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RepRapMicron

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445 pointsRobotToaster74 comments

I feel like we're reliving the late 1790s again, back then you had Ramsden figuring out how to divide the circle into into seconds of arc, taking the marking of scales from an artform into something that could be manufactured reliably. Maudslay with his thread cutting lathe took the making of screws from a manual process pawned off on apprentices to something that that could be done in mass production. Wilkinson's boring machine made it possible for Watt to build a pressurized steam engine.

All of these tools are based on things that were one-offs of earlier efforts, and turned into practical machine tools by someone that history chose to remember. We're now at the point where making things by manipulating individual atoms is something a determined amateur can do, it's amazing!

I find myself fascinated by the Wyler Inclinometer, which uses a thin copper disk with spiral arms as the basis of a differential capacitor, and when complete, resulting in a device that can used to calibrate a granite surface plate. It can typically measure 1 micron/meter of deviation.

We now have 3d printers that can reliably make almost anything you want by fusing filament, or stereolithography, or fusion of metal powders. You can buy desktop 5 axis CNC machines. There are control systems available to let you build almost any type of machine tool you can imagine, in as many axis as you want.

We've got software defined radio, cheap atomic clocks, transistors that can switch megawatts, all within reach of a hobbyist.

What an amazing time to be alive.

Do you have any links/sources about that Wyler Inclinometer you could share?

I'm trying to find the original very informative video from a decade or so ago, but I've found this pdf[1], which mentions the heart of the mechanism as a disk/spring on page 19. Some product training in this pdf[2] touches on the mechanism as well, as does page 39 and 156 of this pdf[3]

Here's a PDF from Wyler's own site[4] about the Zerotronic, with the mention of the "pendulum" on page 7.

[1] https://ftp.wylerag.com/Downloads1/WYL_e_wyler.pdf

[2] https://www.someco.fr/wp-content/uploads/2021/08/zerotronic_...

[3] https://symetrie.fr/wp-content/uploads/2023/09/WYLER_Catalog...

[4] https://www.wylerag.com/fileadmin/pdf/manuel/zero_e.pdf

> We now have 3d printers that can reliably make almost anything you want by fusing filament

I bought a cheap, used, Bambu Lab A1 printer after reading a comment here on HN a few months ago saying that it was basically now "download and print". And it's just that. Not saying Bambu's practices are great: what I'm saying is that 3D printer now work better than inkjet 2D printers ever did.

> What an amazing time to be alive.

I agree. In a few days I learned to model 3D pieces myself in OpenSCAD (and there are many other options than OpenSCAD) and I've already done "print in place" pieces (pausing the print, inserting a metal piece, continuing the print) to fix stuff around the house (and in the cars).

If you had told me 30 years ago that I'd be 3D printing pieces and getting help from LLMs, I wouldn't have believed it.

Openscad feels very comfortable for programmers. Some years ago I tried to use freecad first, and I felt the GUI was getting in the way. (I heard it's gotten better more recently) Declaring geometry in a programming language with variables, functions (err "modules"), for loops etc. is much more intuitive to me.

Openscad is great for flexible parameterized models as well. However, fillets and chamfers that are just a couple clicks in Fusion 360 are a major undertaking in openscad once your shape is more complicated than a cube. That alone basically kills openscad for me for most use cases

Freecad used to be way outclassed by Fusion, but seems to have made major strides in recent months to bring it closer to the state of the art (even if it's still not quite there)

I thought so too but then I discovered the BOSL2 library and all kinds of others ... makes cubes with round edges so much easier :)

https://github.com/BelfrySCAD/BOSL2/wiki/Tutorial-Rounding_t...

I found it's not so bad to do fillets and chamfers as a for loop that gradually increases or decreases a dimension, then put it as a module to make it into a reusable high level primitive.

many other code-cad tools exist now too, my personal favorite is buld123d - python (and cadquery)

It might be that I haven't put enough time in, but, I haven't found it as ergonomic as SolidPython (OpenSCAD wrapper).

Have you found that it becomes more natural?

yes, but I may have not used openscad enough.. (I use mostly build123d and some freecad, barely used openscad)

As a programmer, I wasn't confortable with OpenSCAD, and ended up moving to Fusion360 like almost everyone else.

