#emc | Logs for 2010-04-13

[00:51:22] <andypugh> I changed a switch into a nested "if" and the arctan function went from 104uS to 4uS execution time. Blimey!
[00:53:26] <pfred1> I'm still forming capacitors over here
[00:54:34] <ds3> how are you forming a cap?
[00:55:22] <calcite> cylinder like?
[00:56:16] <pfred1> ds3 ds3 http://www.vcomp.co.uk/tech_tips/reform_caps/reform_caps.htm
[00:56:56] <calcite> I bought an old VFD (ebay) A 440 V unit, wired it up to 110 and left it sit for a day. It felt like I was being good to the caps ;>)
[00:57:22] <pfred1> I don't know if it works with non-polar caps or not
[00:57:55] <pfred1> I have seen some changes in some of the caps I've done this to though
[00:58:13] <pfred1> seems tapping them and discharging them helps some too
[01:03:06] <pfred1> it is nice to see some of the little buggers doing their jobs before i use them in a circuit
[01:09:01] <ds3> As the farad is too great a unit for practical purposes, the microfarad (MF)-one millionth of a farad-or its subdivisions are ordinarily used.
[01:09:08] <ds3> heh
[01:10:22] <pfred1> I think I've seen a picture someplace of a 1 farad capacitor
[01:10:41] <ds3> modern or ancient 1F cap?
[01:11:17] <pfred1> I can't remember I think it was modern it was on a pallet
[01:11:29] <ds3> heheh
[01:11:29] <pfred1> like by itself
[01:11:50] <ds3> I can hand you 1F cap that is smaller then a 1/2" EM
[01:11:51] <pfred1> had leads on it like high tension wire insulators
[01:15:26] <andypugh> I once dismantled a 2F capacitor. It was 2F @ 6kV.
[01:15:42] <ds3> while it was still charged?
[01:16:29] <andypugh> I admit it wasn't a single capacitor, it was most of a room full of 8" x 4" x 18" metal-cased, oil-filled caps interconnected with foot-wide copper strips alternated with polythene.
[01:16:58] <andypugh> Quite an expensive setup, I suspect. Part of a nuclear fusion experiment.
[01:18:32] <calcite> big cap banks can be seen in magnet charging systems
[01:19:36] <calcite> FerroTech In Nashua NH has walls lined with cabinets just to hold the caps.
[01:20:28] <ds3> guess they got plenty of capacity :D
[01:22:03] <andypugh> Not the same one, but the same sort of machine. This is a similar Z-pinch machine (and what a great picture it is too) http://www.sandia.gov/news-center/news-releases/2006/images/z-machine.jpg
[01:22:30] <ds3> I wonder how well would 6KV/1F work as a spot welder ;)
[01:23:40] <andypugh> That sandia one manages 2 billion degrees F.
[01:23:49] <calcite> illuminating!
[01:24:19] <calcite> an electric arc is the hottest thing a man can make.
[01:25:06] <andypugh> I think you might find that hydrogen fusion gets a lot hotter.
[01:25:36] <calcite> perhaps, perhaps not
[01:25:50] <andypugh> Nuclear fusion experiments are orders of magnitude hotter than the centre of the sun.
[01:27:25] <calcite> "Long before it's in the papers"
[01:27:25] <calcite> February 16, 2010
[01:27:25] <calcite> Physicists report creating hottest temperatures ever in lab
[01:27:25] <calcite> Feb. 16, 2010
[01:27:27] <calcite> Courtesy DOE/Brookhaven National Laboratory
[01:27:29] <calcite> and World Science staff
[01:27:31] <calcite> Phys­i­cists re­port that they have cre­at­ed mat­ter at the hot­test tem­per­a­ture ev­er reached in a lab­o­r­a­to­ry, about 250,000 times hot­ter than the cen­ter of the Sun.
[01:27:58] <andypugh> ITER is meant to reach 100,000,000 Kelvin.
[01:29:35] <calcite> temp of an electric arc? 11,0000 deg. F, or 6,000 deg. C. This is roughly the same temperature as the sun's photosphere, or outer visible layer.
[01:30:59] <calcite> heck, that's only 99999727 degrees C ...;-)
[01:31:15] <andypugh> That link you posted seemed to be to the RHIC? (I just googled the phrase) and that is 4,000,000,000,000 Celcius, which seems to win :-)
[01:32:09] <calcite> It's just an electric arc.... by definition of a plasma
[01:33:17] <andypugh> Hmm, I think that is stretching the point, it is a physical collision between ions. The energy is largely kinetic rather than elctrical (albeit alectrically accellerated)
[01:33:43] <calcite> It's all a stretch
[01:34:00] <andypugh> An electric arc is a plasma, but not all plasmas are electric arcs.
[01:35:00] <andypugh> And I think that that quark-gluon plasma (which is so hot that electrons themselves cease to be electrons) can't really be called "electric"
[01:35:29] <calcite> You mean my plasma metal cutter doesn't obtain temperatures near 4x10^12? I'm so disillusioned...;-)
[01:35:57] <andypugh> However, I think you are right that an electric arc is the hottest thing that this particular group of men could easily produce in the workshop at short notice :-)
[01:36:23] <calcite> My point ! Thank you for your generousity!
[01:36:53] <andypugh> Anyway, when I get this pedantic it is a sign I should be asleep.
[01:40:28] <calcite> does anyone know of a serial port application similar to "realterminal" that is ported to Linux? realterminal is not to the best of my awareness.
[02:00:38] <pfred1> she runs!
[02:01:22] <atmega> I find it helps to tie them up first
[02:01:34] <atmega> err... maybe that's the wrong 'she'
[02:04:07] <pfred1> my first bipolar chopper microstepping stepper motor drive
[02:04:22] <atmega> congrats
[02:04:40] <pfred1> thanks
[02:04:52] <pfred1> now i just have to figure out how it works
[02:09:35] <calcite> running is GOOD
[02:10:36] <atmega> ESTOP Out is high when EMC thinks the system is not e-stopped?
[02:11:01] <pfred1> can't you cnahge that?
[02:11:04] <pfred1> change even
[02:11:14] <atmega> you can invert, but is that the purpose of ESTOP out?
[02:11:39] <pfred1> I'd think estop is to throw a relay or something
[02:11:54] <pfred1> light up a panic lite?
[02:12:54] <atmega> I have a big red momentary switch, I want to use the NO contacts to signal e-stop. I want to use the NC contacts in series with ESTOP out to drive a SS relay that controls AC to the drives/spindle.
[02:13:29] <atmega> but, I'm not certain that's the appropriate thing to do.
