Sleeve cap ease is bogus (2005) | Hacker News Reader

Sleeve cap ease is bogus (2005)

fashion-incubator.com

242 pointsdjsumdog39 comments

The pattern maker who got the stripes to match in both dimensions probably used a textile CAD program to do it. There's software for this. High end: [1] Low end: [2]

"Pattern Design Software (PDS) 3D -- A set of 3D tools that display virtual samples in an innovative 3D digital environment that allows you to fashion your garment and make quick alterations at the click of a button, powered by photorealistic rendering for a true-to-life visualization."

"Inspect simulated cloth using a tension map to view the exact value of tension, distance, and stretch..."

These tools are also used for clothing for characters in games, movies, and virtual worlds. Marvelous Designer is often used for Second Life clothing.

[1] https://optitex.com/

[2] https://www.marvelousdesigner.com/

It also looks like the top two horizontal stripes on the back are matching the vertical stripes on the sleeve rather than the horizontal stripes on the sleeve.

I would be more convinced if the example was a striped coat rather than a plaid coat.

It is interesting that my comment got both upvoted and downvoted. I didn't know that people on hacker news knew that much about sewing!

I will just say what I thought was too technical to say. I have actually sewn sleeves and have done pattern matching between the body and the sleeve.

Two things impact the pattern matching.

Most of the ease is in the top of the sleeve cap and not in the body of the sleeve cap. The first thing I do is make sure the pattern is as far away from the sleeve cap as possible. Then I check if I can fool the eye. If you look closely at the plaid closest to the top it is shifted slightly which was disguised by matching the vertical stripe instead. The maker of the coat did both of these things. So - nothing was proved since this is normal sewing practice.

The second thing that impacts pattern matching is the stretchiness of the fabric. Pattern matching in knits is very easy even with ease. I don't think this was used in the particular coat.

I am very surprised that the author thought that a photo from an unknown manufacturer proves that easing was not needed. They could have easily proved it by sewing something. This leads me to believe they don't know as much about sewing as they implied.

Some of my background: I am a retired software engineer. The first half of my career was in 2d and 3d graphics rendering. My mother taught sewing professionally with a home economics degree from UC Berkeley (back when they had such a degree). She taught me as a child how to pattern match plaid. I have been fascinated by the math of sewing - but only as a hobby.

Marvelous Designer is not low end. Rather it is focussed on pattern making and simulation of clothes for VFX and games.

It has a big cousin from the same company, CLO3D [1], which is squarely aimed at professional pattern making.

[1] https://www.clo3d.com/

As a wizened old programmer AND a person who has once sewn his own dress shirt, I'm not sure what to think of this. I recall that easing while attaching the sleeve seemed unavoidable.

That said I am glad this made it briefly to the front page of HN where I could see it. Thanks for posting! This is interesting.

I will add that I think the argument being made is: it is received wisdom that if you don't ease the seam, you can't match up a pattern, and they are refuting that. If I understand this correctly I think this article is right, there are geometric ways around that ... but I think the original wisdom applies to a context of fashion surrounding the sleeve cap. The way that the sleeve is attached is itself subject to fashion, such that easing is partly to achieve an effect, and not just to match things up.

Respect. Sewing a dress shirt is hard. Hell, just getting the buttons straight and reinforced is hard.

I still have no idea what a "sleeve cap ease" is, but reading that post is fascinatingly esoteric.

that's life 95% of the time. many people have an opinion, but most of them don't have the depth needed. the important thing is that you 1) are curious 2) you keep learning.

In regards to this, what approaches can people take to become more T-shaped? I consider Hacker News a very good resource for learning, however, I sometimes feel overwhelmed by the amount of information I miss out on.

Something that I like to do is try to come up with every topic that I can possibly think of. I just thought about what I might interact with on an average day and came up with clothing design, restaurants management, window installation, gasoline manufacture, and book binding. And then I try to find out the bare basics about each topic, no matter how weird or esoteric.

This sounds like a great topic for an "Ask HN" post.

The sleeve cap is the top portion of the sleeve (the bell-shaped section on the left hand, i.e. the "wrong way", image in her diagrams in this article), and where you attach the sleeve onto the armhole.

"Ease" refers to the extra fabric in the sleeve cap. When I was taught to sew, I was taught that the sleeve cap should be larger that the arm hole, and then you have to do a whole bunch of cinching and stretching to get to sleeve sewn on correctly. The goal is for the sleeve cap to accommodate the shoulder without looking bunched or poofy, but (at least for novixe me) my sleeve seams always looked weird and messy.

This is an example of one of those rare posts made by an expert that is generally understandable by anyone, but still gives glimpses into the mastery of the work by the author. Great read, love old posts like these. I have never even thought about how it's a challenge to get patterns to line up correctly on clothing.

> So on the face of it, what does this photograph tell you -other than that the model is right-handed?

That's some Sherlock Holmes stuff right there, to me at least.

I assumed the whole photo would show the woman holding the bag in the right hand

You can tell something is being held in the right hand from just this part.

Why does that make a person right-handed? Holding something in your non-dominant hand keeps your dominant hand free for things that require more dexterity.

Agreed. I don't think it does demonstrate right-handedness.

