@bea ... please tell me taxpayer dollars were not spent on this

@Elizafox i mean... i have to assume they were but i don't really see why it's a bad thing?

@bea cause this would be a frivolous use that could be better put to something else, given there's not much to go around? (thanks government)

@Elizafox frivolous how?! if you can make good microfluidic systems from this stuff it's important!

@bea ... you need a microscope to do it

those things are not cheap

you might as well 3D print this stuff or focus on making that possible

@Elizafox @bea that's literally what the paper is about? using LEGO as a proof of concept for micro-milling 3D-printed components?

@Elizafox the paper is LITERALLY about why 3d printing is unsuitable for things and why using stock injection molded parts can have advantages?????

@bea @Elizafox irrelevent nitpick too: it's the micromill that's gonna cost you, not the microscope

@er1n @Elizafox the mill is only 5k, microscope probably similar honestly

@bea @Elizafox hmmmm wow
but yeah the whole point is that you just _can't_ 3dp most microfluidics stuff because 3d prints end up weird and ridgy and leaky and terrible
and this is a cheap way of actually making something that works lol

@er1n @Elizafox yeah the dominant tech is still lithography which... is even WAY more out of reach than the mill and microscope

@bea @Elizafox hmmmm i wonder if this was grad students doing this or if it was a UROP project

@er1n I want to fav this but...i also dont wanna lose other things i faved to the list of doom, but ty for the supporting statement.

@er1n @bea that's what I'm saying, research should be funnelled into doing that, not doing this with lego, which to be honest is more a toy than anything that will be used in production.

@Elizafox @er1n @bea I know people who are trying to build microfluid experiments out of styrofoam, to put in a cubesat; I think they would /love/ to be able to use Legos.

Also, the whole point of the paper is “hey, we can do this stuff with injection-molded parts”; it just so happens that injection molds are /expensive/, and Legos are cheap.

@Elizafox @er1n @bea Doing tests based off of "toy" projects is often how you get towards understanding a problem domain so that you can get to actual production later.

Also why metacircular evaluators are popular with language design researchers... of course you would never use a language written like that, it's just at toy, but you can test out language *ideas* fast and later turn them into production systems.

Fast iteration FTW!

@bea welp i didnt know what the paper was about but...just from the discourse i worked it out..xD

@bea oh....I totally missed the expand button on the first toot....sorry Bea.

@LottieVixen it's all good pal no worries

@bea so all I saw was "current paper im reading" then the second toot and thought "weird jump but...okay"

@LottieVixen maybe we should make that collapse indicator a little louder

@bea I was literally just thinking perhaps a white box behind it when folded, turn to grey when expanded?, white or light blue anyway (same colours as the left hand side to keep the colour scheme)

@Elizafox @bea why design something, if Lego could possibly already do the job? i think research is the better idea.

@Elizafox @bea It's possible to 3D print microfluidics, but the tech for it is currently far more expensive than a good optical microscope (and as @er1n mentionned, your consumer-grade 3D printer won't cut it)

Also, I don't see how exploring pathes to cheap microfluidics that work today is frivolous.

@bea @Elizafox I love Lego, this is great

@bea @Elizafox dear govt: plz spend more money on interlocking injection-molded blocks based research

@cwebber LEGO exists, and it might be cheaper, but isn't the downside to LEGO that it is patented in design?
Or maybe memory doesn't serve me right.

@ng0 pretty sures the patents have expired... in fact IIRC that's one major reason Lego moved towards so many "character license deals", because they wanted to still have the market cornered in some way

@cwebber yeah: https://www.cnet.com/news/lego-you-are-dead-to-me/ one of the first links in my searx search.

@cwebber I have this giant terrible collection of LEGOs (and LEGO Technik) from the late 80s and 90s and after many years the boxes containing them broke down. I'll need to get a new (and bigger) box soon. I have no use for it anymore, but sentimental values.

@cwebber I didn't fix up the pictures in the current documentation, but I'm still working with LEGOs:
https://gnunet.org/system-architecture-with-legos
:)

@bea so how is the precision of lego, don't leave us hanging

"Bricks were fixtured in the mill using a base made of other LEGO bricks. This
allowed the bricks to be securely mounted to other bricks, and repeatably re-positioned.
An initial zero point was located on this fixture and then bricks were freely attached and
rotated on the fixture for milling. "

bricks all the way down baby

3/?

@bea
:D
Oh my gosh this is such a fun apparatus.

The gap between nominally identical bricks was found to be roughly proportional to the brick size, with 2-post bricks having 172 µm gap width and 8-post bricks having µm gap width, or 177 µm gap width on average for all bricks. When mounted to a baseplate, the standard deviation in gap width was 7 µm for 2-post bricks, 25 µm for 8-post bricks, and 25 µm variation between all bricks (or average single-brick variation of 14.4 µm) https://glitch.social/media/siyOFFIx6lt4wwXHTe4

@bea this is beautiful...heck

@bea oh! This is useful to me! For an entirely different reason! I was making a LEGO renderer but I just chose the gap width arbitrarily, but now I have a real-world reference point! Thanks!

That's a lot of exclamation points!

@bea (also you left out one measurement, but it's ok)

@impiaaa oh, what do you need? or did you grab it already (;

@bea "…and 8-post bricks having µm gap width"

@impiaaa 252 !

sorry it looked like a line number!

@impiaaa lol amazing

@impiaaa i bet if you asked nicely they'd give you their solidworks models (;

@bea eh, I already have the 3D models, and I'd have to get SolidWorks for that to be useful anyway 🙂

@bea https://github.com/impiaaa/blender-ldraw/commit/cad684e289888a372e7e5c2adb93122a726e2d52

oops that was 4/? forgot to number it

"Interestingly, the repeatability of fluidic bricks with O-rings and sealing film was measured to be 1.6 µm and 1.0 µm (Fig 3, without and with a top clamping brick, respectively). ... suggesting that the O-ring provided a further constraint due to the force exerted against the neighboring brick. "

one fucking micron repeatability!

5/?

@bea hey bea i have no idea what any of this means but you're good and i love you

@kibi <3

@kibi @bea lol BIG MOOD

@subunitA YAY!@!

i'm glad!

it is so worth reading the figures are amaaazing. i posted one and honestly i wanna post them all but i feel like i prrrrrrrobably shouldn't

@alienghic yes! it's great! i wanted to post more of the figures here but figured i shouldn't...