Speaker 1: Get in touch with technology with text Stuff from Stuff stat.
Speaker 1: Hey there, guys, and welcome to tech Stuff. This is
Speaker 1: Jonathan Strickland, and today we're gonna look back on a
Speaker 1: classic episode of tech Stuff. This is one that Lauren
Speaker 1: Vogel Baumb was on and it's all about transmissions. It's
Speaker 1: called what do Transmissions Do? And since Scott came in
Speaker 1: and we did an episode about electric bikes and we
Speaker 1: talked a bit about gear systems, I thought it would,
Speaker 1: you know, benefit us to revisit transmissions and understand how
Speaker 1: gears help us with our automobiles. So I hope you enjoyed.
Speaker 1: So what are we talking about with transmissions? What are transmissions?
Speaker 1: Why are they necessary? What's the deal? Well, first we
Speaker 1: have to understand that a vehicle, let's say a vehicle
Speaker 1: with an internal combustion engine, gets its power from the
Speaker 1: engine itself. Right, You're burning fuel within that engine and
Speaker 1: that engine is putting out power in the form of
Speaker 1: kinetic energy. Now, the trick is how do you make
Speaker 1: the kinetic energy that's generated by the engine make your
Speaker 1: vehicle move as opposed to just making noise or heat
Speaker 1: or explosions that would be an external combustion engine not
Speaker 1: a good thing. Not vehicles. Now, so, uh, what what's
Speaker 1: generally going on with a vehicle we're gonna take for
Speaker 1: this podcast. We're gonna specifically focus on a five speed
Speaker 1: manual transmission vehicle that has rear wheel drive. Now, there
Speaker 1: are a lot of different configurations you can have. The
Speaker 1: basic premise of the transmission is the same in all
Speaker 1: of these, but the way it's laid out is completely
Speaker 1: different depending upon the car's configuration. So this just for
Speaker 1: the purposes of this podcast, because we can't cover everything.
Speaker 1: It would be a four hour long pod least, and
Speaker 1: we we we'd have actually say I don't even know
Speaker 1: where I am anymore. We're gonna keep it fairly simple. So, really,
Speaker 1: the transmission is important for being able to take the
Speaker 1: power that an engine is generating and convert that into
Speaker 1: the kinetic energy that's necessary to get your vehicle moving.
Speaker 1: But before we get too far into that, let's kind
Speaker 1: of look back at why is a transmission even necessary,
Speaker 1: I mean, not beyond the fact of what it does.
Speaker 1: Why do we need something that like a variable transmission,
Speaker 1: Why not just something that converts the energy of an
Speaker 1: engine into the rotating force of wheels moving right. And
Speaker 1: this this has something to do with with the difference
Speaker 1: between um, the kind of energy that you want to use,
Speaker 1: when you're first starting a car, when you're accelerating it
Speaker 1: from a stop, and when you're speeding up later on
Speaker 1: down the line, right, and when you're when you're reaching
Speaker 1: your top speed as well. Yeah, As it turns out,
Speaker 1: an engine only has a very narrow range at which
Speaker 1: it's operating with its revolutions per minute, relatively narrow range. Uh.
Speaker 1: And if our vehicles worked within that same narrow range,
Speaker 1: we'd be fine, right, if everything was ideal, If somehow
Speaker 1: the range of the engine and the range of the
Speaker 1: motion of the wheels had a one to one ratio,
Speaker 1: whether it was directly uh, analogous, or you had to
Speaker 1: have some sort of gear shift in there too, uh
Speaker 1: to adjust it, we'd be all right. We wouldn't need
Speaker 1: a transmission, But we really need a wider range. And
Speaker 1: the two things that are really important when it comes
Speaker 1: to operating vehicles, uh, for for the purposes of this conversation,
Speaker 1: our speed and torque. Okay, So, so what's so? What's what?
