#qi-hardware IRC log for Saturday, 2014-02-22

whitequarkDocScrutinizer05: http://hackaday.com/2014/02/21/meltinator-9000-fuses-glass-by-degrees/#comment-121495100:57
whitequarkDocScrutinizer05: I found an interesting thing locally, HP C6778A film01:55
whitequarkadvertised as "UV-resistant", hence it is probably *intended* for printing photonegatives01:55
whitequarkthough it costs $300 so I don't think I want it01:56
whitequarkby the way, it was indeed the concentration of resist05:01
whitequark15% etchant removes 35µm of copper in 20 minutes very cleanly05:02
whitequarkat 27°C05:02
DocScrutinizer05(( <whitequark> by the way, it was indeed the concentration of resist )) <-- ??05:55
whitequarklemme upload a note, there's fabulous pictures05:56
whitequarkwell, no, not yet, need to test with proper test pattern06:05
whitequarkthough: http://i.imgur.com/U4ItxjK.jpg06:05
whitequarkthat's what those crystals were. I identify as CuSO„·H‚O due to pale blue color06:06
DocScrutinizer05watching the glass with drop of Galden in it, it occurred to me to wonder whether inert substances have taste/smell. I tend to think they could06:13
whitequarkhm well, see, it's twofold06:14
whitequarkon one hand human nose can be pretty sensitive, detecting single ppm concentrations is routine06:14
whitequarkon other one *why* do you think you feel odors? because it conferred some advantage. hence, stuff you can eat, stuff that can infect you, and that's about it06:15
whitequarkthe only poisonous gases which have pungent odor are those you can find in nature06:15
whitequarkeg H‚S is awful yet CO is odorless06:15
DocScrutinizer05that's an interesting viewing angle06:15
whitequarkthat's no idle speculation, I've asked this question to my physiology teacher06:16
whitequarkso. it's more or less same with taste. and I have really big doubts about availability of galden in nature06:16
whitequarkanyway, just taste it? it's not toxic and doesn't cause sensitization06:16
whitequarkMSDS says so at least06:17
DocScrutinizer05I've a more theoretical approach: how does smelling work? I think it orks by pattern matching, not by chemical interactivity06:18
whitequarkthe neurons responsible for smell have receptor proteins on their surface, exposed to air06:18
whitequarkthose receptors are activated by either whole compounds or certain functional groups06:18
DocScrutinizer05good keyword06:19
DocScrutinizer05it gives a clue where to look for how it works06:19
whitequarkpubmed.com :)06:19
whitequarkwell, pubmed is good if you need something specific. for general inquiries it's better to pick up a physiology textbook06:19
whitequarklemme try to remember which one we used...06:19
DocScrutinizer05I know of a number of proteines that are supposed to work without chemical interaction to e.g. DNA06:20
DocScrutinizer05more like mere mechanical tools06:20
whitequarkum, I think you're confused here06:20
whitequark*all* interactions on that scale are wholly chemical, meaning electron shells of proteins and their substrates interact06:21
whitequarkif a protein seems to "pump" something without affecting its structure, it means that it creates a weak bond which is soon dissolved06:21
whitequarkfor example06:21
whitequarkwhat I mean is that you cannot disregard interaction of electron shells, it's crucial to the function, even if start and end conformation is the same06:23
DocScrutinizer05and are those hulls active on inert substance?06:24
whitequarkdefine "active"06:24
whitequarkthere's always electrostatic interaction, with one outcome or another06:24
DocScrutinizer05or could you say an inert substance (say gold, argon) is *always* free of taste and smell?06:24
whitequarkthere's no such thing as "absolutely inert", but for human purposes no proteins would interact with argon (and gold, I think) strongly enough to produce measurable signal06:25
whitequarkI really don't know how exactly "inert" galden is06:26
DocScrutinizer05I don't wonder about Galden06:29
whitequarkwhat about then?06:30
DocScrutinizer05I just wondered if those proteines *can* interact wih ibert stuff06:30
DocScrutinizer05I thought they can06:31
whitequarkwell... turns out gold isn't really that inert06:32
