Thoughts about 3D Printing, Prusa and Prusa's i3 MK3


I'm new to 3D printing as of 2018 - by choice.

I've been home shop machining for 20 years. For most of that time I've been 3D modeling and CNCing. Mind you, that was from the good old days when nobody even sold "kits" for the home market. Mostly you bought single axis drivers and breakout boards and cobbled it together. It was a time when one mis-wire could cost you countless hours chasing down bugs or blow your whole electronics set up. It was a big deal when folks started selling multi axis boards with limit switch I/O, opto-isolation and integrated printer ports. I've been through the stepper vs servo arguments. I've studied the differences between uni-polar and bipolar steppers, single step and multistep, supply voltages, etc. I've been through direct drive, vs geared drive vs belt drive. I've weighted the cost/benefit between all thread, "precision" threaded screw, plain ball screws vs hardened and ground ball screws. I won't call myself and "expert" but I've been around the block a time or two.

Many years back my son introduced me to the RepRap project, telling me that it was going to "reproduce itself" and only require a $100 investment to get one up and running. And I rained on his parade, telling him it just wasn't gonna happen... Certainly not that easy and not that cheap. I hadn't even been aware of issues like cooling fans, heated beds, enclosures and the like. But I know a pipe dream when I see one.

Out of the gate the project was pretty screwed. The mantras seemed to be "self replicating" and "cheap." To achieve the first goal, printable plastic was used for as must of the design as possible - regardless of whether it made structural sense or not, it only had to make political sense. To achieve the second goal, people were people were using big box hardware, surplus steppers, scrounged parts (often from old printers) when possible and pathetic drivers.

Sure it "worked." But according to the "official version of the story" it took from May 2, 2004 to February 9, 2008 - 4 years! - to "successfully makes at least one instance of over half its total rapid-prototyped parts" out of Polycaprolactone (PCL), basically glorified slue sticks. And they boast "Not counting nuts and bolts the latest RepRap can make 70% of its parts ..." (clearly marketing hype - 70% by parts count, volume, weight, cost? - most of the machine is struts, steppers, wires and electronics) and "... future versions of RepRap will be able to make their own electric circuitry." Good luck with that...


All these many years later 3D printers, manufacturers, projects, groups, YouTube channels and and users have proliferated. And there seems to have been a necessary divergence. Some folks, mostly the "everything for free" folks, have doubled down on the "cheap and self replicating" mantras while others, Prusa included, have ditched both in favor of practical, producible and profitable.

One of the down sides to crowd-sourced intellectual property (doubly so when you come late to the party) is that it's hard to know who invented what, who just ran with an idea and who's self promotion is taking credit for what.

a diverge and one wrong 15 of those years and 3D modeling Place holder to be written later.


Content and imges copyright © 2006, 2012 by Jeff Jones