Speaker 1: What is torque? Torque is is you can think of
Speaker 1: it as a twisting force. It's a rotational force. So
Speaker 1: whenever you have a wheel turning, uh, it's it's powered,
Speaker 1: it's that's that's that's torque there. Or if you're using
Speaker 1: a wrench, let's say that you need to loosen or
Speaker 1: tighten a bolt with a inch, you're using torque. It's
Speaker 1: this rotational force. The the end of the wrench is
Speaker 1: moving in a circle and the bolt is acting as
Speaker 1: sort of the axis of this of this pit or
Speaker 1: a pivot point for this motion. Uh. That's torque. And
Speaker 1: by increasing or decreasing torque, you can it's kind of
Speaker 1: what people talk about when they're talking about the grip
Speaker 1: on the road. Um, you can have a vehicle that
Speaker 1: has really high torque uh and really low speed. You
Speaker 1: can have a vehicle has really had speed really low torque.
Speaker 1: You can have lots of different combinations here. So for example,
Speaker 1: imagine a giant crane that you would use in a
Speaker 1: construction field. All right, so it's enormous and it's using wheels,
Speaker 1: not not treads or whatever. Uh, this vehicle is going
Speaker 1: to have an enormous amount of torque applied to the
Speaker 1: wheels in order to move this massive vehicle around. It
Speaker 1: may not be moving quickly, but the torque is really powerful,
Speaker 1: which means that it would require a lot of force
Speaker 1: to make sure that those wheels don't turn earn if
Speaker 1: the engine were operational and it was being put into drive.
Speaker 1: So if you were trying to hold those wheels still,
Speaker 1: you would have to use an enormous amount of force
Speaker 1: to counteract that torque. You could also have a toy,
Speaker 1: let's say that has a little spinning element to it
Speaker 1: that spins at an incredible rpm, but it doesn't do
Speaker 1: so very with very much torque at all. So if
Speaker 1: you just touched it, it would stop spinning, and it
Speaker 1: would just be the lightest touch to counteract that torque. Again,
Speaker 1: the torque is not very strong with that particular device.
Speaker 1: So when we're operating our vehicles, we actually need a
Speaker 1: fairly wide range of torque, which is not something that
Speaker 1: would be possible if we had to work within the
Speaker 1: narrow parameters of what an engine is able to put
Speaker 1: out with that range of RPMs. Right, if an engine
Speaker 1: only had one speed, and it would get really messy,
Speaker 1: really fast, right and exactly, and you know, the vehicle
Speaker 1: might operate fine in certain conditions, but if you change
Speaker 1: those conditions at all, then you'd be in trouble. And
Speaker 1: see that's the that's the issue, because we all know
Speaker 1: when you're out there driving, not everything is a perfectly
Speaker 1: flat highway. You know you're going to have inclines, you're
Speaker 1: gonna have changes in the in the environmental conditions that
Speaker 1: are going to require your vehicle to adjust as you
Speaker 1: are going through them. So that's why you need to
Speaker 1: have a transmission. You have to have something where you
Speaker 1: can shift to a different torque or speed in order
Speaker 1: to one maintain your grip on the road and continue
Speaker 1: moving at the appropriate speed and to operate within the
Speaker 1: engine's parameters. That's one of those reasons why, Like if
Speaker 1: you keep revving the engine and you're in first gear,
Speaker 1: you'll see that needle go all the way into the
Speaker 1: red and then if you keep that up, you burn
Speaker 1: out your engine. So by shifting, you are actually adjusting
Speaker 1: torque and speed and by doing that you can keep
Speaker 1: the needle in the the ideal operational So that's what
Speaker 1: the transmission is for. It's for keeping you in this
Speaker 1: in the sweet spot. And there are of course manual transmissions,
Speaker 1: automatic transmissions, there are variants of those, UM and UH
Speaker 1: and while we're really focusing on manual transmissions, if we
Speaker 1: were to talk about automatic I think I would have
Speaker 1: to call someone else in because yeah, we would need
Speaker 1: Scotten here, because it's a little bit beyond what we
Speaker 1: are certainly our personal technical level with the automotive industry.
Speaker 1: Not to mention the fact that I don't know how
Speaker 1: I would explain it in words without the benefit of pictures.
