#linuxcnc | Logs for 2012-02-09

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[02:04:06] <Jymmm> cradek: jepler Did you guys come up with a way to estimate "run time" by chance? I'm trying to get a idea on how to accomplish something liek that.
[02:05:02] <Loetmichel_> mornin'
[02:05:16] <Jymmm> hola
[02:05:51] <Loetmichel_> *jawn*
[02:06:44] <Loetmichel_> -15°c this morning says my car... and no garage... i SHOULD wake up 15 minutes earlier in winter, de defrost the car :-(
[02:06:50] <Loetmichel_> -de+to
[02:07:12] <Loetmichel_> was 15 minutes late to work... AGAIN :-(
[02:07:39] <Loetmichel_> s/cara/car windows
[02:08:05] <Jymmm> cant hose it off?
[02:08:53] <Jymmm> at 5F, I'd be more worried about starting the engine than anything else.
[02:17:53] <Jymmm> I'm lovin this lil propane heater. More so now that I can connect it to 20# tank instead of using 1# tanks.
[02:24:48] <Loetmichel_> Jymmm: hose it off?
[02:24:51] <Loetmichel_> with water?
[02:25:07] <Loetmichel_> 15 degrees celsius below the freezing pint?
[02:25:10] <Loetmichel_> point
[02:25:27] <seb_kuzminsky> i think jymm meant with isopropyl alcohol
[02:25:51] <Loetmichel_> ah... could do that
[02:26:37] <Loetmichel_> but it will freeze over as soon as i get on the road. been there, done tahtn , nearly got an accident because of it
[02:27:51] <Loetmichel_> (hosed the window with the builtin nozzles and winter window clean-> 50% alcohol... 20 secs free sight, than instant white front windshielt ;-)
[02:27:54] <Loetmichel_> -t+d
[08:25:29] * JT-Shop ponders the age old question "how do you vacuum the inside of the vacuum?"
[08:26:06] <archivist> some of us have more than one vacuum
[08:26:39] <JT-Shop> I knew there was a trick
[08:26:48] <archivist> actually I have a qty of them /me needs to sell a few
[08:26:56] <JT-Shop> dang I'm wore out from yesterday
[08:27:44] <archivist> you have more "looking after" to do today :)
[08:28:21] <JT-Shop> actually she is supposed to get up and walk often, just no lifting, bending, twisting etc.
[08:28:46] <JT-Shop> but I still fixed her breakfast in the chair
[08:53:55] <archivist> hmm, apt programming book in the post :)
[09:41:52] <mazafaka> i had been using a tape see-saw several last days. Lots of the blanks had bee' prepared for the work, what a great time!
[09:42:48] <mazafaka> And this day is a holiday, what a great time!
[09:43:58] <mazafaka> And for all the overwork I'll then take from those greedy taking to the needin' (to myself, to my money account), what a great time!
[09:50:30] <cradek> sirhoax: no, I'm in Lincoln NE USA
[09:50:43] <mazafaka> On this holy day, work could had been set my way, and could last the lifetime pretty well, making a great time!
[09:51:21] <cradek> Jymmm: there's an estimate in AXIS, it's in the File/Properties window
[09:53:42] <jthornton> I must be missing a bunch of posts here as nothing makes sense
[09:53:55] <cradek> archivist: if we see cncjerry again let's ask to see the gcode
[09:55:58] <cradek> jthornton: I'm responding to old questions, directed at me, yesterday
[09:56:11] <jthornton> ok, had me wondering :)
[09:56:22] <cradek> jthornton: but I also don't understand what mazafaka is talking about, so maybe I missed something there
[09:56:26] <jthornton> it has happened to me before
[09:56:40] <jthornton> I don't understand either
[09:56:52] <mazafaka> something like http://www.youtube.com/watch?v=Uc2koTGsKAQ
[09:58:05] <mazafaka> Damn drilling machine makes the gears sound in my had even after the work, makes it! Ah-ha-ha-ha-ha!
[09:59:10] <mazafaka> I think it's the oil pump is so much noisy.
