2013-12-25 00:01 arielenter has quit [Ping timeout: 260 seconds] 2013-12-25 00:08 dos1 has quit [Ping timeout: 272 seconds] 2013-12-25 00:36 arielenter has joined #qi-hardware 2013-12-25 00:40 pcercuei has quit [Quit: Lost terminal] 2013-12-25 00:55 arielenter has quit [Quit: Leaving.] 2013-12-25 03:16 unclouded has quit [Ping timeout: 246 seconds] 2013-12-25 04:52 roh, wpwrak_: what do you think of this CNC machine? http://www.mydiycnc.com/the%20design 2013-12-25 05:22 or this one: http://www.ebay.com/itm/CNC-3020T-DESKTOP-ROUTER-ENGRAVER-ENGRAVING-DRILLING-MILLING-MACHINE-NEW-p8-/200721798773 2013-12-25 08:16 panda|w530 has joined #qi-hardware 2013-12-25 09:03 wolfspra1l has joined #qi-hardware 2013-12-25 09:06 wolfspraul has quit [Ping timeout: 248 seconds] 2013-12-25 11:06 pcercuei has joined #qi-hardware 2013-12-25 11:11 rz2k has joined #qi-hardware 2013-12-25 11:17 dandon has quit [Ping timeout: 256 seconds] 2013-12-25 11:23 dandon has joined #qi-hardware 2013-12-25 11:34 wej has quit [Read error: Connection reset by peer] 2013-12-25 11:37 wej has joined #qi-hardware 2013-12-25 11:51 dos1 has joined #qi-hardware 2013-12-25 12:05 lekernel has joined #qi-hardware 2013-12-25 12:20 michael_lee has joined #qi-hardware 2013-12-25 12:43 fire has joined #qi-hardware 2013-12-25 12:48 >>Shipping: $399.00<< WTF? 2013-12-25 12:49 DocScrutinizer05: doesn't matter, there are others selling the same machine with sane shipping price 2013-12-25 12:55 0.05mm precision sounds good, if that's true 2013-12-25 12:56 particularly spindle motor axial often is a problem 2013-12-25 12:57 when the mill axis has 0.1mm room to move up when under pressure and come down again while slowly milling too deep into the workpiece, you got a pretty nasty problem 2013-12-25 12:58 you *might* be able to cure this by simply rotating the whole contraption upside down 2013-12-25 12:59 but obviously you mustn't have slackness in any other of the parts then 2013-12-25 12:59 well, in any of the parts that get pushed up by mill engaging to the workpiece 2013-12-25 13:01 the pricetag for that thing sounds reasonable, when it's not a flimsy scam 2013-12-25 13:01 however please ask roh who seems to have some RL experience with those sorts of machines 2013-12-25 13:02 DocScrutinizer05: I've seen several people on the net who bought this machine 2013-12-25 13:02 the general consensus seems to be that its mechanics are up to the task 2013-12-25 13:03 maybe a good idea to check by google what they are doing, and then asking them what they think about it 2013-12-25 13:03 no need, the guy already described it in the blog: http://makerflux.com/projects/my-new-cnc-router 2013-12-25 13:04 for an artist interested in milling tiny angel figurines from wood, the machine may be perfect while still completely unsuited for e.g. PCB milling 2013-12-25 13:04 http://makerflux.com/wp-content/uploads/2012/10/dscn61192.jpg 2013-12-25 13:05 (not saying it actually _is_ not suited for PCB) 2013-12-25 13:05 main two complaints seem to be shitty wiring (I can cope with that), and the fact it requires a hardware parallel port 2013-12-25 13:05 I don't know the machine 2013-12-25 13:05 (the controller is *incredibly* dumb) 2013-12-25 13:05 no problem either :-P 2013-12-25 13:05 yup 2013-12-25 13:06 either buy an old PC or use a micro to reimplement half of the control logic 2013-12-25 13:06 actually that's better than the controller being incredibly fubar 2013-12-25 13:06 huh? use a usb-parallel adapter 2013-12-25 13:06 I suspect the controller is done entirely of 74HC series or something like that 2013-12-25 13:06 DocScrutinizer05: doesn't cut it. timings are off 2013-12-25 13:06 ummm 2013-12-25 13:07 with HW LPT port it even requires Linux RT, the regular one won't work 2013-12-25 13:07 errrr- ummmm 2013-12-25 13:07 prolly a job for a beagleboard or sth like that then 2013-12-25 13:07 an atmega would suffice :p 2013-12-25 13:08 yeah 2013-12-25 13:08 but, yes. 2013-12-25 13:08 it's not a problem for me either 2013-12-25 13:08 or simply abuse an old injet printer's control logic ;-P 2013-12-25 13:08 inkjet* 2013-12-25 13:09 that actually sounds much more complicated 2013-12-25 13:09 yeah, it is 2013-12-25 13:09 but it shows what grunt in MCU you need 2013-12-25 13:10 I can't think how a USB is too slow 2013-12-25 13:10 I think it's more the fact that it doesn't have guaranteed latency that's a problem 2013-12-25 13:10 well, not with interrupt transfer, which USB-LPT adapters use 2013-12-25 13:11 btw: 2013-12-25 13:11 "You also need to be aware that there are not limit switches, and the system is open loop in design. The spindle speed control is manual, which is not too bad for a tool this small." 