Saturday, March 17, 2012

RepRap, the Herd of Hyper Intelligent Cats Chugging 5 Hour Energy

Brian Benchoff wrote a very interesting article over at HackaDay pointing out a problem he sees with RepRap. His position is that RepRap is not standardized enough, and that we Admins should select the winners.

I had to laugh when he advocated "Intelligent Design", which is based off a 2000 year old book of poetry as a model for us to follow. Reality doesn't bend toward fairy tales.

Traditions more than rules

There is currently one main Cartesian bot for RepRap at the moment, the Mendel. You might say that there are 3 : Prusa, Sells, and Mendelmax, but if you look closer they are is effectively only 1.

Prusa, Sells, and Mendelmax Share the same Smooth Rod size 8mm or 5/16, same spacing between the Z threaded rod and Z smooth rod (30mm), Horizontal Z rods, those Horizontal Z rods spaced 50mm apart, and extruder who's mounting holes are 50mm apart, Nema 17 motors, 2 smooth rods on the Y axis, spaced 100mm apart, an equilateral wedge shaped frame, long structural members holding parts printed on another reprap.

Who decided on this? Did the Admins come down from on high and dictate it, or did we hold a council to decide it? Nope, the gravity of the existing design (Sells, and now Prusa), pulls everyone back to these standards because those who share want other people to use their parts, and people who download parts are more likely to change out 1 part more than they are 3-4. Are these the optimal sizes? Likely not, just like having your nerve for your vocal cord go from your brain though you chest and back up to your vocal cords is not optimal, it's just the way things have evolved, and they work. Retiring / Kingmaking Designs's Admins are selected by Adrian from the community at his discretion. Mostly it's people who have done a good bit for the community and our main purpose is to give him advice about the community. We are not paid; mostly we are not commercial interests (well besides selling RP parts or the odd end here or there). We are not the experts, the experts are the thousands, and I do mean THOUSANDS of developers out there. They decide what RepRap's take off, not us. That's how it should be.

We have our personal preferences, I prefer the Prusa Model, some of the Admins prefer Rapman/Darwin style machines (crazy folk), others think Sells Mendel is the best design. I am sure we will get some Admins eventually that think Printrbot/Wallace, because of their lower cost is best, or Tantillus because it's mostly 3d Printable, or maybe even some day a person will win the Gada Prize and someone will think it should be the "official" RepRap. It's a fools errand.

It upsets me that Botmill is still selling a Sells Mendel, and if I had my way I would put a huge sign out front of their website saying they are doing you a disservice by selling you an old design. I would scream to all the blogs that the $50-$75 Printrbot saves you is not worth the loss of print quality at high z axis levels at high speed. But the great thing is Adrian likes the Admins to walk softly.

RepRap: Just another in a long line of Open Sourceish hardware projects.

I am new to Kites, Paper airplanes, CNC, electronic prototyping, kit cars, kit airplanes, DIY PC, Sculpting, etc etc etc etc... What kit should I buy to get started? Go into a forum based around these are any number of others and get ready for a nerd fight. It's no different in RepRap. What's the best beginner 3d Printer? It really depends, what do you want? What do you know? How much time to do have? What do you like the look of? All of these effect your choice in all those hobbies listed above, and they affect us to.

The way I answer the question of what your 1st printer should be is by looking at your technical skill and money level.

If you’re a technically minded person:

$400 and Less Wallace or Printrbot Self Sourced
$500 and Less Prusa with a wades Extruder self sourced
$700 and Less Mendelmax self sourced with a Makergear styled extruder (IMHO the best self sourced machine you can build)
$825 Makergear Prusa Kit
$1300 Mendelmax Kit
$1575 Ultimaker
$1700 Up! 3d Printer
$10,000 Vflash by 3DS

Not technically minded (They want to get to printing ASAP with as little technical learning as possible).

$1200 Assembled Prusa from Lulzbot
$1300 Assembled Mosaic from Makergear
$1700 Up! 3d Printer
$1750 Assembled Replicator from Makerbot
$10,000 Vflash by 3DS

As long as that list is of stuff I recommend, there are tons of options I didn't list, but they should not be thrown away. I would not suggest a Botmill Project to my worst enemy because of their known history of white washing the forums and sending "assembled machines" that are not really assembled. But the last thing I want is for Botmill to go away, maybe one day they will improve their quality and go to a RepRap design less than 3 years old... I will keep waiting. And don't even get me started on the popsicle stick / buggy electronics Techzone 3d printers with wooden hot ends...