[12:06:17] <Loetmichel_> *bah! what a MESS!* note to self: cutting more than 0,2mm will stop the spindle of the C0. Next time: not sawing the square stock with 5mm plus material. :-( -> http://www.cyrom.org/palbum/main.php?g2_itemId=12794
[12:07:39] <Jymmm> not sawing???
[12:07:43] <Jymmm> not miling?
[12:10:17] <Jymmm> I need a diode for my solar panel to prevent from draining the battery ay night. I was going to use a 1N4001, but someone said to use something else because it has a lower Vfwd, anyone know what that might be?
[12:11:42] <mazafaka> Why do one need a micro lathe? For the items of micro world maybe?
[12:12:18] <Jymmm> mazafaka: Look ay your cellphone =)
[12:12:21] <Jymmm> at
[12:12:49] <mazafaka> for what?
[12:13:56] <Jymmm> mazafaka: You live in a micro world (your cellphone) and just don't know it yet =)
[12:14:59] <mazafaka> I'm big enough!!! And besides I eat macro-apples from a huge tree!
[12:17:50] <archivist> Jymmm, http://en.wikipedia.org/wiki/Schottky_diode
[12:18:50] <sirhoax> anyone use cambam ?
[12:25:55] <Gromits> Anyone know where there are instructions for installing linuxcnc from a usb flashdrive rather than a liveCD?
[12:27:03] <mazafaka> there's something in the linuxcnc how-to
[12:30:53] <Gromits> hmm, not finding it. I see instructions on installing it with a livecd to run on a usb flashdrive, but not how to install from a flashdrive...
[12:35:32] <Jymmm> archivist: thanks
[12:39:26] <Gromits> wikipedia comes through.... http://en.wikipedia.org/wiki/Ubuntu_Live_USB_creator
[12:41:25] <pcw_home> Jymmm you can use a MOSFET if you want ~0 drop (drive gate with tiny 5V solar panel)
[12:42:34] <sirhoax> or make a minder circuit.
[12:42:45] <sirhoax> cuts the circuit on no light condition.
[12:43:19] <sirhoax> have some small VW trickle charge battery keeper panels here.
[12:43:32] <sirhoax> been meaning to use them for small applications.
[12:45:16] <sirhoax> http://tinyurl.com/8xqpln5
[12:45:32] <tom3p> archivist, is the apt book by Kral? i found deal at Powells, like 30$ and great condition
[12:47:24] <tom3p> or where the 360 came from in Apt360 :) http://books.google.com/books?id=DafkAAAAMAAJ&source=gbs_similarbooks
[12:49:00] <archivist> tom3p, yes thats the one I think mine is on its way costing me a similay amount £20
[12:50:50] <tom3p> good on you! its a great book too
[12:52:09] <archivist> I couldnt find a cheap one in the uk so waiting for shipping from US
[12:54:11] <tom3p> i was surprised i couldnt dig one up thru the library networks in Chicago, even tried while in NYC. but good, i hope the best for the Apt crew
[12:56:40] <archivist> at least the main dev has kept watching irc even if busy doing something else
[12:59:13] <Jymmm> pcw_home: My Main intension is to build it into the connector and abuse proof it (epoxy encapsulation)
[13:02:52] <Jymmm> I eventually need to look at battery charging chips (LiPo, LiFePo, Ni-Cad, Ni-MH, etc) one of these days.
[13:07:30] <Jymmm> http://www.powerwerx.com/digital-meters/doc-wattson-meter-dc-inline.html
[13:10:51] <awallin> http://www.youtube.com/watch?v=CMNalKC2Rqc
[13:12:49] <cradek> awesome
[13:15:25] <awallin> similar-ish "wavefront-propagation" ideas are used in many "HSM" pocketing strategies. I'll try to start from something simple first..