2013-12-25 13:11 even when you control the steppers PWM by bitbanging the parallel port's IOs, it still should easily do the maybe 5kHz with a precision of 8bit timing 2013-12-25 13:11 I'm not sure how bad is that 2013-12-25 13:11 aka phase modulation 2013-12-25 13:12 and requirement for RT-linux is basically nonsense. The developer just never heard of kernel drivers 2013-12-25 13:12 and high precision timers 2013-12-25 13:13 and IRQ 2013-12-25 13:13 it uses linuxcnc, not its own software 2013-12-25 13:13 yeah, and that got developed by a noob I guess 2013-12-25 13:14 of course you can't implement a PWM phase controlled stepper controller as a userland process 2013-12-25 13:17 but honestly, 480Mb/s USB2.0 speed should suffice to control a USB<->parallel converter pretty tightly 2013-12-25 13:17 that's really more about latency than bandwidth 2013-12-25 13:18 latency is a function of bandwidth 2013-12-25 13:18 and actually latency here is irrelevant unless this whole concept depends on meaningless IRQ events generated by the CNC-controller 2013-12-25 13:19 seems like it uses one input pin 2013-12-25 13:19 http://www.svxlink.net/wp-content/uploads/2012/01/Screenshot-EMC2-Stepper-Mill-Configuration-2.png 2013-12-25 13:19 you could introduce a delay in propagation of control signals from PC to parallel port, in the range of hours or days, and nothing would change 2013-12-25 13:19 ah, that's just the big stop button. so... no idea why it needs realtime 2013-12-25 13:21 more reviews: http://www.mycockpit.org/forums/showthread.php?t=21625&s=eb6502d9f23c55f0468a93d9c1a9e425&p=112943&viewfull=1#post112943 2013-12-25 13:21 and the latency in USB seems like 1s * (2*8bit) / 480E6bit/s 2013-12-25 13:22 okay, okay, I don't know 2013-12-25 13:22 which is still pretty sufficinetly short in my book 2013-12-25 13:22 I've seen someone write that it doesn't work with USB-LPT 2013-12-25 13:22 maybe it's hands.drv 2013-12-25 13:23 sure it doesn't work with USB-LPT since the whole program is a userland program that not even has access to direct USB 2013-12-25 13:23 the critter seems good enough for the cost overall... so waiting for what roh says 2013-12-25 13:23 it's amazing the whole thing works at all - even with using RT-linux 2013-12-25 13:24 you regularly want to implemet the complete bitbanging on a kernel driver level 2013-12-25 13:24 and that driver of course won't use libusb ;-P 2013-12-25 13:25 it however easily can use USB OHCI directly 2013-12-25 13:25 EHCI whatever 2013-12-25 13:25 ... I don't think so 2013-12-25 13:26 EHCI is nontrivial to use 2013-12-25 13:26 and why would you want to reimplement it anyway 2013-12-25 13:26 I nevertheless think the whole software is written in c# and no idea about kernel level drivers 2013-12-25 13:27 thus they reverted to RT-linux and cranked up the scheduling for the process so it never gets preempted 2013-12-25 13:27 and probably do direct bitbanging to the parallel port 2013-12-25 13:27 from userland 2013-12-25 13:28 I'll just make sure that the first board I do with it would drive it from USB 2013-12-25 13:28 and that will end the question :p 2013-12-25 13:28 hehe 2013-12-25 13:29 then I'd want to replicate atusb/atbens reliably, that would be a good test of the machine 2013-12-25 13:29 * DocScrutinizer05 just idly wonders how they made libmomo behave under RT-linux 2013-12-25 13:30 unrelated: I also bought a roll of this: http://www.ebay.com/itm/Dry-Film-Solder-Mask-Roll-of-12-in-x-42-5-in-bigger-lenght-by-request-/161140135802?pt=LH_DefaultDomain_0&hash=item2584b3577a 2013-12-25 13:30 wonder how well it will work 2013-12-25 13:32 OT: Cree has really awesome LED products 2013-12-25 13:32 as well as several types of photoresist... I just want to go and properly test and document all the convenient (absolutely no screwing with toner) ways of making PCBs I know 2013-12-25 13:32 and figure out which ones work best 2013-12-25 13:32 a white HighVoltage LED with Ufwd=23V 2013-12-25 13:32 huh, 23V 2013-12-25 13:32 yeah! :-D 2013-12-25 13:32 do they have several junctions on the same crystal? 