Slot car racing for the rest of us

I’ve always wondered about the slot car craze of the 70′. I heard so much about it. But I never did understand its lure. Unlike RC flying, slot car racing provides a racer with only one degree of control. You go fast, or even faster, until your slot car derails, and flies off a track.

Classic slot car racing

After I bought a starter kit recently, I now appreciate why classic slot car racing can be a hobby, and not just a toy. I get that at the enthusiast end of the spectrum, die-hard collectors and racers build elaborate custom tracks and cars. I know that at the toy end of the spectrum, cheap slot car kits are available for $30 to keep toddlers entertained.

But the majority of potential customers for slot cars do not belong to either end of this spectrum. There is a reason why slot cars soon faded from the popular stage. Most casual users find the experience thrilling only for a brief moment. After an initial adrenaline rush, the game soon become repetitive and one-dimensional for casual users.

Table of Contents

What’s missing in slot cars for the rest of us

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How to skate Mabrouk: 4 slalom components

This is part 2 of a series on Mabrouk. In this part I describe in excruciating details the four slalom components of Mabrouk previously summarized in What is Mabrouk: a slalom variant of Grapevine. I learned to skate a sustained Mabrouk by first practicing the four slalom components, and by connecting them with rudimentary transitions. I later refined these transitions to make the entire Mabrouk sequence flow, but that is for part 3 and beyond of this series.

Following diagram and filmstrip recap key takeaways from part 1. Remember to read them from right to left, as indicated by the yellow arrow showing the direction of body movement. Labels s1, s2, s3 and s4 denote the four slalom components of Mabrouk. Transitions are annotated by balance moments b1, b2, b3 and b4. Vertical blue and pink bands show when left and right skates glide alone as the primary bearer of body weight. Thus, the blue left skate can be seen bearing weight and gliding around balance moments b1, and later around balance moment b3. The red right skate can be seen bearing weight and gliding around b2, and later around b4.

Summary diagram showing key ingredients of Mabrouk, a slalom variant of Grapevine
Key frames of Mabrouk, for comparison to the summary diagram above

Similarly, the filmstrip above illustrates a full Mabrouk sequence, incorporating both slalom components s1, s2, s3 and s4, and balance moments b1, b2, b3 and b4. Remember to read them from right to left, as indicated by the yellow arrow showing the direction of body movement. At every component and moment, the projected center of gravity is indicated by a yellow circle on the ground. Slalom components are labeled in white – they are symmetric distribution points where both skates shoulder body weight equally. Balance moments are transition steps where one skate shoulders all body weight, colored blue when the left skate carries body weight and glides, and red when the right skate does so.

TLDR: for those of you who just want simple instructions on learning Mabrouk, search for the label TLDR on this page. You may ignore deep introspections and tedious expositions on Mabrouk. Those are really for academics, and for learners with too much time in their hands.

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What is Mabrouk: a slalom variant of Grapevine

Mabrouk is a slalom variant of a figure skating move called Grapevine. The Grapevine skating pattern is described and diagramed as early as 1880 by Vandervell and Cox in “A System of Figure-skating”. The slalom version is presumably named after Swiss slalomer Eddy Mabrouk. Both Mabrouk and Grapevine employ the same exact 4 components, namely forward/backward criss-cross, and forward/reverse eagle.

While Mabrouk emphasizes four curved slalom footwork around equally spaced cones. Grapevine strives to have the skater move in a streamline without giving explicit thoughts to slalom components. This difference can be seen in patterns they trace on the ground as presented below.

Pattern traced by Mabrouk (top) compared to Grapevine (bottom)

While the two diagrams look very similar, in actuality these two moves are skated with distinct attitudes and goals. To skate Mabrouk, one has to keep the cones in view and constantly adjust skating patterns accordingly. On the other hand, Grapevine is skated more freely, with the eye trained in the general direction of body movement, despite the 180° turning of the hip from side to side. A skater primarily moves in a streamline in Grapevine. Thus the gliding skate will trace a slightly flattened slalom curve as there are no cones to avoid.

Daniel skating Mabrouk
Naomi skating Grapevine

Like Grapevine, Mabrouk is also skated exclusively on outside edges. This when done to perfection appears to an onlooker as if a skater had Jackson’s moonwalk power, and could effortlessly propel herself indefinitely around cones, while turning forward and backward, without ever lifting any skates from the ground.