Unless you're carrying rocks in it, holding a purse will not pull your shoulder down. They are saying the slump indicates the dominant side and not the effect of weight.

Are you sure that's accurate? I think carrying an average weight purse would cause some amount of droop on that side.

I assume that conclusion is drawn because of how much lower the right shoulder is.

A physical therapist told me that the shoulder of the dominant hand tends to be a bit lower. It's probably not common knowledge, but patternmakers and tailors would come across it in their line of work.

I assumed it was because of the hair.

This is fascinating, but I'm not nearly sewing-literate enough to fully follow it. This is the best resource I can easily find for exactly what is being discussed: https://seekatesew.com/sewing-101-ease-sleeve/ I guess people literally make the circumference of the arm hole in the sleeve smaller than that in the torso portion, and compress it to fit in the process of sewing them together.

It's the reverse. The circumference of top of the sleeve is cut larger than the hole in the torso.

Dammit. I knew that and still managed to write the opposite.

There's something really nice about people who know their stuff explaining things. But this is not it.

Everything Kathleen writes is abrasive, borderline insulting to the reader. I want to read her work, I have her book sitting on the shelf here. But I wish someone would explain to her that kindness goes a lot further than mockery.

Also, sleevecap ease is obviously not bogus. You can just get away without it on this type of fabric.

That may or may not be the correct pattern for a sleeve but their reasoning seems like bro science to me. Your arms hang forward because when you raise your arms your pits are facing you in the mirror? The person doesn't seem to have a good understanding of the shoulder complex.

Their actual argument is that the arms don't sit exactly to the sides of the body like in a Lego man, which is true. The armpit example is just a little exercise people can do at home to convince themselves of this fact. If you don't like it, just take a look at a human being. There is more flesh in the back than in the front, the arm has a wider range of movement in the front, etc.

I also take exception to your use of "bro science" as a derogative. Bro science is most common in the fields of exercise and nutrition, and if you look at the resulting bro bodies, they are strong and athletic. Meanwhile, academic nutritionists have presided over a public health disaster that has left the majority of Americans grossly unhealthy and obese. The experimental conclusion is that bro science is far superior to academic science.

I agree with your first paragraph.

I like the snark in the second paragraph, but I don't think you can draw your conclusions so easily.

Both bro science and academic nutritionists tell you that exercise is good for you. Bros are much more likely to take that advice than the average person.

Whether that different predisposition explains the whole difference in outcomes or not is a much more complicated question. It's all terribly confounded.

(You might very well be right, but your argument ain't tight.)

No, their actual argument is:

> Now, if you doubt your arms are on the front of your body, stand in front of a mirror and raise your arms -in their most comfortable position over your head-…where are your armpits? If you’re like every other human on the planet, your armpits are facing you, dead center. If your arms really were on the sides of your body (the way sleeves and armholes are cut) you’d have to turn sideways to see your armpits.

Which is a load of bollocks. It doesn't take more than a minute or two of studying anatomy diagrams to see that. Are they centered horizontally like a lego figure when viewed from the side so they bisect the volume? No, in fact the shoulder joint is BEHIND most of the volume in the torso when viewed from the side; so the humerus hangs roughly in line with the spine. Most of the rib cage(and pecs), abdominal cavity, and etc are forward the head of the humerus.

The real reason the you can see your arm pits when you lift your arms over your head? The insertion point for the pecs in the humerus draws closer to the mid-line as the arm is externally rotated and raised while at the same time the scapula is rotated up and out pushing the lateral border and all the meat away from the mid-line. Effectively the front wall of the "pit" collapses exposing the built up back wall.

> and if you look at the resulting bro bodies, they are strong and athletic

I mean.. That's a primary ingredient in the spread of broscience isn't it? The credibility "results" lends to bullshit? cough supplement industry cough.

(2005)

It was true and applicable in 1805 and will be true and applicable until human bodies are not in fashion.

It will even be true and applicable once machines scan you and make your clothing directly to your own form; it will just be part of what the machines are programmed to do rather than what a human has to take into account.

I've never really understood the need some HN readers have, to insist on a date on anything that wasn't published relatively recently. Especially articles about things that do not change with time.

Maybe every post should have the article's date, so when I read old HN posts there is no room for confusion.

The site is called News so I think it’s worth mentioning when something isn’t news.

It's often a useful bit of context. It's not simply a matter of the validity of an article, but more that being closer to or farther from an event or discovery often changes how it's framed and discussed. It also helps set expectations about what related things won't be discussed because they hadn't happened at the time.

(it also helps clarify that nagging feeling of deja vu; "didn't I read this a few years ago?")

Its also an obscuring factor. Articles with dates specified don't do nearly as well as articles that appear contemporaneous. You can see this with the performance of titles that get modified by the mods, they seem to slow down significantly after the date is added.

> Obviously, the total length of the sleeve cap must be equal to the total length in the armhole, otherwise these stripes would not be matching.

Not necessarily. The photograph only shows that the pattern lines up at the back, it doesn't show that it lines up at the front.

Not a fan of articles whose main line of argument is vague insults about how stupid people are. It projects insecurity and lack of confidence in their claims.

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