Let’s clarify a confusion about FDM 3D printing: "Quality" between different machines is not equal; it’s extremely subjective.
Every FDM machine, whether Stratasys, Intamsys, Creality, Essentium, or others, can achieve the same level of accuracy and print "quality." The difference is how FAST and how repeatable the quality is.
Basically, each machine squeezes molten plastic through a small nozzle, (motor/hardware accuracy is negligible). Some companies claim 50 micron accuracy, or 11 micron accuracy, or 12.5 micron on the Z and 25 micron on the X/Y, etc. These are all, basically, misleading. The REAL factor is to put the tool head WHERE you want it. Then other factors come into play, like nozzle size, material rheology, and thermal expansion.
Yes, some hardware is capable of achieving 11 micron steps, with a motor/driver/pulley combination. However, when you squeeze plastic through a 0.4 mm orifice (give/take a few mm), the hardware’s capability is negligible.
The most important factors are repeatability, a 3D printer's robust mechanical build, and a crucial open-material-machine skilled operator to determine proper settings! These determine print quality. Do not be fooled by company "accuracy" statements.
Some new $200 printers print PLA perfectly, accurately, and very well. Other $75,000 printers produce the exact same result. So, What’s the difference? WHAT do you get in a $75k+ machine?
Three factors to consider are: 1. Repeatability, 2. Hardware, and 3. Software.
1. Repeatability
Generally, as a 3D producer, you want to build multiples of the same part, and you want them exactly the same.
The difference between a $70,000 and a $700 machine is how it's physically built, plus the quality of electronics, bearings, frame, and materials. Cheaper hobby-level machines are made from 3D printed parts. But when a machine moves rapidly, the joints will often loosen over time. As a result, you lose accuracy and overall quality very quickly!
2. Hardware
On industrial machines, like the Funmat HT or AON-M2, frames are built of STEEL, and everything inside is CNC'd aluminum/other metals. This means the machine stays calibrated much longer; it won't "shake itself loose." So, your parts will be more consistent, over a longer period of time, without tearing down the machine or rebuilding anything.
For example, if you put a printer made of plastic into an oven, it will go out-of-spec even faster. That’s why, builders who put their CR-10s into a heated chamber (which helps ABS, Nylon, and Polycarbonate printing), have machine hardware that simply cannot handle the heat.
And if you accidentally bump a CR-10s5 (large format, cheap printer), you need to re-level the bed, adjust the frame, and get it back to spec. If you bump the Funmat PRO, it’s not affected. However, the Funmat PRO costs about 20x as much.
3. Software
Most open-material machines today have a selection of software to choose, as a toolpath generator, telling the printhead where to go. Referred to as Slicers, there are two main players on the market today: Simplify3D, and Cura. There's also Slic3r, Mattercontrol, and a variety of other open-source slicers. These are different from design software, like Solidworks or Fusion360.
For 3D print accuracy, the key is process development! You'll likely burn through 10 parts, to tune a new geometry in a new material, exactly like other machining tools. On a CNC, you're going to make a pile of chips, until you know your fixtures and standoffs are right. And it's the same with 3D printers: Test, Test, Test, then it will produce well.
The primary difference between Stratasys machines and others is partly machine and material prices. More important it’s software! Stratasys machines do everything for you; other machines require an operator. Still, you’ll be spending 10x on materials, service, support, and when your machine breaks down, they’ll come out to fix it -- for a price.
Remember, the operator makes a part look good and be accurate; a machine repeats operator instructions over and over, consistently.
Cheers!
Rob
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