An open-source stethoscope that costs between $2.5 and $5 to produce • Hacker News Board

Re: An open-source stethoscope that costs between $2.5 and $5 to produce

#121

Post by bombcar » Thu, Apr 30, 2026, 12:27 PM UTC

GuB-42 wrote: post #118

rustyhancock wrote: post #68

Earlier quoted context omitted.

It's a bit of a head scratcher. It would require abject incompetence on the part of jellybean stephoscope manufactorers for this to make sense. On the other hand the reason Litmann stephoscopes are expensive is target market (doctors), build quality and amortization of cost over probably a decade of use. Stephoscopes are a metanym for doctor, and doctors don't want cheap stephoscopes. It reminds me of the product to…

There is something about using quality tools that goes beyond practical. For example, I like coding on a nice keyboard, and I think I am not the only one here. But realistically, the cheap keyboards that litter offices everywhere work just as well. Simply, I don't enjoy using them, and when it is something you work with every day on a job that pays well, you can afford a few hundred dollars worth of luxury once in a…

And the $10 toolbox needs to only be insufficient once or twice and suddenly the $200 packout makes sense.

For you or I who use the box once a year? The savings are worth the minor hassle - but if you’re using it everyday it only takes once or twice to outweigh the costs.

Re: An open-source stethoscope that costs between $2.5 and $5 to produce

#122

Post by bombcar » Thu, Apr 30, 2026, 12:30 PM UTC

throwaway2037 wrote: post #101

andrewla wrote: post #59

Earlier quoted context omitted.

When my kids were little they had a toy doctors set and the fake wooden stethoscope broke; replacing it with a real one was significantly cheaper than paying Melissa and Doug for a new one.

Hat tip. I never heard of "Melissa and Doug" before this post. I found the doctor's kit here on Amazon: https://www.amazon.com/Melissa-Doug-Doctors-Original-Pieces/... It is adorable!

They make a bunch of “old style” toys and some are quite nice, but some start getting toward the “just buy the kids the real thing” pricing.

Re: An open-source stethoscope that costs between $2.5 and $5 to produce

#123

Post by bombcar » Thu, Apr 30, 2026, 12:32 PM UTC

Part of it is this - you get hired by Anthropic making $250k a year. They give you the latest MacBook Pro, a nice office, and a $5 Walmart mouse.

It works. Probably fine.

But it’s weird.

Re: An open-source stethoscope that costs between $2.5 and $5 to produce

#124

Post by an0malous » Thu, Apr 30, 2026, 1:08 PM UTC

copperx wrote: post #97

davikr wrote: post #72

Earlier quoted context omitted.

Yes, if you're going to be using it for the next 10 years, it is worth going for the more expensive Littman if you can. However, I've heard that there are decent Chinese clones, and honestly I've used those $1 stethoscopes in isolation units and they're not terrible for basic pulmonary auscultation.

But where do they fail? What does a good stethoscope bring? better and clearer amplification?

They don't come in "pink rose satin finish"

https://www.amazon.com/Littmann-Stethoscope-6159C-Flexibilit...

Re: An open-source stethoscope that costs between $2.5 and $5 to produce

#125

Post by enaaem » Thu, Apr 30, 2026, 1:21 PM UTC

GuB-42 wrote: post #118

rustyhancock wrote: post #68

Earlier quoted context omitted.

It's a bit of a head scratcher. It would require abject incompetence on the part of jellybean stephoscope manufactorers for this to make sense. On the other hand the reason Litmann stephoscopes are expensive is target market (doctors), build quality and amortization of cost over probably a decade of use. Stephoscopes are a metanym for doctor, and doctors don't want cheap stephoscopes. It reminds me of the product to…

There is something about using quality tools that goes beyond practical. For example, I like coding on a nice keyboard, and I think I am not the only one here. But realistically, the cheap keyboards that litter offices everywhere work just as well. Simply, I don't enjoy using them, and when it is something you work with every day on a job that pays well, you can afford a few hundred dollars worth of luxury once in a…

That is also my productivity hack. It reminds me of video games that gives you reward cues for doing something. Psychological tricks to massage your brain and get you hooked. That's why also like to buy nice stationary. I always look forward to use my notebooks and pens.

Re: An open-source stethoscope that costs between $2.5 and $5 to produce

#126

Post by bonsai_spool » Thu, Apr 30, 2026, 3:00 PM UTC

dzhiurgis wrote: post #79

bonsai_spool wrote: post #69

Earlier quoted context omitted.