[02:13:30] <pfred1> but a switch would go to an input
[02:13:48] <pfred1> you don't want to switch an output
[02:13:50] <atmega> right, the NO goes to ESTOP in
[02:14:08] <atmega> the NC in series with ESTOP out controls A/C
[02:14:25] <pfred1> emc can throw an estop from software
[02:14:42] <atmega> via ESTOP out? or what?
[02:14:44] <pfred1> like if you exceed soft limits or something
[02:14:54] <pfred1> I would hope that is how it works
[02:15:29] <pfred1> if it don't mach3 here i come :)
[02:15:49] <pfred1> no I'm sure that is how it works how else could it?
[02:16:57] <atmega> that is my assumption, I was looking for confirmation :)
[02:17:55] <pfred1> now I hear from some sources that some don't trust SS relays all the time
[02:18:09] <pfred1> seems like they have a habit to fry on or off or something
[02:18:22] <atmega> and they leak
[02:18:34] <pfred1> yeah they seem to have some issues to them
[02:18:53] <atmega> but, that's what I have at the moment.
[02:19:09] <pfred1> I got a whole box of relays big one little one all kinds of relays
[02:19:28] <pfred1> I'll probably rig a little one to trip a bigger one or something somehow
[02:19:29] <atmega> I have lots of little ones
[02:20:50] <pfred1> ok I think I've finally got my switch bank for this driver all mapped out here
[02:21:02] <atmega> if I were at work, I could put it in a nice box and make all the wiring pretty
[02:22:12] <pfred1> what are you like Jeckyl and Hyde or something?
[02:22:25] <atmega> yes
[02:22:43] <atmega> I have a compulsion to do it right, but no desire to spend money to do so.
[02:22:49] <pfred1> I am compelled to wire things up neatly
[02:23:38] <pfred1> I was working in this one shop and the guy who wired up these mahcines was on vacation so the foreman had me do one when the guy got back he was all pissed off because mine was nicer than he ever did them
[02:24:35] <atmega> heh... at work, if I do any wiring, I just make it work and get the techs to clean it up afterwards
[02:25:02] <pfred1> I was the tech I was wiring up the thing to sell
[02:25:11] <atmega> hten you should make it pretty
[02:25:58] <atmega> until you do install/startup and all the damned wires are run too tightly to fix that <wtf> that you forgot at the shop and then you have to cut all the tie wraps and one of the bundles is now too short
[02:26:27] <atmega> then come the but splices and electical tape
[02:26:39] <pfred1> not for me
[02:26:47] <pfred1> I solder and use shrink wrap
[02:27:02] <pfred1> I call those other things butthead splices ;0
[02:33:53] <pfred1> this hting is quite the toy!
[02:34:22] <Dave911> morfic: I just read your exchange on the motors and drives today, sounds like you are looking for bigger drives? If you want to go bigger than 3 KW, you are about to cross the magic price threshold into the more expensive drives and motors and the prices start climbing sharply.
[02:34:24] <Dave911> If price is not a big problem. I'd look at Siemens and Yaskawa servo drives and motors. Both are pretty much bullet proof. But they are not inexpensive. I believe that Yaskawa is the number one servo maker in the world followed by Siemens. AD is considered a really inexpensive industrial servo system. If you can get by with an AD type servo system you can install the AD servos, put...
[02:34:25] <Dave911> ...one on the shelf for a spare and still be much cheaper than the big guys Yaskawa and Siemens for the same size drives and motors.
[02:35:25] <morfic> Dave911: price is not the issue as getting another reliable source
[02:35:59] <morfic> Dave911: right, pay more for bigger is ok, i would not want to pay more for same specs
[02:36:28] <Dave911> Then I'd talk to both Siemens and Yaskawa. Siemens has a good service and support org. A lot of machine tools come from the EU with Siemens on them.
[02:37:00] <morfic> like X-Axis can be covered by 2kW or this 3kW servo, based on how i want to interpret the Fanuc spec, their max torque at top of intermittent zone is less than 2x the max torque on continuous zone
[02:37:13] <morfic> and SWPadnos already called AD's 2.5x-3x crap
[02:37:33] <Dave911> It is really about what works for you.
[02:37:46] <morfic> i contacted AD to get a little more info about it all
[02:38:14] <Dave911> I have some AD servos running on machines that operate outside (in the weather) and we haven't had any problems with them at all. Really bad conditions..
[02:38:17] <morfic> well, i will not push for a 5HP servo when boss already went "Johnny-Don, find 10HP servos and 40HP spindle"
[02:38:46] <morfic> the material we cut, we stall out the smaller Puma lathe easy, i need to compare the specs tomorrow
[02:38:52] <Dave911> He wants you to buy 10 hp servos??
[02:38:54] <morfic> if AD falls in between i migt be ok
[02:39:24] <morfic> Dave911: yeah, which is why i roll those numbers so long, he overshot w/o knowing what we need, so if i go lower, i want to be VERY sure i am ok
[02:39:37] <Dave911> I've used the 3 KW ADs on some custom machines and have also had zero failures.. good stuff.
[02:39:46] <morfic> look at X it's a 2.5HP servo
[02:39:58] <morfic> 4.7HP for Z
[02:40:34] <Dave911> Is the Z axis very heavy?? I saw you mention 2" drilling ?
[02:41:06] <morfic> so 3kW, electrically is fine, torque is closeish when you look at their thinner intermittent zone
[02:41:21] <morfic> the turret is pretty beafy
[02:41:41] <morfic> http://www.zerorealm.org/12LC/3-12-10_002.jpg seen this?
[02:42:00] <morfic> http://www.zerorealm.org/12LC/3-12-10_003.jpg
[02:43:35] <Dave911> I didn't see those before.. is that the machine?
[02:44:43] <morfic> Dave911: i could see it only affect acceleration, i think the AD can sustain a high speed, i am not clear if it can get there as fast, intermittent on Fanuc is ~38-39Nm tops based on their chart, Max torque for AD is 35.xNm, but AD pulls it across 2000RPM and only slightly drops around 2700RPM, while Fanuc holds those 38Nm up to 1500RPM then like goes to Zero
[02:44:45] <morfic> Dave911: that is the particular machine
[02:45:40] <Dave911> I've got a very similar lathe ... that i run with EMC2
[02:46:18] <morfic> Dave911: when we are roughing, we may take cuts heavy enough on cast bars (with nasty "knots" where the chillers and all was attached and burned off and ground) that the turret moves.......we do Fix "Y" often
[02:46:45] <Dave911> It has Siemens Servos on it.. I haven't checked their size exactly but they are in the 3-4 kw range...
