Justin Dunham

's journal about making things

Building a Desktop Fabricator (3D Printer), Day 1

Filed under: Everything Else — Tags: , — Justin Dunham on December 31, 2010

The Makerbot box.

Workstation.

The parts for the Y Stage Assembly - structural pieces, bolts, a belt, etc.

Completed Y Stage Assembly, with the Build Platform in the upper left.

 


Today (12/31/10), I began building a Makerbot, which is a special type of machine called a desktop fabricator. A desktop fabricator allows you to print. But you can print objects instead of documents. Remember the replicator, from Star Trek? This the first step toward that technology. I’ll document the build process on this blog.

What do I mean? Let’s say you are looking for a bottle opener – as has happened to me many times. You have a bunch of beers, but you can’t find anything to open them with. If you own a desktop fabricator, you can print a bottle opener. Not a picture of a bottle opener, but a physical bottle opener that lets you open bottles. Or lets say a knob breaks on your over. Print a new one. Or if you want a copy of some tchotchke that someone’s designed. Download the schematic and print one yourself. The technology’s primitive right now, but it’s improving rapidly. And pretty soon 3d scanners will come into their own, and you’ll be able to copy things for real.

So wait, wait. How is this machine able to print things? Well, check out the Makerbot video page for some demonstrations. But the basic premise is that it extrudes ABS plastic, much like honey coming out of a squeeze bottle. This ABS plastic is extruded into layers that make up the object you’re interested in. The layers are pretty thin, so you can create a wide variety of objects.

There are a few limitations, obviously – plastic is the only material you can use right now (with the exception of frosting). The Makerbot is slow; it takes an hour or two to print a complex object, though this is improving rapidly. Lastly, the geometry you can produce is somewhat constrained. For example, you can’t do severe overhangs because the plastic will collapse before it has time to solidify.

But still, I strongly believe that this technology will change people’s lives in ways that we haven’t imagined yet, and this will happen soon, like in the next 5 – 15 years. My favorite way of talking about this is that the desktop fabricator will do to physical objects what the MP3 did to CDs.

Because I believe very strongly in the promise of this technology, I’m hoping to build a business on it at some point. Ideally, I would want to find a way to finance rapid improvements in the Makerbot, for example, a major new version every 6 – 9 months. The machine is an incredible achievement, but there’s lots of work to be done on improving the technology so that it can produce a broader range of usable objects.

Also, I think there could be a lot of work to do on making it easy to build (eventually buy) and use. Right now, you have to use 3 separate pieces of software to create a new printable object. One day, I would like this to be as easy as desktop publishing. I read an article recently that said that at one time, the idea that a home user could produce professional-looking documents on their personal computer was laughable. Today, kids use Microsoft Word, Powerpoint, etc. to create documents that simply wouldn’t have been possible 30 years ago. 20 (10? 5?) years from now, it should be possible for someone to publish an object just as easily.

Anyway, in order to better understand how a desktop fabricator works, how easy it is to use, and what can be done with it, I decided to build one. I ordered the Cupcake CNC kit from Makerbot – there are others, but this one seemed like the best buy and easiest to deal with. Over the next week, I hope to complete the kit and print at least 1 or 2 test objects. I will also document the build process on this blog.

Today, Day 1, I built the first stage, which is called the Y Stage Assembly. I wish I could explain why it’s called that. Y almost certainly refers to the Y (up-down) axis, and the Stage, which is the orange thing in the pictures, is what objects are printed on.

The MakerBot components in the kit are really well organized, and the documentation is extremely good – it even incorporates mistakes that past users have made, and videos are available to make the build process as straightforward as possible. With that said, I am going to use these entries to point out things that could be improved. There are a few things that were more difficult than they could have been today.