Speaker 1: It's already an interpretive dance, and that works less well
Speaker 1: on podcasts. But you might you might hear us like
Speaker 1: with by the microphone, but it kind of loses something
Speaker 1: in the translation. All right. But so, originally automobiles only
Speaker 1: had two forward gears in one reverse. So, but they're
Speaker 1: the engine capacity was much less, so so those narrow
Speaker 1: ranges were kind of okay within two gears. Um Around
Speaker 1: the early nineteen forties late nineteen thirties, um Ford and
Speaker 1: Chrysler started introducing semi automatic gears that would let you um,
Speaker 1: you still had to use a clutch, but you could,
Speaker 1: but you could switch between them between the higher gear
Speaker 1: semi automatically. In the nineteen fifties, the first full automatics
Speaker 1: were debuted and uh and then after that all of
Speaker 1: the advances have been in the in the number of speeds,
Speaker 1: the number of gears that are involved in these transmissions.
Speaker 1: So we went from we went from two up to
Speaker 1: UH four speed manuals, and then six speed manuals started
Speaker 1: hitting the market in the late nineteen eighties, right, So
Speaker 1: uh and you might wonder why do you have why
Speaker 1: why do you add more of those divisions, more of
Speaker 1: those speeds. It doesn't necessarily mean that the vehicle is
Speaker 1: going to go faster than earlier vehicles. It does mean
Speaker 1: that the transitions between between the different speeds or the
Speaker 1: different gears becomes a little more smooth because you've you've
Speaker 1: refined them, You've you've made it a little more precise. Right.
Speaker 1: It lets the engines work less hard at the specific
Speaker 1: task that you were asking them to do at the time.
Speaker 1: Along these lines, just just about a couple of days
Speaker 1: ago as of the recording of this podcast, in mid
Speaker 1: April teen GM and four General Motors of course and
Speaker 1: Ford announced that they're going to to work together to
Speaker 1: develop nine and ten speed transmissions. I'm assuming those are
Speaker 1: automatic transmissions at this point, because that sounds like a
Speaker 1: very large gearshift that will, you know, for for consumer vehicles,
Speaker 1: and that will uh, you know, save gas mileage. It
Speaker 1: could it could raise gas mileage by five to ten percent,
Speaker 1: which is you know, not no insignificant, right, and then
Speaker 1: you're talking about decreased environmental impact. There are a lot
Speaker 1: of other benefits that roll out through these, uh some
Speaker 1: people might call them small evolutionary changes, but they can
Speaker 1: make a big difference down the road. Did not mean
Speaker 1: to do a pun there one goes out the crystal edge,
Speaker 1: accidental puns. We don't we don't need any of those.
Speaker 1: Doesn't mean to do it, all right, So so you
Speaker 1: might be thinking, all right, how does this whole torque
Speaker 1: shifting thing work? And we're going to get into the
Speaker 1: actual mechanics literally of it in a little bit, but
Speaker 1: in general, think of two gears. All right. If you
Speaker 1: have two gears are the same size, and they are
Speaker 1: they have teeth that interlock. When you turn one gear,
Speaker 1: the other gear is going to turn at that same rate.
Speaker 1: It's going to be the same number of revolutions per
Speaker 1: minute because they are the same size, same same number
Speaker 1: of teeth, all that kind of stuff. Now, let's say
Speaker 1: that you have a large gear and a smaller gear
Speaker 1: and they are interlocking and you're turning the large gear,
Speaker 1: that smaller gear is going to do more revolutions per
Speaker 1: minute than the large gear. You know, when you go
Speaker 1: from the starting point all the way back around to
Speaker 1: the starting point in the large gear, the small one
Speaker 1: may have turned three or four times, depending upon the
Speaker 1: ratio between the two. Right, same thing. If you have
Speaker 1: a small gear in a large gear and you're turning
Speaker 1: the small gear, you're gonna have to turn that small
Speaker 1: gear several times, you know, large gear to right exactly.
Speaker 1: And and these these differences in speed also result in
Speaker 1: a difference in torque. So that's what's going to become
Speaker 1: important when we start talking about the actual process of
Speaker 1: shifting and what's going on with the transmission. For us
Speaker 1: to understand that, we're really gonna have to take a
Speaker 1: look at the entire drive train of a vehicle, which
Speaker 1: is both exciting and intimidating to me. I think, so,
Speaker 1: I think it's really cool. It's this is this is
Speaker 1: really entertaining physics to me, because I have I have
Speaker 1: I mean, Jonathan doesn't really drive. No, Jonathan doesn't drive.