The problem isn't the scripting, I am a programmer, I am fine with it. The problem is that I had to do all the math myself, or worse, use hardcoded values when it should have been computed. That is, for example, if I want a hole in the middle of a square face, I want to be able to say "I want a hole in the middle", whatever the language is, without having to solve a math problem.

That's why I prefer constraint-based modeling, like what the likes of Fusion360 offer. Paradoxically, even if it is graphical, it feels more like programming to me than OpenSCAD. In Fusion360, the model is defined as a sequence of instructions (the timeline at the bottom), these are not lines of code, but it is a program. That sequence of instructions can be manipulated, and you can use variables. And it is easier to define things programmatically than with OpenSCAD, where you often have to put in values by hand, because the math is too complicated without an constraint engine like Fusion360 has.

FreeCAD and Fusion360 both have scriptable APIs. CAD models are just documents.

I think we tend to underestimate the importance of precision manufacturing in science.

For example, we attribute general relativity to Einstein, fair enough. We generally acknowledge that he built his work on mathematical foundations by Lorenz, Minkowski, Poincaré, Riemann,... But what really made general relativity into a concrete theory rather than just a cute math problem is that it solved the problem with the orbit of Mercury. And the reason we knew there was a problem with the orbit of Mercury is that we had instruments with enough precision to measure it, if we didn't, then general relativity would have been useless.

Newton couldn't have come up with general relativity, not because of math or because he wasn't enough of a genius, but because with the level of precision their instruments had, it had no reason to exist.

And the channel's preceding few videos covering the development of the prerequisite technologies.

This video was amazing, thank you for sharing. What are the main applications for this technology with a home setup?

affordable housing for everyone. a bit tight but it's a start

Woah, this is so cool

Thank god, in 18 months we can start making our own RAM.

Just need a garden shed: https://youtube.com/watch?v=HfSO-LCKmrA

That is proper mental. And extremely cool

The guy with the shed is a founder and a CTO of a semiconductor company, and uses his home lab for business.

Sam Zeloof also created his own transistors, then founded AtomicSemi/fab2: https://youtube.com/watch?v=IS5ycm7VfXg

inspired by Jeri Ellsworth, who also documented hers on Youtube: https://youtube.com/playlist?list=PL5DCEA197C1C07A2D

Saw Jeri demo some of her early transistors, it was one of the most inspiring things seen in a hackerspace… 15 years ago now? Sheesh. Glad to see AtomicSemi/fab2 in existence, that is a relief. We simply have to get desk-side fabrication happening, faster, imho ..

Sam Zeloof's new company is a serious business. He went from studying electrical engineering at CMU and doing semiconductor fabrication as a hobby, to running a well funded team to produce equipment for mini-fabs.

It is actually a great example which shows the difference between cobbling something together in a garage, to produce a one-off demonstration, and having a mini-fab which is capable of delivering the results reliably. The difference in the required effort is many orders of magnitude.

The "RAM in a shed" guy started with a Ph.D. in semiconductor technology, and was running a company before he made the improvised lab at home and started to make videos about it. He uses the lab to test some of the steps for the specialty devices which he invents.

Also seems to mostly go off of Hacker Fab (https://docs.hackerfab.org/home)

Wow - another example of just how big the Internet is. Never heard of this guy and that seems kinda unfathomable given overlap in interest.

I think it's more of a proof that youtube's search and recommendations algorithm is rubbish.

To be serious, maybe not 18 months but 2-3x that.

I know it is a preposterous proposition to think this thing could create a 1/1000 version of itself, hence 1/1,000,000 3d printing, but why?

Calling it a RepRap, with full explanation that that means a printer that can print itself, does make it sound like it could be a goal

But even if you could get a positioning system that small, I'm pretty sure you can't scale resin printing down three orders of magnitude smaller than this printer. Maybe a tiny CNC?

Or more likely they refer to eventually printing the mems devices used in the printer

None of the reprap 3D printers can fully make themselves. They all still need additional parts that can't be 3D-printed, like motors and controllers.

I think some basic versions of both motors and circuits are 3d printable now. I doubt good enough for driving a reprap, but perhaps later.

Supposedly "the answer" is a discarded engine block: https://makezine.com/article/maker-news/patdelany/

"Open Source Muti-Machine": The heavy, ultra-stiff mass of the cast iron dampens vibrations and forces the cutting tool to move in a perfectly straight, micron-accurate line dictated by the factory-bored cylinders.