[02:47:17] <Dave911> What do you mean by Fix Y??
[02:47:27] <morfic> Dave911: i think Fanuc us padding the numbers compared to industry standard, hence the smaller headroom to max intermittent zone torque
[02:47:58] <morfic> Dave911: fix rotation of turret, which means your turret is "off in Y", a Y your lathe should not have ;)
[02:49:11] <Dave911> Very possible. A lot of these guys play games some times. I have to admit that the AD number specs are very close to actual. We actual did some tests on them and I cannot say that they exaggerate.
[02:49:13] <morfic> we actually now EDM us a fork we can put in the turret in Tool1, and shim over a 2" bar we turn, we can adjust turret until gap above and below bar is equal, the reream the tapered pins
[02:49:54] <Dave911> Fix the Y axis ... ok, now I get it. That must be pretty ugly when that happens!
[02:50:15] <Dave911> Wow, perhaps you guys need to get a bigger lathe that can take the beating!
[02:50:29] <morfic> we have a bigger one too
[02:50:39] <Dave911> Oh.. ok.
[02:51:05] <morfic> and the small brother, and a smaller one we do not rough on for the tight tolerance stuff, that's small
[02:51:11] <Dave911> Well the KW of a Servo motor are really mostly used when doing rapids during accels.
[02:51:19] <morfic> but this one and the large one, we can take quite some cuts with
[02:51:55] <Dave911> When you are doing feeds even during heavy cuts, the motor loads are really not that great...
[02:52:12] <morfic> not typically
[02:52:33] <Dave911> The rapids are where you will get servo trips if the motors are slightly undersized..
[02:52:56] <morfic> Dave911: the AD drives provide outputs, i think i saw monitoring mentioned, can i get a load from that?
[02:53:59] <morfic> like we can see the load now on the Axis, SWPadnos said emc supports it if the data is provided, it should come from the drives, i guess i ask AD that as soon as i get a reply from them
[02:54:14] <Dave911> I doubt that you would have problems with the 3 KW AD drives and motors unless you are doing high speed rapids to change tools etc. Yes, you can send the output to a meter or another device to monitor and record the power output in percent of 100%
[02:54:39] <morfic> i spent so much time on the drives/servos, i need to take a step back and compile a list of questions CamSoft was asked, and then answer them for EMC
[02:54:53] <Dave911> I've used the AD analog output to monitor power out before... it works fine.
[02:55:42] <morfic> i would want EMC to monitor this especially on the mill and slow feed based on load during surfacing or based on application simple stop prior to a tool failure
[02:56:01] <Dave911> Are the ball screws on that lathe driven directly from the motors or is there is belt or gear reduction?
[02:56:08] <morfic> direct
[02:56:15] <morfic> 50mm on Z, 40mm on X
[02:56:21] <morfic> do not have the pitch yet
[02:56:55] <morfic> going to get with maintenance guy in the morning, he said we can get to Z Axis ball screw easy, X is a bitch he said
[02:57:04] <Dave911> EMC2 does have some form of adaptive feed. I asked about that before but I have never tried to implement it.
[02:57:13] <morfic> i take Z Axis pitch for now, to get an idea on feed force out of the Nm we have
[02:57:43] <morfic> SWPadnos said it's all there, just need the data to act on
[02:57:54] <morfic> how is AD support?
[02:58:01] <Dave911> My lathe has about the same size screws. The X screw is totally enclosed on mine.
[02:58:13] <morfic> hard to get a "knowledgeable" person on the phone?
[02:58:31] <Dave911> AD support is really very good. I have not had a problem getting a good guy on the phone when needed.
[02:58:35] <morfic> what's your lathe's make/model?
[02:58:57] <Dave911> Honestly, if you get the AD drives and install them, you will be amazed at how fast they setup.
[02:59:54] <morfic> i have no idea about servo setup, you talk about the "tuning the servo" part? (steep learning curve, i still vote for it, in the end *WE* know what's going on and we are better as a company yet)
[03:00:10] <Dave911> My lathe is a Monfort lathe, Model MNC 5. It is considered a hard turn lathe. It is totally overbuilt mechanically. It weighs 22,000 lbs..
[03:01:25] <Dave911> If you setup the EMC2 system and initially tune the motors off the machine, you can get a handle on tuning before you hook them to the screws..
[03:01:41] <Dave911> That should make the job a lot easier.
[03:02:43] <morfic> http://www.machineseeker.com/A695727.html looks small
[03:03:32] <morfic> tuning off the machine still gets the setup closer to running?
[03:04:34] <Dave911> The picture is deceiving. I think the machine is almost 20 feet long.. I just painted mine.. took a while..
[03:05:06] <morfic> Dave911: the impression of the machine being small could be mislead, by this bigger than needed frame :P
[03:05:16] <morfic> Dave911: what size chuck does it come with?
[03:05:50] <morfic> 200mm chuck? 8" chuck
[03:06:14] <morfic> the chuck you see on ours is a 15" chuck, so that would explain the feeling of it being small
[03:06:28] <Dave911> The MNC5 I have is setup for bar feeder work. I bought it from Timken roller bearing.. It has a 3" through hole and the chuck is about 14" hydraulic..
[03:07:22] <morfic> ah, nice
[03:07:30] <Dave911> It has a crazy big spindle motor with almost a direct 1:1 drive. I think it is 40 kw..
[03:07:49] <morfic> ours is only 22kW nominal, 26kW for 30mins
[03:08:23] <morfic> and that's the one with the AD drives/servos, right?
[03:08:42] <Dave911> 22 is pretty big. I have no idea how I could use the spindle motor on this MNC5 to full capacity, but there are not gears so it might be needed for low end torque...
[03:09:10] <morfic> we do have a gear box, 1035ft lbs in low gear
[03:09:10] <Dave911> No this machine has the same motors it originally came with. I had to replace one.. They are Siemens FT6 motors..
[03:09:26] <Dave911> A gearbox would be nice....
[03:10:02] <Dave911> I do custom controls work.
[03:11:05] <Dave911> I've used the 3 KW AD motors on two machines. Most of the AD motors and drives I have used have been the 1 KW models. Although I have used a couple of the 2 KW units also. They all setup the same.. so size doesn't matter from a controls standpoint.
[03:12:14] <morfic> you do custom controls work, you work as integrator of emc for others?
[03:12:30] <Dave911> EMC and other software...
[03:12:59] <morfic> Camsoft? power automations stuff? opencnc?
[03:14:12] <Dave911> I've never used Camsoft although I have talked with them... and I have chatted with the Power guys.. But I have used Siemens before.. quite a bit..
