Tag: RepRap

Full RepRap for sale

A complete1 Mendel for sale?  That’s incredible!

There has been a truly amazing progression2 in RepRap parts lately.  While I’m not crazy about eBay as a way of selling3 , it’s a very democratic4 way of disseminating RepRap parts.  The first few parts and sets of parts were all printed, then molded, now MOLDS are for sale?!

Yes, the Platonic ideal of RepRap is that a machine makes the components of the next machine.  But, is it not also part of the RepRap ideal that these machines be disseminated as far and as widely as possible?  It’s really great you can use a RepRap to build another – but that doesn’t mean it’s the best/most economical way.

These RepRap mold are advertised to be good for roughly 50 pourings.  It is advertised to create 9 vertexes at once, but they all appear to be 1/2 vertexes.  The posting also suggests it takes 12 vertexes for a full RepRap.  So:

  • 12 vertexes per RepRap / 0.5 vertexes halves = 24 vertex halves required
  • 24 vertex halves required /9 vertex halves per sheet = 2.67 sheet uses per RepRap
  • 50 uses per sheet / 2.67 uses per sheet = 18.75 sets of RepRap vertexes

Admittedly, this is only a set of molds for the frame vertexes, not the entire set of parts.  However, it’s really only a matter of time before a set is up for grabs.

This makes me wonder – is there a different market value to printed parts rather than molded parts?

  1. ish [↩]
  2. transmission?? [↩]
  3. having sold things on eBay myself [↩]
  4. fair? capitalistic? [↩]

Significantly less disgusting than friendship bread

So-called “friendship bread” is a ball of dough you cultivate, add ingredients, split off some of the dough, give away some of the dough, make bread, and keep a little bit around to cultivate for the next batch.  Whoever gets some of the dough then does the same.  I guess the idea is there is some sort of continuity between all these loaves of bread everywhere though (oh dear god forgive me for saying this) time and space.1

Whenever I think about friendship bread I throw up a little bit in my mouth.

What I find far more interesting…  is the idea that someone could have a RepRap where every plastic part came from a different machine.

  1. I don’t profess to be an expert on friendship bread.  I could have some of the finer points wrong. [↩]

If wishes were fishes…

…we’d all cast nets.

There certainly seems to be enough people wishing for RepRap/RepStrap parts.  RepRap forums, MakerBot Facebook  page, and various other forums/pages have a lot of posts from people asking for RepRap parts or expressing a desire for the fundage for parts or kits or promising some sort of exchange of goods (at least one offer of “services”) for parts/kits.

I wonder how many people out there want a set of Mendel parts.  I also wonder how many people out there want sets of electronics.  Now I wonder just how many RepStraps there would be in the world today if everyone who wanted one had one…

Seems like only yesterday

While searching up a link to the eD’s first sketch for the Mendel I realized that post is about a year and a half old.  That made me wonder how long I’ve been interested in the RepRap projected.  I first read about it in a SlashDot article back in April 2008.  I remember thinking that a DIY level 3d printer was just a fantasy.

Now, I’ve got one sitting in the next room and objected printed with it all throughout my home.  (Several window latches, a sugar packet holder, various little toys, etc).

What’s even funnier is realizing that I’ve been boring my friends and family with RepRap talk for more than a year and a half as I enthusiastically gushed about the possibilities of printing ANYTHING on a homemade printer than can make copies of itself.

Enney Meaney

It occurred to me today that a lot of people are using their RepStraps to build Mendel parts.  Then I wondered, “How many Mendels are in operation now, anyhow?”

I would guess a dozen or so – with far more on the way.  What I find interesting is the seemingly large proliferation of Mendels (or, at the very least, blogs about Mendel parts and construction) versus the dissemination of Darwins within the prior year.

If this is the case (and I really have no evidence of this, just my impressions), is it something about the RepRap project that has suddenly taken hold?  Something about the Mendel over the Darwin?  Is it the increased RepRap documentation, more YouTube/Vimeo videos?  Is it the availability of parts on eBay, plastic/resin parts from molds, or something else?  Is it MakerBot?  Thingiverse?  Facebook, Twitter, MakerFaires, or MakerTweetBook?  More mainstream coverage in the media?  Was is health care reform, killer bees, or the loss of the Mars rover?  Is it subliminal messages embedded in the MakerBot website?  Have we been plugged into the Matrix?!?!