Ask an AI about it, but conceptually it's an amazing concept. There are probably billions of "nearly micron-accurate" machines, and if you're 1000% repeatable 90° then the world is (eventually) your oyster.

Vik, the guy who made this, is one of the original reprap people

A mechanism that works at scale X doesn't necessarily work at scale Y.

Different forces and material properties are all at relatively different levels.

The one I know offhand that will mess with stuff is the square-cube law. If you double the linear dimensions of something, it's twice as big, linearly, but 4 times the surface area and 8 times as heavy. The strength of anything that depends on area (like friction) won't scale at the same rate as anything that depends on mass or volume or anything.

Not to mention I'm sure this thing can only print a few different materials. Unless those are also _all_ of the materials it's made out of, it couldn't even make itself.

whats the practical impact of this law? regarding friction there is probably the screws that need to be fixated with a glue?

There are many. At larger scales, weight and inertia dominate, but also magnetic fields matter much more than static electrical fields for generating force. At smaller scales viscosity, friction, and surface tension dominate, and electrostatics are much better at producing forces. Small-scale structures are often much 'stronger' than you would intuitively think (if you've heard the fact that ants can lift 50x their body weight, the square-cube law is why. A dog-sized ant would not be able to lift a car, or even breathe).

For this specifically, you would be looking at a radically different structural design, probably entirely flexural and without using traditional magnetic motors. Look at how MEMS design works in practice for an idea (though MEMS also tends to be constrained by current manufacturing techniques which push everything to be very planar).

It's why elephants have thick legs and are barely able to move themselves, not to mention jumping. And spiders and ants have needle-like legs and can lift stuff many times their weight or jump many times their length.

It's also why there's no gigantic walking robots and anything large moves on wheels or tracks.

It's also why so many insects fly and flying drones and RC planes are easy. You can make a pizza box fly if you glue engine with a propeller to it. No engineering required. But big aeroplanes are hard.

The history of precision machinery is a steady ladder of using old machines to produce new more accurate components, and then new more accurate machines.

But simply making something smaller is not synonymous with it automatically becoming more accurate or capable of achieving higher resolution. If anything, very high precision machines are typically larger in size than the less accurate ones.

In a series of lectures in 1938, tv inventor Philo Farnsworth explained the need to develop "the tools to make the tools to make the tools" to make high tech stuff. He originated the phrase.

Scale matters. For example, at large scale you might be able to essentially ignore the friction between two materials, but at 1/1000 scale it might be the same order of magnitude as the forces expected during operation.

While a large piece of sheet metal might slide down a given ramp, a 1/1000 scale bit of foil of that same metal would probably just sit on that same ramp and not move.

There are lots of constants that, by definition, don't scale.

You can only print brackets that join frames together with help of screws, not electrical and/or mechanical components. The latter two must come from AliExpress/Amazon, and 1/1000 scaled ones that do not exist have to exist for that to work.

I see a lot of micro-chip designs that are so cool, but they just exist as a design in some software on our computers. If this printer can allow cheap and sustainable printing of chip designs, then the hardware field could take a very interesting turn!

That's so cool, I see no reason you couldn't use a uv-sensitive conductive resin. Does anyone know more about this?

I did not expect this would be achievable to such tight tolerances - this is very impressive. Excited to see a new wave of micro-manufacturing in our future

Does this mean we can print vinyl records?

It’s a fun thought experiment! Napkin maths assuming max 78RPM at 300mm, min 33RPM at 80mm (I think inner groove is bigger than this but wateva) gives ~3 to ~30 microns for half-wavelength of 20kHz (not that 20k is really stamped into vinyl). Actually, not bad.

Amplitude though, 78s are the best case scenario, and assuming mono for simplicity, they have lateral displacement of about 76 microns peak to peak. So assuming 1 micron resolution that’s just over 6 bits of dynamic range absolute best case. Crunchy.

Dodgy maths aside there are lots of reasons this would not produce a good sound. There are maybe clever things you could do with a spinning bed or something? but even then.

At that point though even a normal analogue cutter head will be easier!

See lathetrolls.com if this particular kind of masochism interests you.

I had no idea this kind of precision was possible with parts that are not particularly advanced. Most of my modeling and 3d printing is entirely AI driven these days. With this stuff, I could make even miniature parts and screws and so on. I’m a late adopter, so I’ll have to wait the 10 years or so before it reaches current Prusa/Bambu performance but it’s exciting nonetheless.