[03:14:32] <morfic> Dave911: do you do phone support? on-site?
[03:14:44] <Dave911> Sure ... this is all I do...
[03:16:03] <morfic> can i get you my email, i guess you have std rates that would apply? The way my boss wants a quote from Cradek about adding G71/G72 to EMC, he does want a quote from someone who actually integrated EMC as well before he would make final decision on EMC
[03:17:31] <morfic> If Cradek does phone/on-site aside from programming too, then boss would have more than one source for support once irc support is no longer enough
[03:17:44] <Dave911> Sure... send me an email to Dave at ColeControls dot com.. and we can talk..offline..
[03:18:16] <morfic> thanks, i will email you from work then, requesting rates
[03:18:29] <Dave911> Thanks ..
[03:19:10] <morfic> Thank You
[03:19:21] <Dave911> Anytime ...
[03:19:48] <Dave911> I think I am going to seek some rest now ... ;-)
[03:20:00] <Dave911> Have a good night! :-)
[03:20:19] <morfic> same here, thanks a lot for all the free info :)
[03:20:21] <morfic> 'night
[03:20:30] <pfred1> I have to get some more current sense resistors i hate how current is set on this IC
[06:08:03] <cliff_> Is anybody up at this hour?
[06:08:37] <cliff_> I am trying to setup a dual drive servo gantry and need some pointers... mostly where to start.
[06:27:18] <archivist> look for gantrykins
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[06:57:51] <micges> micges is now known as micges_machine
[08:11:24] <herron_> herron_ is now known as herron
[09:08:10] <awallin> any c++ people around? with a vector, I can do myvector.begin()+N to access element N from the beginning
[09:08:22] <awallin> with a list, mylist.begin()+N fails...
[09:09:04] <aystarik> yes, vector iterator can do add
[09:09:33] <aystarik> std only allows optimal operations.
[09:10:02] <aystarik> list::iterator + N depends on N, thus not implemented.
[09:10:49] <awallin> I need to insert and erase a lot of elements in the middle of a collection
[09:11:07] <awallin> I have it now with vector, but it seems slow, so I was going to try list
[09:11:31] <awallin> list should not have to move around/allocate memory when adding elements in the middle
[09:11:44] <awallin> I think that is slowing down my code now with vector
[09:12:05] <aystarik> well, you can do list::iterator ++ n times, if it is cheaper...
[09:12:27] <awallin> ok, trying.
[09:14:54] <awallin> also there is no operator[] ...
[09:16:05] <awallin> so, is there something better than list and vector, which would allow fast insertion and deletion in the middle, but also random access through operator[] ??
[09:18:08] <aystarik> there was rope<> in stlport...
[09:19:48] <aystarik> http://www.sgi.com/tech/stl/Rope.html
[09:20:48] <awallin> thanks, will have to look at that
[09:21:24] <awallin> or rewrite the code so it doesn't use integer indexes into the vector, but list-iterators everywhere instead
[09:22:00] <aystarik> second might be the better way
[09:28:22] <aystarik> or, you might want to insert into set, and then copy set to vector.
[09:40:23] <piasdom> g'mornin all
[10:25:18] <MarkusBec_away> MarkusBec_away is now known as MarkusBec
[10:28:44] <MarkusBec> MarkusBec is now known as MarkusBec_away
[10:34:39] <MarkusBec_away> MarkusBec_away is now known as MarkusBec
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[11:20:24] <awallin> more c++ questions: is a list-iterator invalidated by mylist.push_back()
[11:25:40] <The_Ball> I want to get a VFD for my mill motor. Do "all" VFD's support running in reverse? And if so, is it done with a seperate direction input or 50% PWM being the centerpoint?
[11:27:42] <robh__> The_Ball, some VFD u can set ether way, a input for forward & or reverse, or u can have analog or PWM etc input be split half way like you say, all down to make etc
[11:32:23] <The_Ball> robh__, ah makes sense, any mode preferred for EMC?
[11:35:20] <awallin> The_Ball: emc will output the spindle speed and direction as HAL-pins
[11:35:33] <awallin> what you do in HAL and hardware is up to you, no preference :)
[11:41:53] <The_Ball> very good, so with a encoder on the spindel when EMC starts the motor it will drive an enable signal to the drive high and start pulsing a PWM signal to the drive, will it use the encoder feedback to obtain the correct speed with a PID loop?
[11:44:11] <awallin> there is no PID-control for the spindle by default
[11:44:28] <awallin> but you can add a PID-loop yourself if you want.
[11:44:48] <awallin> if you have a good VFD it will keep the programmed RPM
[11:45:05] <awallin> if you have a cheap VFD you should be careful since the PID-loop could overdrive your motor
[11:45:11] <awallin> and result in technical smoke.
[11:45:30] <The_Ball> ah, good advice
[11:46:10] <awallin> my experience is that new "vector" type VFDs are much better than old "V/F" type VFDs
[11:47:14] <The_Ball> Ok, so I should get a good VFD for rigid tapping?
[11:49:34] <Valen> rather
[13:24:48] <morficmobile> 'morning
[13:25:45] <micges_work> hi
[13:42:06] <MarkusBec> MarkusBec is now known as MarkusBec_away
[13:44:18] <MarkusBec_away> MarkusBec_away is now known as MarkusBec
[14:20:07] <sealive> hi does someone now a font that is best for Styropor cuting
[14:20:38] <sealive> outline ok but the e,a,g has to be open
[14:21:39] <Jymmm> you forgot b d p q R o
[14:24:10] <skunkworks_> Jymmm: motor start relays and vfd mounted.
[14:24:11] <skunkworks_> http://electronicsam.com/images/KandT/conversion/packitin.JPG
[14:25:24] <Jymmm> skunkworks_: yeow! Did you get those relays from a 1880's telegraph system?
[14:25:45] <skunkworks_> heh
[14:25:49] <skunkworks_> almost
[14:26:12] <skunkworks_> the work great! (use heaters for overcurrent)
[14:26:20] <Jymmm> Well cool, it's coming along.
[14:27:03] <Jymmm> skunkworks_: On the SSR board, what are you using 22ga wire?
[14:27:20] <skunkworks_> the top one?
[14:27:24] <Jymmm> yeah
[14:27:36] <Jymmm> looks like the wires are coming thru a hole
[14:27:39] <skunkworks_> it is a multi conductor cable coming from the barcode reader..
[14:27:55] <skunkworks_> I ran the cable under the board.
