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Father Robert Ballecer: On this episode of Know How, we are on a mission from Gad.
Fr. Robert: Welcome to know how. It is the twit show where we built, bend, break and upgrade. I’m father Robert Ballecer.
Bryan Burnett: And I’m Bryan Burnett.
Fr. Robert: And for the next 45 minutes or so we are going to be showing you some of the projects that we have been working on so that hopefully you can take that knowledge back and geek out on your own. Does that sound about right?
Bryan: Yeah, that’s what we shoot for every week.
Fr. Robert: That’s what we shoot for but we never get there.
Bryan: Will see what happens.
Fr. Robert: For the first story I actually wanted to talk about something that isn’t so exciting. Over the weekend Verizon announced that all of their plans are going to go symmetrical. So if you are one of the very lucky few who has files, their fiber to the door Internet plan, you will now have full speed in both directions. So for example, if you had their 15 Mb per second down and 5 Mb per second up, it is now 15/15. Same goes for the 15 Mb plan and the 75 Mb plan. Now you can get the same speeds in both directions. This is what I like, Bryan. This seems to be a direct response to the fact that Google in their Google fiber project is offering symmetrical speed. It is 1 Gb per second in both directions. In the past ISPs have been very reluctant to offer this because they said people just don’t use it.
Bryan: That might also be because they didn’t have any competition.
Fr. Robert: But even when we talked about this show on my network show on Monday, people in the chat room or saying I don't use uploads why do I care? But, think about it. How many times do you upload to YouTube. How many times do you upload your photos. How many times have you ever wanted to be able to backup all of your computers to the cloud really really quickly. That all requires optimum speed.
Bryan: And that is important to us too on Skype.
Fr. Robert: Absolutely if you do any video conferencing upload is the limiting factor. It's not the download. As we can attest to hear in the brick house. It is always that link coming back to the studio this seems to get trashed
Bryan: I think the connection we have here is Comcast and it is 100 Mb down? It is fast.
Fr. Robert: Here is the thing. Even if you are not doing any of those things, even if you don’t upload to YouTube, even if you don’t back up your computer is to the cloud, even if you don’t video conference, you still need upload speed. Remember a few weeks ago we were talking about ports? And how there was TCP and there was the UDP. UDP is sort of a shotgun approach. I take all my data I put it in the package and I send it out and that’s it.
Brian: If it gets there, it gets there. If it doesn’t, who cares.
Fr. Robert: TCP is actually the communication protocol that most of us use more often. That is two way because the receiving side has to verify that they received the packet and that everything is there.
Bryan: There is more overhead to that.
Fr. Robert: And there is also more back-and-forth talk. So even if you don’t video conference, even if you don’t podcast so you need to upload to YouTube, your Internet speeds will still increase if they are no longer choking your upstream side.
Bryan: Absolutely. I am all for having fast upload speeds but I kind of have to reserve my judgment because I don’t have Verizon, it is not really available here. But also there is that article that came out about the guy who bypassed Verizon because they were throttling Netflix. So it is like, great, you have symmetrical and that’s better, as long as Verizon lets you use it for stuff.
Fr. Robert: That is the ultimate thing and that is what gets me more excited. It is not the fact that it is symmetrical, that is cool from a network geek perspective, it is the fact that Verizon seems to be reacting to Google. I like that.
Bryan: Finally there is pressure being put on the ISPs to get faster Internet so I can do stuff.
Fr. Robert: And if Verizon and Comcast and Time Warner and AT&T start saying we better start offering these things to our customers, otherwise I’m going to go someplace else, that can only be a good thing.
Bryan: Right, and without the competition they can just kind of bowl you over. And say, here is this triple play plan that you might want to do. If Google could come out here for a little while? But I don't think it’s going to happen. I remember a long time ago, I won’t say his name, but a Google employee came in when I first started working at the brick house and he said if the other ISPs don’t play ball Google is going to put pressure on them. And that was right before they announced they were going into Kansas City. So, Google fiber, thank you.
Fr. Robert: Comcast has also announced that they are going to go symmetrical but instead of speeding the uploads they are actually slowing down the downloads. No, they’re not. I’m kidding. Now Bryan, we sent you out with a very specific task. And that was to do this NFC theme.