> How long do they last? Looks like pretty solid piece of equipment, but are they damaged easily or simply clap out after few years? They last forever. Why would they break? This is like asking how long floor speakers last.

Stereotypical image of the doctor is that they carry them over their neck 24/7, so that alone would destroy them pretty quickly.

> Stereotypical image of the doctor is that they carry them over their neck 24/7, so that alone would destroy them pretty quickly.

Why do you assume this? Have you ever used one?

Re: An open-source stethoscope that costs between $2.5 and $5 to produce

#127

Post by mythrwy » Thu, Apr 30, 2026, 3:14 PM UTC

colinbartlett wrote: post #2

I was shocked to see that a "brand name" stethoscope is $100+ and even generic ones are $30.

$100? So, like 4 aspirin tablets US hospital billing prices?

Re: An open-source stethoscope that costs between $2.5 and $5 to produce

#128

Post by zawaideh » Thu, Apr 30, 2026, 4:07 PM UTC

KnuthIsGod wrote: post #99

Amazon in India will sell you a pretty reasonable stethoscope for for $3. Assuming the usual Amazon, distributor and retailer markups, these probably cost around 50 cents to make in China. https://www.amazon.in/BPL-Medical-Technologies-ST-01-Stethos... Many poor countries are perfectly capable of manufacturing their own medical equipment Background: I have worked in hospitals in Bihar & Vellore Tamilnadu, and have un…

This has been used in Gaza to make their own due to Israel’s blockade.

https://logicmag.io/bodies/tarek-loubani-on-3d-printing-in-g...

Re: An open-source stethoscope that costs between $2.5 and $5 to produce

#129

Post by Animats » Thu, Apr 30, 2026, 5:33 PM UTC

throwaway2037 wrote: post #105

Animats wrote: post #67

Earlier quoted context omitted.

Right. There are plenty of cheap plastic stethoscopes on Alibaba. There are even metal ones in the $2 range. If you want to bang out simple parts in quantity, 3D printing is not the way to go.

Up next: 3D metal printed version!

Something I'd like to see from the hobbyist community: DIY injection molding. Injection molding is a process where the first one is a huge amount of work, and then you just bang them out for a few cents each. Which is why most of the world's cheap stuff is injection molded.

TechShop used to have the machine for it, but it was very rarely used. The injection molding machine was about the size of a benchtop drill press. It had fixtures to hold two dies, a pressure pump, and a guard around the molding area in case something went wrong.

There's an automated one coming out as a kickstarter. Pre-order for $6500.[1]

Now you need to make injection molding dies. This requires a milling machine, and is much easier with software support. The commercial software for planning injection molding is Autodesk Moldflow, but that's overkill for simpler projects. TechShop had that on their computers, but nobody ever used it. There's something called OpenFOAM, but it's not a nice GUI program.

[1] https://www.micro-molder.com/product-page/micromolder

Re: An open-source stethoscope that costs between $2.5 and $5 to produce

#130

Post by matheusmoreira » Thu, Apr 30, 2026, 7:41 PM UTC

f1shy wrote: post #112

hex4def6 wrote: post #66

Hmmm. Looking at: https://journals.plos.org/plosone/article/figure?id=10.1371/... I'm not sure I believe the graphs. For example, here's another frequency response chart of some stethoscopes: https://www.researchgate.net/figure/a-Frequency-response-of-... How is it that professional stethoscopes can be that different, and yet this 3D printed one can match a gold-standard one almost exactly? From what I can tell there…

You can measure all the parameters you want. The question is: does it really matter? I know many doctors, and one of my favorite questions is about stethoscopes: I have unanimously the answer "I could just roll a piece of paper and if the room is quiet enough, I can do my work". My grandpa used one made out of wood, just a cone. Once, I was fascinated by a Littmann, with bluetooth audio, I told a friend doctor, that…

> I could just roll a piece of paper and if the room is quiet enough, I can do my work

That is true. The job is certainly doable. It's also possible to press one's ear against the patient's body to directly listen to the sounds without any tools whatsoever. Stethoscope was itself invented because a male doctor doing that to a woman's chest was uncomfortable for obvious reasons.

There is some kind of difference between a good littmann and a cheap stethoscope. My experience is that the important sounds are just easier to hear with the littmann. Would love to know why that is, and why the cheap ones just can't seem to match it.