[14:28:09] <Jymmm> Ok, I see it now coming from the top
[14:28:10] <skunkworks_> it comes from the top of the box
[14:28:12] <skunkworks_> yes
[14:28:36] <morficmobile> does +-10V vs "seven step" have a meaning for anyone in here? +-10V being the analog velocity signal we would be sending to the drive, "seven step" is a term i have not come across yet
[14:28:36] <Jymmm> skunkworks_: Say it with me... PAN DOO IT
[14:28:37] <skunkworks_> most of that stuff is going to be run with 24v
[14:29:49] <sealive> i fond some ViperSquadron looks nice to me
[14:29:52] <skunkworks_> Jymmm: heh. I am not sure how it is going to get dressed up yet. Not too worried about it.
[14:30:04] <Jymmm> skunkworks_: Well, it wasn't so much the 22ga itself, as much as no strain/stress relief. bump one of those wires and ooooops.
[14:32:04] <skunkworks_> who is going ot be bumping the wire? huh? are you going to come over and bend a bunch of the wire? Is that what you do? meanie!
[14:32:13] <skunkworks_> *wires ;)
[14:33:06] <Jymmm> skunkworks_: Hey you lil shit... wait till the wire breaks but the insulation is still intact so it appears that it's connected and you're going WTF?!
[14:33:40] <Jymmm> skunkworks_: wanna know HOW I know that?!?!?!
[14:33:51] <skunkworks_> Thats it! I don't like your attitude!
[14:34:30] <Jymmm> skunkworks_: Then install panduit and put on your big girl panties! not necessarily in that order
[14:37:39] <Jymmm> skunkworks_: how many control panels are you going to need for that machine of yours?
[14:39:13] <skunkworks_> Jymmm: we haven't really thought that far ahead.. one thougth is the monitor/jogwheels/keyboard would be on a swinging overhead mast. mouted to the corner of the upright.
[14:39:47] <skunkworks_> there still is a lot to get figure out before we get to that point.
[14:40:19] <skunkworks_> the actual interface will be the fun part at the end of the build ;)
[14:40:28] <Jymmm> Ok, the one your workin on now + operator's panel.
[14:41:13] <skunkworks_> sorry - yes. (I didn't quite pick up what you where putting down)
[14:41:29] <Jymmm> heh
[14:42:03] <skunkworks_> there are a bunch of estops sprinkled around the machine. plus a cycle start button on the other side...
[14:42:48] <skunkworks_> there are also a small panel at each pallet station for manual operation.
[14:43:13] <skunkworks_> I think I need a large white board at the shop for doodling.
[14:59:42] <elmo40> doodling is fun :)
[14:59:49] <elmo40> don't forget multiple colours.
[15:00:09] <skunkworks_> sure@
[15:16:13] <cnc4raffi> cnc4raffi is now known as kc6lbj-5
[15:24:13] <kc6lbj-5> kc6lbj-5 is now known as cnc4raffi
[16:34:37] <sealive> someone here that uses FreeMill
[16:35:51] <sealive> it works perfekt under WinXP but on Karmic wine1.2 it fails to save
[16:38:23] <Guest660> hi all , any idea when tne new emc will be available
[16:40:13] <sealive> look into the forum guest
[16:40:29] <sealive> 10.04 is just out
[16:53:48] <MarkusBec> MarkusBec is now known as MarkusBec_away
[17:15:04] <tom3p> newest release of pycam "This release features a new (experimental) simulation mode for visualizing the material cutting of a toolpath." http://freshmeat.net/projects/pycam
[17:25:29] <awallin> any screenshots?
[17:26:27] <atmega> what do you use to generate stl files?
[17:26:56] <skunkworks_> http://freshmeat.net/screenshots/20/da/20da304b4fd00210cb718a3cc43e552f_medium.png?1271116750
[17:27:33] <skunkworks_> http://freshmeat.net/screenshots/25/3d/253d22b8beec7ae36500fd8f9d79aa59_medium.png?1271116780
[17:28:22] <awallin> looks like its based on a single surface?
[17:28:39] <awallin> so undercuts would be a problem to visualize?
[17:29:35] <andypugh> I have a box outside my door for parcel deliveries. Some parts arrived today, but I can _not_ find the key for the lock. (And it has no reason to be anywhere other than on the hook inside, 6' from the box). I made a lock-pick. Imagine my surprise to find an extra plate at the back of the barrel that allows the whole barrel to just slide out! I think the "Parcel Safe" is a "Parcel not very safe at all really" but I suppose th
[17:29:35] <andypugh> would sell fewer.
[17:41:03] <Dave911> Andy: You are using the 7i43 LPT Mesa interface right?
[17:42:47] <Dave911> andypugh: are you there or are you hacking locks again... ;-)
[17:43:07] <andypugh> Sorry, I was hacking Arduionos
[17:43:16] <andypugh> Yes, I have a 7i43
[17:43:43] <morficmobile> AD have a nice disclaimer on their quotes "We do not guarantee our parts are suitable for your application." :)
[17:43:49] <Dave911> How much more CPU time does the 7i43 burn than a 5i20?? Any ideas?
[17:44:15] <andypugh> No idea. It burns a lot less than normal P-Port though.
[17:44:18] <Dave911> Morfic ... if you look at their VFD drives they aren't suitable for electric car conversions also... :-)
[17:44:22] <morficmobile> * morficmobile didn't want a quote, just more info on their specs
[17:45:12] <andypugh> To be fair, if you buy something and then find it won't do what you want, that ought to be your problem, not theirs. (Unless it was a specific recommendation, of course)
[17:45:37] <Dave911> andypugh: OK... thanks... that is significant. I guess I should ask PCW but I don't think he has been on today....
[17:46:25] <andypugh> As far as I can see the PC behaves just as though the card wasn't there.
[17:46:55] <Dave911> I'm thinking of adding a 7i43 to my next order.. if I don't need to use a PCI slot I can use a much smaller PC case.
[17:47:27] <Dave911> Are you using a special PCI LPT card? Or are you using a motherboard mounted LPT port?
[17:47:39] <andypugh> It can make wiring a lot neater too. Just one cable from PC to Control box, not 48.
[17:47:50] <andypugh> Motherboard LPT
[17:48:15] <andypugh> It's a 1U server, PCI slots are tricky.
[17:48:36] <Dave911> I thought I heard some people mention that some of the PCI LPT cards aren't always EPP compatible/compliant
[17:49:24] <Dave911> Morfic.. have you called AD? You might want to call their tech support folks. Sometimes they need to call you back but they are pretty good at that also..
[17:49:50] <Dave911> 1U server, nice and flat!
