It’s funny how the title is sort of a spoiler for the episode. Right?

DIY Safe Cracker

This is technically a MacGyver-hack since it’s from MacGyver, just not from Angus MacGyver.

The basic idea is to open a safe with a dial on it. Instead of trying to figure out the lock combination, a robot can just try EVERY combination. This is called a brute-force hack since it’s not elegant but it works.

Oh, you want to build one of these yourself? You are in luck, here is an epic guide. https://learn.sparkfun.com/tutorials/building-a-safe-cracking-robot

Also, here is another brute force hack (on a key code door).

Book Cipher

I’ll be honest. I had no idea how a book cipher worked. But with a little help from the internet, I finally figured it out. Here’s how it works.

• You take some text that you want to send. The example I use is the word “cat”—yes, that’s sort of silly.
• Next, you need to convert each letter to a number. I’m using the ASCII UTF-8 format to convert each letter to a hexadecimal number (base-16 numbers instead of base 10). For “cat” this would be 43 41 54.
• Now I take a word from my “book”—in this case it’s a take out menu from a Chinese restaurant. If I use SPR (from spring roll), I can also convert that to ASCII to get 53 50 52. This is my key.
• Now I add my text and my code to get 96 91 A6. REMEMBER these are hex numbers, so you have to add them differently than you would with decimal numbers. This gives me the code—this is what you send.
• To decode the message, you just do the opposite.

Here is a longer explanation with a video.

Just for fun, here are some of my notes along with Oversight’s calculations on the dashboard.

Fuel Pump

MacGyver needs to transfer fuel from one car to another. Here is a very cool pump.

The key to most of these pumps is a one way valve. You need to make something so that water can flow the way you want to pump, but not the other way. Here is a very simple way to make a one way pump valve with a turkey baster and small ball.

Belt Handcuffs and Bolo

Really not much to say here—normal MacGyver stuff.

Ascender Rig

MacGyver and MacGyver build a device so that they can get on the roof a building. Yes, it’s an ascender rig. It’s basically just a battery (a car battery in this case) and an electric motor. The motor winds up a rope and causes the whole thing to move up.

Here’s the cool part. You could really do this with just about any electric motor. Yes, even that tiny weak motor could still lift two humans. The only difference would be the speed. If you get the gear ratio right, this tiny motor would slowly wind up the rope and just take longer to get to the top.

Spark Gap Generator

The spark gap generator was the first type of radio transmitter. When a spark is created, it also produces electromagnetic waves (over a broad range of frequencies). That means you can’t really have radio channels, but you can indeed send a signal.

If you want to know more about spark gap generators, here is some info. I even built one mostly from scratch.

https://rhettallain.com/2018/12/14/adventures-in-spark-gaps/

But could you make a spark gap generator with a magnetic stirrer? I think so. One of the key things you need is a changing electric current. If you use the spinning stirrer, it can make electrical contacts at different points during the spin. Here is an example.