whitequarke.g. there are bacteria for which gold is toxic and they excrete it in nanoparticles: http://www.nature.com/news/gold-digging-bacterium-makes-precious-particles-1.1235206:32
whitequarksuch a tiny peptide used for accumulating the metal: http://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?sid=16065771506:33
whitequarklemme also check the inert gases, maybe there's something I don't know about that06:34
whitequark"At a pressure of 7 bar, four xenon binding sites were found in myoglobin"06:37
whitequarkXe, Kr and Ar were bound to an engineered T4 bacteriohpage06:37
whitequarkhowever as I understand, it's not living stuff, it's just in lab06:37
DocScrutinizer05so you say rare gas is ingerently free of any smell/taste?06:38
whitequarkno, it works in living stuff too; xenon can be used for anastheseia06:39
whitequarkDocScrutinizer05: it appears that proteins can indeed bind heavy noble gases like Xe, Kr, Ar06:39
whitequarkso it's not inherently, it's just because that feature would be useless06:39
DocScrutinizer05thought as much06:39
DocScrutinizer05yeah, many thanks for this very inspiring new viewing angle06:40
whitequarkheh, you're welcome06:41
wpwrakwhat's incidental, the ability to bind or the (lack of) smell/taste ?07:03
whitequarkwpwrak: the lack of smell/taste07:05
whitequarkaka, regardless of whether it's *possible* to have binding proteins, *will* we have them?07:06
whitequarkwill we need, rather07:06
wpwraki'd agree that the binding may be incidental (though there are cases where "exotic" atoms appear in this sort of places, doing something useful. so i wouldn't be too dismissive without some background research. oops, there goes another bunch of PhDs ...)07:09
wpwrakif the binding happens in real life and the chemistry produced no other results, then the taste should indeed be absent07:10
wpwrakif the binding doesn't happen outside labs, then the taste should be arbitrary07:10
whitequarkwpwrak: no no, this is not what I meant at all07:10
whitequarksee, the receptors are usually very specific. they simply won't bind to anything except their own compounds or groups07:11
whitequarksure, it sometimes happens that something binds somewhere completely unrelated, but it's kinda rare07:11
wpwrakarbitrary = e.g., possibly determined by analogous mechanisms, and thus following their analogous pattern, even if the chemical affect is not comparable07:12
wpwrakah, i see. so you mean that it's no coincidence07:12
wpwraki'd agree, as long as it's a reaction that can happen a reasonable amount of times in real life07:13
damo22anyone familiar with WZR buffalo device?07:27
damo22i have one here and tried flashing librewrt to it, im not sure what to do next because i cant seem to get a DHCP address from the router07:28
whitequarktry #librewrt maybe?07:30
Action: whitequark ponders if he should buy that lomond high-temp film tomorrow or wait for delivery on monday07:43
whitequarkhm, interesting. I tried to use F200 instead of F20 and got much cleaner cut for PCBs08:55
whitequarkno built-up copper edge08:56
whitequarkthough it seems... the dimensions are significantly different? weird08:59
whitequark11.4 on F200, 11.2 on F2008:59
whitequarkcutting a circle with d=11 with a d=1 endmill08:59
pcercueisounds like a Ferrari09:22
whitequarkg-code for "feedrate 200mm/min"09:29
DocScrutinizer05seems to me like that CNC program is utter crap, eh?09:33
DocScrutinizer05you said it09:34
DocScrutinizer05((<whitequark> though it seems... the dimensions are significantly different? weird))09:34
whitequarkI don't think it has something to do with CNC program09:34
whitequarkrather the shitty way I fix the PCB on table09:34
whitequarkdouble-sided adhesive tape09:34
DocScrutinizer05I can't come up with a story how that could get caused by sticky tape09:36
whitequarktool pushes workpiece around while moving09:36
whitequarktape is not rigid enough. it doesn't move very easily, but it can definitely move ±0.1mm09:36
DocScrutinizer05shouldn't the circly be *smaller* on F200 then?09:37
DocScrutinizer05oh well, maybe it's about time, not force09:37
whitequarkmaybe has something to do with cutter forces? climb vs conventional milling09:37
whitequarkaka the direction of cut vs direction of spin09:37
DocScrutinizer05you probably want to build a proper fixture, consisting of a 11mm MDF with some steel and screws09:39
