3D Printer Buying Guide

Hobbyist 3D printer buying guide, updated February of 2020

I will be talking about FFM/FDM printers suitable for home use, how to choose which one to buy. This is more about my opinion, you should still do your own research, and feel free to come back to me with questions.

Key Attributes

Design

I would say there are 5 main styles:

• Cantilever Arm, such as the Prusa Mini, or Monoprice Select Mini
  • Cheap, least trust inspiring due to rigidity concerns. Can work great if built right
• Prusa-like, or bed-slinger (bed moves along Y), such as the Prusa i3, Ender 3, etc
  • Slinging the bed is makes printing slower and more risky as the print might sway during print
  • Prusa definitely popularized this design way more than I am comfortable with
  • Not the most rigid in this list, unless it's a genuine Prusa brand (because Prusa uses all metal and machined parts, nothing cheap)
• Ultimaker-like (bed moves along Z, head moves along X and Y)
  • My favorite, fast, reliable, easy to understand
• CoreXY, (bed moves along Z, a special arrangement of belts moves the head)
  • Personally dislike, in theory works great, but takes another layer of understanding
• Delta
  • Complex and tall, personally I would avoid.

Print Size

Something like 150mm x 150mm or less is considered small. A "normal" printer can print about 200mm or 220mm wide, it's easy to buy beds and bed heaters around this size. Anything wider is considered large.

For example, a common MK2 heated bed is 214mm x 214mm. The Ultimaker 2 glass bed is 257mm x 229mm. The Hephaestus I designed uses a 220mm x 220mm bed.

Filament Size

There are two choices: 1.75mm or 2.85mm (aka 3mm)

Use 1.75mm unless you have a reason to use 2.85mm. 2.85mm is better if you need speed (meaning extra large printer and extra large nozzle) and have the equipment to handle it. 2.85mm is better for flexible materials such as polyurethane, since the extra stiffness of thicker filament makes it easy to feed. 2.85mm is also required for Ultimaker printers.

Extruder Style

There are two choices: Direct, or Bowden

A direct extruder is one where the motor, the one that feeds the filament into the nozzle, is mounted right above the nozzle.

A bowden extruder is when the motor is mounted somewhere on the printer that doesn't move, the motor feeds the filament into a long tube (called a bowden tube), and the tube leads into the nozzle.

Direct extruders are generally more reliable, less oozing and retraction problems, and better at feeding soft/flexible filaments. They are heavier so they have more momentum, and that momentum causes your belts to stretch slightly during changes in direction. To counteract this, you can either slow down your print, or improve your belt tension and motion mechanisms.

Bowden extruders are cheap, easier to replace, and lightweight. They are less responsive because the bowden tube gives the filament more room to stretch or compress, hence they have worse oozing, worse retraction, and bad for soft/flexible filaments. But the lightweight and compact head design means printers can run fast without worrying about belt stretch.

Nozzle

You will end up starting off with a 0.4mm nozzle, no matter what printer you buy.

But it's a good idea to get a printer that's compatible with the E3D brand of nozzles.

If you plan on printing specialty materials, you should consider E3D nozzles.

Printing anything similar to nylon or have a higher melting point than nylon, you will require something known as all-metal extruder.

Printing abrasive materials, such as carbon-fiber-filled-plastic, or glow-in-the-dark (yes, this stuff is abrasive), you will need a hardened steel nozzle. The standard brass nozzles will get wider and wider due to the constant abrasion.

Don't worry about this too much, I print carbon-fiber-filled-nylon but only for extreme projects like combat robots that need to take weapon hits.

Slicer

Slicer is what we call the software that converts 3D model files into the gcode files that the 3D printer can understand. Do not buy any printer that does not use either Cura or Slic3r as their main slicer.

Common Choices

Ender 3

Currently the cheapest on the market at $240.

It's a kit so you have to put it together yourself.

It's difficult to tune. There's no automated bed leveling. You can add your own upgrade for auto-bed-leveling but it's harder due to it using an outdated 8 bit control circuit.