[13:31:51] <mrsun_> awallin, what is that? :)
[13:34:45] <Loetmichel_> so, turning done, now some threaded holes and then the rest of the spindle parts... -> http://www.cyrom.org/palbum/main.php?g2_itemId=12797
[13:35:31] <clytle374> Jymmm, I think you can get that same meter for rc use much cheaper
[13:36:05] <clytle374> I've got a $20 one that looks exactly like it
[13:37:36] <clytle374> Jymmm, http://hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=10080
[13:42:25] <mrsun_> awallin, do you have any documentation on how to use your opencamlib? :)
[13:49:48] <sirhoax> these also work well for solar applications http://tinyurl.com/7qgkne2
[13:50:53] <sirhoax> you could have the display and shunt separate, remote monitor.
[13:50:57] <sirhoax> not sure how far you can extend it.
[13:51:31] <Jymmm> It's the shunt that makes the differnce there.
[13:51:57] <Jymmm> And realy wouldn't want to have a seperate PS for a meter/guage
[13:53:59] <Jymmm> Hubba hubba http://pinterest.com/pin/250160954271120923/
[13:54:23] <clytle374> The higher end one might have a better shunt. The cheap one can be powered either way
[13:56:14] <sirhoax> can make your own shunt.
[13:56:22] <sirhoax> just need to get 1mV per A
[13:56:30] <sirhoax> and a small meter.
[13:56:40] <Jymmm> I like the hobby one, can be plugged in-line as needed or removed. I use power pole connectors for everything
[13:57:00] <clytle374> I used a piece of wire the right length before I got the meter
[13:57:30] <Jymmm> I have shitloads of Ni-Chrome around here too.
[13:57:45] <sirhoax> yea you just get 12gauge wire. and a constant amperage source at 1amp. and adjust the length until you get the right mV drop on the wire.
[13:58:01] <sirhoax> free shunt ;-)
[13:58:48] <clytle374> I got the meter since flaming RC helies aren't much fun
[13:59:05] <Jymmm> I should have bought those 0.1Ohm 100W 1% resistors when I saw them
[14:01:40] <clytle374> Yep, they would be in the box with the Tesla capacitors I couldn't pass up ;)
[14:05:11] <sirhoax> http://www.cambam.info/doc/plus/tutorials/Drilling.htm
[14:05:24] <sirhoax> neato'
[14:06:40] <Jymmm> 1001 Things to do with a drill press?
[14:07:39] <sirhoax> yup. just another thing to add to the list of many things to try w/a cnc ;-)
[14:07:50] <Jymmm> does look pretty good though
[14:09:59] <tom3p> on the mailing list theres a longish thread about fp & modern cpu's
[14:10:02] <tom3p> isnt the idea really that realtime threads dont use fp? that fp is done in user space comps?
[14:11:09] <cradek> no
[14:11:35] <cradek> fp is optional in realtime threads
[14:11:59] <cradek> you can run the thread faster if you don't need fp
[14:13:35] <tom3p> ah! great. i had that all wrong & wrote a bazillion integer only comp version of existing ones ( tho now its true their thread could be faster )
[14:13:38] <tom3p> thx
[14:14:51] <mazafaka> i like to drill with 315 rpm and 0.060 mm as a feed rate per the revolution. this way, the chip breaks easily and the drill bit also works like an end mill bit.
[14:15:41] <mazafaka> I have asked the employer for a second drilling machine because I am idling while the first machine drills the metal.
[14:20:08] <mazafaka> 8 or 12 holes in 240 items or so, it makes a huge work. Each time you fix a new pocket of details (e.g. about 4 or 5 in the column) you have to clean the table out of the chips and sharp tiny chip produced by the center of the drill bit.
[14:21:28] <mazafaka> there's ice in the coolant sometimes. in -30 or so Celsius, it's very cold in the shop.
[14:24:18] <tom3p> get a 2nd machine that can drill upside down ( when we had production edm we mounted work on ram and tools on table... dirt falls down :)
[14:38:17] <mazafaka> yeah. this way, the fastest drilling is on the lathe, because the chip goes down ('pouring off')
[14:38:31] <clytle374> I've got precise running the 2.6.38 kernel. Trying rtai as soon as I figure out what weird option Ubuntu has in the kernel that kept root being read only
[15:29:11] <cstop> Question about stepper indexing. Is there a method that addresses errors between the division of a full circle and the logical step increments determined by motor steps per rev and gear ratio?
