3D Printer Comparison: $200,000 vs. $2500

A few years ago in grad school I spent about a month designing a 3D printed case for a Raspberry Pi + Camera [0]. We used a Makergear M2 (a $2000 printer at the time).

The process had some frustrating moments, but overall it was an amazing experience. 3D printers allow for a wonderful iterative design process. Come in in the morning, pull parts off of the printer, measure, test fit, etc. Tweak in CAD, or start working on the next part, and start printing your changes/additions before lunch. By mid afternoon the print is done, and you usually have time to do another round of changes that you can start printing before you leave for the day.

Of course, this is all assuming that your printer is working continuously and that you're ok tossing a lot of filament from those test prints. My experience with the M2 was that typically I could get it dialed in and it would print great for 2-3 weeks before it started misbehaving. Sometimes it was a simple adjustment (re-level the bed, etc.), but most of the time there was no obvious indication of the problem, and I'd spend several frustrating days leveling, calibrating, cleaning, and generally tinkering until it started working consistently once again.

There are also plenty of issues with the print quality and precision, but I've already written more than I intended, so I'll skip them. Needless to say, it was sufficient for our needs. IIRC, our final cost per case was $4 in material (PLA) with a print time of about 6 hours.

It's a fascinating technology, and it's mind blowing how far it's come in the last decade. I'm not sure that the FFF/FDM style printers will ever get to the point where they're ready for use by the general public, but the overall technology is here to stay. I wouldn't be surprised to see 3D printers become as common as microwaves in my lifetime.

[0]: http://i.imgur.com/JkF1WQ4.jpg

Surely the high gloss finish on the black material is drawing attention to a lot of the flaws as well? I'd really like to see a same colour comparison between the two.

the difference in 3d printers and servers is rather hard to compare: different servers can compute the same result, faster, slower, but it'll be the same. not exactly true with 3d printers, where a result isn't binary.

Welcome to the wonderful world of quality control :)

Making something is easy, making something with a high repeat accuracy and very low fail percentage is super hard.

I learned this the hard way myself with an IO expander for the Atari ST that I designed. I needed it to drive the lathe/mill controller, the ST simply had too little IO capacity so with a bunch of decoders and latches I was able to drive a much larger number of motors and relays.

The first one worked like a charm. So did the second and the third. But the fourth, we couldn't get it to work no matter what. Part variability led to some signal arriving just that much earlier causing the latches to remember data that was still stale. The reason was - in retrospect - quite simple, the design had assumed that the input to the latches had long stabilized before the latch pulse was sent. But because on the ST the latch pulse took a different route as well there could occur a tricky situation where the output of the buffer driving the data bus on the far side would still be rising. To make things worse, this would not happen repeatably, only with certain patterns of 1's and 0's. In the end, a single buffer in line with the latch pulse caused enough delay to stabilize the input to the latches and that solved the problem.

(Of course not with every board...).

Anyway, that was electronics, this is mechanics but the same principles apply.

Something funny is happening in youtube land, classical music.

There are a whole pile of 'youtube wonders' that can play an enormous variety of material but that have never in their lives done a live concert. It took a long time before one of those miracle people owed up to the recipe: record hundreds, or even thousands of times. Pick the best.

That's the difference between an actual pianist and youtube miracle workers: a pianist can do what they do repeatably, youtube miracle workers would end up being booed out of actual performances.

Repeat accuracy is very hard, mechanics, electronics, playing the piano, the subject hardly matters.

I've been reading all kinds of books and articles about quality control last year and I believe that in a mature market it is the only absolutely critical element in any production process. If all your competitors are doing good QC and you don't you're dead. Everything else can be fixed but without repeat accuracy you'll be fighting a lost battle.

Another way to look at this is that for real world stuff where there is a whole company dependent on the output of the 3D printer the cheap one is too expensive, and the expensive one probably is cheap.

That's because if you were allowed to make a million parts with each and you could take the best part from each set of parts they'd be very close. The 'best' part of those two might even be from the crappy machine. But if you needed just 50000 parts that would simply work your cheap printer (or even a small army of them) would wear out long before completing the order, and that's what makes them expensive.

Using different material and different infill is a bit of an unfair comparison. Using 100% infill causes more problems with warping due to shrinkage, thus increasing the difficulty. Using 25% avoids this, but decreases stability a bit.

Regarding the print quality in general, I think an Ultimaker 2+ would give you better results (also at a price of 2500$).