2013-12-25 13:32 or what? 2013-12-25 13:32 a 10W 5*5mm LED 2013-12-25 13:33 don't ask me how they do it, they say SC^3[TM] technology 2013-12-25 13:34 I found a few really nice things at cree.com 2013-12-25 13:34 the 10W LED is ~5EUR at digikey 2013-12-25 13:34 oops nope 2013-12-25 13:35 http://www.digikey.de/product-detail/en/XMLBWT-02-0000-000LT20E8/XMLBWT-02-0000-000LT20E8CT-ND/3770904 2013-12-25 13:35 talking about LEDs: I want to use this http://www.ebay.com/itm/231121837688?ssPageName=STRK:MEBIDX:IT&_trksid=p3984.m1426.l2649 for exposing the resist/mask 2013-12-25 13:36 seems I could make it distributed (spatially) better than with lamps 2013-12-25 13:36 more even 2013-12-25 13:37 that strip eats 24W, at 30% efficiency it's 8W of UV... more than enough for quick exposure 2013-12-25 13:45 pcercuei has quit [Quit: leaving] 2013-12-25 14:09 my comment? generally you prefer a small concentrated light source for contact exposures of any kind 2013-12-25 14:10 ideally you'd have uniform parallel beams of light, from a light source infinitely far away 2013-12-25 14:11 the next best thing is a huge uniformly shining surface that has no minima and maxima 2013-12-25 14:12 so you achieve uniform exposure across the complete PCB even when the distance between light source and PCB is relatively short, like in the sub-meter range 2013-12-25 14:14 DocScrutinizer05: well, my thoughts were that 300 leds evenly distributed over surface is better than 2-4 lamps 2013-12-25 14:14 I'd dare to give a rule of thumb which is: the distance between light source and exposed object needs to be 10 times plus the size of the largest structure found in the lightsource itself 2013-12-25 14:15 so when your LED's are spaced at 1 inch, you should move away the lamp at least 10 inch from the PCB 2013-12-25 14:16 makes sense 2013-12-25 14:17 and of course your area of observation in the lamp is at least large enough so a point at edge of PCB "sees" the same when looking up, like a point in center of PCB 2013-12-25 14:17 means your lamp area has to be significantly *larger* than the PCB 2013-12-25 14:18 yes, that was my issue with my previous lamp. it was pretty tiny, about 15cmx4cm 2013-12-25 14:18 maybe 20cm 2013-12-25 14:18 or much much smaller ;-) 2013-12-25 14:18 mhm 2013-12-25 14:20 anyway, the size of the complete lamp also counts when checking for "largest structure seen inside the light source" 2013-12-25 14:20 unless the lamp#s size is way larger than the PCB 2013-12-25 14:21 it's all about unifirm exposure aka brightness the lamp creates on PCB surface 2013-12-25 14:21 and human eye is a pretty poor probing tool here, it doesn't notice */ 2 2013-12-25 14:22 photo resistive damn sure does 2013-12-25 14:22 I wonder if I could verify it with the photoresist itself 2013-12-25 14:22 like, expose it for five seconds, then develop... will it shed uniformly or not 2013-12-25 14:22 probably 2013-12-25 14:22 yes 2013-12-25 14:22 sounds feasible 2013-12-25 14:23 I'm just thinking of 4 mirrors forming an endless mirroring of original lamp 2013-12-25 14:24 that sounds weird 2013-12-25 14:24 but they need to be pretty good 2013-12-25 14:24 nah, that's not weird, that's simply a 4 walls enclosing the PCB and lamp setup 2013-12-25 14:26 so close to the lamp area from each of the 4 sides that when looking up to the lamp the PCB 'sees' and enless uniform area of one true and multiple mirrored lamps in all directions 2013-12-25 14:26 ideally gapless 2013-12-25 14:27 thanks, I'll consider this 2013-12-25 14:28 get 4 mirrors 30*80cm, build a square tube from them. then place your LEDs evenly spaced all over the one open end of the tube. Place your PCB into center of the plane of the other open end 2013-12-25 