[15:29:47] <cstop> The example would be in gear cutting. Will all the errors present themselves on the last tooth? Hypothetical
[15:29:48] <cradek> to some extent, microstepping smooths that
[15:30:02] <cradek> oh wait, maybe you're asking about something else
[15:30:11] <archivist> cstop, the errors will be distributed
[15:30:28] <cradek> yes you always place the motor at the closest possible position to the desired one
[15:30:33] <cstop> is that a function of G-code?
[15:30:52] <cradek> no, it's something you don't need to worry about when writing gcode
[15:31:08] <cradek> just program your desired positions, whether in inches/mm/degrees
[15:31:08] <archivist> the machine controller, just be as accurate as you can
[15:31:51] <archivist> cstop, make sure your resolution is high enough that your errors are small enough
[15:31:59] <cstop> as in Degrees minutes seconds or as accurate as 200 divisions of 360 degrees?
[15:32:21] <cradek> you would never have a rotary axis turned directly by a stepper motor
[15:32:30] <cstop> I can not change the resolution or can I?
[15:32:31] <cradek> there is a worm gear, just like you have threads on a leadscrew
[15:32:34] <archivist> cstop, for gear cutting I have worm division after the stepper
[15:32:49] <cstop> yes, 50:1
[15:32:58] <cstop> sorry, 40:1
[15:33:05] <archivist> better rotaries are 90-1
[15:33:13] <cstop> it's a regular dividing head
[15:33:26] <archivist> some cheap ones are 90:1
[15:33:32] <archivist> Vertex
[15:33:57] <cradek> so you'd get 8000 steps per revolution, or resolution of 1/22.x degree. but your drives will probably at least half-step, giving twice that
[15:34:05] <cstop> This is an oldie but goodie ;-)
[15:34:36] <cradek> but the important part is that the errors don't accumulate
[15:35:03] <cstop> cradek what part distrubutes the errors?
[15:35:06] <archivist> cstop, what I have measured with the lower division ratio rotaries are internal gearing error (cocked up some gears that way)
[15:35:41] <JT-Shop> is there a way to prevent jogging until an axis is homed?
[15:35:47] <archivist> you get a sawtooth error distribution
[15:37:19] <archivist> cstop, to test once you get going make a high count gear and then use a vernier over a set number of teeth and go all the way round
[15:38:01] <cstop> can you suggest the g-code that would divide a circle into 200 equal parts?
[15:38:35] <cstop> graduating dials ;-)
[15:38:59] <archivist> use an o code subroutine
[15:39:03] <JT-Shop> G0 A1.8
[15:40:06] <cstop> repetitions of 1.8 degree steps results in all the error shown on the final division...that does not work :-(
[15:41:08] <cstop> I've considered A91.8 and 181.8, but have not proven that useful. hence the question
[15:41:31] <mrsun_> how to measure the thickness of doublesided tape. ..
[15:41:36] <mrsun_> will not do it with calipers ;P
[15:41:44] <mrsun_> that thing is superstrong =)
[15:41:47] <JT-Shop> 360/200=1.8
[15:41:52] <cstop> micrometer on a piece of scrap
[15:42:14] <mrsun_> cstop, cant measure it without the glue being exposed? :P
[15:42:20] <mrsun_> ofc i could dust it with parting powder
[15:43:20] <cstop> JT-shop that is true 360/200 is 1.8 but the stepper gearing does not always land on an even step in many situations. This is not direct drive.
[15:43:26] <archivist> cstop, that basic for a gear (you need to modify) http://www.archivist.info/cnc/standard_clock_n_teeth.ngc
[15:49:51] <JT-Shop> you asked for the G code that would divide a circle into 200 parts... is that not the problem?
[15:52:19] <Jymmm> NOT FOR THE GINSU 2000!!! http://www.youtube.com/watch?v=4q7GCuWFsSs
[15:53:14] <archivist> cstop, it is a digital system (all digital systems have error due to the resolution) it is probable that your rotary will be a larger error term than the digital division
[15:53:33] <Jymmm> JT-Shop: BUT WAIT! There's more!!!