whitequarkwell. I'm still a bit lost as to how fix a PCB I'm cutting from inside a bigger piece of PCB09:40
DocScrutinizer05now that's probably the easiest part? drill 4 holes, use 4 SPAX to fix PCB to MDF victim material09:41
whitequarkassuming I want 4 holes in that pcb, yes09:41
DocScrutinizer05well, otherwise you need to place the spax carefully and precisely to the edge of PCB, so the spax cyl head bottom will center the PCB and give it 100% rigid mounting09:43
DocScrutinizer05you'll need 8 spax for that, 2 on each side09:43
DocScrutinizer05or you use the steel stripes I suggested, 2mm thick and maybe 10*50mm, with two long holes for two screws to fix09:45
pcercueiany of you guys going to the embedded world conference in Nuremberg?10:06
Action: larsc ;)10:09
pcercueiI guessed so :p10:09
DocScrutinizer05not too far for me ;-)10:11
DocScrutinizer05random sidenote: UMTS dwonload of some random stuff. It initially had a terrible ditch in bandwidth, foing down to <100k/s every now and then -> http://privatepaste.com/a373622b4810:13
Action: whitequark has suddenly made this: https://pbs.twimg.com/media/BhE2maMCIAAH2A2.jpg:large11:43
whitequarkDocScrutinizer05: yeah!13:54
whitequarkbtw I just went to a Lomond shop, bought some film for hi-temp laser printers and chatted with the friendly guy there13:56
whitequarkwhat he told me:13:56
whitequark1) he isn't aware of any difference between regular and hi-temp film except thickness: 100µm vs 125µm13:56
whitequark2) film most certainly and definitely should not deform when ran through my DCP-7010R (which isn't hi-temp by the way) or via a 120°C laminator13:57
whitequark3) he has no idea why setting "Transparencies" screws the picture up, though he wasn't looking very puzzled either--I suspect printers sabotaging one's job are quite common13:58
wpwrakDocScrutinizer will leave his cave ? guys, take pictures ! that's more rare than sighting nessie or bigfoot together13:59
DocScrutinizer05 /o\13:59
whitequark4) he is aware of only two parameters printer would vary based on "paper type" box: fusor t° and paper advance speed13:59
whitequarkso... will go home and then test this out14:00
wpwrak#s/ or / and / # that's what you get for editing your sentence while still half asleep14:00
DocScrutinizer05wpwrak: I need that to get the drive running. You know, "heart of gold"14:02
whitequarkthe improbability engine?14:02
DocScrutinizer05infinite improbability drive14:02
whitequarkdon't tell me you run our universe in zaphod mode!14:03
DocScrutinizer05and it always seems like my encounters out there are exactly like described in those novels14:03
wpwrakpeople with two heads, talking fish, and such ...14:03
DocScrutinizer05ooh, I planned to have a short service session on my home automation14:05
DocScrutinizer05http://wstaw.org/m/2014/02/22/plasma-desktopwR3389.png nausea inducing, no?14:08
whitequarklooks like windows 9514:08
whitequarkthose comboboxes... ugh14:09
DocScrutinizer05while this doesn't help the nausea either: http://wstaw.org/m/2014/02/22/plasma-desktopBs3389.png14:14
DocScrutinizer05I mean, those are only 6 changing digits, how long can it take to copy this crap?14:16
DocScrutinizer05Total DISK READ:    1631.66 K/s | Total DISK WRITE:    1597.19 K/s14:18
DocScrutinizer05  TID  PRIO  USER    DISK READ>  DISK WRITE  SWAPIN      IO    COMMAND                                                                                                                        14:18
DocScrutinizer0517772 be/4 root        163.01 G    162.17 G  0.00 % 92.73 % cp -av /home/jr home-jr/14:18
-:#qi-hardware- [freenode-info] channel trolls and no channel staff around to help? please check with freenode support: http://freenode.net/faq.shtml#gettinghelp14:32
DocScrutinizer05ooh, real netsplit14:32
DocScrutinizer05freenode suffering netsplits from DDoS15:56
larscprobably the GCHQ in their fight against anonnymous16:01
whitequarkanother fun thing, it still gets deformed by printer rollers BUT that does not affect the print quality at all, it is perfect at all times16:06
whitequarkwell, and deformation are barely noticeable too (but present)16:06
whitequarkalso passes the "grid test"16:19
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