14:28 sounds complex but actually is pretty trivial 2013-12-25 14:29 yeah I got it 2013-12-25 14:29 except for the mirrors themselves which need to reflect UV light 2013-12-25 14:29 usual mirrors don't 2013-12-25 14:29 metal foil? 2013-12-25 14:29 yup 2013-12-25 14:29 eg thin Al foil 2013-12-25 14:29 alu foild maybe 2013-12-25 14:29 over say plexiglas 2013-12-25 14:30 :nod: 2013-12-25 14:30 afaik plexiglas is UV-transparent 2013-12-25 14:30 atleast it very much seemed to be transparent to me, seeing as the resist got exposed through it 2013-12-25 14:30 why not expose the alu foil directly 2013-12-25 14:30 it's not mechanically stable 2013-12-25 14:31 place it on top of some stable surface, like plexi or wood or steel 2013-12-25 14:31 use sticky or glue to fix it 2013-12-25 14:31 ah, right, I could just flip the plexiglas base 2013-12-25 14:31 so the foil would reflect UV directly 2013-12-25 14:31 yep 2013-12-25 14:32 as a bonus point it will shield whatever else there is in my room from UV 2013-12-25 14:32 yep 2013-12-25 14:32 pretty convenient exposure chamber 2013-12-25 14:33 not sure how much degradation would there be from occasional firing of ~10W lamp, but still 2013-12-25 14:33 right 2013-12-25 14:33 s/chamber\tower 2013-12-25 14:33 ;-) 2013-12-25 14:35 you could place a small hole on top between all the UV LEDs to peep inside, and a few red or maybe yellow LEDs for convenient illumination for human inspection 2013-12-25 14:36 and when you anna go fancy, you can even have a small string pulling up a mask that covers the PCB and protects it from any ambient UV while handling 2013-12-25 14:36 wanna* 2013-12-25 14:37 ooh, nope, as that would pretty much spil the mirror cabinet#s properties 2013-12-25 14:37 spoil* 2013-12-25 14:38 you could use a black plastic foil sheet to cover the PCB, and you pull up and out of the tower this whole plastic sheet with a string, through a hole (same hole used for peeping) 2013-12-25 14:39 sheet like "cloth" 2013-12-25 14:39 easily pull it out through a tiny hole 2013-12-25 14:39 since it folds up and slips through the hole 2013-12-25 14:44 it's always interesting what the body craves after a night of drinking. today, not just water but sugared water 2013-12-25 14:47 then for 'calibrating' you prepare a mask that has ... "40" "20" "10" "5" ..., place it in your chamber and cover it by a black sheet that comes out under the morror so you can pull it away step by step. Then you pull the cover until 40 is seen and uncovered and expose for 40s, then pull cover wurther until 20 is seen and expose for 20s. Then develop and see which number looks best. Let's ay it's the "10" then your optimum exposure 2013-12-25 14:47 time is 10+5+2+1 2013-12-25 14:49 when your numbers been like 1 2 5 10 20 50 100 200 500 2013-12-25 14:52 or you use 1 2 4 8 16 32, and expose "1" for one second, and everything N >1 for N/2 seconds 2013-12-25 14:52 whitequark: (cnc mill) looks nice. having the table split is a little unfriendly but the rest looks good 2013-12-25 14:54 that was about the second one. details are little hard to see for the first one 2013-12-25 15:04 DocScrutinizer05: USB imposes its frame timing. it's completely unsuitable for this type of basically GPIO control 2013-12-25 15:06 lekernel has quit [Ping timeout: 272 seconds] 2013-12-25 15:15 (10 W LED) it seems to be more like 2 W for continuous use, 2.9 V * 700 mA. the 3 A seem to be just pulse current. e.g., for a camera flash 2013-12-25 15:18 wpwrak_: I think that statement is a tad too oversimplified 2013-12-25 15:19 re USB 2013-12-25 15:19 it would largely depend on timing of that frames 2013-12-25 15:20 lekernel has joined #qi-hardware 2013-12-25 15:21 given those USB2parallel coverters easily handle GDI printers which often are no less stupid regarding in-device embedded intelligence and the amount of timing the host PC is supposed to provide for driving the GDI printer... 