[15:54:40] <cradek> this is wrong: repetitions of 1.8 degree steps results in all the error shown on the final division...that does not work
[15:55:17] <Jymmm> cradek: overlap?
[15:55:24] <cradek> either you have a misunderstanding of what's going on and have not tried it, or you need to explain your observations when you tried it
[15:55:34] <archivist> with half step you will be to 1 part in 8000 approx all the way round, it does not accumulate the errors
[15:56:43] <Jymmm> Epiphany... In more than 20 years the phrase "But wait, there's more..." is still used even though cultures have changed.
[15:58:34] <cstop> thanks I'll read a bit, Ahh that subroutine takes care of my question I believe.
[15:59:04] <cstop> Ahh. The subroutine does the work! great
[15:59:45] <archivist> yup just edit the numbers where needed, you will see what they effect
[16:01:25] <archivist> you will likely also need to adjust the F values to suit your machine and materials
[16:01:59] <cstop> feeds are like that
[16:03:43] <cstop> so if the angle and tooth count coincide to equal a full circle, the G0 A0 after the sub "should result in no movement at all.
[16:03:48] <cstop> True?
[16:04:25] <cstop> affirmation of error compensation
[16:04:50] <archivist> no it will rotate back to 0 from 360
[16:05:57] * archivist would like a move to nearest 0 on a rotating axis after n turns
[16:06:27] <cstop> Oh, Certainly there is something special about continuation of rotation....
[16:06:57] <archivist> see wrapped rotary which may be ok for some cases
[16:07:21] <cstop> I do not require such moves at present
[16:07:49] <archivist> it bites you if making worms
[16:08:44] <cstop> for worm gears, would not slaving two axis be a suitable approach?
[16:09:13] <cradek> you can't do that in gcode, but you can easily move multiple axes together
[16:09:21] <cstop> So much of one results in so much of the other
[16:09:49] <archivist> G1 F.05 x-.063 Y[0-#20] Z[0-#5] A[0-#<rotation_angle>] (rotate blank 7 turns)
[16:10:13] <archivist> but the unwind is too damned slow
[16:11:06] <syyl_> hmmm
[16:11:07] <syyl_> http://dl.dropbox.com/u/24396704/wzw_spindel10.jpg
[16:11:10] <syyl_> toolchanger ;)
[16:11:16] <syyl_> looks a bit...
[16:11:18] <syyl_> strange ;)
[16:11:29] <syyl_> dont know if thats the right concept...
[16:11:34] <archivist> microscope
[16:12:11] <archivist> other tooling can hit the work
[16:12:43] <syyl_> jep
[16:12:50] <syyl_> hmm
[16:13:17] <archivist> and there is little space to insert a loose tool into the collet
[16:13:46] <archivist> so they stick out even more
[16:13:53] <mrsun_> haha archivist your machine is just thrown together of different kind of junk ? :)
[16:14:04] <syyl_> hmm
[16:14:09] <syyl_> many points against it
[16:14:09] <archivist> mrsun_, you just worked it out :)
[16:14:15] <syyl_> maybe..
[16:14:21] <syyl_> back to the sketching board ;)
[16:14:33] <archivist> mrsun_, genuine fugly
[16:14:50] <mrsun_> looks like something i wouldnt even throw at the cats
[16:14:51] <mrsun_> :P
[16:15:06] <archivist> syyl_, look at tormach tooling
[16:15:21] <syyl_> ah right, they have a toolchanger now?
[16:15:52] <archivist> no but the register is nice
[16:16:13] <archivist> you just need a rack to hold the tools
[16:17:15] <archivist> syyl_, are you intending to use standard tooling with 6mm shanks
[16:17:20] <syyl_> yes
[16:17:28] <syyl_> correct
[16:17:41] <archivist> hmm setting depth is a problem
[16:17:54] <syyl_> they will have a collar ring
[16:17:55] <mrsun_> archivist, but i guess, as long as it does the job =)
[16:18:08] <archivist> ah ok
[16:18:28] <syyl_> and after each change, it will go for a toollenghtprobe
[16:18:37] <syyl_> if the collar by itself is not accurate enough
[16:18:51] <syyl_> but, on our datron machines, that works fine
[16:18:59] <archivist> mrsun_, it was cutting gears before the z and x had steppers fitted
[16:19:02] <syyl_> under 1/100mm tolerance when changing tools...