The mechanics uses V slots and wheels, not the usual linear rods. You need to make sure the wheels are aligned and tightened. The Z axis is also only driven from one side so the tension on those wheels are extra critical.

It looks like a Prusa style motion mechanism but I think it's a hybrid between the cantilever arm style and the bed-slinger style, because the Z axis is supported on both sides but driven only on one side.

Since it's so cheap, the community is rather large. Tuning tips, repair instructions, and upgrades, are all available from the community.

Bowden extruder, nozzles are Micro-Swiss.

CR-10

Pretty much a bigger version of the Ender 3, much bigger actually. Some people who own a "good" printer still get a second CR-10 just because they need something massive.

There's a few variants that have a second Z axis drive.

Bowden extruder, nozzles are Micro-Swiss.

Ender 5

They look nice, a bare but sturdier frame than the Ender 3, with a X-Y motion system (still with wheels, not linear rods or linear rails), bed on Z axis, but with the same extruder and electronics as a Ender 3.

I'm not recommending these because they are kind of niche, not a lot of people have them so you won't get much help using them.

Prusa Mini

As of today, still only in pre-order phase. But the reputation that Prusa has makes this a very attractive option at $350. It's a decent build volume and cutting edge 32 bit electronics.

Bowden extruder, compatible with E3D nozzles.

Prusa i3

Currently the version is MK3S. Depending on if you are getting a kit or the assembled unit, you are looking at $750 to $1000.

Cutting edge technology, most tuning and calibration are automated.

Highly recommended, almost every part is well documented and replacements are 3D printable. Huge community for support as well. Can be upgraded to print multiple materials.

Direct extruder, compatible with E3D nozzles.

Ultimaker 2+

I own one of these for 5 years now, but mine is heavily repaired, upgraded, even with my own firmware edits.

$2500, works out of the box, and will continue to work for a year or so before it shows problems. It's weakness is that the bowden extruder has many parts that might need to be replaced (don't worry, very cheap parts) once every few months. If you do enough upgrades, like I did, this is no longer an issue.

Ultimaker publishes the design of every single one of their parts, so I can design my own upgrade parts very easily. Spare parts are plentiful to purchase. The firmware is open source, so I can add my own edits to it. Ultimaker also writes the Cura slicer, so Cura works best with Ultimaker printers (and still works with other brands too).

Bowden extruder, compatible with E3D nozzles (only the 2.85mm ones). Only uses 2.85mm filament!

Ultimaker 3

I have one at work.

$3500, absolute workhorse. Again, works out-of-the-box. No problems with the extruder system at all. Can print in two materials at once.

But... if you get a blob-of-death, it could, in one go, destroy the bed level sensor, fan wires, and heater all at once. This is extremely rare. If you can't fix this yourself, then it is also EXTREMELY expensive. A new print core (aka the part with the heater and temperature sensor) is $120. A new print head assembly is $400. Soooo you better know how to fix it if it ever breaks.

It can work on a WiFi network and is reliable enough that you can remotely start a print without worrying about it. It has a built-in camera too that you can watch over WiFi.

Anet, Geetech, etc

Do not buy any of the "Prusa knockoffs" please. They are sometimes fire hazards. They use cheap laser cut acrylic where real Prusas use aluminum.

Makerbot, Flashforge, Dremel, etc

Very unreliable, expensive and poverpriced. Uses proprietary software that makes it difficult to use the machine beyond it's expected life.

SLA printers

Prusa and other companies are coming out with SLA printers, which uses a laser and liquid resin to make very highly detailed prints.

The prints are indeed very nice. But the plastic is weaker. You absolutely need to be able to handle messy chemicals and have a dedicated space to work with those chemicals. Really... Dawn dish soap can't wash this crap off my hands, gloves are a requirement. The prints need an alcohol bath when they are done, and should ideally be cured under UV light (you can get an UV oven, or just use the sun). Plus, think about disposal as well.