I have previously written much about Grapevine already. I started by trying to learn the ice skate version Grapevine, even before I could skate much. That journey was documented in Learn to Skate the Two-foot Grapevine Analytically. But I never quite managed to sustain the move indefinitely on ice, even though I understood intellectually how it would be done. I subsequently tried to skate Grapevine on inline skates. This turned out to be even more difficult, due to much stronger friction between wheels and pavement, compounded by my unfinished Grapevine training. However, instructions from Naomi Grigg on toe pivots and heel pivots proved to be enlightening, as I recounted in Learn the Two-foot Grapevine on Inline Skates. While I still couldn’t sustain Grapevine indefinitely on pavement, I was finally able to do so on ice by applying these pivots.

It wasn’t until I followed a great YouTube video on Mabrouk from Daniel of SkaMiDan fame that I truly managed to string all four component moves of Grapevine into a continuous sequence. In other words, the Mabrouk way of looking at the same four components was eye-opening. Breaking the sequence into four distinct and common slalom components allowed me to learn to cleanly transition from one component into the next. It taught me how to inject energy into the sequence at every one of these four components. I finally had a mental model for how to articulate these transitions, and to string the four components into a single sustained flow.

This article is part 1 of a series of articles that together document my learning journey for anyone in the same position. But first, go watch Daniel’s video, and subscribe to his channel. Daniel has gracefully allowed me to use his excellent video as a source material for illustration in this article. Thanks, Daniel!

Daniel’s video on Mabrouk
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Asian-fit helmets are a lot of hot air

Asian Americans who bike or skate know that helmets sold in America are generally not shaped properly for their heads. This is a phenomenon alien to most non-Asian people. Lately some brands have come out with so-called “Asian Fit” models. After an extensive research, I think these are just hot air, except for possibly a few exceptions.

Three types of helmets: skating, biking & hockey

Helmets sold in the US are molded to the average shape of European heads, roughly with a 1.3 ratio expressed in length over width of the head. In visual terms, you can picture a human head measuring 9″ from forehead to the back, and 7″ from ear to ear, shown below left. It’s got the shape of an oval, if you look at the head from top down. But Asians have a rounder head shape, with an average ratio of 1.16 instead. Picture a human head measuring 8 ¾” from forehead to the back, and 7 ½” from ear to ear, shown below right.

Most helmets sold in the US are sized by the circumference of a typical European head. A typical LARGE-size helmet targets an oval-shaped head with a circumference of 23″, or slightly larger. This LARGE helmet fits snug on a European head measuring 9″ long and 7″ wide, as shown below left. Often people order helmets online, based on advertised sizing charts. If an Asian American makes the mistake of buying a LARGE helmet thus, sight unseen, they will be disappointed. The helmet will not fit at all, as the sides of the helmet will be too narrow for an Asian head, as shown below right.

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Wednesday Night Skate NYC

Wednesday Night Skate NYC is also known as WNS NYC. It’s one of several well-established groups in the city. Some say it’s the biggest group of them all. WNS is run by volunteers since the late 1990s. Every Wednesday from April to October, weather permitting, organizers show up wearing yellow-green vests at the south-side steps of Union Square around 7:45pm. By then a sizable crowd of skaters have already gathered at the steps. At 8pm an organizer gives a brief safety speech and introduces the route planner of the week, as even more skaters materialize all of a sudden at the steps. One organizer is appointed the leader of the day, and another the sweeper. Folks are told not to skate ahead of the leader. The sweeper makes sure to leave no skater behind. Shortly after, skaters launch like a swarm of giant locusts, to descend upon the streets of New York City at dusk. The leader signals followers to take breaks at pre-designated stops along the route, so that the rest of the group may catch up, with the sweeper being the last person to arrive at each stop. The route circles back to Union Square, where a day’s skating concludes.

Skaters take a break at South Street Seaport
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Slalom bladers at Corona Park

Slalom bladers practice at a well-paved area behind Mist Garden at Flushing Meadows Corona Park in Queens. The surface of Mist Garden is quite smooth for inline skating as well, when it’s not spewing fog and mist. You will find Mist Garden right next to the Unisphere which skateboarders and bladers alike have also turned into a skating rink.

This article is not about a skatepark with street and transition elements, but I include it as a honorable mention as a part of my Public Skateparks on Long Island series. Also check out the article on Maloof Skatepark which is just 3-minute away by skates.

Slalom area with the Mist Garden and the Unisphere in the background
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Inline skating as rhythmic falls and recoveries

Some of us argue that skating consists of repeated cycles of falls and recoveries. Specifically, a skater deliberately moves his upper body such that shifted center of gravity causes him to “fall”. During this fall, he continues to glide on one skate. But at the same time he moves his other skate, the free skate, towards the projection on the ground of his shifting center of gravity, with the aim to recover from the fall by planting the free skate onto the new projected center of gravity. The process now repeats, with the previously free skate now becoming the new gliding skate.

