These are the notes I made while I was assembling and setting up the 2020 Prusa i3 kit from Folger Tech. It may be of interest to anyone thinking of purchasing the printer, or anyone curious about the nuances of setting up an i3 kit. Presented in chronological order:
There’s some metal on the set screws – not too surprising for cheap hardware.
Using set screws makes there be a small angle where the main frame pieces connect, as the force isn’t acting from the centre of any component, and there’s a slight bit of play in all the components. This didn’t seem to be an issue in the end.
My heated bed is black, which I much prefer to the red one in the pictures online. Nice!
The holes in one of the 3D printed bearing mounts were too small for the bolt, making it really hard to tighten. I stripped the heads on two bolts and had to use pliers on the nut and bolt to tighten. Turns out I had an allen wrench that was one size too small, and there was a correct size one in the bags with the flexible metal couplers. Nice!
The side of the bearing mount should capture the lock nut so they can be installed easier. I’m big into nut capture. If you’re designing something to be 3D printed and you’re not under size/thickness constraints, there’s no reason not to capture nuts (and even counter sink heads).
Stripped another bolt. Bummer.
Aluminum heated bed platform was really bent and was definitely made by hand. Probably got bent in the mail, and it wasn’t too hard to straighten out.
Everything is taped together with kapton! Everything!
Pro tip: get an egg carton for the bolts. It took 20 minutes to sort them at the beginning, but it was totally worth it.
Would be nice to have some washers on things. I’m a huge washer fan, and there aren’t as many as there should be on this kit.
— end of day 1 – (2 hours)
Power supply is a little bent up.
Power supply pot is really sketchily soldered.
A few pins and the voltage regulators on the ramps board are bent up. The PTC devices are also bent a bit (not surprising).
The machining on the rod holders and other parts is really nice! Fillets all over the place and they’re solid aluminum.
Looks like a genuine Arduino! And the steppers are Folger Tech branded. Pretty slick.
Missing a 2 pin molex for the extruder. Could be a major hang up for some people. You could instead use female header pins or a chopped up IC socket like I did.
Bed thermistor molex is way too big. It’s pretty wiggly.
Cable management is going to be a struggle on this bot!
Stripped more bolt heads. This time it’s on the x motor mount. The stepper wiggles a bit. I think I’ll mod the mounts so they wrap around the motor, as well as having holes for the bolts.
End of day 2 – 4 hours.
All that’s left to do it cable manage and wire up the power connections to everything.
Used a picture frame as my build plate glass. PLA wasn’t sticking to the glass, so some cheapo painter’s tape was applied. Cutting glass is hard – submerging it in water while cutting kept it from shattering, but I wasn’t able to cut a straight line. Still a cool trick though.
Build plate is somewhere around 180mm^2 due to the bad cut on the glass.
Repetier host is a pain. Can’t figure out how to home the machine. Seems like everyone’s printers use a different home corner.
First injury! Burned myself on the extruder. It’s called the ‘hot end’ for a reason.
Wiring instructions are really clear, but my extruder ran backwards. Took forever to figure out where the problem was. The fix? Flip the plug around!
Repetier host is strange. Let’s switch to Cura and see if it works.
Things are acting weird. Every time I plug in the board, my computer turns off. I’ve seen this issue before – it’s because of drawing too much power over USB. Why is it drawing more power? Haven’t changed anything.
No clue. Unplugged things – could’ve been the RAMPS board (the extruder motor specifically – I fiddled with the pot when I was diagnosing the reverse extruder problem). Still not playing nice with my laptop. Ok on the desktop though.
Uh oh! There’s some blue smoke!
The 5V regulator on the arduino is obviously toast now. It cooked itself. Still not sure why, but at least it’s an easy fix.
Had to bodge in a TO-220 5V regulator. Luckily I had some 7805s that went up to an amp, the same max current as the 1114 on the mega. Different pinout though, so it’s currently hanging off some wires. Had to chop the SMD one off the pads and hijack them with my wires.
It works! Always have spare ‘bread and butter’ parts – saved me in this situation! Still no clue why the regulator decided to die – maybe it’s not a legit arduino board?
Cura is sweet – very simple setup and likes the bottom left corner as home. Extruder is now working, time to print!
Wait, better make sure everything’s squared up and tight first. Took a little fiddling with the end stops too.
Printed my first object – a block with my initials on it. They turned out backwards! Now it’s a stamp!
Bed adhesion isn’t a problem. Pretty tricky to get the prints off. Maybe heating will make it easier?
I’ve got a ton of hardware left over. Overall, it went together quite easily. It was a shame to be missing the molex connector, and it’ll remain a mystery as to why the regulator blew on me. But the hardware seems to work well (the mechanicals), although it would’ve been nice to see more washers, and a little smarter design on some of the 3D printed parts, the machine is very sturdy and is working quite well on the test prints I’ve done so far.