[16:20:09] <archivist> at the moment I cannot imagine a method to set height with gear cutters
[16:20:35] <syyl_> optical?
[16:20:41] <syyl_> with a microscope?
[16:21:54] <archivist> needs measuring all the way round to take errors into account, shadow , video capture and software I think
[16:22:13] <mrsun_> archivist, setting the center point of the blank or what? :)
[16:22:57] <archivist> needs flank width at cutting depth depending on cut width one needs
[16:23:19] <archivist> and centre line and diameter
[16:24:18] <archivist> current method is microscope and make one see if its ok adjust, rinse repeat
[16:26:14] <archivist> reason is cycloidal clock teeth come to a point
[16:29:50] <tom3p> syyl that idea is common on 'milldrills' like fanuc/brother. here a diy interpretation http://home.insightbb.com/~joevicar3/Automatic_Tool_Changer_Plans.htm
[16:31:04] <tom3p> http://www.youtube.com/watch?v=i1ZcKoUSlqI
[16:32:38] <tom3p> tax time :)
[16:32:52] <Jymmm> http://i54.tinypic.com/14cco4k.jpg
[16:42:21] <sirhoax> you know your playing her cd-right now. ;-)
[16:42:38] <sirhoax> heh.
[16:43:30] <sirhoax> cornelius!
[16:43:40] * sirhoax snickers
[16:45:24] <syyl_> oh
[16:45:32] <syyl_> thats a good link, tom3p
[16:45:34] <syyl_> mh
[16:45:36] <syyl_> he left
[16:45:37] <syyl_> :(
[16:46:51] <sirhoax> damn hardware stores around here only sell 1/8" stock
[16:47:56] <sirhoax> for flat stock aluminum. atleast.
[16:58:14] <JT-Shop> and you can bet it is not 6061 but rather architectural aluminum... gummy soft junk
[16:58:55] <alex4nder-> yes
[16:58:59] <alex4nder-> so damn gummy
[17:00:41] <sirhoax> maybe worth talking with a scrap yard.
[17:01:11] <sirhoax> but i've seen them with signs saying, we don't sell.
[17:01:24] <sirhoax> thought it was odd. ;-q
[17:01:45] <sirhoax> but i guess they all aren't like that.
[17:01:47] <alex4nder-> do you live in alaska?
[17:02:09] <sirhoax> please translate.
[17:02:41] <JT-Shop> lol
[17:03:10] <alex4nder-> sirhoax: just buy some aluminum stock from a local metal supplier, or online.
[17:03:52] <sirhoax> k.
[17:04:03] <sirhoax> to each his own.
[17:04:15] <alex4nder-> oh.
[17:05:08] <sirhoax> they charge a lot over here. for 2x2 square stock. 3/8 wall steal.
[17:05:28] <sirhoax> so can only imagine aluminum prices.
[17:05:51] <alex4nder-> you could start smelting your own, using recycled aluminum cans.
[17:06:06] <sirhoax> heh. microwave forged.
[17:06:22] <sirhoax> need to crush it first.
[17:06:38] <sirhoax> into maybe a cube?
[17:06:46] <sirhoax> hydraulic. if anything.
[17:07:41] <sirhoax> my space is limited. just need scrap. for small test runs.
[18:50:02] <cstop> archivist and all: per my question above regarding indexing errors. I realize now that in this digital age, Absolute moves cure a host of ills. Not something easily accomplished with dividing plates and sector arms. Thank you
[19:24:21] <skunkworks_> pcw_home: :) http://www.cnczone.com/forums/controller_computer_solutions/147097-galil_dmc-1050_controller_retrofit.html
[19:34:39] <Jymmm> JT-Shop: jthornton http://spoonforkbacon.com/2012/01/baked-egg-boats/
[19:39:15] <cstop> skunkworks Is the Mesa 5i25 and a 7i77 a good choice to retrofit a Commercial VMC? I admit bewilderment with all the options.
