kristianpaul has quit [Remote host closed the connection]
kristianpaul has joined #qi-hardware
kristianpaul has quit [Ping timeout: 244 seconds]
xiangfu has joined #qi-hardware
kristianpaul has joined #qi-hardware
panda|w530 has joined #qi-hardware
unclouded_ has quit [Ping timeout: 245 seconds]
arielenter has joined #qi-hardware
michael_lee has joined #qi-hardware
unclouded_ has joined #qi-hardware
<wpwrak>
hmm, with scope and signal generators converging, i wonder how long until proper multimeters will also be integrated. the higher end DMM already crawl, feature-wise, in the direction of scopes (frequency measurement, trend plots, etc.),
<wpwrak>
while for example agilent have a DVM mode in some of their scopes. so there seems to be a slow convergence.
<wpwrak>
the next step would then to integrate a power supply. these are of course already converging with multimeters ;-)
arielenter has quit [Quit: Leaving.]
nicksydney has quit [Quit: No Ping reply in 180 seconds.]
nicksydney has joined #qi-hardware
xiangfu has quit [Remote host closed the connection]
wej has joined #qi-hardware
nicksydney has quit [*.net *.split]
pcercuei has joined #qi-hardware
nicksydney has joined #qi-hardware
<whitequark>
DocScrutinizer05: ooooh I just had a much better idea about silkscreening
<whitequark>
see, my problem with stencils is that the ink really tends to disperse over much wider area than I want it to
<whitequark>
and I don't see any easy way to solve this, less of a rigid frame, some pressing mechanism and maybe that's not even enough
<whitequark>
the other problem is that my engraving bit is too huge and 125µm film appears to be too thick
<whitequark>
well, that can probably be solved with work, but this idea might prove to be much simpler
<whitequark>
so basically: apply dry film resist over mask. expose a negative image of silkscreen on it. use a spatula to spread ink
<whitequark>
acrylic is resistant to bases, hence I would be trivially able to remove resist with NaOH afterwards without damaging the imprint
<whitequark>
and film is 50µm thick → just about right amount of ink
<whitequark>
the only question left is whether NaOH would strip cured solder mask. I hope no, but lemme test it.
<whitequark>
also the transport company will deliver hypophosphite tomorrow \o/
<DocScrutinizer05>
I really never thought you could apply paint like solderpase to a stencil. Use air spray gun
<whitequark>
well, that's how silkscreening works! I thought I'd try to duplicate it
nicksydney has quit [Remote host closed the connection]
<whitequark>
thought about trying air spray, too, maybe I should
nicksydney has joined #qi-hardware
<whitequark>
anyway I want to try the resist idea
<whitequark>
it sounds just crazy enough to work
<whitequark>
essentially it would be exactly like silkscreening, except without the mesh
unclouded_ has quit [Ping timeout: 245 seconds]
<whitequark>
this vaguely reminds me of planar process :] how much of a resolution early ICs required, 200µm? I can do 100!
<DocScrutinizer05>
200um ? you might be right but it sounds like LOL
<whitequark>
well exactly. you could make these with a needle and a steady hand!
<whitequark>
DocScrutinizer05: no, but I like the way you think :3
dos1 has quit [Ping timeout: 244 seconds]
rz2k has joined #qi-hardware
nicksydney has quit [Remote host closed the connection]
nicksydney has joined #qi-hardware
<wpwrak>
DocScrutinizer05: spraying sounds like a good idea. and an airbrush is something fun to have anyway :)
<whitequark>
wpwrak: so you think I need to get an airbrush? or rather an aerosol can?