You think we are fragmented now? Just give us another 6 months!

Lemon Curry a UV Photopolymer DLP 3D Printer based around RepRap is coming online with several projects running in parallel.

Thanks to the work of Unfold & ttsalo we might actually have a paste extruder that will really work well in the Moineau stepper extruder. So I expect to see commercial Paste 3d printers in the next 6-12 months.

Several People are working on 3d Printed CNC mills ATM, expect to see those soon enough also.

ARM electronics, off-carriage extruders, inkjet multicolor printing, multiple extruders, glass-based high temp extruders.

And god knows what else you crazy developers out there will come up with, next thing you know I will go into the RepRap IRC and will see someone running one of these in their garage.

From one of the Admins to the rest of the RepRap community, keep fracturing, & keep making it complicated for the new folks.  The reason it's hard to decide is RepRap is a candy shop, and Willy Wonka is only just getting started.

Thanks Adrian for starting such a scary fast evolving confusing and beautiful machine as RepRap.


  1. I think to a large portion people will take care of themselves.
    Those who are capable enough to source and build a Mendel should be able to work out for themselves what they want.
    Those who know they aren't ready for that challenge will gravitate toward the the Up and Replicator style devices.
    There is however one place where I think some guidance is in order.
    Looking round I see a lot of people who were lacking practical robotics experience, tried to build a Mendel, failed and gave up on 3d printing. And those failures reflect badly on the community, people who could have made a valuable contribution have instead become negative advertising.
    This is where I see the value of something like the Printrbot kits. I think the complexity strikes a good balance. It's a simpler build than a Mendel, but it's still fully user assembled and that is important because if you didn't assemble it you are going to be less confident modifying it.
    It's a repstrap for the mind. And after the mind is in the right place it can be upcycled into a Mendel.

  2. Agree but I have built both Printrbot, Mendelmax and Prusa. Printrbot is not that much easier than a Mendelmax and honeslty the ORD I think will be a much better 1st printer than most RepRap or RepStraps out there... can't wait to test that one out.

  3. I think that a "Getting Started" video the wiki's homepage would be really helpful to beginners.

    I think that a RepRap competition would be healthy for the group. Have objective categories like "Fastest Print Speed" and "Fewest Components". Having bench marks would give beginners a clearer place to start.

  4. Great response Neil! One of the things discussed years ago with regard to the Arduino was the idea of the fork. There seem to be two camps: those that want dictates from high above of the one true standard or those that feel that the forked development is the way to innovation. If you look at Arduino and their ruling iron fist it has both worked for them in spades but also IMHO stifled creativity.

    The problem with the printrbot is not so much the lower barrier to entry its what happens to those beginners that get real frustrated when things don't work very well at all because of the extra corners cut to make a printer that cheap. Of course things haven't gone well for my students with the makergear prusa either.

    I've built and used, on my own and leading up to 15 college students as a group, 2 cupcakes, a makergear prusa, an eMaker huxley, and most recently a makergear mosaic. The Mosaic is a surprisingly fantastic printer although sure there are weird things about it. In 8 hours after opening the box I was pulling prints off it unlike anything I had seen before with those other machines and in a very short amount of time. Maybe the issue is not how a beginner gets started with Reprap because maybe there are better machines for that.

  5. One thing that has stopped me from progressing further isn't necessarily the main chassis type, but more the combination of electronics, steppers, and extruders.

    I would like to see a big cross reference list, have one for the electronics, that lists:
    Cost (approx)
    Number of motors supported
    Chassis compatibility (Will I work on Mendel only, or generic?)
    Interface options (USB, Serial, SD Card, Wireless)
    Technical Ability required (Learner, intermediate, advanced tinkerer)
    Resolution of parts

    Then do the same for extruder options.

    Give people an easy way to compare the different units that are available. Give them an easy path to make some of the initial choices, or at least give them a way to easily create a shortlist to better suit their needs.

    I know that I spent a long time looking at electronics, and at the end, I was pretty much stumped. I figure all of them are going to work somewhat for what I wanted, but it was hard to compare them all.

    I think that some kind of standardisation is a great idea, and some of the core idea of Brian Benchoff's article/rant is based on a good principle, however your response to it also does point out that there is ALREADY some standardisation inherent in the system.

    However, I don't think that there is a need for more rigid design guidelines, there is a strong need for more linking of designs, and a consolidation or linking between all of the documentation. The issue isn't necessarily that of too many designs, but that for entry into the Brotherhood of the Rep-Rap, choice can sometimes be a scary, scary thing for a newcomer!