Have had a number of conversations about 3D Printers and what I would recommend lately so I thought that I would capture some of the thoughts from those chats.
First, if you are really in a hurry, and you have a lot of free cash, and want to get out there and buy something right away, I would recommend the Ultimaker 2+. I have the Ultimaker 2 with part of the upgrade, the interchangeable nozzle system, that comes with the + and it is a great printer. It is also an expensive printer. It is also better tuned, IMHO, to printing materials other than ABS unless you either have a cover for it, or have it in a warm and climate controlled room.
So, if you want a less expensive printer than the Ultimaker 2+ then I would recommend one of the Makerbot Clones of which there are at least three and probably many more! The one that I had was the Wanhao Duplicator 4S and it did a masterful job of printing ABS once I added a ducted fan to it (see here in this blog for details).
Finally, if you want to spend the least amount of money possible, while still getting a capable printer, then go for a Prusa kit. Select one with a steel frame as that will serve you well for precision in the future and then learn a LOT while you construct the bloody thing. Not for the faint hearted but easily doable by someone with a modicum of assembly skills.
There is also a Prusa I3 that you can get assembled from Wanhao for $399. I do not have experience with this particular printer but Wanhao did a nice job on the Makerbot Clone that I mentioned above and this printer looks similar in terms of quality.
Lastly, which is even more finally than finally, there are some low cost entry level products like the M3D that would probably offer the easiest way to start printing. They are only a little cheaper than the Prusa I3 from Wanhao but should be easier to run. The downside is that the printer will have a smaller build volume, be slower, and less versatile assuming you stick with printing!
The above are my recommendations based on what I know...or in fact...based on what I did. Here are what I would look for if I were researching printers from scratch:
Open is really good - First on my list of open would be to discount any printer that insists on its own filament supply! You want to be able to buy filament on the open market and not be restricted to what is available in your specific cartridge. You may still end up preferring an expensive supplier over a cheap commodity but at least you have that choice. Second on my list of open would be the firmware that drives the printer. The open choices are going to have the largest community to draw on and that can be important when and if you have a problem.
Rigid frames are really good - The more rigid the frame that supports and encloses your printer the better as this is important for accuracy and long term dependability. If you build a Prusa get one with a steel frame!
Heated build plates are good - Not essential but definitely handy even for PLA as it does help with platform adhesion and subsequent release!
Being able to print ABS can be good - I think that PLA is a great material to print with for a number of reasons. It is a lot easier, faster, and in my experience better for detailed work, that ABS. It is also bio-degradable and does not smell when printing. It does not require the high heat of ABS. My problems with PLA are that it will degrade and it is sensitive to heat so some things are not right for it! My other issue with it revolves around prints that need support. I find PLA support to be much harder to remove than ABS support.
Enclosed can be good - If you plan on printing with ABS then you will need an enclosed printer unless your work area has a very controlled environment. Mine certainly did not and since the Ultimaker is partially open I had to buy second party add-on covers. More about this here. The bottom line of this point combines with the point above...do you really need to be able to print ABS? If not then I do not think that you need an enclosed printer. This opens up a lot of options.
Two extruders are not needed - I don't know this for a fact but I would be willing to bet that 98% of the printers sold with two extruders never use the capability of having those two extruders. It is bloody difficult to get one extruder working perfectly and to get two of them singing together is that much harder. In addition to the cost, it also adds weight to the extruder assembly and I just don't see the need for it...and I really tried with my Wanhao. Now there are some really good two extruder printers out there and I would 'def buy one...but I would not have two extruders as a requirement.
Active cooling is very good - The first Wanhao Duplicator 4S printers shipped with a mother board that did not support active cooling. This has been rectified now but I had to wire my own manual power supply and switch to be able to install the cooling solution that I mention above. Active cooling is not needed for all kinds of printing but can be essential for some.
Wireless is not essential - Wireless is a nice to have not something that should be high on the list to steer you from a printer that other wise meets your requirements. If you really want wireless you can get an SD card that enables that capability. Even with wireless you still need to visit the printer as few of them have arms. BTW, if you are going to do short prints across USB fine, but for long prints, do them from the SD card!
Manual leveling of a build plate is not hard - once you get used to it anyway! This is one of those requirements that I would put as more nice to have than essential. Automatic leveling may become the standard but it is not now and making this a requirement will exclude a lot of good printers.
Strong user community is really good - It is amazing how much support you can get from the user community. The stronger the community around a printer the better. If not around the printer, then around the type of printer. For example a Prusa user can go to the Rep Rap forum and find a lot of other Prusa users. A Makerbot clone user can go to a Makerbot forum and find help. Etc.
Noise is the nature of the game - You put four servos to work and you are going to make some noise. The Ultimakers have a reputation of being quiet...but they are still noisy. I don't really see this as a requirement. Your spouse is still going to complain.
Easily interchangeable nozzles are epic - Game changing, even life altering! But I am not sure that you can really make this a requirement as not many printers make this easy. Possible maybe but not easy. Hence I put it last. On the other hand if you do have the capability you will wonder how you ever got by with out it! Read more here.
I think the above sums up the most important points that come to mind.
For the best reviews of 3D Printers that you will find anywhere check out those on 3D Hubs. These are reviews by people that are serious enough about printers to be selling their printing services.
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