It's because it's only 8mm cubic volume.

But you can get etched glass scale encoders that will give you 1um accuracy for basically nothing these days (IE <50 bucks).

You'd still be better off just using cheap linear motors with encoders built into the rail though.

Encoders are cheap, even interferometric setup is possible to do at perhaps <$300 if you happen to live near the NeHe rust belt. Actuator backlash and stiction will still be a problem. Good actuators are expensive. Solving backlash is what is nice about this setup.

Sure. For positioning a microscope point to point the backlash wouldn't matter. For an extrusion head it kind of matters. Still not as much as it would with a cutting head, but it is nice to solve it

Okay my tinker-lust has been aroused! Can someone tell me what I can make with this thing so I have an excuse to build it?

If you get this to print conductive resins you could probably build a number of mems devices. Accelerometers, gyroscopes, tiny speakers

Being able to make structures this small could maybe make DIY inkjet printers viable, if you can simplify them enough?

The most exciting are the applications nobody has thought of yet

Core memory.

I wanna know why piezoelectric actuators aren't used for more of this sort of thing. They can apply a decent force over a scale of tens of micrometers easily, or hundreds with careful design, and have force feedback too.

These aren't exactly RepRap-friendly. The piezo buzzers are too soft. For a proper multilayer piezo actuator you have to either go to Thorlabs (a bit expensive) or other manufacturers (either expensive or "don't bother us until you are ready to buy a few thousands"). AFAIR MLCC ceramic capacitors actually can make half-decent actuators, but not sure if these are suitable for precision position. Baking your own would be doable, but who wants to deal with lead? And once you got the chips, there is another problem: how do you couple it to a plastic flexture? "Adult" stuff uses wire-EDM-cut metal flextures. While not completely impossible to DIY, wire-EDM a whole undertaking in itself, and an expensive one.

Piezos are sure the way to go for a fab-in-a-shed youtuber, but not yet for those who want to make it reproducible by others.

One may buy the +-0.28mm piezoelectric actuator stacks out of China for $15, but the high-voltage drivers are not amateur friendly. =3

Really? I was under impression 100µm is state of art.

Who knows what was inside the box for sure... ymmv. At the time, we ended up going with a vacuum rated kit (https://nanomotion.com/ .) =3

I've worked with piezo actuators to align optical elements. They have great resolution, but they suffer from non-linearity, non-repeatability and a lot of hysteresis. Making motion accurate then becomes a problem of having encoders that can measure the position of your device with the required accuracy.

Some people do when building AFMs, but the piezoelectric stack voltages to get a few mm dynamic range are often around 160v to 600v.

After playing around with several options, piezoelectric was the path I chose for a sub-micron stage. It took a bit of research, but it does make things much easier when done right.

Most hobby work is kept private now... due to safety issues with people without lab-training attempting complex builds. Indeed, a few fools still die every year attempting things they saw on you-tube ("Lichtenstein burning" etc.) =3

You still need the position feedback and you're almost certainly going to need to make a two-stage coarse-find design, which is a pain.

Just for reference - another post on the same topic about the video linked by CarVac.

https://news.ycombinator.com/item?id=50140001

omg, ive wanted a precision computer controlled flexure motion system for yearssssss. i may also just really love tiny tools and devices.

So that's existed for a long time in the form of OpenFlexure. The microscope is a pretty easy / fun build.

Wow that sound promising. I wonder if such devices might, in the future, simplify the process of creating electronic components.

Very cool, and I understand the off the shelf parts ambition, but what are those usb microscopes used for? These are absolute garbage (but light weight).

To see the print? Weird comment.

The op asked because a usb microscope is basically unsuitable for seeing something this small with much clarity. From other replies it sounds like the purpose is for automated positioning which makes more sense.

Phisics dictate they have a small depth of field but they can be absolutely incredible.

Sounds like they are used for homing. For that they just need to observe a tiny spot at known distance with high resolution

To look at the output they recommend a separate regular microscope

People are still doing RepRaps? I thought everybody had pretty much settled on Bambu printers, which are to small-scale manufacturing what the MacBook Pro was to open source: the "yeah, openness and decentralization are nice and all, but I'll take proprietary if it's easy to use" option.

Imagine yourself, not everyone is willing to make the tradeoff. Also, fuck bambu so much.

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