Some of the stuff in here is what I wished someone had told me when I started.
Eat opinions like a great chicken dinner, eat the meat, and leave the bones! Limited to my experience with extrusion FFF FDM printers only.
A bit about me:
I have printed literally tens of thousands of pieces, all on single extruder printers with just manually changing filaments at specific layer heights. There are some small, some multiday prints, some requiring days of post-printing gluing and sanding (you can check out my Carcassonne, Scythe, Terraforming Mars and other stuff offered on Thingiverse, and that’s just the stuff I have shared). These printers below have been running 24/7 since I got them. So with the design models I have done, the processing, and the amount of printing and tinkering, while I don’t consider myself a professional, I’m certainly not a novice at this either.
Currently I own two 3D printers. I started with an original Prusa Mk2 about 3 years ago that I upgraded to a Mk2S then a Mk2.5S. Now the very good MK3S is out. With the exception of a firmware issue with the Mk2.5S it has been very reliable and is a real workhorse. Keep in mind when I purchased it the price was about $800usd. The upgrade to the mk2S was another $90, and the upgrade to the MK2.5S with replacement rods and bearings were another $300. So over the course of these three years I have invested A LOT of money in this machine, $1200 plus dollars, AND I am still having an issue with the new VV2 PINDA probe. Prusa is a great company that makes quality stuff, but in my opinion you slightly over pay for this experience; but, at the same time, the experience for this kind of money is unparalleled.
My second printer is an Ender 3 Pro I bought about 18 months ago. Out of the box it has been an OK experience, when it prints it is close to the quality of the Prusa but has not been as reliable as I would like. Using a .20 nozzle for very fine detail has been near impossible to dial in for consistent prints. You will have lots of failed prints if you are a stickler like I am on quality to get the settings just right, and then have to change it on the next print using a different manufacturer of PLA. So if you don’t mind a ton of trouble shooting, this printer could work. My ongoing issue with my Ender 3 is inconsistent "elephants foot". I know all about first layer adjustments, it's just inconsistent. (It seems there is a ratio between Linear Advance and nozzle pressure that I have not sorted out yet, it's complicated firmware) so sometimes a bit of trimming at the base of the print is needed. My Initial cost was about $240usd and since then I have done a complete refresh with dual z rods, all new bearings, an e3 silent board, and gone through a couple glass plate beds. I also have gone through a couple mods of the direct drive extruder. Currently it's with a 4 wheel direct drive carriage (to support the DD better) that I custom made a Hydra compatible dual fan mount for. I do tons of filament changes in my prints so this was necessary for me. All together I am at about $460 total for a year and a half with this printer.
A Bit about Firmware
Keep in mind any custom changes to a printer often require a firmware modification. If you are not computer literate at all, don't be changing your printer. If you are, there is great online help to make the mods, but it does take some trial and error.
A Bit about Slicers
For me there have been two great FREE slicers out there - PrusaSlicer and Cura. It used to be I found I could tweak each slicer no matter the printer and model to work well, now with the latest versions it seems like I am using the PrusaSlicer for the Prusa and Cura for my Ender. Both work well but need dialing in to work best. The PrusaSlicer is invaluable for simple layer change of filament colors built in (available in Cura as well but not as user friendly) and for the ease of support enforcements and blocks that allow you to only put the minimum of supports you require, both great tools.
A Bit about filaments,
PLA is the most widely used filament. This is my go to filament. The only bad thing I have experienced is when you print a part that gradually widens as it goes up, you can get some “pla curl” on the overhangs as it prints. The issue is when the nozzle moves it can catch on the curl and layer shift or knock the print off the bed. The solution is to slow the print way down, lower the hotend temp as much as you can (and still have it print), and lastly make sure you are blowing good air onto the part as it prints. There is a difference between some premium and economy filaments. “Most” of the premium or plus filaments will simply provide a better print in the end, sharper corners, less stringing, and when very dialed in they can be perfect. For bulkier items where real fine detail is not needed, I have found the “cheaper” filaments do just fine. For where I live, if I want a very nice print I turn to Esun PLA +. There was a Silk PLA I used that must have had some TPU in it because it pulled the glass right off the print bed I had. It had a bit too much stick, so not all PLA filaments are alike. I have even found between batches from the same company that there may be color or property variations or updates, so if you have a big project that requires multiple rolls of the same filament, buy it all from the same place all at once. You can import a model into PrusaSlicer, set your printer and settings, and preview the amount of filament needed and time to print, which is very helpful for your purchases. My Prusa with a .25 nozzle and a .05 ultra-fine layer height with PLA Plus (a very long print time) have made some of the smoothest, best prints for showing off what this technology is capable of.