[19:47:19] <skunkworks_> cstop: what do you need? The 5i25 + 7i77 gives you 6 analog axis (6 +/-10v + 6 encoder counters) plus 48 isolated i/o. (plus it is very expandable)
[19:48:23] <skunkworks_> (mesa stuff is awesome)
[19:56:42] <cstop> That would seem to be enough. Present control is Sharnoa IV I don't have it in front of me, Just call it three axis/ plus a rotab and tool changer.
[19:57:22] <cstop> Presently no spindle encoder, just orientation for the TC. Something I would like to add.
[19:58:21] <cstop> You prefer Mesa over pico?
[19:58:36] <skunkworks_> I have only used mesa...
[19:58:59] <cstop> (Again, all these options are daunting for me to sort out
[20:00:05] <skunkworks_> I would take pci over printer port interface..
[20:00:43] <skunkworks_> (although mesa also has a printer port option)
[20:00:55] <cstop> Well, you must have done well to have a favorable impression. I was reading the Mesa literature, trying to understand the difference between the 5i20 and the 5i25. (two for one when it comes to $) Most of what was written was lost on me.
[20:02:20] <cstop> Does adding daughter cards to a pci "adder board" get cumbersome with ribbon cables running out of the PC chassis?
[20:02:39] <skunkworks_> heh - depends on how neat you are..
[20:03:15] <skunkworks_> http://electronicsam.com/images/KandT/conversion/panel/electricalbox.jpg
[20:03:32] <skunkworks_> that is 2 mesa 5i20's and a 7i33 and 7i48
[20:03:50] <Tom_itx> or don't use a pc chassis
[20:04:36] <cstop> how do you get the pci "slot" to the board?
[20:05:19] <cstop> in the case of no PC chassis
[20:06:14] <Tom_itx> just plug it in and figure out a way to support the tab
[20:06:16] <cstop> skunkworks What is the large black panel in the lower right of the upper section?
[20:06:57] <skunkworks_> 3 servo drives
[20:07:10] <cstop> Ahh yes, I see that now.
[20:08:16] <Jymmm> ...and no pandit for you!
[20:08:20] <Jymmm> NEXT!
[20:08:28] <Jymmm> (panduit)
[20:08:32] <cstop> you must have close to 48 I/O in that panel ;-)
[20:08:46] <skunkworks_> 96 ish
[20:09:27] <cstop> Ahh, tell me. Is the machine pictured more sophisticated than a "typical VMC?
[20:09:47] <Jymmm> It's just MORE MACHNE! lol
[20:10:12] <Jymmm> skunkworks_: has the Mui Macho Machine
[20:10:34] <cstop> does it serve afternoon tea?
[20:10:41] <skunkworks_> it is a large horizontal machining center http://electronicsam.com/images/KandT/oldkandt.JPG
[20:11:04] <skunkworks_> pallets and all
[20:11:20] <Jymmm> skunkworks_: Man, you gettign a receding hairline in that pic.
[20:11:28] <skunkworks_> :)
[20:11:46] <cstop> All on EMC2?
[20:11:51] <skunkworks_> all!
[20:11:54] <Jymmm> skunkworks_: Hey, YOUR mahine is bigger than that?
[20:11:55] <skunkworks_> working awesome
[20:12:01] <cstop> Hats OFF!
[20:12:44] <cstop> Do you ever get attacked by wire harnesses while you dream?
[20:12:57] <skunkworks_> http://youtu.be/39q6kvrSBSk
[20:13:18] <sirhoax> what is that mechanism at the top?
[20:13:31] <skunkworks_> ^^
[20:14:04] <Jymmm> skunkworks_: CCW ?
[20:14:28] <sirhoax> holymotherof...
[20:14:49] <sirhoax> that tool changer is no joke.
[20:14:59] <sirhoax> look like it could hold a jackhammer.
[20:15:06] <skunkworks_> gets the job done - 60 tools
[20:15:33] <sirhoax> dam. thats nice.