  • Some of the parts are slightly different than the pictures in the wiki (for example, a couple of parts now have a Makerbot logo, and the flanges are white now, instead of black). This made it surprisingly difficult to find pieces, since otherwise I don’t know what a “flanged slide bearing” is. It seems like a really small detail, but it actually matters a lot for more naive users, like me.
  • The build quality is not that precise. On several occasions, I had to sand a part down to get it to fit, or holes were slightly misaligned, so I had to work really hard to get a screw into place (while worrying about cracking the materials I was screwing together). Could one of the included tools be a metal rod with a rough surface that makes it easier to sand holes to an appropriate size, or to a large enough size to accommodate imperfections?
  • Early on, you have to get a bunch of magnets into holes, and they all have to be aligned in a certain way. This is because two of the parts are held together by strong magnets, rather than by glue. I think this idea is ingenious, and I assume it comes in handy later although I don’t know when. However, this is an immense pain to gain right, since you’ll put a magnet in a hole, and then fill another hole with a magnet, and the magnets will sometimes jump out and stick to each other. I don’t know what the solution to this is. Scotch tape?

The Four Seasons’ pastry kitchen

Filed under: Cooking Journal — Tags: , , , , , , — Justin Dunham on December 27, 2010

(Very) approximate layout of the kitchen.

Basic ingredients.

Piping out the mixture.

Chef Hales with the final product.

Awesome chocolate decorations!

I had the chance recently to visit the pastry kitchen at the Four Seasons Philadelphia. It’s one fairly large room (I’d say 25′x25′), connected to a very small temperature-controlled room where some completed desserts and various chocolate-related ingredients were kept.

I’ve had the chance to visit a few industrial food production areas, including getting really familiar with some yogurt factories in my days as an investment banker, various public factory tours (such as the Tillamook cheese factory), and now this kitchen, which was definitely industrial-grade.

It always strikes me how a very mechanical, utilitarian place can be devoted to something decidedly non-industrial, i.e. high-quality, complex, delicious food. I guess you can tie it to my larger interest in commercialization and mass production, of which food production is a particularly interesting example because the end product gives very little evidence of how it was prepared. One particular thing I noticed during our tour was a bunch of miniature fruit tarts – the colors of the strawberries and blueberries were conspicuous against the otherwise neutral (metal, cinderblock and orange tile) surfaces.

Anyway, it was pretty neat to see the various tools that are used and how they’re arranged. In some ways it would be a dream kitchen – vast stainless steel work surfaces, and lots of trays, pans, molds etc. hanging up on the walls. When a chef would finish with a particular piece of equipment, he or she would put it into a sink full of hot, soapy water. About every half-hour, someone would come by to collect the dishes for further cleaning and tidy up, as far as I could tell.

Our guide to the kitchen was Eddie Hales, who has been doing pastry for… a long time. He first showed us the small chocolate room I mentioned. The most interesting part of this was the chocolate transfer sheets he showed us, which you can get a glimpse of in the last picture. Check out some examples of these here. These are plastic sheets on which tinted, patterned cocoa butter has been deposited. (There are lots of different patterns available, some of which seem to be quite complex.)

When you want to use one, you cover the patterned side with a thin layer of melted chocolate. You wait a bit for it to harden, and then you press the chocolate layer to whatever you want to decorate. Then you carefully pull the sheet off. The chocolate, with the pattern facing out, is left behind. You can also just let the sheet fully harden by itself, then break it up to get patterned shards. Pretty neat technology.

Chef Hales also did a pâte à choux demonstration for us. If I remember correctly, he mixed together milk, butter, flour and eggs, cooked the mixture, and put it in the stand mixer. The result was a very thick dough, which the chef piped out onto a tray, and baked. This is how you make e.g. profiteroles and some other puffy desserts, e.g. eclairs.

Asparagus soup, panade and a pear-frangipane tart

Filed under: Cooking Journal — Tags: , , , , , , , , — Justin Dunham on December 21, 2010

The frangipane tart (I don't talk about this until the end of this post, be patient!) before baking...

...and after.

Asparagus soup, with some asparagus tips and feta cheese.

Asparagus soup, with asparagus tips and some feta cheese.

The panade, before baking...

The panade, before baking...

...and after.

...and after.

I read this recipe quite a long time ago, and while the recipe itself sounded interesting, what made me really want to make it was the possibilities.

The link is to a recipe for panade, which is somewhat similar in concept to a trifle, except made with stale bread, vegetables, and cream. There’s a little bit of prep that goes on, but essentially you layer a bunch of vegetables and bread in a dutch oven, bathe it in cream and chicken stock, and bake it for a while. This one has cauliflower, kale (I used collard greens), and cauliflower.