Bryan: Right, well Tony came to me because he wasn’t really sure what NFC did or what you could do with it. But to explain that, to start with let’s start with the basics. NFC stands for near field communication. As you would imagine that means that is a very short range of communication, like within an inch. It is a standard used by a lot of devices, mostly smart phones you see are NFC incapable. So today I wanted to show what you can do with some NFC tags that I got off of Amazon for about $10. But before that I should say that NFC is based off of RFID which I know you’ve heard it. Radio frequency identification, which uses electromagnetic induction to transmit information. So, if you have ever used a bus pass or something like that if you have public transit, it is the same sort of principle.
Fr. Robert: The important thing there is that you don’t need a battery in the client unit. So for example your bus pass that was using RFID, it actually gets its power from the reader. It receives a little bit of wireless power, and not forget to send that radio signal that includes all the data that it is supposed to give off and will message you back. NFC is the same idea it is just much lower power and much lower range. The problem with RFID was as we figured out, you could read it from a long distance if you have the right antenna you can start picking up people's RFID. So NFC was created to give you something that is basically contact. You have to be within the very short range in order for NFC to set off.
Bryan: And when you are using two devices like to cell phones, one will be active for sending information and the other one will be passive as it is receiving information. But when you are doing this like if we send an MP3 or a picture they are both active. The den, like you were saying these tags are passive and there is no battery or anything like that that they can receive and transmit data. So, let’s see. Oh and also another example is Qi, the wireless charging system. Is also based on the same principle as NFC.
Fr. Robert: It is prolonged transmission that the client device can turn into charging power. And actually that is what this does. This supports that. So if you take the backing off of this phone there is actually a quail inside this back cover that can receive that energy and then it charges the battery on the phone. So this is a Qi device.
Bryan: that is what I wish my Moto X had. Maybe the next version. But then the other mode that you can do with NFC is read right. So when you pick up these old tags, these NFC tags you can download an app off of the Google store. The one I decided to go with was just basically called NFC tools. And there will be a link for that later in the show notes. So I have actually programmed these two chips to do something different. Inside the app, you can approach an NFC tag and see what information it has on it. So now I am looking at all the information that is saved on this tag. And it is writable, it can be read only and it says it has a record on it. But say I wanted to add a task to my tad. These are helpful for if you wanted to do something in your car, like if you wanted to turn on your blue tooth and have it play music when you are going to get into your car.
Fr. Robert: You can have an NFC tag trigger a specific sequence of events. Which is nice, for example I’ve used NFC tags to give people the Wi-Fi pass for my house. As you come into my house there is a little tag that says tap here for Wi-Fi access. And when they tap their device it will give them the encryption pass for the guest network. It is a lot easier than some saying what is your password?
Bryan: That makes it a lot simpler. If you really want to get nitty-gritty, Russell was talking to me about his home automation step that he has been doing. And there is a another app called Tasker which really lets you get into it. He has actually got it set so that he has lights come on in his house when he taps it and things like that. You can get pretty crazy. But we are going to keep it basic for today. Once you have downloaded NFC tools you will also need to download this extension called NFC tasks. That is just an add-on to the app that allows you to use NFC to trigger tasks. It doesn’t really do much other than just let you do that task.
Fr. Robert: But you get to set the task, which is nice.
Bryan: Which is the whole cool thing about it. So say I have an empty tag. These two I have already programmed to do something that I will show you in a second. So, when I go to tag, tasks, add a task. There is a whole list of different things you can have your phone due to be triggered by it. So what I want to do first is I’m going to have it launch an app whenever I tagged this. So let’s say I sit down at my desk and I always open a certain act when I sit down at my desk. I always played by Bike Race when I sit down at my desk. Because I’m not going to be working. So it lists that, and you can load more than one thing. You can actually do multiple things at once. So I want to load that app and not only that I want to make my display brighter as soon as I sit down. So I will set the display brightness up and what else can we add. Let’s change our sound. Let’s make it so there is no volume Because I don’t want anyone to hear me play bike race when I sit down. So I have three things that are going to happen when I write to this tag. That is about 96 bytes which I think is about all. There’s not a lot of space in a tad. It is very limited. But you can stream quite a few things together. Me and Alex were writing text messages back and forth between each other on them. So now I can write to this little tag. So now I go back to my home screen and I’ve noticed on android that you do need to be in an unlocked mode.
Fr. Robert: That is a security thing. They don’t want someone writing a malicious tag.
