An honorary Duggar

Nophead’s Mendel1 has produced 15 sets of Mendel parts, and is hard at work on it’s 16th!!!  My understanding is that it would take about 60 hours to print a full set of Mendel parts.  I have to admire anyone who prints up Mendel/Mini-Mendel parts because of the amount of dedication it would take to do so.  After spending 90 hours2 printing something, I don’t know that I could part with it.

My point is that we really have guys like Nophead, Spacexula, and Cyrozap3 to thank for cranking out parts and pushing replication forward.

I hereby bestow upon you gentlemen the Duggar medal of continuous replication.

  1. I don’t know if he’s named it yet – so I’ll call it Anna until he corrects me. []
  2. I’m just assuming it would take me 50% longer since I don’t know what I’m doing… []
  3. Dude, I realized yesterday I’ve been misspelling your name.  I’ll go back through and fix that – sorry! []

New affordable 3D printer – the Ultimaker

Ultimaker

Ultimaker

Update 3/28/2011:  The Ultimaker is available for pre-order!

Erik de Bruijn along with a newly formed Dutch RepRap group have put together this new design for a low cost RepRap alternative.  The stated goal of their blog is “designing/developing an easy to build low cost 3D printer with a small form factor but large build envelope.”  Erik has invited everyone to comment on this beta design.  It’s interesting to see their progression of prototypes in their second blog post.

The interesting thing about this model is that it combines some of the best parts of Darwin and MakerBot and what appears to be a Bowden extruder.

The very nature of FDM1 means that the robot will only move the Z axis a little bit every once in a while.  One of the design drawbacks to the Darwin was that the heavy extruder head (motors, gears, heating elements) were so heavy that the entire robot would rock or vibrate with the lateral XY movements.  MakerBot got around the heavy extruder head problem by moving the platform in the XY and moving the extruder head only up and down.  This design decision isn’t without it’s tradeoffs, however.  One downside is that their build area is much smaller than a Darwin.  Another downside of the MakeBot design is that once the object being built reaches a sufficiently large volume or height, moving the object around quickly on the XY platform causes it to vibrate, shake, and become somewhat unstable.

One of the main improvements inherent in the Bowden extruder is that it allows you to take the heaviest parts of the extruder head, separate them from the rest of the extruder head, and move those heavy pieces to a different location.  Using a Bowden extruder makes a Darwin style robot much more feasible – the small moveable print head won’t have the mass to cause the robot to become unstable.

It seems that combining either of the X or Y movements with the Z probably won’t matter all that much, since the Z axis will only move about 0.33mm or so per layer and the Z axis typically doesn’t operate at the same time as either the X or Y axis.  Combining the as the new RepRap version II, Mendel, design shows us that combining the Z axis along with either the X or Y axis, but not both, can lead to a very stable configuration.

What I like about the Ultimaker design is that it would appear to incorporate some of the best parts of the MakerBot and Darwin designs. It appears to have a bolt/nut/T-slot MakerBot style assembly structure using thin lasercut wood pieces for the body.  I found these parts to bolt together very quickly.  Contrast this to the Darwin/Mendel structure using lots of nuts and threaded rod and printed plastic parts to hold it together.  At the same time, by making use of a Bowden extruder and the Darwin body shape, it appears to be able to use most of the interior volume for printing.

I suspect it probably uses fewer parts than a typical Darwin, but I can’t be sure.  I also have to wonder about the cost of lasercut wood versus the cost of nuts and threaded rod.

Nice find RepRap Log Phase!

  1. Fused deposition modeling – basically creating a layer and then fusing a new layer on top of that layer in succession to build up an object. []

Optimal RepRap sizes

To my thinking there’s basically two optimal RepRap sizes (in terms of build area):

  • A small RepRap with a build area just large enough to replicate it’s largest part, one at a time
  • A large RepRap with a build area large enough to print all of it’s own parts in a single print job

Random tangent:  wouldn’t it be cool if all RepRaps came with the designs for their own printed parts already on board?  Just fire it up for the first time, calibrate, and start printing replacement parts.  (I realize this isn’t quite feasible – in order to be ready-printable the files would need to be in S3G format and the machine would have to run the STL’s through it’s own Skeinforge settings).

March 21, 2010 | Comments Closed

What’s so great about a RepRap anyhow?

When I read the RepRap blog or the RepRap builder’s blog I see people printing incredible things in PLA.  And I never hear about their troubles with PLA.  Nothing about it jamming or being fussy about temperatures.  What am I missing?  What are Darwins and Mendels doing that my little MakerBot isn’t?