2013-12-25 15:21 (10W) nope, 3A/10W is coninuous operation 2013-12-25 15:22 700mA is just the test current 2013-12-25 15:22 for which color, efficientcy, forward voltage etc is rated 2013-12-25 15:23 you however need to take care about proper heatsink 2013-12-25 15:24 and I'm a tad lost there since I wonder how much of the power you feed to the LED is converted to light and which fraction actually dissipated for heating up the chip 2013-12-25 15:25 pcercuei has joined #qi-hardware 2013-12-25 15:25 (usb) frame timing is 1 ms at least up to full-speed. they have slightly finer granularity at higher speeds but i don't know how much finer. maybe 4x or so on high-speed. 2013-12-25 15:27 so this means that, e.g., if you do something like read a register (not the case in a cnc mill, but just to give an example), it takes 1-2 ms: 0-1 ms to send the read command and 1 ms to get the result. 2013-12-25 15:28 on highspeed that should be faster 2013-12-25 15:29 yes, it's faster because you have, i think they're called microframes 2013-12-25 15:30 the whole communication probably can be done streaming data words to the USB->parallel latch 2013-12-25 15:31 and even when not, 4k/s new values appearing on parallel output seem fine grained enough a timimg to drive a stepper motor, even by PWM 2013-12-25 15:33 (microframe) it's even 8x, so 8 kHz 2013-12-25 15:34 I think for driving stepper motors you need Ft of some 100Hz 2013-12-25 15:35 so we have a headroom of at least factor 20 here 2013-12-25 15:35 for multiplexing 3 motors via one 8bit (10bit) parallel 2013-12-25 15:35 lemme calculate ... 2500 mm/min, hmm, doesn't say what resolution. let's assume 0.05 / 16 2013-12-25 15:36 that would be 13.3 kHz. that may be close enough 2013-12-25 15:37 where from you take that factor 16? for PWM? 2013-12-25 15:37 not sure if pulse timing also matters, though. it might. e.g., it's not just stop and go but you try to accelerate the motor gradually. so you'd vary the frequency. 2013-12-25 15:38 from "16 subdivided driving down" 2013-12-25 15:38 that's however on a *completely* different scale 2013-12-25 15:38 and knowing that for example my mill has a 62 um resolution. 2013-12-25 15:40 we're talking about that CNC3020 though, and that has precision of 0.05mm 2013-12-25 15:40 I guess precision >= resolution here 2013-12-25 15:46 yeah, could be. 30 um would be 500 um/16 2013-12-25 15:46 err, sorry, confused :) 2013-12-25 15:47 http://www.youtube.com/watch?v=na9-USi_hZQ 2013-12-25 15:47 awesome 2013-12-25 15:47 50 um repeat, 30 um resolution. okay. surprisingly close 2013-12-25 15:48 wpwrak_: btw your calculation missing a tiny detail: for full speed moving you don't to fraktions of a step on a stepper motor 2013-12-25 15:48 you operate the motor at full steps at maximum operation frequency 2013-12-25 15:49 you do fracion steps only for smooth *slow* movements or for positioning netween two steps 2013-12-25 15:49 so your factor 16 isn't relevant here 2013-12-25 15:50 and that makes my statement about factor 20 headroom look pretty good, eh? 2013-12-25 15:50 want: http://www.youtube.com/watch?v=xZOiNdkJ8SU 2013-12-25 15:53 dear china, please make a USD 500 mill like that ;-) 2013-12-25 15:57 (steps) yeah, not sure how that fractional steps vs. full steps thing works 2013-12-25 16:00 phew. 36 C. getting a little hot today ... 2013-12-25 16:01 may be the hottest day the second half of this year 2013-12-25 16:09 michael_lee has quit [Quit: Ex-Chat] 2013-12-25 16:10 the fractional step thing works by giving (e.g.) 20% of current to phase-1 and 80% to phase-2, so the axis magnet positions on 1/5 of the angle between that phase-1 and phase-2 position 2013-12-25 16:14 the sequence is kinda like: 1; 1&2; 2; 2&-1; -1; -1&-2; -2; -2&1; 1... 2013-12-25 16:16 you can position between any of those 8 full steps by applying fractions of 100% current to either of both phases 2013-12-25 16:16 aka coils 2013-12-25 16:16 aka electromagnets 2013-12-25 16:17 oh, even analog regulation. fancy. 2013-12-25 16:17 PWM usually, yeah 2013-12-25 16:20 obvously you usually got a multiple of 8 steps per 360° rotation on most stepper motors 2013-12-25 16:20 up to 360 or more 2013-12-25 16:23 for full speed you often even skip intermediate steps and do "full step" 1, 2, -1, -2, 1... 