I know someone is going to say “a combination of these things” – but really, if you had to pick one thing, what would you say it is? 1

  1. P.S. I’m voting for the killer bees. [↩]

Fair wages for Robots!

Several hours ago I posted about two eBay auctions for full sets of Mendel printed parts.  I just checked on them to check out where the two auctions ended.  One ended at $446 (actually, at 330 Euros, for a seller located in Ireland) and the other at $455 (seller located in Ohio).

Why, then, would an auction just two days ago go for $630 (rather, 420 pounds)?  A sale at 420 pounds implies someone else was willing to bid 415 pounds.  I’m guessing it’s a combination of factors that went into a $600+ sale – perhaps because the English really want RepRaps, people wanted to support Adrian Bowyer, anyone who bought RepRap parts from Adrian himself can basically be assured they’re getting quality parts.

This tells me $450 seems to be the going rate for a set of Mendel parts (for now).  This raises an interesting conundrum.  Will the prices go up as more people become interested in RepRap?  Will the prices go down as people start printing and making available more RepRap parts?

Either way, suppose the going rate is $450 for 60 ‘bot hours.  That’s $7.50 an hour.  This is less than the minimum wage in California!1  This means if human help is required at all in the production of RepRap parts, the entire process is taking longer than 60 hours and the hourly rate is even lower than $7.50/hour!

I’m not saying RepRap parts should cost more.  I’m just saying I was really getting used to the idea of a gnome sitting in my living room earning above minimum wage while I slept.

Oh well, I guess I’ll just have to take solace in running a robot sweat shop.

  1. $8/hour right now [↩]

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).

Mendel FAIL

I can’t find my camera, so my camera phone will have to do. Here was my second attempt at printing Spacexula‘s Mendel production STL files.  Don’t even ask about the first attempt.

RepRap Mendel FAIL
RepRap Mendel FAIL

Spacexula offered some advice on how to fix this.  I have the Stretch feature turned on so that I can (hopefully) print better small circular features without the parts getting all globby.  He suggested turning Stretch off and just drilling out the holes if needs be.  Wise words from a man cranking out Mendel sets.

Unfortunately, I won’t have time to spent printing up parts until the weekend.  :/

These parts are not unusable.  Of the 13 parts on the sheet, I think five are probably perfectly serviceable.  The tall toothed gears are the most miserable parts – they are swayed and the teeth are basically intermittent bumps.  This has been one of my least successful completed prints in a long time.

Anyone want some Mendel parts?  Drop me a line.

My own plastic gnome

…or Minimum Wage Rights for Robots!

MakerBot posted a screenshot of a RepRap Printed Mendel Parts auction that sold for 420 pounds – roughly $630.84. 1  2  Others have been posting RepRap Mendel auctions as well.  One just sold for roughly $453, another for about $270, with two more auctions around $450 each with at least 3 more hours to go.

Using Spacexula’s Mendel production files, 24 STL sheets of parts, averaging 2-3 hours a print, we’re talking roughly 60 MakerBot print hours. 3  Assuming I only have the patience to print up one STL sheet a weekday and two sheets on the weekends, starting on a sunny Sunday like today, I could finish in 19 days.

Assuming very little human intervention, $600 for 60 hours of MakerBot operation is a pretty good deal.  It’s like having a fussy gnome who eats electricity and plastic living in your home and earning just above minimum wage for you. 4

  1. According to Google and at the time of this post. [↩]
  2. I couldn’t find a link to the actual auction at first, but then figured it must be a private auction.  It turns out this was the RepRap eBay auction posted by Adrian Bowyer a little while ago.  You might need to be logged into eBay to visit that link. [↩]
  3. This assumes no failed prints. [↩]
  4. You know, like those shoe gnomes that made shoes for the cobbler in that children’s fairy tale. [↩]
Test