The real purpose for Thanksgiving is the gathering of friends and family in gratitude for the food and company. It may be the purest and most perfect holiday we have.
Last Monday evening we were lucky enough to attend a fine Thanksgiving dinner with friends in the city. The food was excellent and the careful orchestration in the kitchen and service caused my mind to wander...
What if food could be used to describe 3d printing?
Presentations could be mind-bogglingly complicated and would be perfect down to the millimeter. Chefs could describe any presentation they could imagine, exchange their presentations with other chefs around the world possibly making a bit of money on the side. Home cooks could have machines in their kitchens and reproduce anything they could afford. The amount of preparation time would be well-known making it easier to bring all of the dishes in a dinner together at the same time. Experimenters could create designs on their computers and know how they would turn out in advance. Neat, but there is a nagging problem ...
Materials
Three dimension printers can only deal with a limited palate of materials. To make the analogy with the current world of 3d printers imagine machines where one model could only deal with a four varieties of cheese. It might be very good with cheddar and less good with three other hard varieties, but no other cheese would work with it. Another printer might be very good working with ice while still another model does a fine job with frosting. The cheese model allows you to print with colored cheeses and that feature will be added to the frosting model sometime next quarter. There is a home model planned based on a hobbyist kit that can print spam (the stuff from cans rather than the email variety).
Materials and how they are treated during manufacture are really important!1
Most of us don’t think about it much, but consider the thousands of fabrics used in clothing, the complexity of materials that go into food, the hundreds of different woods used in building, the thousands of materials at an architect’s command when a building is designed, the exotic materials of a turbine blade in a jet engine or that make up one of the billions of transistors in your phone.
A good designer needs a fundamental understanding of the materials used in their domain.
3d printing is still very primitive. It has enormous value fabricating prototypes, but there isn’t much flexibility in material choice. It is like living in a culinary world limited to spam, icing, hard cheese and ice.
Some disciplines push material use and design more than others. Bicycles and airplanes are among the most interesting as the final vehicles should be strong and lightweight. The bicycle is particularly fascinating as it is both elegant and simple. It is still possible for a single designer to make most of the choices alone rather than relying on a large design and engineering team. Airplanes were once that simple - when two bicycle mechanics from Ohio created the revolution, but the sport now requires large teams.
At about three to four times as efficient as walking, bicycles are the most efficient way to move a person using only muscle power. There isn’t a lot of material, but a frame can be very strong often support fifty or more times its weight. The shock of uneven roads is absorbed without losing much efficiency while the bike is rigid at the same time. The drive train can transmit as much as 98% of the power you supply to the wheel and simple brakes that weigh a few ounces can dissipate the energy of a racer flying downhill at 50 miles per hour in a few seconds. All of this is done by a machine that can be beautiful. A bike is one of those places where art and technology come together.
Twenty years ago most bicycles had steel frames. The type of steel and construction technique used were a function of the cost and purpose of the bike and high end bikes like my old Raleigh Professional were made of hand brazed exotic steels like Reynolds 531. This made them light for the day and imparted a certain signature quality to the ride of the bike.
About then bikes with aluminum frames started becoming practical. Aluminum has very different characteristics than steel and was difficult to manufacture, but Trek and others started using hydroforming techniques and prices dropped. The bikes could be lighter than equivalent steel frames, but the ride quality was different. Some of us preferred high quality steel, but there was a choice.
China builds an enormous number of bikes and began to export them. A decision was made that bike technology is strategic for China. Learning how to make aluminum bikes was seen as a way for China to dominate the international bike market as well as learn how to world with leading edge aluminum fabrication techniques. What works for bikes also works for airplanes and thousands of other products.
The first Chinese models were awful. but they stuck with it through partnerships and got to the point where they pioneered some techniques of their own. in large quantities a low end bike frame from China now sells for about $4 - probably less than the cost of the electricity used to make the aluminum in many parts of the world. China may be losing on the frames, but they own the market and make enough other high value parts to end up winning.
Now they are working on reducing the price of carbon fiber.
