What? More Of The Same?
Nope! After a year and a half with the printer(s) I find myself being asked for advice about buying a printer and what to do when that advice is taken. So, rather than repeating myself in email, I figured I'd post a quick update. If you don't have a 3D printer, I'll understand if you sto... hey - you already stopped? Well, ok.
Microcaliper ($20) - I'm not sure how I missed this the first time. I use this thing a LOT. Not just for prints, but once you can measure something to within 3/100th of a mm, the tool makes its own jobs: how thick is this credit card? Why does this paper feel so light? Is resume paper really thicker? The cheaper models only measure down to 0.2mm, but you want to get finer than that. You can spend more, but it won't really be useful here.
Nozzle/Cleaning Needle kit ($8) - Brass nozzles wear down and, more frequently, get clogged, so you'll want to have some spares on-hand. But before you toss a nozzle you think is clogged, try cleaning it. The needles in this kit are precision-made to make sure they don't enlarge the nozzle's opening. They're also a great way to test your new nozzles to make sure the opening is as big as it should be, which is just what I did after ordering a cheap pack of 20 0.4mm nozzles. In that bag, only 9 were ready to go immediately, 7 needed some assistance from a 0.4mm needle to enlarge the opening and 4 had holes too small to be opened at all. The kit I linked above also includes a variety of nozzle sizes. Why would you want a bigger one? They print faster at the expense of appearance. You can also go smaller to get really fine layers. Just make sure you get nozzles compatible with your printer. This pack will work with many Makerbot, Creality and Prusa, but I make no guarantees.
Splurge Nozzles (variable) - I've been printing for over 18 months and the only reason I've had to discard nozzles is clogging - I've never worn one out, but it is possible if you print a lot. You can spend a bit more to get stainless steel ($7 each ) instead of brass, which not only last longer, but will let you print with more abrasive filament like carbon fiber, fiberglass, etc. Make sure to read the reviews carefully - cheaper ones are usually junk. You could also go all-in and get a ruby nozzle for $100, but if you do, make sure you get a real one. The $60 nozzles appear to be junk too.
What To Print First
Sure, go ahead and print your Benchy. It's a rite of passage. After that, though, you're going to want to learn more about your printer and dial it in to get better, more reliable prints. There's a slew of parameters which can make a huge difference, so the only way to find those is testing: starting temperature, 1st layer temperature, bed temp, 1st layer bed temp, print speed, retraction distance, retraction speed, etc. Here are some of the tests I've found most useful:
Print SpeedTest_speeds-6mm.gcode then pick the speed that looks best for the rest. All other things being equal, faster retraction is generally better because it saves time. Using the speed you chose above, do the 2-10mm distance test to narrow down the distance range. Now that you have the range, choose a finer distance test, e.g.: 2-5mm, or 3-8mm. Unless your printer is direct-drive, you probably won't be in the 0-2mm range. With your chosen distance, redo the speed test at *that* distance. Use that retraction speed and distance in your slicer.