Speaker 1: Don't don't even bother putting the word really in there.
Speaker 1: Jonathan does not drive. We wait, we fortunately have a
Speaker 1: limitedly robust public transport system. I can get land, I
Speaker 1: can get generally to where I need to go. Um uh,
Speaker 1: and I do drive. But I'm a very I'm not
Speaker 1: I'm not particularly a car person. So but this is so,
Speaker 1: this is going to be an exciting Yes. I will
Speaker 1: ask Lauren about her experiences with manual transmissions later on
Speaker 1: in the podcast, So stay tuned to find out about
Speaker 1: Lauren's own personal adventures with this technology. All right, let's
Speaker 1: get back to how transmissions actually work. So to do this,
Speaker 1: we have to look at the entire si stum that
Speaker 1: makes the car go. All right, and you're you're only
Speaker 1: interacting in this five speed manual transmission that we were
Speaker 1: talking about with with two bits of the clutch and
Speaker 1: the gearshift. Yeah yeah, but but there's a lot going
Speaker 1: on under this, Yes, a whole lot. And so first
Speaker 1: we need to just understand what these what these different
Speaker 1: parts are. So you've got your car's engine. This is
Speaker 1: the thing that makes it go. Ultimately, as you are
Speaker 1: depressing the gas pedal, you are putting in more fuel
Speaker 1: to the engine, which is then generating more uh power.
Speaker 1: It creates more kinnetic energy in the form of the
Speaker 1: pistons moving up and down. Those pistons are connected to
Speaker 1: a crank shaft, which converts the reciprocating motion that's the
Speaker 1: up and down motion of the pistons, into rotary motion,
Speaker 1: meaning it's turning into turning in a circular pattern. Now,
Speaker 1: so the crank shaft goes from the up down motion
Speaker 1: to the rotation motion, which is the very basis of
Speaker 1: everything else that's going to have. And now the crankshaft
Speaker 1: connects to a flywheel. Now, the fly wheel transmits this
Speaker 1: rotary rotary motion to a clutch plate, and the clutch
Speaker 1: plate is but eventually connects to that clutch pedal. Yeah. Yeah.
Speaker 1: In fact, there's a pressure plate that is pressed up
Speaker 1: against the clutch plate, right, So the pressure plate, when
Speaker 1: it's in contact with the clutch plate, allows this rotary
Speaker 1: motion to transmit through the rest of the of the
Speaker 1: vehicle's drivetrain. So when these two things are in contact
Speaker 1: with one another, uh, as long as the engine is going,
Speaker 1: then there is some sort of rotation being transmitted at
Speaker 1: that point, assuming you're not in just a neutral So
Speaker 1: what happens when you hit the clutch, Well, when you
Speaker 1: hit the clutch, the pressure plate rises up off of
Speaker 1: lifts off the clutch plate. Once the pressure plates separates
Speaker 1: from the clutch plate, all power is cut off to
Speaker 1: the best of the transmission, the rest of the transmission exactly.
Speaker 1: So so while the engine is still going, uh, it
Speaker 1: is not providing rotary force to the transmission and wheels,
Speaker 1: which is what allows you to shift gears exactly without
Speaker 1: making things explode. All right, this is why you why
Speaker 1: if you're driving a manual, you know, driving stick, you
Speaker 1: have to hit the clutch first, because that ends up
Speaker 1: pulling that pressure plate off so that you are able
Speaker 1: to shift gears without making the horrible grinding noise and
Speaker 1: destroying your big brother's vehicle. Uh. I say big brother,
Speaker 1: because I know a guy who did do that. Yeah,
Speaker 1: I was not there, thankfully. So assuming that the clutch
Speaker 1: plate and pressure plate are in contact with one another,
Speaker 1: you you have not just hit the clutch. Um it
Speaker 1: is then providing that rotary motion to the gearbox shaft. Now,
Speaker 1: the gearbox consists of several parts itself. You've got the
Speaker 1: main well, You've got a lay shaft which is connect
Speaker 1: to that gearbox shaft. You've got a main shaft aft
Speaker 1: and you've got several gears attached to both. You also
Speaker 1: have something that's either called a dog clutch or a collar,
Speaker 1: depending upon who you're talking to, and that is what
Speaker 1: is connected to a selector mechanism, which in the case
Speaker 1: of most vehicles, we think of as the stick shift,
Speaker 1: the manual shift. So, uh, the lay shaft is has
Speaker 1: got gears that are actually part of that shaft. They're
Speaker 1: they're they're splind spleened. Spleened is probably not the correct pronunciation,
Speaker 1: And I'm going to assume it's splend directly to the shaft.