Carbon fiber is found in most racing bikes. I’m not fond of its ride quality, but it is stiff and very light. It is possible to make a frame that weighs under a pound with a final, albeit exotic, bike tipping the scale at under ten pounds. The Union Cycliste Internationale responded to this by requiring bikes to weigh at least 6.8 kilograms - about 15 pounds. The bikes are lighter, but carry some electronics now. Racing is an arms race in many dimensions.
Good carbon fiber frames are difficult to make with a large amount of labor and high material prices. A few years ago a reasonable frame might start at three thousand dollars and unless your name was Lance Armstrong, fabricating one to exact dimensions was usually not practical. Now the price has fallen by about an order of magnitude as, once again, China has determined that carbon fiber fabrication techniques are a strategic need and a good are to gain focus and experience is the bicycle industry. Such techniques have great application in aviation, wind turbines and will become common in the automobile industry during this decade. it is possible the scale of the carbon fiber industry dwarfs the automotive battery industry.
But back to the basic bicycle. It is possible to make bikes from other materials. Titanium has desirable characteristics, but is expensive and difficult to work with. Bamboo can be used by itself or as a composite material and can create beautiful bikes with a ride quality some people find wonderful. And cranky purists like Dave and I have a variety of steels and techniques to chose from.
About two years ago a special bike was created for Colleen - a good friend who happens to be approximately tall. Her body happens to be beyond the limits of the CAD tools common to bike design and a careful bespoke design was called for. It was decided to base the design on an upright commuting bike rather than a racer and ride quality was important. The issue was the frame was so tall that to get the right shock absorption, rigidity and “feel” the steel tubes used had to be carefully tailored. The project required carefully measuring her with the precision normally reserved for racers. This made sense as it was an entirely new design. The steel was Reynolds 953, an exotic stainless steel requiring unique manufacturing techniques. There is only one company on the planet that can make this stuff. The wall thickness on the tubing is very thin - less than a half mm and as little as about a third of a mm - with tubes being carefully matched to produce the right ride quality. It isn't cheap at something like $100 a linear foot, but it allows some interesting designs.
Jony Ive at Apple showed the world that consumer products can become art when mixed with great design and an informed materials choice. My MacBook Pro has a body machined (!) from a single piece of aluminum stock. An expensive process, but the quality shows and laptops from other manufacturers feel like toys to me even before the machine comes to life.
We live in a material world that is not made of hard cheese, frosting, ice and spam.
As it is Thanksgiving eve it makes sense to finish with a recipe that celebrates the enormous amount of material and fabrication choice available to the cook along with a bit of simplicity.
On Monday we had some excellent roasted asparagus as part of an early Thanksgiving dinner in the city with friends. There were asparagus dreams that night andI had to make some on Tuesday.
I usually make asparagus when it is in season, but roasting gives you a bit of latitude and if you are willing to sacrifice a bit of the produce, you can still get great results. I bought about a pound of ok looking stalks yesterday and fired up the oven. The warning is the measurements are guesses as I cook mostly by throwing things together. (baking is where I’m careful)
• Pre-heat oven to 400° F
• Snap off the bottoms of the stems at the natural breaking place (I used these for asparagus soup later, so they aren't wasted). These weren't great asparagus, so I peeled the bottom inch or so
• Put on a baking sheet, drizzle on some olive oil. Add a bit of a good sea salt (Maldon for example), grind some pepper and toss. Now arrange on the pan so the stalks aren't touching.
• Bake for 20 minutes and plate
• Melt a half ounce of butter and add 3 or 4 chopped cloves of garlic. Heat until about the time the butter starts to brown. Drizzle/spoon or whatever over the asparagus (note - the heart healthy way would be to use olive oil here. I strongly prefer butter and rationalize it with the idea that each of us is only getting a quarter ounce.
• Sprinkle with chopped pecans or walnuts
• Squeeze a bit of lemon juice on top or a drizzle good aged balsamic vinegar.
Happy Thanksgiving!
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1 I note that 2d printing is just cutting flat objects and technologies abound that allow a great choice of materials. We will see, and are seeing, dramatic change here well before 3d printing becomes important outside of a few niche markets like prototyping.
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