2013-12-25 16:23 while the 8 step mode is calling the additional 4 steps half steps iirc 2013-12-25 16:24 sorry it's like 10 years since I last looked into that stuff 2013-12-25 16:27 hmm, the control box specs say "G Code" -> http://en.wikipedia.org/wiki/G-code 2013-12-25 16:30 this however might mean the software "API" on the windows computer 2013-12-25 16:33 hehe, yeah. i think they also mention mach on the windows side 2013-12-25 16:34 AWESOME! http://www.jinlantrade.com/ebay/3020t/CNCusermanual.doc 2013-12-25 16:34 apelete_ has joined #qi-hardware 2013-12-25 16:35 apelete has quit [Ping timeout: 245 seconds] 2013-12-25 16:38 >>After installing the Mach 3, on the desktop, there will occur 3 icon as follows: XXXXXX Notice: do not open them, please restart your PC at first (if you open the software not restart PC,it need uninstall fully and reinstall it) << 2013-12-25 16:39 LOL 2013-12-25 16:42 see "Engine Configuration... Prts & Pins" 2013-12-25 16:44 >>Kernel: 25000Hz<< 2013-12-25 16:46 according to 2nd window "Ports & Pins" Mach3 doesn't do half steps, and particularly no step fractions 2013-12-25 16:47 looks like lowest level interface for a pretty standards hardware stepper controller: direction and step signal 2013-12-25 16:48 so the controller box of the 3020 has 3 stepper controller chips I'd guess 2013-12-25 16:50 via USB according to what you wrote, we can make the motor do 8k steps per second 2013-12-25 16:52 and that's it. the only problem with this limitation is that stepper motor can't go faster than that, and the 'noise' that's particularly relevant when moving two axis concurrently is determined by the jitter in that 8k timeframe 2013-12-25 16:52 I can't see the motors mechanically following any such jitter 2013-12-25 16:53 axis magnet's inertia is a pretty good lowpass filter 2013-12-25 16:54 which also means the timing of the controller must not jitter so much that motor skips a step 2013-12-25 16:55 all this can get handled by simply not moving the motors at maximum speed 2013-12-25 16:56 I don't see any basic showstoppers for a USB<->parallel converter 2013-12-25 16:57 I think on windows some of those (rather their drivers) can even fake a IO port number that the driver is listening to, to emulate a built-in parallel interface 2013-12-25 17:01 rz2k has quit [] 2013-12-25 17:01 most of usb<->parallel converters (especially the cheaper ones) won't work - usually they're just emulating the printer interface 2013-12-25 17:05 http://www-user.tu-chemnitz.de/~heha/bastelecke/Rund%20um%20den%20PC/USB2LPT/index.en.htm 2013-12-25 17:05 :nod: 2013-12-25 17:06 I also just thought the Mach3 *might* use a definiton of doing fractional steps by applying PWM to the direction signal 2013-12-25 17:07 I never heard of sth like that in hw controller chips, but it would be pretty obvious a way to implement fractional steps 2013-12-25 17:09 hmm http://www-user.tu-chemnitz.de/~heha/bastelecke/Rund%20um%20den%20PC/USB2LPT/faq.en.htm 2013-12-25 17:09 Q9 is interesting 2013-12-25 17:14 ooh, "microstepping" not "fractional stepping" 2013-12-25 17:26 dos1: *excellent* find! :-) 2013-12-25 17:31 reading backlog 2013-12-25 17:33 wpwrak_: (good one) you mean the one from ebay? 2013-12-25 17:34 DocScrutinizer05: (1-2-5-10) yeah, figured, that's how I did it in the past 2013-12-25 17:34 (heatsink) for a self-adhesive LED strip with three hundred LEDs? how on earth are you suggesting to do that? 2013-12-25 17:36 wpwrak_, DocScrutinizer05: (pulse control) from the screenshots it seems that it has one Step and one Direction pin per axis 2013-12-25 17:36 yes 2013-12-25 17:36 oh, you found that already 2013-12-25 17:36 see http://www-user.tu-chemnitz.de/~heha/bastelecke/Rund um den PC/USB2LPT/ for a adapter that might "just work2 for you 2013-12-25 17:37 * DocScrutinizer05 hates it when fools add spaces to URLs 2013-12-25 17:38 * whitequark is looking at http://www-user.tu-chemnitz.de/~heha/bastelecke/Rund%20um%20den%20PC/USB2LPT/ul-17.en.htm 2013-12-25 17:38 I think I can manage to assemble that myself, even 2013-12-25 17:39 do they have any in stock? doesn't look like there's been made a lot of them 2013-12-25 17:42 ok, doesn't seem that anyone sells complete devices at all 2013-12-25 17:47 DocScrutinizer05: I was looking for some usb<->lpt converter while