Speaker 1: In other words, it's got a direct attachment. So as
Speaker 1: the chaft turns, so do the gears. Those gears have
Speaker 1: teeth along the edges and they interlocke with gears that
Speaker 1: are on the main shaft. But here's the big difference
Speaker 1: between the gears on the lay shaft and the ones
Speaker 1: on the main shaft. The gears on the main shaft
Speaker 1: are mounted on ball bearings, so they can spend freely
Speaker 1: around the axis of the main shaft without actually turning
Speaker 1: the main shift right, They're just kind of ghosting along
Speaker 1: over it into well, they become connected to the shaft
Speaker 1: through another piece of technology. Yeah, that would be the
Speaker 1: collar or dog clutch. Now, this is attached directly to
Speaker 1: the main shaft. It can slide to the left or
Speaker 1: right along the main shaft, but if it turns, the
Speaker 1: main shaft turns. So by interlocking the color with the
Speaker 1: side of one of these main shaft gears, both both
Speaker 1: the collar and the main shaft gears have teeth have
Speaker 1: teeth along the sides of them so that they can interlock. Yeah, exactly, So,
Speaker 1: so imagine that I think of it this way. You've
Speaker 1: got a gear that's got teeth along the outer edge
Speaker 1: like a like you would see in a typical gear,
Speaker 1: but you also have if you're looking at it from
Speaker 1: from one of the sides, so you're not looking at
Speaker 1: it headlong. You've turned it sideways, so you're looking at
Speaker 1: it like you know, like a plate you're holding it up,
Speaker 1: it would have teeth and holes along the surface that
Speaker 1: you're actually looking at, and those interlock with the collar
Speaker 1: or dog clutch, right, they kind of sandwich together. Right,
Speaker 1: So what happens is the lay shaft gears turn that
Speaker 1: makes the main shaft gears turn, and if the collar
Speaker 1: is is engaged in that particular mainshaft gear. Then the
Speaker 1: main shaft turns. Uh. I know, it sounds really confusing.
Speaker 1: It's a little difficult to get across without having visual effects.
Speaker 1: We will, by the way link on Facebook two pictures
Speaker 1: and videos of this, so it makes it easier to
Speaker 1: to to visualize and understand. But once you've got that
Speaker 1: main shaft turning, that's what then provides rotary motion to
Speaker 1: the differential. The differential's job is to to turn that
Speaker 1: rotary motion ninety degrees because at this point, before you
Speaker 1: hit the differential, that rotation is perpendicular to the wheels,
Speaker 1: which would not work. You wouldn't get the wheels to
Speaker 1: turn that way. Not very useful. Now, yeah, you have
Speaker 1: to turn that rotor rotation, that motion to be parallel
Speaker 1: with the wheels in order to get them to turn.
Speaker 1: So you can go forward or backward, depending upon which
Speaker 1: gear is is engaged. So the differential is a set
Speaker 1: of gears that transmits this dy degrees, so you can
Speaker 1: do that again. This is your basic five speed manual
Speaker 1: transmission with rear wheel drive. So that's the basic layout.
Speaker 1: But what's going on with the transmission alright? So remember
Speaker 1: I said that you had the lay shaft and the
Speaker 1: main shaft, both of which have gears on them. So
Speaker 1: imagine that the lay shaft gears are set up so
Speaker 1: it's gears that are increasing in size as you go
Speaker 1: from gear one to gear five, and then you have
Speaker 1: the your Your final gear on that shaft is for reverse.