[17:50:29] <morficmobile> andypugh: right, but if someone asked for a recommendation it would be different
[17:50:43] <morficmobile> Dave911: just email right now
[17:51:14] <morficmobile> i just want to know how they define "continuous", to Fanuc that is "Continuous for 30 minutes"
[17:51:35] <Dave911> morfic.. Another cool thing about AD is their return policy.. it is pretty good. Almost... you don't like it, send it back...
[17:51:47] <morficmobile> good to know
[17:51:55] <andypugh> Hmm, to me "Continuous" means 24/7
[17:52:06] <morficmobile> andypugh: to me too
[17:52:22] <morficmobile> in which case 23Nm for 30 minutes would compare nice to 14Nm 24/7
[17:52:28] <morficmobile> so i want to hear it from them
[17:52:41] <morficmobile> 38Nm tops for Fanuc vs 35Nm tops for AD
[17:52:54] <morficmobile> top of their intermittent zone that is
[17:53:10] <Dave911> Continuous.... from what I have seen continuous is 24x7... seriously. I've tested the 1KW units really hard. As in "stall the motor and apply 100% torque for an very long time".... those machines I have running outside basically do just that...
[17:54:03] <morficmobile> but i get it from AD, this way i can show it to boss when he asks me why i consider "such a weak servo" ;)
[17:55:10] <Dave911> I agree... but you will get a lot faster response from a phone call... I don't know why.. but email sometimes get lost in their system ... or they consider it a lower priority than a phone call which sort of makes sense.
[17:55:21] <morficmobile> no good info from the company our CAD works with, Servos, yes, no VFD drive yet for our 22kW spindle
[17:55:59] <morficmobile> i am testing email replies, i can call tomorrow during day if i got nothing yet
[17:56:34] <Dave911> No biggie ... I just wanted to tell you what I have found with AD ....
[17:56:36] <morficmobile> ~24 hours from webinterface to human reply is not bad
[17:56:57] <morficmobile> now i want to see how fast a reply is to a reply to human :)
[17:57:01] <Dave911> I agree...
[17:57:08] <morficmobile> Dave911: do appreciate the pointer though
[17:57:18] <Dave911> NP.... :-)
[17:57:52] <morficmobile> should test boss' reaction to your rate :>
[17:58:17] <Dave911> andypugh: do you see any downside to using a 7i43 vs a 5i20 other than the number of 50 pin ports?
[17:58:33] <andypugh> Heading upstairs with Arduino and DAC0800
[17:59:09] <Dave911> morfic.... double it and tell him ... then when he reacts, tell him just kidding it is only half that .. ;-)
[18:00:10] <andypugh> I think that the 5i20 has higher throughput, and there are some .BIT files that are only released for 5i20 (The 6x Three-Phase PWM, 6x Encoder one, for example, but that isn't supported by the EMC driver anyway.
[18:01:33] <Dave911> ok... I did see more bit files for the 5i20 and didn't think about that.... Seems like PCW may be willing to make a custom one if I run into a jam though.... ??
[18:02:14] <andypugh> I have looked at making the driver support 3P-PWM but as I just had to check the docs to find the syntax for a C for-next loop I might be the wrong choice.
[18:02:36] <andypugh> Yes, he has already suggested that it is no difficulty to do so.
[18:03:26] <Dave911> Now Andy what did Einstein say about sticking stuff you can look up inside your head .. a waste of brain utilization or something like that ....
[18:04:17] <Dave911> Einstein had and also Edison had some very interesting quotes..
[18:05:11] <Dave911> I need to order a couple of boards so I have some spares for a startup... I think I will stick a 7i43 on the list so I can try it out. Seems like almost no downside ... thanks!
[18:05:40] <Dave911> I better get back to work .... bbl
[18:07:45] <andypugh> My £50 servos need £120 of connectors to do anything useful. That's annoying.
[18:08:37] <awallin> forget connectors and hard-wire everything... :)
[18:08:51] <andypugh> (Anyone know a cheap source for M23 conectors, female, 7 way and 12 way?)
[18:09:23] <archivist> M23, show me a pic
[18:09:32] <andypugh> I have considered hard-wiring, but I am more likely to make some terminals and use them without a shell.
[18:10:08] <andypugh> archivist: http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=0218905
[18:11:08] <archivist> not one I have used
[18:17:07] <bill2or3> new pycam is pretty nice.
[18:18:09] <atmega> bill2o3: what do you use to generate the files for pycam?
[18:21:14] <bill2or3> nothing yet, but I've been learning OpenSCAD
[18:22:41] <atmega> I tried blender for a while, that was way over my head.
[18:23:18] <bill2or3> heekscad looks promising, maybe check into it.
[18:25:02] <atmega> I have that installed, didn't spend much time on it though
[18:29:39] <morficmobile> <Dave911> Now Andy what did Einstein say about sticking stuff you can look up inside your head .. a waste of brain utilization or something like that .... <--- during apprenticeship we were taught not to memorize, just to learn how to use the info and where to find it.
[18:29:51] <morficmobile> interesting
[18:30:57] <archivist> but but, to look up stuph..you need books../me looks around oops too many books
[18:31:39] <tom3p> Dave911, dunno if Einstein said it but "a smart man knows everything, a wise man knows where to find it"
[18:47:36] <i_tarzan> edison may said 'i'm proud of havent built any destruction machine'
[18:50:40] <awallin> here's the latest octree cutting http://imagebin.ca/view/4bw_Ejiq.html
[18:50:53] <awallin> should be able to do simulations with cylindrical tools now...
[18:53:58] <awallin> although python is too slow for rendering these things in a reasonable time
[18:56:16] <awallin> gotta go, bye.
[20:33:23] <alex_joni> http://failblog.org/2010/04/13/epic-fail-photos-sign-fail-24-2/
[20:45:18] <MarkusBec_away> MarkusBec_away is now known as MarkusBec
[21:05:00] <MarkusBec> MarkusBec is now known as MarkusBec_away
[21:18:42] <frallzor> anyone into a nice software for woodworking?
[21:18:49] <frallzor> im not that into artcam =(
[21:31:59] <andypugh> frallzor: Tried Alibre? I amnot sure if it is anything like what you want, but it is free to find out.
[21:32:23] <frallzor> nah its not for carving afaik
[21:32:32] <frallzor> plain old cad
[21:33:53] <andypugh> 2D?
[21:34:27] <frallzor> cad/cam
[21:34:36] <frallzor> 2d and 3d I think
[21:34:44] <frallzor> but not suitable for making these kinds of models
[21:34:46] <andypugh> Alibre is cheap until you add CAM
[21:35:24] <andypugh> Ah, I have swapped the meaning of your "it" in that sentnce back there and things make sense now.