working on that drawing robot - finally gave up and used some old laptop with integrated lpt to control it :D 2013-12-25 17:47 and the chip is EOL 2013-12-25 17:47 not stocked even 2013-12-25 17:47 whitequark: it's a DIY thing 2013-12-25 17:47 rz2k has joined #qi-hardware 2013-12-25 17:47 dos1: wow, a laptop with LPT. I don't think I've ever seen one 2013-12-25 17:47 DocScrutinizer05: figured 2013-12-25 17:48 whitequark: http://www.tholt.com/images/toshtop.jpg something like that 2013-12-25 17:48 maybe even same model, looks similar 2013-12-25 17:49 dos1: that's a murder weapon, not a laptop :] 2013-12-25 17:49 hehe :D 2013-12-25 17:49 http://www.ebay.com/sch/i.html?_nkw=panasonic+toughbook+cf-27&_sacat=175672&_from=R40 2013-12-25 17:50 dang, seems we think alike, eh? 2013-12-25 17:50 didn't notice >>[2013-12-25 18:48:46] whitequark: http://www.tholt.com/images/toshtop.jpg something like that<< 2013-12-25 17:50 since I been searching ebay ;-) 2013-12-25 17:51 oh, there's a replacement for that EOL'd cypress chip 2013-12-25 17:51 and whitequark, *my* link is a murder weapon 2013-12-25 17:52 DocScrutinizer05: sure sure. *writes down to never ever screw with joerg* 2013-12-25 17:52 yeah, particularly since I have the somewhat even heavier CF-29 2013-12-25 17:54 http://www.ebay.com/itm/BLACK-TOUGHBOOK-CF-29-TOUCHSCREEN-Panasonic-laptop-Military-Police-RCMP-SWAT-/181286146497?pt=Laptops_Nov05&hash=item2a357f11c1 LOL 2013-12-25 17:55 lol @ part of the URL 2013-12-25 17:55 though... WTF is RCMP? 2013-12-25 17:55 http://www.youtube.com/watch?v=0n6mX8Q1waA 2013-12-25 17:56 56K modem... 2013-12-25 17:59 hehe, yeah, a funny relic in CF-29 2013-12-25 18:03 dos1: yeah, quite impressive. I also seen videos of divers operating CF-29 under water :-) 2013-12-25 18:03 though I don't recommend doing that "at home", the seals pretty often are _not_ 100% water tight 2013-12-25 18:05 anyway I guess when you get that 3020 CNC, you should get a dedicated PC for it right away, and better get one with parallel interface 2013-12-25 18:06 shouldn't cost you more than max 15% on top of the price for the CNC 2013-12-25 18:06 "when" already :p 2013-12-25 18:06 15%? pretty sure I can find one for free 2013-12-25 18:07 there's *tons* of old hardware lying around 2013-12-25 18:07 yep 2013-12-25 18:08 I really like that 3020 thing, for that pricetag 2013-12-25 18:09 almost temped to get one for me 2013-12-25 18:09 huh! guess that's a good thing 2013-12-25 18:10 * whitequark opens local ebay clone and sorts by price, asc 2013-12-25 18:10 swapping/adding the mill motor for/with a "printer" would make for a nice combined 3D-printer&mill, for really nifty hybrid stuff to build 2013-12-25 18:10 "pentium 100mhz, will give away for a liter of juice" 2013-12-25 18:10 DocScrutinizer05: hm, that is a very interesting idea 2013-12-25 18:13 duh! using a fibreoptic and focusing lens I guess you could do UV-curing for 3D printing *inside* a resin bath 2013-12-25 18:14 can you even send resin by mail? 2013-12-25 18:14 I doubt I can buy it here 2013-12-25 18:15 I have no clue which type of resin or other chemical would be used for conventional 3D light-curing printing 2013-12-25 18:16 apparently bisphenol-A based epoxy. eww. 2013-12-25 18:16 I'm not sure I want to touch that at all 2013-12-25 18:16 you are not supposed to _eat_ it :-D 2013-12-25 18:17 oh, it's not nearly as bad as pure phenol. okay then 2013-12-25 18:17 still... I don't need a 55-gal drum of stuff 2013-12-25 18:17 haha 2013-12-25 18:18 I wonder if you could do useful printing with a modified hotglue gun as print head 2013-12-25 18:19 could result in quite unique elasic objects 2013-12-25 18:19 I'm not sure they fit my definition of "useful" 2013-12-25 18:19 although they are sure unique. unique in their complete lack of applications? 2013-12-25 18:19 well, there might be *some* applications 2013-12-25 18:20 when usually you'd use silicon-rubber 2013-12-25 18:20 e.g protective sleeves 2013-12-25 18:20 yeah you can't really buy uv-curing resin here. it's either super-expensive specific stuff (special glues, dental, etc) or gigantic amounts from china or wherever 2013-12-25 18:21 contact the fabber scene 2013-12-25 18:21 arielenter has joined #qi-hardware 2013-12-25 18:21 they must have such stuff around 2013-12-25 18:21 fabber 2013-12-25 18:21 ? 