Speaker 1: It's about the same size as the one that's going
Speaker 1: to be on the main shaft. Along the main shaft,
Speaker 1: of course, the gears are going to be in reverse
Speaker 1: order of size. So for the small lay shaft gear,
Speaker 1: you have a large main shaft gear, The next main
Speaker 1: shaft gear is a little smaller, the next one a
Speaker 1: little smaller, and a little smaller, so by the time
Speaker 1: you get to fifth gear, you've got a large lay
Speaker 1: shaft gear and a small main shaft gear. This is
Speaker 1: all because of that that relationship between speed and torque
Speaker 1: I was talking about. So if you've got a small
Speaker 1: lay shaft gear turning a large mainshaft gear, that means
Speaker 1: that the larger mainscheft gear has more torque but less speed.
Speaker 1: So that's important when you are accelerating from a stop
Speaker 1: so your car has not started moving, you want to
Speaker 1: engage that small gear on the lay shaft to turn
Speaker 1: the large gear on the main shaft so that you
Speaker 1: will start to accelerate from a stopped position. Now, once
Speaker 1: you start speeding up, you are eventually going to require
Speaker 1: the engine to do more power, more work than what
Speaker 1: it is comfortable doing. That's when you need to shift
Speaker 1: to second gear, which will be a decrease in torque
Speaker 1: but an increase in speed. And it's because that gear
Speaker 1: ratio has changed. The lay cheft gear is a little
Speaker 1: larger for gear too, and the main shift gears a
Speaker 1: little smaller for gear too. That's where you get that
Speaker 1: change in torque and speed. And this is true for
Speaker 1: for each speed step up, for each gear step up. Yeah, exactly.
Speaker 1: So once you get up to gear five, if that's
Speaker 1: when you're going really really fast, but I don't know, yeah,
Speaker 1: about as fast as the engine can hand without you know,
Speaker 1: having you drive off a cliff dukes of Hazzard style,
Speaker 1: in which case gravity takes control in your acceleration is
Speaker 1: completely dependent upon that. But that's the general progression. So
Speaker 1: if you're looking at how does the power flow, I'll
Speaker 1: walk you through it one more time. So power goes
Speaker 1: like this engine to pistons. Pistons to crankshaft, crank shaft
Speaker 1: to flywheel, flywheel to gear shaft, gear cheft to lay shaft,
Speaker 1: lay cheft to lay shaft gears, lay shaft gears to
Speaker 1: main shaft gears, mainshift gears to the dog clutch or
Speaker 1: color color to main shaft, main shaft to differential, differential
Speaker 1: to wheels and the wheels on the bus go round
Speaker 1: and round the red things connected to my wristwatch. Yeah,
Speaker 1: there you go. And so, uh, when when you are
Speaker 1: shifting gears, what what's actually happening is again you hit
Speaker 1: the clutch. It then separates the power of the engine
Speaker 1: from the from the gearbox down the line. So that
Speaker 1: allows you to move the collar or dog clutch from
Speaker 1: one of those gears to another. And if if you
Speaker 1: want to visualize it, imagine that you've got a horizontal
Speaker 1: pole and you've got gears going from the largest to
Speaker 1: the smallest and in reverse, which is kind of a
Speaker 1: medium sized gear. I'll get the reverse in a minute,
Speaker 1: because that one's kind of interesting, like how do you
Speaker 1: make it go backwards? You might say, well, um, you've
Speaker 1: got this this range of gears between each set of two,
Speaker 1: you've got one of those dog clutches or collars that's
Speaker 1: directly attached to the main shaft, all right, so that
Speaker 1: that collar can move to the left or right along
Speaker 1: this horizontal pole and engage either of the two gears
Speaker 1: that are on either side of it. And there, yeah,
Speaker 1: there's set of these in a in a manual five speed,
Speaker 1: there's going to be three of these collars, right because
Speaker 1: between gears one and two, gears three and four and
Speaker 1: gears five and verse, or you know, whatever configuration there are,
Speaker 1: that's that's where the collars would be and they would
Speaker 1: be able to engage either of the two whichever one
Speaker 1: on either side. So if you're in gear number one
Speaker 1: and you're speeding up to gear number two, you hit
Speaker 1: the clutch, the pressure plate comes off, the clutch plate.