<DocScrutinizer05>
the latter is the lowcost limited-options variant
<wpwrak>
nicksydney: cute, but needs USB :)
<DocScrutinizer05>
though, I actually seen spray cans that had a screw-able lid and you would fill them with your paint, close, and pressurize with a second can of propellant
<wpwrak>
nicksydney: i'd rather see the pour their genius into making KL2 chips with more memory in QFN-32 packages
<wpwrak>
whitequark: airbrush has more control than a can. of course, it's a more money on the table to get going. also needs a bit of experimenting before you'll get it right. if you want just acrylic, about any airbrush setup will do. if you also want epoxy, you'll need a relatively powerful compressor (at least so i've been told - didn't try to feed mine with epoxy)
<whitequark>
wpwrak: wait, airbrushing epoxy? O_o
<wpwrak>
epoxy paint is much tougher (wear-resistant) than acrylic paint
<whitequark>
oooh epoxy paint, interesting
<wpwrak>
i think epoxy paint is what they use on fridges and such
<wpwrak>
not sure what's used on cars. maybe there, too
<whitequark>
$1000 for a mill built out of polyethylene, with 140mmx115mmx35mm working area
arielenter1 has quit [Quit: Leaving.]
arielenter has joined #qi-hardware
<roh>
yikes
<whitequark>
exactly
<whitequark>
and they promise .01mm repeat positioning accuracy, which is... just bullshit
<roh>
well.. maybe they do. but its a 'soft crud' only device anyhow.
<roh>
wax, simple pcb
<whitequark>
how would they do it with a LDPE frame?
<roh>
fr1 only
<whitequark>
wait, FR1 only?!
<roh>
its a toy. no clamps existing.
<roh>
they use some doublesided tape for everything they cut
<whitequark>
oooh fuck
<roh>
if you wanted a mill.. this isnt it. its nice for beginners in electronics and mechanics i guess... maybe for schools
<roh>
building simple led blinky things or so
<roh>
we want a pcb mill too.. but never wanted to invest the 1.5-2.5keuro minimum for a proper setup
<roh>
we -> our hackerspace
<roh>
we got a mill, but cam is hard... and its low-rpm only (3k max)
<whitequark>
nono, a guy I know bought it
<whitequark>
and I'm telling him it's crap
<roh>
also ordering pcb from china is too cheap. doublesided 5x5cm 10pcs 1.6mm with printing and solderstop for 10euro
<whitequark>
it very quickly rises up if you want bigger pcbs, I've considered that
<whitequark>
look higher at the chart
<whitequark>
also, 20 day lead time is... not something I want
<wpwrak>
whitequark: "nono" is his name or what you told him ? :)
<whitequark>
nono is my response to the roh's absurd thought that I wanted that mill
<wpwrak>
other ideas for silk screen: if you don't mind the color to be black, toner transfer. toner transfer may also be an alternative way to get a mask.
<whitequark>
I've already discussed toner transfer mask here. it's shit and doesn't really have any of the properties you'd want from a mask
<whitequark>
not scratch-resistant, not very solder-resistant, not pretty, etc
<whitequark>
toner transfer silkscreen could definitely work, if the black text is recognizable on the substrate
<whitequark>
it's not quite on a deep-green solder mask
<wpwrak>
true. toner certainly isn't shiny white ...
<wpwrak>
(toner mask) i mean as mask before applying the paint
<whitequark>
oh
<whitequark>
but how I'd remove toner afterwards? acrylic is damaged by acetone.
<wpwrak>
hmm, yes, finding a thinner that dissolves one but not the other may be tricky
<whitequark>
I have high hopes for aerosol
<wpwrak>
didn't you mention also getting paint you heat to cure ? the sort of stuff used on pottery ? that could work. mask, paint, heat, dissolve rest
<whitequark>
it doesn't involve pushing through stencil so it is highly likely to work
<whitequark>
wait, "rest" ?
<whitequark>
how'd I heat it selectively?
<wpwrak>
heat all
<wpwrak>
or get a laser engraver, yet another option :)
<wpwrak>
mount a joerg killer laser on your mill :)
<whitequark>
well, see, I bought that paint you heat
<whitequark>
but 1) it appears absolutely the same as the regular paint
<wpwrak>
ah. so acetone and friends remove it ?
<whitequark>
well, it's acrylic-based
<wpwrak>
another idea: if the paint is too thin, mix it with something. flour, talcum, etc.