Some of us argue that skating consists of repeated cycles of falls and recoveries. Specifically, a skater deliberately moves his upper body such that shifted center of gravity causes him to "fall". During this fall, he continues to glide on one skate. But at the same time he moves his other skate, the free skate, towards the projection on the ground of his shifting center of gravity, with the aim to recover from the fall by planting the free skate onto the new projected center of gravity. The process now repeats, with the previous free skate now becoming the new gliding skate.
A forward crossover movement seen as deliberate falling out of balance, ending with a recovery

If this fall and recovery sound like walking… well, it is walking, but with a special skating gait. And we need a specific vocabulary in order to talk about this special walking. See the illustration below.

We need a specific vocabulary in order to talk about this view of skating as rhythmic falls and recoveries.
Terminology for skating as falls and recoveries

Let’s look at the same sequence from earlier, with annotations. The skater starts out leaning to the left while gliding on his left skate. He is about to fall to the left, but during the fall he moves his right skate, the free skate, over to his left side. He catches his balance at the last second, by planting his right skate on the projection of his shifted center of gravity. I call this moment a balance moment, indicated by a red bracket.

Let's look at the same sequence from earlier, with annotations. The skater starts out leaning to the left while gliding on his left skate. He is about to fall to the left, but during the fall he moves his right skate, the free skate, over to his left side. He catches his balance at the last second, by planting his right skate on the projection of his shifted center of gravity. I call this moment a balance moment, indicated by a red bracket.
A forward crossover movement seen as deliberate falling out of balance, ending with a recovery

This may sound contrarian to the usual teachings of pushing off with alternating skates. In the fall and recovery narrative, there is no explicit pushing. There is only the body shifting balance and inducing falls. But this is just a complimentary perspective that describes the same coordinated movements of body parts.

I’ve written about rhythmic falls and recoveries in ice skating before. The same principles mentioned for ice skating apply to inline skating. This is an offshoot of the beginner guide I recently wrote: How to Inline Skate.

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How to Inline Skate

Since the pandemic of 2019, I’ve been regularly inline skating at Eisenhower Park after work. In these last two years, I’ve seen a large number of new skaters show up with a box of new skates at the park. They put on their new inline skates, and struggled around for a while. Most tried to walk around the rink by holding onto handrails at the outermost track. The brave tried to skate and fall. Very few approached me to ask for advise.

So a large number of first-time newbies showed up every week. But I almost never saw them a second time. Perhaps they went to a new park to skate. Perhaps they didn’t hang out around the rink after getting their footing, so to speak. But I suspect that a majority of them gave up.

Learning to inline skate

This article is for those who attempt to learn to inline skate. This article is what I wished someone had written for me, when I was just learning to skate. If you live on Long Island and are interested in connecting with your local skaters, consider joining r/NassauBladers at Reddit.

I learned to cruise around on level biking trails years ago, before YouTube tutorials were a thing. I figured out skating by trial and error, or I thought. I remember thinking that I knew how to inline skate.

This illusion lasted for years, until I saw skillful ice skaters at the Bryant Park ice rink one winter. Mesmerized, I picked up ice skating, and it changed how I saw inline skating as well.

Here I will share a few basic but crucial skills I’ve since learned. Hopefully this article will help beginners progress faster, and cut down significantly their frustration level. But I am under no illusion about my own abilities. I am merely an intermediate skater. I have my own next sets of barriers to overcome. Perhaps more articles will follow in time.

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Inline Skating Rink at Eisenhower Park

Eisenhower Park is one of the few places in Nassau County where an inline skater can practice at an outdoor rink when honing one’s skills, and then stroll leisurely on wheels along scenic trails when just hanging around with friends and family. The rink is accessible all year round, and you will see people there every day. However, skating at the rink in winter months is only for the most determined folks.

Demonstrating the lemon drop at the tracks in winter

If you are interested in connecting with your local skaters, consider joining r/NassauBladers at Reddit. If you are learning to skate, check out How to Inline Skate.

This article is not about a skatepark with street and transition elements, but I include it as a honorable mention as a part of my Public Skateparks on Long Island series.

This is what the rink looks like from the sky. Eight circular cement tracks surround an inner cement court with markings for baseball. Surfaces are coated, but I am not sure with what. The inner court gets less abuse and appear to have a less worn-out coating. Despite cracks, skating on tracks and on the inner court is a smooth and satisfying experience because of the coating.

Inline skating tracks and rink
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What is a 5M NaCl solution in wt% mass fraction?

What is the equivalent mass fraction of a 5M saline solution?

A 5M molarity NaCl solution is equivalent to a salt-water solution prepared at mass fraction of 24.53 wt%.

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