Shenzhen Blog

This is a collection of blog posts I wrote to document my travels in the summer of 2015. For the most part, I was in Shenzhen doing a hardware manufacturing bootcamp run through the MIT Media Lab by Bunnie Huang, but I made a few stops elsewhere.

The posts are ordered here in chronological order. I was really bad about keeping my blog up to date, so most of these are written far after the fact.

Huge thanks are in order to Bunnie (and Sean Cross and Akiba) for putting together such a fantastic experience. I hope to have done it (some) justice in writing these posts.



Arriving in Shenzhen

Shenzhen Adventure Day 1

The flight to Hong Kong was not bad at all! I think I slept most of the way. On the flight I watched Chappie – definitely go see it if you’re a Die Antword fan.

Upon arrival, I met up with Sean Cross and another student from the program. We took a taxi & the metro over to Shenzhen.

We quickly checked into our rooms and then, after getting frustrated with the internet, I went to sleep.

Shenzhen Electronics Market Tour

Shenzhen Adventure Day 2

I woke up around 7:30AM, although I didn’t have to be up till 9am. Checking WeChat, I saw that another student was up and wanted to grab breakfast at 8am. I responded, then got ready, and then headed out. However, I couldn’t find the other person so I walked around a bit. I was, at this point, phone-less so I had to run back up to my room to check messages and communicate. After finding the other person, we went to a bakery cafe around the corner. I had a really great “french toast bread”. Talking to the other student, it seemed that my internet woes were not shared; indeed, trying her connection yielded great bandwidth, even over vpn. Grumble grumble, I hope I can get mine fixed up a bit!

At 10am we all met up and went to a Japanese super market and got some basic supplies (bananas, instant oatmeal, and soap for me). This place has a lot of Western goods which is very nice, but was a little bit pricey.

We then dropped off our bags back at the apartments and headed back out. We stopped for lunch at a nice restaurant in the mall. I knew eating was going to be really really hard for me, I was pretty worried. If you don’t know about my eating restrictions, they’re relatively simple and I’m basically not picky at all. I used to be vegetarian for a number of years, but I relaxed it for health reasons. Now I try to avoid “sentient” animals. This basically entails to not eating any mammals whatsoever and avoiding other intelligent animals such as octopi or crows. I’m basically fine with any chicken or scaly/bony fish dish. The other constraint is that I keep somewhat Kosher, so I try to avoid shellfish. I made peace with the fact that I would likely have slip ups over the trip. After one meal, let me say this: It’s looking tough. In China, pork isn’t a meat. It’s a seasoning. Almost everything has pork (and a lot of things are probably cooked in it regardless). Although there were a lot of things I couldn’t eat, I ended up being able to have a really awesome ma-style (more on that in a second) fish stew and spicy potatoes. Ma is a special type of peppercorn which is really spicy, but also numbs your mouth so you can’t feel it. It’s almost impossible to get in the States and it is awesome. I’ll have to look into importing some back for personal use. The other really great thing is Tea, the whole meal was cup after cup of delicious barley (I think?) tea. I drank like a gallon of it (although I sweated that out later – Shenzhen is HOT). When the waitress is pouring you tea, you are supposed to knock on the table to say thanks. After the meal, the restaurant is supposed to give you tax voucher slips. I still don’t get this all the way; probably because it makes no sense. Basically, restaurants pre-pay their tax by purchasing these tax-bills that they give to customers. Because they can get reimbursed for over purchasing the tax forms, they would rather not give you them (to under-report taxes). So instead they will offer you a drink at the restaurant in lieu of tax form. To combat this, the government added a scratch off lottery ticket onto the tax slips to incentivize people getting them. To me it seems like a double down on a broken system, but who am I to judge? Definitely makes taxes more fun than the states!

After lunch, we went to hackerspace we’ll be calling home briefly to check it out. The person we needed to talk to was on lunch break, so we went off to do other things. I don’t think words can do the next part justice.

The electronics markets in Shenzhen are insane. There a skyscrapers on which each floor is filled with vendors hawking components. The scale is enormous, and the prices are dirt cheap.