[21:36:26] <andypugh> Anybody know a nice single-supply DAC that doesn't require a clock bit? DAC0800 looked OK until it turned out to need a dual supply, and even when I made one wouldn't work.
[22:01:34] <archivist> andypugh, look for r2r types, ferranti ZNxxx (cant remember) even fabricate your own r2r
[22:02:03] <archivist> video dacs often used r2r
[22:04:00] <andypugh> Enough resistors for an R2R gets more expensive than an IC.
[22:04:18] <andypugh> But is probably easier to drive.
[22:04:27] <andypugh> I built one, but it works poorly...
[22:05:02] <andypugh> But then it is an R-2.2R which might be part of the problem.
[22:05:24] <archivist> we used an r2r on a video picture in picture thing we made a few hundred of
[22:08:26] <archivist> a Pollard high speed drill followed me home tonight
[22:08:33] <GonMD_> GonMD_ is now known as GonMD
[22:09:09] <archivist> 160420472109
[22:10:54] <pfred1> hey anyone here want to see a picture of my latest prototyped stepper motor driver?
[22:12:35] <pfred1> maybe I should have just asked hey anyone here?
[22:13:04] <archivist> just do it TM
[22:13:23] <pfred1> archivist swoosh!
[22:13:51] <pfred1> I have to keep reminding myself simpler is betterer
[22:14:42] <andypugh> I have used one of those drill, nice machines.
[22:15:21] <andypugh> Though I did have some trouble with the holes wandering. I was drilling a 0.3mm hole in a 3mm brass rod, trying to drill 20mm deep.
[22:15:25] <pfred1> andypugh once more with complete sentances?
[22:16:04] <pfred1> doesn't brass take special drills to drill?
[22:16:42] <archivist> when I went to pick it up I noticed the spingle is a bit bent but I got it anyway as they are not too common
[22:16:50] <pfred1> like for example you don't have the same geometry on a drill for brass as a drill for other materials
[22:16:53] <archivist> spindle
[22:17:34] <pfred1> archivist what'd you pick up bent?
[22:17:58] <archivist> ebay item 160420472109
[22:18:21] <archivist> otherwise its in very good condition
[22:18:29] <pfred1> Your search - ebay item 160420472109 - did not match any documents.
[22:18:45] <pfred1> I guess google can't handle ebay numbers
[22:18:48] <archivist> look for sold item
[22:19:50] <pfred1> archivist I have its cheap chinese cousin
[22:23:29] <pfred1> archivist http://img682.imageshack.us/img682/4395/drillboard.jpg
[22:24:30] <pfred1> spindle speed is too slow but it beats trying to drill with a Dremel I guess
[22:25:35] <andypugh> PCB drilling by hand? How quaint!
[22:25:36] <archivist> dunno, I use a dremel a lot and seem ok
[22:27:13] <pfred1> you got technique I don't have then because I manage to break a drill every other hole when I try using a Dremel to drill PCBs
[22:27:43] <pfred1> which is why I picked up the little drillpress i have
[22:27:59] <pfred1> it was cheaper than a Dremel too :)
[22:28:50] <pfred1> but someday I should try to change the motor in it for something a little faster
[22:29:11] <andypugh> Bigger motor pulley would be easier.
[22:29:17] <archivist> for fun drill a cross hole in a 1.5mm shaft
[22:29:29] <pfred1> andypugh thing hardly wants to start as it is
[22:29:41] <pfred1> on top speed it has to sind up to speed
[22:29:44] <pfred1> wind up even
[22:30:38] <andypugh> Ah, OK. More power is what you need then.
[22:31:03] <pfred1> thing like has a bobbin motor in it or something did i mention its a cheap chinese piece of junk?
[22:31:35] <pfred1> can't expect too much for $29.99 I guess
[22:32:15] <andypugh> No, that seems fair.
[22:32:38] <pfred1> I look at most chinese tooling as kits to be finished
[22:32:50] <pfred1> here have some castings have a good time so to speak
[22:33:51] <morfic> Dave911: AD replied quick, continuous is indefinitely at 100% of arated torque, the way it should be, not this Fanuc "Continuous for 30 minutes" crap
[22:34:24] <pfred1> morfic slap a fan on it you'll be fine
[22:34:52] <pfred1> I have a little MIG welder with a 20% duty cycle with a fan on it it's more like 60%
[22:35:12] <toastydeath> submerged in a bath of liquid nitrogen it's 100%
[22:35:30] <morfic> looks like we finally heard back from the place the other guy had been in contact with for months, for another project, Yaskawa: $5K for X, $6K for Z, $21K for VFD 22kW boss commented how come machines cost so much if drives are this cheap.
[22:36:13] <pfred1> morfic thats an easy one because everyone loves money!
[22:36:42] <morfic> pfred1: that's what i said "because they wanna eat too" :)
[22:37:02] <pfred1> morfic too bad they want to eat on the beach in Hawaii huh?
[22:37:17] <morfic> :) something like that
[22:37:52] <pfred1> sometimes greed can be counterproductive
[22:38:25] <morfic> it should occur to my boss that he has been planning on building a machine for months, and we did not know jack shit about it until now.....i mean there was no info on anything he had researched up until now that would be useful to retrofit let alone build a machine
[22:38:53] <morfic> he, being the CAD guy working on that machine with my boss
[22:39:41] <pfred1> I ordered some more motors for my hobby machine today
[22:40:01] <pfred1> I shot the wad: a big $14.95 a piece!
[22:40:21] <morfic> i am tempted to say: 1) AD Motors would 100% sure drive X, most likely Z 2) boss will likely go with the big specs for big $
[22:40:38] <morfic> pfred1: now that's more my hobby budget
[22:40:47] <pfred1> http://www.alltronics.com/cgi-bin/item/28M069/154/Lin-Engineering-5718L-12E-01-Bipolar-stepper-motor
[22:40:53] <morfic> brb, pizza + kid
[22:41:11] <pfred1> slightly used
[22:41:24] <morfic> pulls rocks
[22:41:40] <morfic> i listen to my music through tubes that are NOS or pulls
[22:47:04] <pfred1> I need to get the right current sense resistors for my motor drivers though
[22:47:53] <atmega> anyone know how much current you can run through a pin in a DB9?
[22:48:17] <pfred1> the pin itself is what gauge?