<whitequark>
there's a paint thickener in that shop, but I think the core of issue is in another thing
<whitequark>
when you apply pressure to silk, it just flexes locally and still adjoins the board closely
<whitequark>
however this PET film is rather hard, so if you apply pressure to it and it flexes for some reason... it'll detach from board. meaning you push paint under film.
<wpwrak>
hmm, you could try to make it convex/concave. then it would itself maintain a pressure against the board. well, may need some experiments to figure out things
<wpwrak>
maybe you could also coat it with something rubberish, which would act as buffer and seal
<wpwrak>
of course, more experiments :)
<whitequark>
convex/concave would mean it won't adjoin the pcb on all surface...
<wpwrak>
well, you'd mount it such that the corners are tallest. so if you clamp them down, the whole thing should generate a downward force everywhere
<wpwrak>
but of course, too much curvature and you'll get waves ... or cracks
<whitequark>
then corners would be FUBAR though
<wpwrak>
make it bigger than the pcb
<whitequark>
hmmm, I don't think PET film flexes like that
<whitequark>
like, it wants to flex either horizontally or vertically
<wpwrak>
suspend it, on the corners, then gently apply hot air ?
<whitequark>
eugh
<wpwrak>
;-)
<whitequark>
that'll be really hard to do reliably without morphig those tiny .2mm features
<wpwrak>
it only has to flex, not melt :)
<whitequark>
naw, not a good idea.
<whitequark>
I'm more thinking along the way of a proper silkscreening frame, except to keep PET film in it
<whitequark>
think I could mill something like that
<wpwrak>
well, if you don't need very fine lines, spring-mount a pen that draws in white (like the stuff used for correcting) on your mill and just plot :)
<DocScrutinizer05>
LOL
<wpwrak>
or, more fancy, mount a small brush and let the mill tip it into your paint :)
* DocScrutinizer05
likes the part about 2joerg kiler laser"
* DocScrutinizer05
likes the part about "joerg killer laser"
dos11 has joined #qi-hardware
<DocScrutinizer05>
actually, have you considered inkjet printing?
<whitequark>
DocScrutinizer05: on what?
<DocScrutinizer05>
rather, with what
kristian1aul has joined #qi-hardware
<DocScrutinizer05>
piezo printheads might work just fine with some acrylic paints
arielenter1 has joined #qi-hardware
<DocScrutinizer05>
or maybe use black rubberfoam and a laser and build a stamp from that
<whitequark>
hmmm
<whitequark>
if I had a laser, I'd just cut proper .1mm features on stencil :p
<DocScrutinizer05>
or use a PCB and do copperplate print? ;-)
<DocScrutinizer05>
sound like a nice idea to me
<whitequark>
copperplate print?
<DocScrutinizer05>
you can even use extra thick copper
<wpwrak>
in argentina most things you buy locally are also 2x what you'd pay in the US. there are of course about 50% import taxes, sales tax (not sure if that can be deducted from the import taxes), shipping, customs processing fees, vendor's margin, ...
<wpwrak>
to .ru ?
<whitequark>
to anywhere
<whitequark>
they ship from HK
<whitequark>
taxes... well
valhalla has joined #qi-hardware
apelete has joined #qi-hardware
porchao has quit [Read error: Connection reset by peer]
porchao has joined #qi-hardware
viric has joined #qi-hardware
kristianpaul has joined #qi-hardware
kristian1aul has quit [Read error: Connection reset by peer]
apelete has quit [Ping timeout: 252 seconds]
arielenter1 has quit [Quit: Leaving.]
arielenter has joined #qi-hardware
apelete has joined #qi-hardware
arielenter has quit [Quit: Leaving.]
arielenter has joined #qi-hardware
<whitequark>
haha, their (othermachine) argument for FR-1 is "FR-4 is harmful when inhaled"
<DocScrutinizer05>
I bet that's correct, at least when you inhale a fullsize eurocard
<whitequark>
well, according to MSDS it is slightly irritating
<whitequark>
but recommending a fullblown carcinogen instead of a slightly irritating substance because your machine couldn't mill the latter is a whole new level of hypocrisy
<whitequark>
I would even say that is more than slightly irritating *rimshot*
arielenter has quit [Quit: Leaving.]