One floor…

Two floor, red floor, blue floor…

Reels of 10,000 components can be had for less than it would cost to buy 5 of them at Radio Shack. There are also these incredible “recycling” markets which take old devices and tear them down and sell the parts. Walking around you can see people sorting parts from devices. When you go to the next floor, they will sell a slightly more put back together version and so on and so forth until you can get ‘new’ devices. It’s hard to explain the bizzareness of these markets. You can find phones, for example, in the shape of soccer balls, cars, miniature iphones, phones with a reading light, phones with massive batteries to charge other phones, and everything else under the sun. I just don’t get who makes the market for these devices given that you never see them, and even the locals seem to not have seen them either. For instance, I picked up (along with several of the other students) the miniature iPhone which runs full android, has 3g, and works quite well except for the fact that it is tiny as hell but locals were just as amused as we all were at them.

Tiny phone, but runs full android and has 3g!

Following the tour of the markets, we went back to the hackerspace, did our errand (getting access cards), and then headed over to dinner with everyone involved in the course. We went to a fancy Chinese Restaurant (that’s what it was called) and had an all out feast with all the people supporting the course, including John Lee (the owner of AQS, a big manufacturing company). This went a lot better for me than lunch, although I couldn’t eat most things, two of the guests were very kind in helping me order some tasty foods – having to explain my dietary preferences is always a challenge, but they were very gracious. I also had to explain some of my other prefernces, but you’ll have to ask me in person for that story!

There is an interesting drinking culture. I’m not sure I fully understand it yet, but I drank a lot of beer and baijiu (a really great shot alchohol that varies from either a sour candy/apple juice taste to pretty close to whisky).

At this point, I started to get pretty tired (as were the other students) so we headed home. I took a quick shower and then passed out for 2 or three hours and woke up to write this blog post. I also learned some chinese expressions that might come in handy tomorrow…

“Wo chisu. Wo ju-ro nieu-ro be-lay guo-mean.”

I am a vegetarian. I am allergic to pork, beef, and shellfish.

Small Bootcamp Update

Shenzhen Adventure Day 3

Today was mostly an “in house day”.

We had a lecture from Bunnie on the course and then we worked on getting our dev environments set up.

Day 4 Overview

Shenzhen Adventure Day 4

Today (Day 4) was awesome, we toured various manufacturers to see the “end to end” development of a device. I’ve broken out the blogposts on each factory separately.

Lunch: We went out to lunch with some of the guys from one of the factories to a local place. The food was great, but a little unfilling as all I had was plain veggies. Luckily, I decided to keep a jar of peanut butter with me at all times so I had a couple spoonfuls in the car for protein. I was most intrigued by eating Gingko in a dish. It’s a kind of “creamy peanut” texture, with a potato-y taste. There were also these guys sitting near us who had the most incredible raspy voices, they were speaking an unknown local dialect and were basically shitfaced at noon.

Dinner:

Jon Lee rejoined us for dinner which was awesome! Of course it meant getting somewhat inebriated again (this time, baijiu and budweiser bombs). Again, they made sure there were plenty of options for me to eat which was great! The restaurant also had these amazing pots of tea, I drank a large volume of that. I was particularly excited to eat a whole water chesnut (never seen them not sliced).

Injection Molding Factory Tour

Shenzhen Adventure Day 4

This was fun! At the injection molder they had a massive pile of not being run molds

and about 20 machines which were cranking out parts. We got to see our mold for the class pried apart which was cool.

Molds are super complicated; I didn’t have an appreciation for how hard they are to make before.

Here’s a run down:

  • Tolerances are ridiculous. They need to be airtight metal with no gaskets so that the plastics don’t leak
  • For nice looking parts, the molds need to be basically mirror finish.

  • Molds can be made from Aluminium for lower cost but they basically don’t do it in China because Steel is cheap enough there.
  • A mold will run about $5000-$10000 USD for a reasonably sized design, and can do about 500,000 casts. This is mostly the price of the steel
  • You can modify your mold by welding on a block of steel and then re-carving out the features
  • Designs with overhangs or other features are much more complicated to build because the mod needs to essentially unfold itself to be able to release a part
  • A mold has a couple key properties, the points where the pins push the cast out and the fill points. Based on these, the finished product will have different flows of plastic through it which could cause different knit points (where two flows meet) or flow lines (artifacts of the plastic’s path). The points where the pins push out are those raised disks you sometimes see on plastic objects.

© 2017 Jeremy Rubin. All rights reserved.