Bryan: Make sure that you are not in your lock screen and then if I tap it, it has lowered my volume, it is turning up the brightness, and now it is launching Bike Race.
Fr. Robert: Nice.
Fr. Robert: Have done it to daisy chain, those three events. But they could be anything. For example, it could be in Russell’s example that let’s say you have an NFC tag on your nightstand. You put it on your nightstand and your phone knows to turn brightness all the way down, turn off all sound, turn off alerts so you don’t get the blinking light and set an alarm. And talk to the home automation system to turn on the lights. That is all programmable within the interface for the NSC program.
Bryan: So that is something that I have been playing with. If you order this pack that I have been playing with, you get all these cool stickers too.
Fr. Robert: Which by the way, if any of you play Ingress, join the resistance.
Bryan: To finish up with the NFC, in later episodes I will come up with other streams that you can tie together for NFC tags.
Fr. Robert: What I would love to do is combine that with a key charger. So that you can charge and activate a bunch of things at the same time. That would be my perfect nightstand phone docking station. Charge, and turn everything off.
Bryan: And in this NFC tools app you can really drill down into stuff like you can have Bluetooth be toggable, where if you tap it once it turns it on and if you tap it twice it turns it off. so if I got in my car and I wanted Bluetooth on, or if I'm getting out of my car and I don’t want it on or Wi-Fi and GPS. I noticed that you can’t turn on GPS or put your phone into airplane mode without root access. I guess that is an android security thing. So there are some pros and cons to NFC but the big one is that it doesn’t require a power source for passive devices. So you can just stick these somewhere and you don’t have to think about it again. You just tap your phone to it. Some of the drawbacks are the range is just about a few inches.
Robert: Which is actually good.
Bryan: And the transfer speed is a lot slower than something like Wi-Fi or Bluetooth. But, you are not going to be really but if you ever use android beam or S beam on Samsung phones what that does is it uses NFC to start the pairing. And then it launches into a direct Wi-Fi mode and that is how you are able to transfer bigger files and stuff like that. So it is pretty nifty.
Fr. Robert: You should mention that because a lot of people are saying oh like transfer via NFC. No you kick off the transfer with NFC that it uses different technology either Wi Direct or Wide Eye or Bluetooth. Some of these actually transfer over cellular networks, which is strange, but it is a roundabout way.
Bryan: So, yeah. I've been having fun with these tags. I think what I am going to do for myself is that I’m going to put one on my motorcycle. I want to do that because motorcycles are dangerous. I agree with that. But, I want to alert certain people that I’m writing my motorcycle. So someday when you don’t hear from me for a few hours well maybe something happened. So I am going to have it send a text message to my wife so she knows that I am riding my bike. But I am thinking about tying it in with, if this then that. So when a tag generates a check in or something like that I will have if this, then that also tag me in it.
Fr. Robert: You could also put one in your seat on your bike.
Bryan: There was a demonstration video that we did a while back between here at the twit studios, can we play that thing? How to secretly send messages using NFC. We weren’t supposed to show the whole video.
Fr. Robert: You were married right?
Bryan: That was in my wild bachelor days. Transferring NFC files willy nilly. Have some fun with NFC! We did. Certainly not rewardable at all. Enough about NFC. What if I wanted to fix stuff?
Fr. Robert: When we come back we are going to be talking about Project Lunch Box. will we were going to be assembling a remote-control buggy that there is a couple pieces of technology that you should know about before you assemble your own. Speaking of assembling your own, do you know one of the best ways to assemble kits is?
Bryan: Having tools that you need for it.