The RepRap Prize

A commentator suggested that the RepRap Challenge prize is set up to avoid paying out.  This seems like a silly and vacuous charge to me.  The $20,000 and $80,000 prize payouts have firm award dates of 12/31/2012 and 12/31/2015, respectively.  If someone hasn’t achieved the specific milestones by those dates, by the terms of their declarations (and assuming they are good to their word), they’ll have to award those sums to whoever is closest.

In any case, here’s a summary of the list of the requirements for those interested.

Interim Personal Manufacturing prize of $20,000.00 to be awarded on 12/31/2012:

  1. Print at least three different materials, including one that is usefully electrically conductive.
  2. The ability to print electronic circuit boards.
  3. Print beds1 must be of a material which may be reused with minimal refurbishment for at least 20 print cycles.
  4. Maintain a total materials and parts cost under $200 and that 90% of the volume of the printer parts be printed.2
  5. Demonstrate a build volume of the printer above 300x300x100mm in order to insure that items daily utility can be printed.
  6. The capacity to print a full set of parts for a complete replica of itself within 10 days unattended save for clearing no more than one printer head jam.
  7. The ability to print autonomously without a PC attached.
  8. Uses no more than 60 watts of electrical power.

Grand Personal Manufacturing Prize of $80,000.00 to be awarded on 12/31/2015:

  1. That the cost of the material used for printing does not exceed $4/kilogram.
  2. The capacity to print a full set of parts for a complete replica of itself within 7 days, including the time for reloading, and clearing of printer head jams.3
  3. Maintain a total materials and parts cost under $200 and that 90% of the volume of the printer parts be printed.4
  4. Participating teams are expected to regularly publish and make available their technology on an ongoing basis. All technology developed by participating teams becomes open source under a GPL or BSD license. Therefore, the winning team will have to have published at least some of their innovations more than 12 months before the deadline.
  1. Print beds are flat surfaces onto which parts are printed. []
  2. Print beds are not necessarily a permanent part of the printer and are not figured into either the cost or the volume requirements of a printer. []
  3. According to the article it currently takes approximately 21 days with 90% of the time requiring human involvement. []
  4. Plastics such as HDPE and Polypropylene, of which millions of tons exist as waste matter, may be suitable candidates, and recycling of such waste material would be viewed favorably by the judging panel. []

Things I learned while soldering opto-endstops

The opto-endstops marked the very first parts I had to solder for this MakerBot.  Not having soldering anything more complicated than two wires together, this was an adventure and learning experience.  Here’s what I learned today:

  • The 3-pin connectors used for two of the opto-endstops (on the Y-axis stage) are in the Generation 3 MakerBot Electronics Kit (Mostly Assembled) with some of the other connector bits.  I was a little confused about this for a while.
  • It helps to lay out all the little bits in an organized fashion beforehand.
  • Keep a long thin rigid stick handy for bending delicate leads into the circuit board holes.
  • Although I read the RepRap electronics fabrication guide and found it helpful, I still felt a little lost.  I found the most effective way to solder the parts in was to:
    • Get the soldering iron good and hot
    • Put the leads through the holes
    • Bend the leads a little so that they stayed in place
    • Flipped the board over so the leads were sticking up
    • Touched the solder to where I wanted the joint
    • Gently stroked the solder with the soldering iron tip towards the joint
    • This process seemed to create a pretty good joint
  • You’re going to burn a finger at some point, accept it.1
  • This almost goes without saying, but go slowly.
  • Check and double check the orientation and placements.
  • I found it helpful to take a large sheet of aluminum foil and shape it into a tray.  This helped contain the parts I was working on and was a good way to catch the flying leads that I clipped off.
  1. I burned two. []
December 21, 2009 | Comments Closed

MakerBot Ordered!

MakerBot CupCake CNC

MakerBot CupCake CNC

Ever since hearing about the RepRap project more than a year and a half ago I’ve been dying to make/build/buy one.  This last May I got to see an actual MakerBot CupCake CNC print a lego right in front of my eyes at the 2009 MakerFaire in San Mateo.  One of the best parts was getting to meet Zach Hoeken Smith, Bre Pettis, and Adam Mayer.

Well, this morning I finally pulled the trigger.

I just ordered a CupCake CNC Deluxe kit from MakerBot Industries.

Here’s the thing: I have no experience working with electronics beyond putting batteries in the T.V. remote.  It’s going to be an adventure!

I can’t wait!!!