2013-12-25 18:22 reprap? 2013-12-25 18:22 3D printer 2013-12-25 18:22 sure, there could be about three guys in entire RU doing that 2013-12-25 18:22 o.O 2013-12-25 18:22 duh! weird 2013-12-25 18:22 it's a very expensive hobby 2013-12-25 18:23 with $100/l resins? no way 2013-12-25 18:23 I thought particularly russian guys should be very interested in that sort of "let's see what can get done" 2013-12-25 18:24 they are. but with docs mainly in english, expensive hard-to-obtain resins with possible customs complications... very few people are going to go through that 2013-12-25 18:24 hmm, yet another weird idea: use a inkjet printhead to spit droplets of hardener into the 2 components resin bath 2013-12-25 18:25 1) afaik printerheads are very finely tuned to the specific consistency of ink 2013-12-25 18:25 2) you think it would harden fast enough? not sure 2013-12-25 18:25 (1) so the hardener wouldn't properly "boil out" or maybe will just flow through 2013-12-25 18:26 instead of epoxy "resin" you could go experimental and see what soluble glass gets you 2013-12-25 18:26 soluble glass? O_o 2013-12-25 18:26 ohhhh sodium silicate. I think it's sold here as glue 2013-12-25 18:26 that liquid based on silicon 2013-12-25 18:27 yeah 2013-12-25 18:27 sodium silcate 2013-12-25 18:27 you can add ethyl alcohol to it, it'll form a weird substance with nonlinear properties 2013-12-25 18:27 it hardens with some other chemical 2013-12-25 18:27 actually a number of other chemicals. Probably all metal salts 2013-12-25 18:27 at long timespans it flows. at medium it acts elastically (kinda like shitty rubber). at short it shatters in shards 2013-12-25 18:27 plus some acids prolly 2013-12-25 18:28 poor man's http://en.wikipedia.org/wiki/Silly_putty 2013-12-25 18:28 DocScrutinizer05: not sure about mechanical properties of the result 2013-12-25 18:29 me neither 2013-12-25 18:29 sounds like it would be fragile and/or weak 2013-12-25 18:29 well, that's a good start to do some experiments, no? 2013-12-25 18:29 yep, why not 2013-12-25 18:31 hm, it hardens because metal silicates form 2013-12-25 18:31 so that'll require a ton of metal salts 2013-12-25 18:32 quite possible, though i know it also hardens in free air, that's why it's been used to write on bottles with it 2013-12-25 18:32 maybe by the carbon from CO2 ? 2013-12-25 18:33 yup, also evaporation of water 2013-12-25 18:33 well, it's not water soluble once it hardened 2013-12-25 18:33 oh, it's not? I misremember then 2013-12-25 18:33 afaik not 2013-12-25 18:34 I think I heard it's been used for permanent writing on glass bottles 2013-12-25 18:34 mixed with chalk or some other pigment 2013-12-25 18:34 here it's used as a shitty paper glue 2013-12-25 18:34 like really shitty, it's really weak 2013-12-25 18:35 yeah 2013-12-25 18:35 it doesn't really glue at all 2013-12-25 18:35 about as much as salt water 2013-12-25 18:35 but it seems to even kinda mix with the glass of the bottles 2013-12-25 18:36 I dunno, just wild guessing here 2013-12-25 18:36 eh? how'd that happen 2013-12-25 18:37 I can't think of a substance that simply dries to a chrystaline form to really stick on glass bottles 2013-12-25 18:37 there must be more to it than just some shit drying 2013-12-25 18:37 van der waals forces can be quite high with glass 2013-12-25 18:37 and glass is also silica 2013-12-25 18:37 that uv curing epoxy is apparently used for gluing legs to glass tabletops 2013-12-25 18:38 and it sure as hell doesn't mix with glass... it's pure organic 2013-12-25 18:38 :nod: 2013-12-25 18:38 maybe the similar composition helps it somehow. I don't think they mix though 2013-12-25 18:38 the UV hardening acrylate glue I told wpwrak_ about 2013-12-25 18:38 yes, that's about the only thing I can find references to in russian 2013-12-25 18:38 not mix literally, for sure 2013-12-25 18:39 nothing _mixes_ with glass 2013-12-25 18:40 but some substances act on the surface of glass. E.G alkali substances tend to etch glass suface smooth 2013-12-25 18:41