[22:48:29] <pfred1> it'd depend on the tightness of the connector really
[22:49:47] <pfred1> atmega a good tight fit and 10-20 amps wouldn't suprise me
[22:51:15] <atmega> I was looking for some way to clean up my stepper wires
[22:51:36] <pfred1> some seem to use 1/4" phono jacks
[22:51:55] <atmega> that's a lot of phono plugs (and jacks)
[22:51:59] <pfred1> but you can only get two wires onto one of those
[22:52:05] <pfred1> yup
[22:52:16] <atmega> a db9 is pretty compact
[22:52:17] <andypugh> atmega: DB9 is rated 7A per pin.
[22:52:26] <atmega> cool
[22:52:37] <andypugh> If you get a high quality one. Some are 5A
[22:52:43] <atmega> wonder how much wire I can get in my crimp pins
[22:52:48] <pfred1> yeah it all comes down to the fit
[22:53:06] <atmega> I only have 2.3A motors
[22:53:12] <pfred1> pro setups use what DIN connectors?
[22:53:34] <atmega> they all seem to be mfg specific
[22:53:49] <pfred1> well stuff I've seen always reminds me of DIN style
[22:54:07] <andypugh> Mil-spec bayonets, M23 connectors, some others.
[22:54:14] <pfred1> I thought of using molex connectors like out of computers
[22:54:22] <pfred1> they're common enough
[22:54:28] <andypugh> As I said earlier, I need £140 of connectors to run my £50 of motors.
[22:54:29] <atmega> 4wire XLR thingies would be cool, but they seem to be difficult to source
[22:54:59] <pfred1> and the molexes in PCs are 4 pin too which is nice for stepper motors
[22:55:34] <atmega> I really hate those thigns
[22:56:03] <andypugh> If I was starting again, I would use Speakon connectors. Cheap, 20A / 240V rated, very solid and positive. Compact too.
[22:56:31] <pfred1> so far I'm using barrier strips
[22:56:43] <andypugh> http://www.neutrik.com/fr/en/audio/204_184671/speakON_Cable_Connectors_productlist.aspx
[22:56:46] <pfred1> I have a few packages of them so ...
[22:57:15] <andypugh> Specifically, http://www.neutrik.com/fr/en/audio/210_612654417/NL4FX_detail.aspx
[22:57:28] <andypugh> Which I now see is 40A 240V
[22:58:52] <pfred1> barrier strips! http://www.imagechicken.com/uploads/1269814572086495500.jpg
[22:59:12] <atmega> nice meters
[22:59:36] <pfred1> atmega yeah whenever i see them cheap I find it difficult to say no one cost me all of $3
[22:59:42] <atmega> cool
[23:00:09] <pfred1> I guess at that price I'll take all I can get
[23:01:57] <pfred1> I got good at fixing them too they both had the same problem the ground wire coming off the battery compartment internally rots on them
[23:02:40] <pfred1> the copper ends up looking like pistachio pudding
[23:03:24] <pfred1> change that wire and you're good to go!
[23:05:34] <pfred1> I picked up a really hashed Triplett for 75 cents but I still need to fix it up
[23:06:44] <pfred1> no wait I think I paid a quarter for it come to think of it now
[23:07:05] <pfred1> I gave the guy 75 cents total I bought a draw knife off him too
[23:09:25] <pfred1> atmega want to see an action shot of my latest motor driver?
[23:12:44] <pfred1> I think I'm going to dub this driver 10 for $10 because it only takes about $10 and uses 10 parts
[23:45:41] <morfic> pfred1: bring on the action shot
[23:46:09] <pfred1> morfic OK http://img580.imageshack.us/img580/8305/tb6560ahqnoflash1.jpg
[23:46:27] <pfred1> morfic can you see it spinning?
[23:46:53] <morfic> yep
[23:47:08] <pfred1> morfic cool!
[23:47:08] <morfic> slowshutter++
[23:47:18] <pfred1> yeah i did a no flash
[23:47:30] <pfred1> and it was spinning pretty good so ...
[23:48:04] <pfred1> its a piece of masking tape I drew some alternate black and red triangles on
[23:49:04] <morfic> looks more read than anything
[23:49:07] <morfic> red*
[23:49:44] <pfred1> the red does stand out more but i just cut a square divided it by teh corners and colored in each triangle
[23:50:09] <pfred1> I got a thing for hypnodiscs too
[23:50:35] <pfred1> morfic have you ever tried a hypnodisc?
[23:50:41] <morfic> what cam is that? Model "5MP-9EY"
[23:51:00] <morfic> pfred1: white with various length balck lines, seeing colors when you spin it?
[23:51:15] <pfred1> morfic my favorite is yellow and red
[23:51:20] <pfred1> I make my own
[23:51:45] <pfred1> and let me tell you when it starts to work they more than change colors!
[23:51:51] <morfic> never got into it, but used to stick things on motor and watched the colors when i was little, yes
[23:52:10] <pfred1> its more like an amusement park ride when it works
[23:52:13] <morfic> show me your favorite red/yellow, static
[23:52:23] <pfred1> you have the distinct sensation that you are shooting int oit
[23:52:56] <morfic> now i must ask how large you make them :)
[23:53:44] <pfred1> I made one once and by accident stumbled upon it then years later I researched it all and found what i like online I have to search for the name of the function
[23:53:57] <pfred1> morfic last one i made is about 2 feet in diameter
[23:55:54] <pfred1> morfic ah this is what makes a good hypnodisc its called a logarithmic spiral
[23:56:58] <pfred1> morfic do it someday make a disc put a logarithmic spiral on it color one side bright red the other bright yellow and spin it about 30-40 RPM and just stare into the middle of it
[23:57:16] <pfred1> I guarantee you you will be amazed
[23:57:52] <andypugh> Can I sue you if I turn out to be epileptic?
[23:58:00] <pfred1> first it changes to black and white then it can appear to jump positions then it'll reverse direction then it really happens
[23:58:29] <morfic> pfred1: should we get to the point we have servos on the table, hooked up to the computer, i will make sure we do the motion test "properly"
[23:58:34] <pfred1> andypugh if you do it for a while you do get pinched vision for a bit afterwards
[23:58:55] <pfred1> which is sort of messed up in and of itself
[23:59:06] <Jymmm> * Jymmm places 15 full spectrum strobe lamps on a variable oscillator in front of andypugh!
[23:59:24] <Jymmm> * Jymmm watches andypugh flop around like a fish out of water!
[23:59:40] <pfred1> I never tried a hypnodisc with a strobe yet I'm not sure if it'd enhance it or not
[23:59:48] <morfic> pfred1: drive 150mph for a while, then exit the autobahn and reenter city traffic at 30mph, also a very fun effect