Fr. Robert: Exactly. The proper tools are absolutely necessary if you are going to be assembling a kit. There is nothing that is more frustrating than starting a project and realizing you don’t have the tools to complete it. Were even worse, not having the right tools. Everyone has a screwdriver. Everyone has a pair of tweezers. But do you have a screwdriver, do you have the tweezers, do you have the kit to work with electronics on a small level? I fix it does. I fix it is the premier spot to go when you want tools. iFixit is a free online repair manual for everything. And not only that, they have these tools. The iFixit toolkit that allows you to fill out the step that you see in those manuals. They have more than 10,000 repair guides for everything from electronics like your smart phone, tablet, games console to your home appliances, your clothing and even your bike. They also have foolproof instructions to fix all your stuff. If you shattered your iPhone screen, if you need to repair the red ring of death on your Xbox, or swap the battery on your galaxy S3. iFixit has got you covered with parts, tools, and repair guides. I fix it also makes the most trust worthy repair tools for consumer electronics including the ProTech toolkit. Now this has 70 tools to assist you with any malfunction or misfortune that comes your way. The toolkit is the gold standard for electronics work, for garage hacking to the CIA and FBI. But more importantly, their unique tools are used by repair technicians everywhere. Now this includes iFixit 54 bit driver Kit. It has 54 standard specialty and security bits, including Phillips bits works and torque security bits, tri-wing bits which is more popular on video game consoles and triangular bits which are for McDonald’s toys. So if you ever wanted to hack apart a McDonald’s toy there you go. I fix it can also be used maliciously if you have a cohost that wants to break your stuff. They've also got that swivel top precision driver which allows you to reach into difficult and hard to get places. And the flex extension right here for those projects where you need to get around corners. Have you ever tried to tighten a fastener and you don’t quite have the space? That is what this is for. To get around that hard bend and continue your job. It also has DSD precision tweezers for delicate manipulation and antistatic wrist strap which keeps your device stayed from accidental discharge, nylon spongers, metal spongers and plastic opening tools for prying, scraping and the like. It is lightweight, compact and durable and has this tool roll that makes it on the go for repair professionals and amateurs alike. It is only $64.95 and it is backed by a lifetime warranty. We swear by this kit and you should too. Now, here is what we want you to do. We want you to try iFixit. With iFixit you can fix it yourself and iFixit can help. Try ifixit.com/twit for more than 10,000 free step-by-step guides. iFixit also sells every part and will that you will need, we have used them extensively for our repairs. Enter the code know-how at checkout and you will save $10 off any purchase of $50 or more. That is and we thank iFixit for their support of Know How.
Bryan: You don’t mind if there is… I’m just going to leave it there for you. You have two of them, you don’t need both of them do you?
Fr. Robert: This one kind of broke.
Bryan: Actually I’m going to be using this kit for Shannon’s Nexus 5 that broke. I need to fix that. Hopefully by next week I’m going to do that.
Fr. Robert: Good. That is a nice little project for people like you. Didn’t you break it?
Bryan: No, that was the Samsung S4 active that fell off while I was riding. But anyway, there is only so much stuff you can fix.
Fr. Robert: Okay let's talk about differentials. If you have done any sort of auto repair and you have heard about it differential. If you have ever played with a remote control vehicle, if you have read through the instructions, you have probably read about a differential. But a lot of people don’t actually know what a differential does. Imagine this. And imagine you have a vehicle that has gearwheel drive. And so the rear wheels turn to repel the car forward. In fact we had a little example here. we’ve got our project lunchbox so here is the front of the car. If it is traveling, the rear wheels are going to move at the same speed right? The problem is, what happens when it turns? When you turn, the outside wheel has to cover more distance. So it actually has to rotate faster.
Bryan: In the inside has to go slower.
Fr. Robert: If you have the two drive wheels going the same speed as you are trying to make the turn it kind of fights each other. Either the outside wheel will kind of have to hop, or the inside wheel will have to spin in place. It is a horrible for handling. So we created something called the differential. All that it does is that it allows for differential rotational speeds of the wheels. That is what this does. It allows the wheels to rotate at different speeds from one power source, which is actually very important. Let me explain that. This is what a standard differential looks like Inside of a car. The idea is that you have power being applied to that big gear which rotates those two small gears, though small gears are engaged with the driveshaft. So as you can see, as the vehicle starts to torrent one side will turn more quickly. Now how that is governed is determined by what kind of differential it is. The first type of differential is what is called an open differential.
Bryan: Is this the most common differential?
Fr. Robert: This is the most common because it is also the easiest to maintain. It is the cheapest to put together. The idea is that the power goes to the shaft, to the gear with the least resistance. The power follows the path of least resistance. Which is good, because it is cheap. The problem is, as you can see here is that if you are on ice or for example here if we high side this car…
Bryan: All the power is going to be going to the wheel that has no resistance. So it is stuck.
Fr. Robert: So again. Very inexpensive, very easy to maintain but also not great. It is, for very cheap applications because if you high side yourself all the power will just spend away because that is the path of least resistance.