<DocScrutinizer05>
inhaling any object of eurocard size is more than slightly irritating
<DocScrutinizer05>
I dunno if it causes cancer though
<DocScrutinizer05>
probably you won't live long enough to develop cancer
<whitequark>
phenolformaldehyde resins tend to emit both of these components, afaik it was used extensively in furniture (PF-resin-bound wood)
<whitequark>
and that was bad enough those were banned *in Russia*
<DocScrutinizer05>
yup
<whitequark>
atleast I remember that fact from my childhood and I didn't have a whole lot of non-RU discussion around
<DocScrutinizer05>
formaldehyde is banned pretty much everywhere now
<whitequark>
ooh, right, *that's* why there are no sources for FR-1 except some shady alibaba guys
<DocScrutinizer05>
I still recall using shampoo which praised the formaldehyde content on boilerplate
<whitequark>
anti-lice?
<DocScrutinizer05>
no, regular shampoo
<whitequark>
I can't think of anything else warranting addition of formaldehyde
<DocScrutinizer05>
makes your hair stronger
<DocScrutinizer05>
or somesuch
<whitequark>
was there a toxic-chemical-craze, just like radiation-craze?
<DocScrutinizer05>
hm?
<whitequark>
well you know, in the beginning of 20th century there was a radiation craze. "drink radium salt 20 times a day and all illnesses will disappear", somesuch
arielenter has joined #qi-hardware
<wpwrak>
makes your hair stronger ... assuming that it kills you before your hair gets weak again
<wpwrak>
side effects: the cancer therapy may cause hair loss.
<DocScrutinizer05>
there also were inlays for shoes that had some substance that when getting wet produced formaldehyde, wearing this stuff in your shoes for two days allegedly cured stinkfoot
<DocScrutinizer05>
btw you know that methyl alcohol is poisonous because it metabolizes to formaldehyde?
<DocScrutinizer05>
just like ethanol metabolizes to acetaldehyde
<whitequark>
yeah
<whitequark>
and antidote is ethanol, 'cause it competes as an alcoholdehydrogenaze substrate
<whitequark>
leaving more time for your poor liver to process resulting formaldehyde
<whitequark>
even if that stuff wasn't discussed on my freshman year in uni, I *am* russian after all :p
<DocScrutinizer05>
that's why the standard therapy for methanol poisoning is drinking large amounts of alcolhol, so the liver can't metabolize so much methanol per time unit, reducing formadlehyde concentration in body
<DocScrutinizer05>
I see you been faster in typing
<wpwrak>
DocScrutinizer05: now that sounds nice. go to the hospital, tell them you drank some methanol, get booze all night on doctor's orders ;-)
<whitequark>
wpwrak: nope, never did
<DocScrutinizer05>
this happens every day
<whitequark>
wpwrak: (hospital) I'm sure they have a standard procedure for such cases, with sole purpose of making your life hell
rz2k has quit []
<whitequark>
e.g. perform a gastric lavage just for the sake of it
<DocScrutinizer05>
yes, they do
<DocScrutinizer05>
and you don't drink the alcohol but rather I.V.
<whitequark>
that gets you drunk more efficiently
<DocScrutinizer05>
yep
<wpwrak>
whitequark: i see that the spirit of Yezhov hasn't died yet :)
<DocScrutinizer05>
but no fun either
<whitequark>
a homemade version of that would be an alcohol enema, tampon or just go to bathhouse and pour vodka on hot stone, therefore absorbing it through lungs
<whitequark>
a positive aspect of it is that you get less hungover and don't smell of last night's liquor
<whitequark>
a negative aspect of it is that it's impossible to evacuate via puking, therefore if you overdose it's rather fatal
<whitequark>
and yes, we discussed all that in classes
<wpwrak>
very pragmatic :)
<whitequark>
I honestly don't even remember context anymore. we did discuss a lot of fun things though
<whitequark>
effect of meth and heroine on dopaminergic system (brutal)
<whitequark>
neurotoxins
<whitequark>
a *lot* of various neurotoxins and their biological activity
<DocScrutinizer05>
dopaminergic system?