Oh yeah, then you top it with cheese, and bake some more.

By my standards, this recipe is relatively healthy – yes, it includes cheese and cream, but other than that it’s just vegetables. I kind of consider good cheese a health food, though. I acknowledge that this would probably be a controversial view in the evidence-based nutrition community.

Also, as I mentioned above, think of the possibilities! You could maybe do this with beets and spinach, and rye… or some kind of black bread.

I needed a vegetable-oriented first course to along with the panade. This asparagus soup has been on my list for about a year. The asparagus soup is actually healthy, since it’s basically puréed and strained asparagus, together with some chicken stock. I didn’t like this as much as many of my other soups – the flavor of the asparagus doesn’t seem to quite stand up to the flavor of the stock. Also, part of the appeal of asparagus is its crispness and woodiness, which you lose by making it into a soup.

Lastly, and this was the best part, I had a bunch of extra almonds, so I decided to make this wonderful pear-frangipane tart. Wow, this was good. Frangipane in this case is basically an almond paste made with butter and sugar. Very similar, if not the same as, marzipan. It’s incredibly sweet, which I’m normally sensitive to, but something about the almond flavor cuts through this nicely.

We made it from scratch, which involved boiling the almonds for thirty seconds and immediately cooling them down (“blanching”), then peeling the skins off. Blanching‘s a useful technique. It makes it easy (possible?) to peel almonds, and lots of other things too, like tomatoes. It also helps “fix” the color of certain vegetables.

Anyway, after being blanched, the almonds are ground up with butter and sugar. You pour the resulting paste into a pie crust, layer some pear slices on top, and bake. The frangipane becomes a beautiful golden-brown color and firms up nicely.

Beer me, part 3

Filed under: Cooking Journal — Tags: , , , , — Justin Dunham on December 15, 2010

Making the wort from "scratch".

Sanitizing bottles with iodophor.

Completed! We are thinking of calling it "Kirin".

Note: This is a followup to this entry.

Shortly after arriving in Philadelphia, I decided to try brewing another batch of beer with a friend of mine. This time, to save on materials and on wasted beer (yes, it happens), we decided to brew a half-batch.

Brewing in Philadelphia gave us a chance to take advantage of Philly’s awesome homebrew beer scene. The people at Home Sweet Homebrew (see also later entry) have always been incredibly helpful, so we went by there to get the ingredients. They apparently don’t like the homebrew “kits” you can get on e.g. Amazon, like say this one, so they sold us the malt extract as well as hops to be used for flavor as well as aroma. Part of making beer is boiling the wort with the hops in it, which brings the flavor and aroma out. Boiling them for longer increases hoppy flavor, since this is provided by resins that take a long time to extract, boiling them for a shorter time increases aroma, since this is provided by oils that evaporate quickly. Anyway, we added “flavoring hops” at the beginning, and then “aroma hops” at the end of the boil.

I’m a slow learner, so despite this being my third time out, I had to consult the instructions a lot. I haven’t found any quality homebrew instructions by the way – many instruction sets contain confusing, or even contradictory, instructions, which is painful for inexperienced brewers. I attribute this to the inability of most instruction writers to understand a novice’s perspective – they take a lot of knowledge for granted, for example, or give instructions that can be interpreted several ways unless you already know how things should be done. I’m working on solving this problem with some other projects I’m working on, too; it’s an important step to helping people try new things.

Though I am finally beginning to develop a more intuitive sense of how the brewing process works, we still brewed somewhat haphazardly and I think this led to a relatively poor final outcome. As one example, I didn’t realize that all the homebrew shops in Philly are closed on Monday, which was our bottling day. So I ended up having to buy beer (Kirin was the cheapest, sadly) so that we could use the bottles. OK, fine. But we were also out of decent bottlecaps; many had rusted. We tried to use only ones that were clean, and of course sanitized them, but I have no idea if that may have been a factor.

Also, we still didn’t have a good grasp on how important the timing of the various beer stages is (e.g. how many days do you have to / can you wait before bottling?), which again may have caused problems.

On the plus side, I finally learned how to use a hydrometer.

Creative Commons License
.