Speaker 1: Power is cut off to the from the engine to
Speaker 1: the transmission exactly. Uh. And then as you shift the
Speaker 1: gear shift from one to two, the dog collar disengages
Speaker 1: from one and moves into the gear too, locks in place.
Speaker 1: By that time, you've you've let off of the clutch
Speaker 1: and the power gets re engaged and it just starts
Speaker 1: turning or it allows that main gear, that main shift
Speaker 1: gear to turn that dog collar at that point it
Speaker 1: goes torques decreased speed is increased, yes, um and uh.
Speaker 1: And that is the grinding that you hear. Actually, if
Speaker 1: you miss shift, it's going to be the teeth on
Speaker 1: the side of the collar against the teeth on the
Speaker 1: side of the main shaft gear that it's trying and failing.
Speaker 1: It has nothing to do with the lay shaft. That's
Speaker 1: always going to the lay shaft and main and main
Speaker 1: shaft gears are always going to be turning at the
Speaker 1: same general speed depending upon how much power you're giving
Speaker 1: the engine. They are not. It has nothing to do
Speaker 1: with the lay shaft at all. It's just that main
Speaker 1: shaft gear although in originally in manual transmissions they were
Speaker 1: called sliding gear transmissions, and the main shaft gears were
Speaker 1: in fact s blind to the main shaft so so
Speaker 1: they weren't on those ball bearings, they weren't floating along it,
Speaker 1: so which which meant that the grinding noise that you
Speaker 1: would hear in those originals was in fact the teeth
Speaker 1: of the main shaft gears failing to line up and
Speaker 1: grinding against the lay shaft gears. I would imagine you
Speaker 1: would only have one lay shaft gear and you would
Speaker 1: have variable main shaft gear sizes, and that's what would
Speaker 1: you know? It would just shift along those That's how
Speaker 1: I would imagine that would work. Of course I don't
Speaker 1: know because I didn't look into that. But that's that's
Speaker 1: my first reaction, based upon how how the typical five
Speaker 1: speed manual transmission card works. I didn't look that deeply
Speaker 1: into it, so I can I can neither confirm nor deny.
Speaker 1: I'm sure one of my listeners will take me to
Speaker 1: task and explain how I got that completely wrong. That
Speaker 1: was just me guessing from based upon my understanding of
Speaker 1: the other the other method. So so reverse, how does
Speaker 1: reverse work? Reverse is interesting because you actually have three gears,
Speaker 1: not just the two, Not just the lay shaft gear
Speaker 1: and the main shaft gear. There's a tiny little gear
Speaker 1: in between them called the idler gear. Now, because you
Speaker 1: have a third gear there that's in between two gears,
Speaker 1: you actually reverse the rotational direction for the main shaft gear.
Speaker 1: So while all the other let's let's use you know,
Speaker 1: clockwise and counterclockwise, while all the other main shaft gears
Speaker 1: maybe turning in a clockwise motion based upon your perspective,
Speaker 1: the reverse one will be moving in a counterclockwise motion
Speaker 1: or winter Shans for my Shakespearean friends, because that other,
Speaker 1: that tiny little gear is all that needs to happen
Speaker 1: to h to reverse that motion. This is easy to
Speaker 1: see if you ever have gears just to play with.
Speaker 1: So if you interlock two gears and you and you
Speaker 1: turn them, you'll see that based upon the rotation of one,
Speaker 1: the rotation together is always going to be the same.
Speaker 1: When you put a another gear between them and you
Speaker 1: turn the first one the third one, the third gear
Speaker 1: that used to be the second gear is now turning
Speaker 1: in the opposite direction as it did before because you've
Speaker 1: got that that intermediary gear, the idler gear. So that's
Speaker 1: what happens when you switch into reverse. It uh it
Speaker 1: the collar engages with the main shaft gear that is
Speaker 1: being turned by this idler gear that in turn is
Speaker 1: being turned by the lay shaft gear. And to everything turn, turn, turn,
Speaker 1: there is this ask your parents, all right? So uh,
Speaker 1: that's that's the basis for manual transmission. Automatic transmission is
Speaker 1: a little a lot more complicated because we would be
Speaker 1: talking about planetary gears, which include and I'm not making
Speaker 1: this up for people who are unfamiliar with It includes
Speaker 1: a planet gear, of sun gear and a ring gear,
Speaker 1: but it's all incorporated into one component, and it it
Speaker 1: might as well be magic. Uh, it is beyond my ken.
Speaker 1: I know that Scott understands it backwards and forwards, and
Speaker 1: if he were in this room right now, he would
Speaker 1: just be quietly chuckling to himself, not in the mean way,
Speaker 1: just in his money. Yeah, it's so cute that you're
Speaker 1: trying kind of way. But now comes the important part
Speaker 1: of our podcast, Lauren, I want to know about your
Speaker 1: experiences driving a stick shift car because I have none. Yeah. Yeah,
Speaker 1: the well, I've I've never um done a whole lot
Speaker 1: of time driving stick shift cars. This is a very
Speaker 1: brief series of lessons that I received from from from
Speaker 1: one of the first people that I dated, Bob, who
Speaker 1: was a big car enthusiast and was really keen on
Speaker 1: teaching me how to drive a stick And so the
Speaker 1: first time that I got into this, yeah, I had driven,
Speaker 1: I'd driven automatics before, so I was I was passingly
Speaker 1: familiar anyway with how cars worked. But but I got
Speaker 1: in and I sat down and he was like, all right,
Speaker 1: well you're a neutral, so um, so you're gonna want
Speaker 1: to disengage the clutch, and I was like, clutch where
Speaker 1: this was where Bob learns that perhaps there's a preliminary
Speaker 1: lesson that needs to be taught before the practical. Yeah,
Speaker 1: it was, it was, it was. It was a slow start. Well,
Speaker 1: I have to admit, like I I used to a
Speaker 1: friend of mine every now and then we get a
Speaker 1: chance to drive his mother's car. And his mother's car
Speaker 1: was a manual transmission, and I used to take both
Speaker 1: delight and genuine terror, uh, the experience of screaming whenever
Speaker 1: he would start to pull out of our high school
Speaker 1: parking lot and halfway through the turn the car starts
Speaker 1: to stall out because he's not Yeah, he's not handling
Speaker 1: the car proper, right, Right, there's when when when when
Speaker 1: you press the clutch, there's this you um, you can
Speaker 1: feel when it engages and disengages and um, and you
Speaker 1: have to pay very close attention. I've noticed anyway in
Speaker 1: the cars that I've driven to to where that is.
Speaker 1: And that's when you can use the gear shift and
Speaker 1: if you miss it, then you either stall out or
Speaker 1: you get that terrible grinding noise and you're lucky, right, Yeah,
Speaker 1: And that is that is a thing that I'm really
Speaker 1: I'm really awful at. I could, I could always I
Speaker 1: was fine driving out highways when I could kind of
Speaker 1: just go up to five and hang out there for
Speaker 1: a long time. But but once we got back into
Speaker 1: into town, I would be like, you know what, I'm
Speaker 1: going to pull over into the first gas station, set
Speaker 1: it into neutral and just like leap screaming from the
Speaker 1: car and allow somebody with more experience to handle. Alright,
Speaker 1: note to self, Alright, so uh yeah, I mean that.
Speaker 1: And of course people there are people who genuinely love
Speaker 1: driving driving manual transmission cars because they have that sense
Speaker 1: of they've got even more control over the vehicles and
Speaker 1: and you really can feel I mean, I I understand
Speaker 1: it's fun. I mean it's it's it's fun to to
Speaker 1: get to to get to move stuff around and you
Speaker 1: feel like you're a crazy action here and if you
Speaker 1: feel the road better and you feel like you do
Speaker 1: have more control over what the engine is doing. But
Speaker 1: but in stop and go traffic, like for example, every
Speaker 1: day in Atlanta, it's not something that I would particularly relish. Right, Yeah,
Speaker 1: if you're if you're driving a nice scenic route where
Speaker 1: there's not all that stuff and going might be a
Speaker 1: huge blast, but in in you know, your day to
Speaker 1: day traffic, it might be a little bit more of
Speaker 1: a nuisance over time. I hope you enjoyed that look
Speaker 1: back at tech Stuff and remember, if you want to
Speaker 1: get in touch with us, you can send me an email.
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