<wpwrak>
in russia, you learn for life, not just for school ;-)
<whitequark>
DocScrutinizer05: reward/motivation system of the brain, composed of special neurons with receptors for dopamine
<DocScrutinizer05>
hmm, and what's the effect?
<whitequark>
taking drugs causes the neurons to die and brain's own dopamine output to diminish (homeostasis; if you have receptors stimulated externally, internal means of production will shut down)
<whitequark>
as a result it's more or less depression for the rest of your life
<DocScrutinizer05>
o.O cool¡
<whitequark>
it's a rather abridged version, of course, but I hope it conveys the gist of it
* wpwrak
imagines whitequark, after DocScrutinizer05's question, running down to the dealer at the next street corner, get some collection, toss some pills, run up, and describe the effect in scientific terms :)
<whitequark>
dissecting my own brain would be rather complex
<whitequark>
plus there's a *lot* of literature describing exactly what wpwrak wants to hear
<whitequark>
both scientific and amateur
<DocScrutinizer05>
yeah, worst thing in that regard been a liver resection
<wpwrak>
i'm sure the right drugs will give you enough introspection to manage that without even a skull drill :)
<whitequark>
oh? liver?
<DocScrutinizer05>
some med student, at home. Then halfway drove to hospital since he ran unto some trouble I don't recall anymore
<whitequark>
hardcore
<whitequark>
worst thing I heard about, a doctor on polar station performing appendectomy on himself, since no one else could
<wpwrak>
dies ... at the age of 110, in otherwise perfect health ?
<whitequark>
>Rogozov died in 2000, aged 66, in Saint Petersburg, Russia, from lung cancer.
<wpwrak>
hmm, should have quit the radon sooner
<whitequark>
smoking, more likely
<DocScrutinizer05>
polar
<DocScrutinizer05>
all the radiation there
<DocScrutinizer05>
(j/k)
<whitequark>
lung cancer. lungs aren't the most sensitive body part to radiation
* DocScrutinizer05
still wonders why the neurons would die
<whitequark>
ah, no, actually could be radiation
<whitequark>
50/50 lung/leukemia
<whitequark>
DocScrutinizer05: overstimulation
<DocScrutinizer05>
O.o
<whitequark>
you're right to be surprised, that's not how neurons normally work
<whitequark>
but dopaminergic ones are a bit special
pcercuei has quit [Quit: dodo]
<whitequark>
I don't quite remember all the details already
<whitequark>
lemme see if I still have the textbook
<DocScrutinizer05>
sounds a bit like the scientific version of "LSD causes cancer"
<whitequark>
nope I don't have it
<whitequark>
no, it's rather well-confirmed
<DocScrutinizer05>
I mean, shouldn't such severe side effects get mentioned in all opiate analgetica wash papers?
<whitequark>
hmm
<DocScrutinizer05>
I'm pretty sure about methamphetamine, it's proverbially turning your head into a swiss cheese
wej has quit [Ping timeout: 252 seconds]
<DocScrutinizer05>
but opiates and opioids are used in medicine since maybe 100 years now
<whitequark>
I may be confusing something, that lecture was in 2009
<DocScrutinizer05>
I seem to know L-dopa (used to treat parkinson?) causes further damage to CNS so eventually it doesn't work anymore
<whitequark>
hmm, that sounds wrong. L-dopa is a precursor to dopamine, it helps when your dopaminergic neurons degrade naturally
<whitequark>
but it doesn't really cure the underlying reason of that degradation (genetics in case of parkinson)
<whitequark>
oh, no, parkinson's cause is still unknown?
<whitequark>
wow
arielenter has quit [Quit: Leaving.]
<whitequark>
"The drawback of levodopa treatment is that it treats the symptoms of Parkinson's (low dopamine levels), rather than the cause (the death of dopaminergic neurons in the substantia nigra)."
<whitequark>
okay, I can't find sources for what I said above