the instructions worked towards one specific goal – example “build the extruder” (the thing that poops out the melted plastic) or “assemble the X-axis” (the left/right movement) or “Y-axis” (the front/back movement) or the “Z-axis” (the up/down movement). For each goal, there were two bags each clearly labeled – one bag of parts and one bag of fasteners. And all the bags were layered in separate boxes, ordered by the order they would be needed. On step one? Grab the top bag from each box. Seriously, the organization, was glorious.

The whole assembly took us almost four nights after work, about 9 hours in total. However we did crack one of the pieces partially. As it was mostly still attached and seemed to still be working, we placed the $3.50 PETG (the filament type) part order and continued on ahead!

Once assembled, it was time for the configuration. Luckily the Prusa’s have a number of features which make them pretty glorious over other similar style printers:

• Self leveling bed! Most printers have a knob in each corner you have to tighten a specific amount in order to try and get everything level/flat. This levels everything auto-magically.
• Setup wizard! This checks/confirms all your assembly steps have allowed you to create a printer within the correct specifications.

We ran through the wizard and got everything all tuned up. The belts all moved as expected. The extruder (aka filament pooper) passed it’s left/right, up/down checks, and the bed was leveled. Next up the configuration print test. Here the printer was going to print some long single layer line with rectangular switchbacks followed by a solid filled in single layer square and you have to manually lower the nozzle by ~0.002mm at a time until the filament looks “squished.

Knowing what we know now, we would do this entirely differently, something we’ll go on to talk about in our next blog post. But at the time this was how the manual told us to do so. So do it, we did.

Let’s consult the manual:

I wonder if this is “squish” enough:

Can’t tell, neither could we. So we kept lowering it and lowering it, and then I scrapped it into the bed with the extruder nozzle which is the one thing they super duper tell you not to do. #thisisfine But we got it to a level which looked decent (future-self: you are wrong…).

However we were having another issue, our squares looked like this:

And when we did larger prints, the layers shifting was much more noticeable:

So we went back to the configuration wizard, and discovered there was an issue with the Y belt (front to back belt under the print bed), so disassembled that bit and re-tighten it. Turns out it was slipping. Print instructions would say: “slide bed forward two notches” and the bed would slide forward four, then it would lay down a layer. “Slide back four” and it’d slide back two, and poop down another one, and so on. Getting further and further “off” of the correct value.

Next it failed at the initial bed leveling. More googling later got us to realize the PINDA probe (aka the sensor that detects how close to the bed you are and actually does the automatic bed leveling) wasn’t close enough to the nozzle. It’s supposed to be just slightly above where the tip of the nozzle is so it could detect the bed. We loosed some more things, and moved it down a bit. And it finally leveled!

Then it got to the extrude test. Everything heated up and then nothing. Just a click, click, click sound. We googled a bit, and loosed a few things and tugged out the filament. Retrimmed the end to a point, and reloaded it. Nothing extruded, nothing happened, just click, click, click.

Okay, google said, your nozzle is clogged. We used the provided acupuncture needle, heated up the and rammed that up into the nozzle. Nothing. We tried what are called cold-pulls where you insert, partially heat up and then yank out the filament to see if you can melt the stuck filaments onto the end of the new filament and pull it out. But nope. Each pull came out clean. And it continued to click.

More googling later. We caved and ordered a new fancy titanium nozzle (for later when we sucked less) and a bunch of cheap nozzles for current practice. They arrived a few days later and we youtubed a video on how to remove it. So two wrenches in place, we calmly heated up the nozzle to 215° C (required temp for PLA) and turned it. Right-y Loosey, Left-y Tighty … wait.

Yup, we snapped the nozzle in two. Leaving half inside the printer and half in our pliers.

We tried everything to remove the broken nozzle bit. Even so far as to by a reverse drill bit and try to reverse the threaded nozzle out. But all we did was create a nice fine layer of brass bits everywhere and continued to strip the nozzle :-/

So we ordered a new hotend (the entire bit of the extruder which includes the part that heats up and the nozzle) more than we needed, but it all came pre-assembled, which at this point in our printer-adventure was a blessing. Thank god something that should work.

We got it.

It was wired up backwards.

We complained, they sent us another one. We assembled. The wizard completed. We crossed our fingers really tight and hit print. And it did the base zig-zag square print!

So we can print. As this blog is already a giant novel and if you’ve made it this far:

Our next blog will be on HOW we did things differently this time in configuration in order to get the amazing prints like this one below: