쉐도잉 연습: Everything You Didn’t Know About Titanium Bikes - 영상으로 영어 말하기 배우기

레슨 만드는 중...
1
Titanium is a material that many people regard as the best.
2
But what actually is titanium?
3
How does it differ from other materials?
4
And why the hell would you make a bike from it?
5
To find out more, I'm going to go speak to an expert.
6
Titanium bikes do feel smoother.
7
The cost is always high.
8
What you're really paying for is energy.
9
Higher density than aluminum, a lower density than steel, higher stiffness than aluminum, lower stiffness than steel.
10
They last significantly longer, but it's not very strong.
11
Tom Sturdy is the man behind Sturdy Cycles
12
and has been making custom titanium bikes since 2014 using a
13
combination of titanium tubes as well as 3D printed sections and components.
14
Tom has got qualifications in aerospace engineering and sports biomechanics, which in my mind makes him the perfect person to help answer my questions.
15
Let's start right the beginning and find out what titanium actually is.
16
Titanium is an element, it's number 22 on the periodic table.
17
When you're talking about it being used in bikes, it's very rare that it would be used in its pure form.
18
You can use pure titanium metal for various things, but more often than not,
19
when it's used to make something like a bike or anything structural, it will be alloyed with some other elements.
20
Normally, aluminum and vanadium in different quantities.
21
To try to change the properties of it.
22
Why would you not use titanium just by itself?
23
Pure titanium, and it can be a bit confusing
24
because a lot of these alloys will have lots of different names and they're all very similar.
25
It can be confusing.
26
Pure titanium, titanium, it's got lots of useful characteristics of titanium,
27
so it doesn't corrode very, very, very slowly.
28
Essentially, it's corrosion resistant, but it's not very strong.
29
It'll bend quite easily and fatigue quite easily as well.
30
In terms of trying to make a bike from titanium, how are we going about doing it?
31
Is it in tube form?
32
Is it shaped and then welded together? like give us an explainer on that.
33
Yeah, so probably the main downside of titanium is
34
that it's difficult to work with and that kind of means sort of in all different ways of working with metal.
35
So it's very difficult to change its shape and
36
that typically is one of the challenges with it
37
but it will normally be used in tube form
38
so this is a drawn tube
39
and then yeah tubes will be cut to length butted up once again against one another
40
and welded together you can also change its shape in other ways
41
so yeah for making bikes sometimes it might be cast
42
or 3d printed and you can get different shapes from it that way.
43
You can also machine it.
44
Typically, the alloy that you would use for tubing would be different to the alloy
45
that you might use for a machined part.
46
This is like a machined part.
47
This is a chainring.
48
You've made this in -house.
49
This, explain to us how the hell we go from something that looks like this to something that looks like this.
50
Yes.
51
This is, that's a raw stock.
52
Well, it's come out of a big bar and they cut a little slice off it.
53
So this is a grade of titanium that is better suited to machining.
54
It's quite high strength, but it'd be very difficult to make tubes from this grade of titanium.
55
It can be done and some companies do it, but it comes with challenges with the material becoming brittle and that sort of thing.
56
This is well suited to machining.
57
In this case, we'll hold this in a CNC machine and gradually remove material until we're left with that.
58
I guess that's the same principle as what you have with other materials, that there's slightly different versions of it which are tweaked to suit the application.
59
In terms of looking at that titanium tube, how does something like that compare in its properties compared to like a steel tube or an aluminum tube?
60
What are the differences, especially if we looked at like for like profiles and shapes?
61
Yes.
62
Titanium is, it sits sort of, if we're thinking about the materials that you build bikes from,
63
titanium sits nicely in the middle in terms of its mechanical properties.
64
If you were to have the exact same tube and it were made out of aluminium.
65
The aluminium one would be lighter than this one.
66
But it'd be very rare that you'd have an aluminium tube with
67
that thickness because aluminium wouldn't be strong enough in that thickness.
68
So an aluminium tube would have to be thicker to be stronger?
69
Thicker, so the actual weight difference
70
when you are using it in a practical sense would be
71
less than the theoretical difference in terms of just the density but yeah
72
so titanium is is has a higher density than than aluminium
73
a lower density than steel higher stiffness than aluminium lower stiffness than steel strength will vary depending on the alloy
74
so it sits kind of nicely in the middle of the range of mechanical properties certainly for metals
75
that would be used to make bikes and
76
so you can use it to then design and make quite a broad range of types of bike.
77
You can make stiff bikes, flexible bikes, that sort of thing.
78
Quite fit in the balance of what you want to achieve.
79
In terms of looking at overall bikes built up ready to go, what are some of the reasons why somebody might want to
80
consider maybe a titanium bike over an aluminum one or a steel one or maybe even a carbon one?
81
There are lots of different considerations.
82
I think, generally speaking, certainly in the bike industry, different materials tend to have these different assumptions made about it.
83
So people will often assume that a carbon bike
84
rides in a particular way or performs in a particular way and the same is true of aluminium, titanium, steel.
85
So titanium is famously quite comfortable.
86
It's not really as simple as saying that because you've made a bike out of titanium it will be comfortable.
87
It'd be very easy to make an uncomfortable titanium bike.
88
Generally speaking, it will have these kind of sweet spots.
89
Because of the inherent properties of titanium, and then when you start to make it into a bike, it can tend to produce bikes that are quite comfortable.
90
There are other reasons.
91
It's essentially corrosion resistant, so it's not going to rust like a steel bike.
92
It's not going to easy to look after in the sense that because it doesn't corrode,
93
you don't need to paint it, so you don't have to worry about scratching paint, that type of thing.
94
You can ride it all year round, you don't have to worry about riding it.
95
What about in terms of robustness, actually?
96
Because when people talk about carbon fiber frames, one thing they say is, oh, you've got to be careful with it.
97
You don't want to bang it in the wrong ways or it's only strong in certain directions.
98
How would titanium compare in that sense?
99
So titanium is, I mean, it's inherently probably more robust in some ways than a composite just
100
because it's a metal and metals are homogeneous so they've kind of got equal strength in all directions.
101
So yeah, it's not like a carbon tube that if you crushed it in the wrong way you might damage it.
102
You could dent titanium if you hit it hard enough, but it's relatively difficult to do that.
103
It's quite tough, but every material has its limit.
104
Generally speaking, titanium has got a really good fatigue life and it is very strong for its weight.
105
Actually in absolute terms, it's very strong as well.
106
It is generally pretty robust, but there's no such thing as something that's - It's not indestructible, is it?
107
I'm sorry that people often say when you're talking about entertaining bikes, it's like, oh, there's that like entertaining buzz that you get.
108
Is that a thing and what on earth, how would you explain that to someone that wouldn't know what to expect?
109
It is to a certain extent, yes.
110
The material property is quite a, for want of a better word, it's quite a springy material.
111
It does tend to respond slightly differently to,
112
for example, the vibrations that you get from riding over a road, that road buzz.
113
That high -frequency stuff.
114
Yes, it will respond differently to other materials just because it has underlying properties.
115
I think as a general rule, titanium bikes do feel smoother to ride than other materials, but it's a little bit,
116
it'd be oversimplifying it to say that any titanium bike will because you can't.
117
It all comes down to the quality of the build, I guess.
118
Yes.
119
In terms of pricing, when you look at, I think, titanium bikes, I think it's fair to say typically you could say you
120
see far more custom titanium bikes than what you do in other materials,
121
but how would you rank a titanium bike and as a material in terms of price compared to other materials?
122
Yes.
123
It's pretty much the main downside of the material from a consumer point of view is
124
that the cost is always high
125
so titanium as a as an element is actually quite abundant there's a lot of it on earth
126
but it is very difficult to get it from its kind of raw or form into a useful
127
material and basically what you're really paying for is energy
128
and energy costs perpetually get higher right
129
and they're never really going to go down
130
so titanium will always be a relatively expensive metal from
131
that point of view and and it because it's difficult to work with
132
so for example machining the chainring that yeah yeah
133
if you were machining the exact same shape out of aluminium it would take a fraction of the time
134
because it's quite difficult to work with titanium and keep it in the right condition.
135
The problem really is that titanium bikes will always end up being more expensive
136
and that's why it tends to be used not at the lower end of the market.
137
Yes, it does tend to be at the high end custom type bike.
138
Yes, that's interesting.
139
Also, there is an additional way of starting to look at working with titanium, which is something that you are a big fan of.
140
Tell us more about something like this 3D printed lever.
141
3D printing is increasingly a common way of working with metals.
142
Aluminium, titanium, steel can all be printed.
143
One of the good things about it is that because titanium is very difficult to get into a particular shape.
144
3D printing is a great way that you can achieve that.
145
Of course, there are strengths and weaknesses of using additive manufacturing full stop,
146
but it's a great way that you can get the raw material into a shape that you want for some design application.
147
Or an intricate part like that.
148
Exactly.
149
We use it a lot to get a particular design intent from a performance point of view,
150
an aesthetic point of view.
151
We use it a lot in conjunction with, for example, machining.
152
Rather than starting out with a big block and removing a lot of material.
153
A lot of material.
154
When you compare this, it's crazy, isn't it?
155
Yeah, so additive manufacturing can be a really useful way of,
156
you know, you could print something that is nearly the shape you need and then machine the rest of it away.
157
And you could do that with casting as well.
158
There's different strength benefits one way or the other.
159
And of course, in a sense, for me, for my application where every bike we make is different and custom,
160
3D printing has an obvious advantage because you don't have to pay for tooling costs of a cast part.
161
That's a really interesting point there.
162
That's covered off loads of really important and useful information about titanium.
163
One key question I do want to ask you is,
164
do you think we're ever going to see titanium bikes and parts start to become more mainstream and more commonplace,
165
or do you think it's going to stay as that not quite elusive material, material, but a bit more of a niche material rather than something that's mainstream?
166
I think it will come down.
167
Cost is probably the main factor to consider there because it's so expensive as a raw material, it's difficult to work with or certainly slow to work with.
168
All of those things, the costs
169
that are added to the already high cost of the raw material are ones that are difficult to reduce.
170
I don't see an easy way that they would come down.
171
There is more automation that gets built into processes like additive manufacturing and machining as well.
172
But I think the main problem with it being used on a widespread level is,
173
yeah, it's just going to come down to the fact that cost and as we're seeing at the moment,
174
one of the big problems with bikes is that there aren't many at the low end of the market.
175
Yes, it certainly doesn't feel like a material that's going to lend itself to the budget end of the scale
176
or as an entry point into cycling.
177
I guess, like you said, if the cost of the raw material is already high, even in the future with whatever technology and process are developed,
178
if you're able to reduce the processing costs afterwards, you're already at a higher starting point, so it's always going to be difficult.
179
Yes, exactly.
180
That piece of titanium that makes that chain ring, just buying
181
that bit of material is already multiple times what it would cost me to buy an already finished aluminum chain ring.
182
I guess there is potentially the argument on the flip side of that, is that whilst the chain is more expensive in the initial outlay,
183
it could last an aluminum part over multiple times again.
184
Yes.
185
That's one of the reasons that, for example, that's one of the reasons that we make those chainrings is that they last significantly longer.
186
So over the kind of service life of the part, probably.
187
works out about the same if not a bit cheaper depending on how you want to do that.
188
That's actually a really good point.
189
Titanium is going to be a high price, it's unlikely to ever change, but one of the big advantages are its strength,
190
robustness, and the chance that it could outlive and outperform other different materials many times.
191
Yes, certainly.
192
Again, the bikes that we make here, they're all intended as lifetime bikes.
193
I'm expecting that those bikes will be in existence for as long as their owner wants to ride a bike.
194
That's certainly something that you wouldn't perhaps say of other materials that inherently just won't have such a long service life.
195
For me, that's one of the key draws and advantages for titanium.
196
I think that's what also draw other people to it as a choice material.
197
I think we've covered off pretty much everything that I could think about talking about.
198
Tom, thanks very much for your time.
199
It's all right.
200
No problem.
201
Hopefully, you found this video interesting and informative.
202
I certainly know I enjoyed speaking to Tom.
203
For me, a titanium bike is one which I wish to own, but unfortunately, it still seems to be a little bit out of my price brackets.
204
Remember, for all things bike and bike tech related, subscribe to GCN Tech because it also helps support what we do.
205
See you later.

이 영상, 영어 회화 연습에 딱인 이유

이 비디오는 "티타늄 자전거"에 관한 대화로, 일상적이지만 전문적인 용어도 섞여 있어 영상 영어 공부에 최적입니다. 자연스러운 발화 패턴과 질문-답변 구조가 돋보여, IELTS 스피킹처럼 실제 의사소통을 연습할 때 필요한 흐름을 익힐 수 있습니다. 특히 전문가와의 대화에서 자주 사용되는 "Why would you...?", "How are we going about..." 같은 표현이 많아, 회화의 유연성을 키우기에 좋습니다.

자연스러운 표현, 하나씩 분석해보기

  • "Titanium is a material that many people regard as the best." : "regard as"는 "~로 생각하다"는 뜻으로, "think of as"보다 더 공식적이지만 자연스럽게 사용됩니다. 이 표현을 사용하면 의견을 명확히 전달할 수 있어 IELTS 스피킹에서 유용합니다.
  • "What you're really paying for is energy." : "pay for" 뒤에 명사가 아닌 "energy"라는 추상적인 개념을 사용한 것이 특징입니다. 이렇게 구체적인 물건이 아닌 가치를 표현할 때는 이 구조를 활용하면 자연스러운 영어가 됩니다.
  • "It's very rare that it would be used in its pure form." : "It's rare that..."는 "~하는 경우가 드물다"는 뜻으로, 부정적인 상황뿐만 아니라 중립적인 설명에도 자주 사용됩니다. "pure form"은 "순수한 형태"로, 전문 용어를 배우면서 동시에 문장 구조도 익힐 수 있습니다.

쉐도잉 연습법, 이렇게 하세요!

영어 쉐도잉을 할 때는 다음 단계를 따라보세요. 1. 비디오를 5초씩 재생하고 멈춥니다. 2. 발화자의 톤과 억양, 속도를 따라서 반복합니다. 3. 녹음기로 자신의 목소리를 녹화한 뒤 원본과 비교합니다. 특히 "Why the hell would you..."처럼 감정이 담긴 표현은 억양을 잘 따라야 자연스러워집니다. 하루에 10분씩 이 연습을 하면, shadowing site에서도 배우는 것보다 실제 발화 능력이 빠르게 향상됩니다. 이 영상은 대화가 자연스러워 쉐도잉 초보자도 부담 없이 연습할 수 있어요.

쉐도잉이란? 영어 실력을 빠르게 키우는 과학적 방법

쉐도잉(Shadowing)은 원래 전문 통역사 훈련을 위해 개발된 언어 학습 기법으로, 다언어 학자인 Dr. Alexander Arguelles에 의해 대중화된 방법입니다. 핵심 원리는 간단하지만 매우 강력합니다: 원어민의 영어를 들으면서 1~2초의 짧은 지연으로 즉시 소리 내어 따라 말하는 것——마치 '그림자(shadow)'처럼 화자를 따라가는 것입니다. 문법 공부나 수동적인 청취와 달리, 쉐도잉은 뇌와 입 근육이 동시에 실시간으로 영어를 처리하고 재현하도록 훈련합니다. 연구에 따르면 이 방법은 발음 정확도, 억양, 리듬, 연음, 청취력, 말하기 유창성을 크게 향상시킵니다. IELTS 스피킹 준비와 자연스러운 영어 소통을 원하는 분들에게 특히 효과적입니다.