Bryan: Not so great for burnouts either.
Fr. Robert: Horrible for burnouts.
Bryan: The nickname for my first car was the one we’ll wonder. Because I could do a burnout and just one will would spend so the whole passenger side would be smoky.
Fr. Robert: But that one wheel would spend my crazy because all the power went to it.
Bryan: Honda Integra.
Fr. Robert: Now we know why you write a motorcycle. There is a second type of differential. The second differential tribes to solve the problems of the open differential. So the problem with the open differential of chorus is that since the power always goes to the path of least resistance, if you have one wheel that has no traction all the power is going to go there. Which is counterproductive. In limited slip differential it changes it. It uses a method, either electronic or with breaking or hydraulic. For example, if I put a brake on the wheel but is spending the power has to go to the other wheel. If I have a hydraulic system that guarantees that some power is going to the other wheel that is another way of doing limited slip. Or, as we do in RC cars it is kind of a clutch. You have two plates on top of the differential gear that has all bearings in it. The tighter you make those plates, the more power it will supply to both wheels no matter which is the path of least resistance. A limited slip differential will guarantee that at least some of the power will go to the wheel with the most traction.
Bryan: I’ve heard in the past that LSD’s are more of a sporty car thing. Something that you would find in a sport car?
Fr. Robert: Everyone has LSD’s. All cars today have some sort of limited slip differential. That is a safety feature. Just because you don’t want one tire to suddenly spend. That is a bad thing. So all cars today will guarantee, in one method or another, electronically, hydraulically that some of the power will go to the wheel with the most traction which means it will always move you forward, which is good because if you keep your forward momentum you will probably get out of whatever situation caused you to lose traction in the first place.
Bryan: Okay. But there is one more isn’t there?
Fr. Robert: There is one more. And the third one that we want to talk about and that you will see on RC cars is called the locking differential. The idea of a locking differential is that you have some sort of mechanism that eliminates the differential. It locks it. So that power is being distributed equally to both tires no matter what. Which essentially defeats the purpose of a differential.
Bryan: Right, because if you are turning with a lock differential does that mean one wheel won’t spend? They will both span at equal?
Fr. Robert: They are going to spin at equal speeds. Which means you get back to the power problem that it doesn’t want to turn. But it is incredibly popular on four-wheel-drive vehicles. Because if you have ever been off road you don’t want wheels to spin. Also a locking differential helps with the torque. It gives you tons of low end torque. So let's say you are rock hop crawling you want the differentials so that all four wheels are rotating at the same speed.
Bryan: So for wheels can be up in the air but you are still getting power to the ground.
Fr. Robert: So even if you’ve got two wheels that are suspended, you are still going to get power from the remaining 2 wheels on the ground. Again, horrible if you want to turn. But great if you just need traction. If you just need to push through. Most locking differentials systems have some sort of automated way to disengage the lock. It used to be when I was growing up there was a lock. You actually had to get out of the car and turn these locks on the wheels to lock the wheels into place. A pain in the butt. And not really practical. I think someone is going to correct me in the chat room but I think it was the Jeep Cherokee that first introduced in cabin locking. There was a button you could push that would lock the differential. The problem with that was that people didn’t read the manual and it said do not engage the locking differential while moving. And people would be on the road and say what is this button? And you would hear this horrific noise and then the diff light would turn on, you could still drive but you wouldn’t be able to lock it anymore.
Bryan: I feel like that needs to be one of those buttons where you put two keys and at the same time to turn it and you have to flip up the glass and push the button?
Fr. Robert: I have a cousin who was a mechanic and he was talking about that. He said we call that button money. Push that button and we get money. If you were stupid.
Bryan: Okay. So that is the three kinds of differentials.
Fr. Robert: That what we are going to be dealing with. So when we start building, we are hoping to continue building models. It is a great way for you to learn about technology, but on a smaller scale. So in this model we have learned about motors, we learned about power trains, we have learned about how servos work and now we are going to learn about transmissions. There are so many different types of transmissions. This one is relatively inexpensive, but we hope to show off some limited slip and locking differentials in the future.
Fr. Robert: Now, when we come back we are going to be showing you how we have built the transmission stage for this. How we actually put all the gears to gather and started to get our lunchbox project a little bit of power. But before we do that, I’m kind of hungry.
Bryan: Oh, did you bring some snacks?
Fr. Robert: We need some snacks. One of the things that you may know that I do is I eat. A lot. Unfortunately I eat mostly unhealthy stuff. There are a lot of snacks that five for my hunger and unfortunately chocolate and sugary treats often win out.
Bryan: Well they are not good for me either, unfortunately, Padre.
Fr. Robert: But, what we’ve got is Nature Box. This has been an instant hit in the brick house. Because what they do is that they give you healthy snacks. Non-sugary, non-nasty snacks that you can eat better healthy. Everything is from flax seeds to… where are those Santa Fe corn sticks? I think those are all gone.
Bryan: Every time those coming on I see them stashed in your desk. It would be nice if you would share them.
Robert: I have got
about five bags of the Santa Fe corn sticks because they are just really good.
It has no high fructose corn syrup, it is going to
give you what you need for your dietary regimen.
Bryan: You can drill down to the things that you want in your snacks.
Fr. Robert: They’ve got zero trans-fat, they’ve got zero hi fructose corn syrup and there is nothing artificial. Now, nature box sends great snacks right to your door with free shipping anywhere in the United States. This is how it works. We click on the continue button on the webpage and we get to choose between three subscription options. And then we place our order. Once we became members we were able to select the snacks that we wanted in our monthly box. You can select by dietary needs, for example if you are a vegan or soy free or gluten conscious or lactose free, nut free and non-GMO. You can also select by taste, which is something that I never did. You’ve got a savory, sweet, and spicy. Those are distinct flavors. I always just thought snacks or snacks but sometimes I am craving the spicy and sometimes I want something savory and I’m always looking for something sweet.
Bryan: I may have told you last time when we were doing nature box that I am a diabetic and sometimes I need snacks, but I don’t want to binge on potato chips or candy.
Fr. Robert: They had roasted peas. Those were really good. Almost like corn nuts but not corn nuts. I love them.
Bryan: I noticed how a lot of those disappeared. It is so weird, that we can’t find those anymore.
Fr. Robert: The next time you get cranky and hungry than come by my desk and go ahead and pick up a pack of nature box snacks. Now the one that Leo likes are the guilt free coconut date energy bars. Those things are really good. They are also never to be found. He’s got those. I’ve got the Santa Fe corn sticks, Josh wanted to take that’s a sirachi cashews.
Bryan: And give them to his bird?
Fr. Robert: He said he doesn’t eat milk.
Bryan: But I’m sure if he did want to smack that he could find something.
Fr. Robert: Here is what we want you to do. We want you to try Nature Box. See if they might be as good for you as they are for us. Right now you can get 50% off your first box by going to naturebox.com/twit, stay full, stay strong and go to naturebox.com/twit. We thank Nature Box for their support of Know-How.
Bryan: I’ve got to hang on to this. This is not going to your desk.
Fr. Robert: Now we need to bring you into some of the more intimate parts of project lunchbox. Take a look.
Fr. Robert: Most of the tools you’ll need to build the lunchbox are packaged into the kit. You will need a screwdriver, a pair of snips, and may be as set of needle nose pliers. The kit comes with a set of detailed instructions and all the parts from the screws and bolts to the gears and plastic pieces, they are labeled and bad. So you should be able to assemble your model as long as you don’t skip any steps. Each step includes a lettered number code so you know which parts to pool, but we are going to give you an overview of what assembling the transmission will look like. The first thing you will need to do is to snip the transmission housing from its plastic holder. Try to cut as close to the transmission’s outer surface as possible without cutting material out of the transmission shell itself. Later, you can take and X-Acto knife and carefully trim away any remaining plastic chats. The kit comes with a bag of my long rest were sleeve bearings. These will work just fine. But if you want a little more longevity from your model, and significantly less friction in your drivetrain, spend $15 to get yourself a set of metal ball bearings. These ball bearings will be used anytime there is a shaft that must spend freely in the transmission case. Each half of the transmission has a chamber that will house and position the drive shaft with that wheel. You will need two ball bearings for each shaft. To properly support the weight to promote free spinning. You can see the bearings with just your fingers or use the back end of a screwdriver to lightly tap them into place. The two drive shafts are the thickest pieces of steel in the kit. Each has a threaded receiver on one side and a hack snuck on the other. There are two beveled gears in the kit and each with a hexagonal cutout that will allow the driveshaft to mate with the gear so the assembly can spin together. Because of the layout of the gears in the transmission, the shaft in the right half of the transmission will need to be slightly spaced from its ball bearing. A small metal sleeve slides over the shaft to provide the proper standoff. Once the beveled gear is made into its driveshaft then the right side shaft has its space or, they can both be inserted into the respective halves of the transmission case. Give each shaft assembly a few spins to make sure there is no binding and that they spin true. Let’s talk about lube. Lube is your friend. A small tub of grease will be included in the lunchbox Kit. It should be applied to all the gears, shafts, and moving parts. A thin film will be enough, anything more is counterproductive. Also remember that you’ve got balled bearings on your shaft so you don’t need grease to reduce friction between what would have been the shaft and a plastic sleeve. With a beveled gear and a driveshaft installed, we now need to install the counter gear. The 50 tooth side will make contact with the motors pinion gear while the lower geared side will turn the differential gear. Since we want the gear to turn with as little friction as possible, we need to install two more ball bearings into the inserts on the gear itself. Note that one insert is smaller than the other, your ball bearing kit should include one slightly smaller ball bearing. This is where it goes. The differential gear is an interesting assembly because it has three beveled gears at its center. You install the beveled gears using three small rods. Once the beveled gears are in place, the differential gear will be sandwiched between the two large bevel gears spinning the driveshaft, creating an open differential. Turning the differential gear will rotate the small bevel gears which will be engaged with a large bevel gears which will turn the driveshafts. Driving the power towards the shaft with the least resistance. A small pen goes through the differential gear into small receivers at the end of each driveshaft to keep the gears aligned once the transmission case is closed. Start final assembly and the right half of the transmission. The counter gear goes in the side closest to the wall. Then the large bevel gear goes above it. The differential gear is seated on top of the large bevel gear, make sure that the shaft to the differential locks into the receiver on the driveshaft. Also make sure that the teeth of the differential gear are slotted with the teeth of the smaller part of the counter gear. Give the combined assembly a few returns to make sure there is no binding and to check if sufficient lubrication has been applied to all gears. Take the left side of the transmission, shaft and large bevel gear are ready in place and swap the shaft of the differential gear into the receiver on its driveshaft. Use screws to bind the two sides together and lock the transmission into place. Now, we need to mount the electric motor. Take this small brass pinion and using an Allen wrench included in the kit, partially install the grub strew into the spot on the pinion gear. This is what will secure the pinion gear to the drive shaft and the motor. That pinion gear has a flat side that will line up with the flat side with the motor shaft. That we need to properly space the gear. Not so close as to make the gear Web against the body of the motor but not so far as to misalign the pinion and spur gear. A small piece of card there is included in the kit, use it to space opinion geared to the proper standoff. We now to need to attach the motor to the motor mount. This is the part that will hold the motor in the proper position against the transmission case. It is also the part that can be changed to allow the transmission to work with different size motors. The motor attaches to the mount and the amount is screwed into the transmission along with the end On the other side of the transmission assembly. Now we need to install the shock mounting points on each arm of the transmission assembly. Two small plastic mounts, each the mirror of the other, need to have a small brass ball connector installed with the included tool. Each can fit properly only on one side of the transmission so if it doesn't line up with the mounting post, just swap the sides. When we integrate the transmission with the chassis, these amounts will be used to connect the shock absorbers. Electric motors have a lot of torque and big wheels on a buggy have a tendency to make the vehicle rear up on its end. So I included a wheelie bar with a lunchbox. A small plastic wheel is held by a steel assembly which is then bolted onto the back of the transmission. The last step is to cinch the motors leads against the motor can, with the included tie wrap. This is to keep the wires from rubbing against the tires, especially under load. Though we won’t be installing the wheels until the integration of the transmission with the chassis it is worth taking a look at how the drive wheels will be attached to the transmission. Each driveshaft has a small hole just beyond the end of the transmission housing. A small metal pan is inserted into each hole and then the plastic wheel have is slotted over that pin. The panel keeps the hub locked onto the drive shaft and the club keeps the wheel locked onto itself. If you have built a transmission properly, turning the drive shaft on one side should create an opposite rotation on the other. If you get opposite rotation it means that both driveshafts are logged onto the differential gear and that the opinion on the motor has properly engaged spur gear. If the wheels spin in the same direction, or if the opposite wheels don’t spend and all than either the motor is improperly installed or the bevel gears are not properly seated. Congratulations, you have now fully assembled a functional transmission for your lunchbox.