PETG is used for printer parts where you may need a higher heat tolerance. It is less brittle than PLA meaning you can drop it more and it not chip or shatter; but it is more difficult to consistently print with. Use a glue stick to PREVENT the filament from sticking TOO much to the bed. Esun has worked well for me when I needed a PETG print. For me the PETG I have used always had a slight sheen to it and never looked as pleasing to the eye as my PLA prints, so if I have not really needed to use it, I don’t.
TPU is available with different measures of stretch and bend. If it is a big piece you are printing, forget about printing it with anything else but a direct drive extruder, no Bowden tube here. Use a glue stick as well on your bed or you could pull off the surface. Supports are also harder to work with as they basically need to be cut off the model instead of snapped off.
ABS, if you are new to printing and do not have an enclosed printer then save any printing with ABS until you are very familiar with printing, otherwise it will drive you nuts with your print curling up off the bed.
If you want to print the occasional thing or a single project and are on a tight budget, wait a couple months and get the New Ender 3 V2 with some updates (it has the new silent board). Make sure you get the carbon glass plate and use some “Magigoo”, and have at it. And remember this is an “entry” level machine that is VERY good FOR an entry level machine, but that’s it. You can always get something better down the road if you decide to stick with all the pains and joys that come with 3D PRINTING.
If you see hundreds of things out there that you want to print and have the budget for it, in my opinion the Prusa MK3S is worth the two - two and a half times investment over the new Ender 3 V2 with a glass plate. You get to print all the different filament types you will want to experiment with, the removable sheet bed is great. Out of the box there are no real upgrades needed, and you will have a reliable machine with some yearly maintenance that will last and just keep turning out quality prints. There is a reason it wins all these awards. If you can afford it, I highly recommend it. One more thing… the printing community is anticipating the release of a “large format” Prusa so watch for this.
Now the question of Size… this is exactly where I am at right now. I want to print larger items like a full-size adult cosplay helmet…in one piece. If you like projects that involve lots of gluing and sanding and painting, then either the Ender 3 V2 or the Prusa MK3S will do you great. It will be lots of work but VERY rewarding. I am, however, one of those people that have been there, done that, and am ready to get my piece off the printer in one “almost” finished piece. Fortunately for us, even within the last year, we have seen many larger format economical printers pop up. You want to be able to print a minimum 350x350x350 size cube, and preferably if you are bigtime into Cosplay and want bigger pieces like chest plates, you will want to go 450 plus size.
Wider format needs aside, I actually think the idea of having a more expensive workhorse AND a less expensive tinkerer is not a bad idea at all. Quite often, between tweaking or upgrading something on one printer, the other continues to print so I never really have down time and one is always available for an “emergency” print. This scenario has actually worked quite well.
About 3D printing
There are lots of helpful videos to help you get started. It is not an overly complicated or difficult thing now. Five years ago, maybe, but not now. BUT, EXPECT to have to spend considerable time to get started to where it is actually “fun.” Failed prints and tweaking are just part of this experience, so get used to it. If you are doing something like a full armor set, EXPECT to take a full month JUST printing, that’s how things are, VERY rewarding but you've got to be prepared to put the time into it.
Last bit of advice: Get the first layer RIGHT, this tells you everything about the print, it needs to be consistent, attached well to the bed, and solid at the right thickness . If this is not right then don’t expect the rest of the print to go well, stop the print, make your adjustments and restart! There is nothing worse than a 20-hour print not turning out how you want it to be! Adjust, tweak, retry, retry again, get it right and hopefully after 20 hours you are smiling with the results you wanted.
Last bit of Advice for tools: Youtube IT! It is not IF but WHEN you encounter a problem or issue, because you most definitely will! Chances are someone else has too and already posted some help there… search, search, and search some more …good help is out there.
About STL download sites:
Places like Do3d are a very welcomed thing in the 3D printing world. There is no shortage of things Online these days you can download and print, some free, some reasonable, some outrageous, some bad, some good. Seems what Do3D is attempting to do is to make some great models that are very detailed, accurate, and fantastic to the eye, BUT, are also actually 3D printable. Up to now there are many models that are 3D and look great... on the computer screen, BUT, they were not designed from the ground up for consideration on how they may be actually printed with a current technology 3D printer. That’s where I hope Do3D actually excels and it looks like they are.