Fr. Robert: That was actually a lot of fun.
Bryan: That looks like a lot of fun.
Fr. Robert: I love building those models because you can go to the toy store, you can buy something like this. But if you actually build it, you know how it works.
Bryan: You have intimate knowledge now.
Fr. Robert: Any gear head will know this feeling. It is one thing to own a bike, or own a car, but it is another thing to be able to take it apart. So many things these days are electronic and you can’t actually get in there. It is nice to have a kit that is so simple, it is just geared.
Bryan: Not only is it applied to this the car, but it is the same thing that you would see in real cars and stuff. It transfers over. And that is pretty cool.
Fr. Robert: For example if we take a look inside this, because in the next episode of Project lunchbox we're actually going to show you how to build up the steering and how to integrate the systems. But if we go ahead and take off the….
Bryan: Oh sorry. It’s on my snack. There is candy in here, hold on. I thought that was supposed to be… it’s a lunch box right? Okay, continue.
Fr. Robert: If you look inside, the transmission is one part of a very complicated system. We are going to show you next time how you actually connect the shocks, how you build out the steering, and how you create and adjust the linkage. And then all the electronics. There is a lot left in project lunchbox. This is just going to be the first of what we hope to be a long series of project builds.
Bryan: That is really cool.
Fr. Robert: By the way, I noticed that the lunchbox wasn’t at its normal places morning. It seems to have gotten scraped up overnight. Do you have any ideas?
Bryan: Yeah. So, as I found out, asphalt has a lot of traction. So when you try and do a power slide on a lunchbox? You do a power flip. And down the road in my neighborhood waking up all my neighbors at night. I learned that though. So now I’m not going to do it again. But you know what it does do? It pops curbs really well. It hops curbs, and then there is this bark patch out in front of my yard and it just kicks up all the bark. I’m going to do a slow-motion video.
Fr. Robert: I’m glad that I can build these models so that you can destroy them.
Bryan: You build them, I will break them.
Fr. Robert: It is a partnership.
Bryan: That’s how it works.
Fr. Robert: Now we know that we hit you with a lot of information this episode. Everything from next NFC tags to the transmission to how we actually build the transmission for project lunchbox. We don’t want to flood your knowledge hole, so we have given you a nice easy way to get our show notes. Where can they find them Bryan?
Bryan: They can find them at twit.tv/kh and that is where all of our past episodes also live. So if you think you might have missed something during the episode, definitely check out the show notes and there will be links to the apps that we used for NFC and some other stuff.
Fr. Robert: Information about the transmission and a step-by-step guide for the transmission. Now if you want to contact us you can always email us, actually if you want to contact us with the complaint and email us at because that gets sent to Jeff Needles. So please send some complaints to Jeff. We want Jeff to reply to all of those. But if you actually want to talk to us about what you would like to see in future episodes of Know How then join us on our Google plus group. Where can they find that?
Bryan: Well, I guess if you just google search the Know How community.
Fr. Robert: Jump in there. We've almost got 7000 members. The whole thing about this community is that we don’t really have to answer all that much anymore. We jump in every once in a while, but this group is filled with some really bright people. The people in our group are brilliant. Brilliant in their own way.
Bryan: It is just a fun place to look around because people post show ideas and post links to projects that they have done from the show, so it is a cool place to hang out.
Fr. Robert: And we are going to be taking some of your questions and integrating them into our show. So if you’ve got a question for the guys, go ahead and drop into our Google plus group. Now Google is not the only place you can find us.
Bryan: If you want to keep track of Padre falling asleep on the being bad or pictures of my corgi…
Fr. Robert: They can find me at twitter @PadreSJ. You’re at?
Bryan: I’m @cranky_hippo. That is my spirit animal!
Fr. Robert: What are we doing next time? Oh, next time we are going to be doing something with our upgrade project. Playing with the desktop and we are going to show you the best way to get some more juice.
Bryan: All the benchmarking you did. That was a lot of work for you.
Fr. Robert: Until next time, I’m father Robert Ballecer.
Bryan: And I’m Bryan Burnett.
Fr. Robert: Now that you know…
Bryan: Go do it!