[20:15:35] <Jymmm> skunkworks_: But, can it drill a pcb =)
[20:15:56] <skunkworks_> have not try.. should be no issue
[20:16:00] <sirhoax> i'll be satisfied with 5-10 tool changer.
[20:16:02] <sirhoax> heh
[20:16:09] <sirhoax> but now its all manually changed.
[20:16:48] <cstop> And from what I see in the video, IT's a WOODIE"!
[20:17:27] <skunkworks_> heh - storage space ;)
[20:17:33] <cstop> The rapids seem quick
[20:17:41] <skunkworks_> just 200ipm
[20:17:47] <sirhoax> what kind of steppers are on that thing?
[20:17:53] <sirhoax> amperage usage etc.
[20:17:53] <cstop> I can't think that fast
[20:18:05] <skunkworks_> http://youtu.be/1a0YpKfSGE8
[20:18:26] <skunkworks_> http://youtu.be/jAcFeVlftrw
[20:18:29] <cstop> they are servos yes?
[20:18:45] <sirhoax> like butter.
[20:20:03] <skunkworks_> yes - big ass servos
[20:20:41] <cstop> over 2 kw?
[20:20:57] <skunkworks_> http://youtu.be/QU_O_Z7Vv8c
[20:21:41] <skunkworks_> 6kw peak
[20:21:46] <sirhoax> heh. maybe you can make me an adapter for my ford van. want to change the engine. heh.
[20:22:15] <sirhoax> need a plate made. to adapt a mercedes diesel.
[20:22:21] <skunkworks_> the servos are drive limited (40A peak)
[20:22:30] <sirhoax> to the transmission.
[20:22:31] <sirhoax> heh.
[20:22:37] <sirhoax> my cnc can't do it.
[20:23:42] <skunkworks_> http://electronicsam.com/images/KandT/DSC_0242.JPG
[20:23:51] <cstop> Are the motors and drives matched? I have been trying to figure out a Yaskawa motor for about a week. Quat encoder and trapazoid but no resolvers
[20:25:39] <skunkworks_> nope - the servos are early 80's - the drives are reletivly current AMC
[20:25:44] <cstop> don't drop those on your toes
[20:27:48] <cstop> and so the current limit, still impressive performance
[20:28:29] <skunkworks_> A relatively inexpensive conversion (it was a bit of time because it initially had hydraulic servos)
[20:28:50] <skunkworks_> (again - am very happy with emc and mesa)
[20:28:54] <cstop> AMC's are 80Volt devices?
[20:29:13] <skunkworks_> these are 400v (but we are running 200v in)
[20:29:23] <skunkworks_> they make all kind
[20:29:38] <cstop> and may I ask, how did you apply the pair of 5i20's?
[20:30:16] <skunkworks_> what do you mean?
[20:30:42] <cstop> well, is there a logical split of function and task?
[20:30:53] <skunkworks_> not really
[20:31:17] <cstop> one is as good as the other, just another pin assignment?
[20:31:23] <skunkworks_> yup
[20:31:31] <cstop> sounds good!
[20:33:00] <skunkworks_> we have a large old nc lathe that we are thinking of the 5i25 for.
[20:34:15] <cstop> a logical start, the price tag is inviting
[20:34:54] <cstop> I think I paid $45 for a BoB
[20:36:29] <cstop> $90 for the 5i25 seems a bargin I may order one out soon.
[20:41:11] <skunkworks_> This is stuff you could only dream of 20 years ago. (requiring a small mortgage)
[20:44:38] <skunkworks_> for step generation and such - the bob would work fine with the 5i25
[20:45:28] <skunkworks_> (the 5i20 can emulate the pinout of 2 printer ports)
[20:46:17] <cstop> My thoughts. as well. S&D works well even with servo drives ;-)
[20:46:51] <cstop> I did not know that about the 5i25
[20:46:52] <skunkworks_> yes - but if you go servos - go true closed loop
[20:47:00] <cstop> yes
[20:47:31] <skunkworks_> it emulates the printer port but allows you to do high speed step gen and such...
[20:47:58] <cstop> Even as the technology becomes so available, It takes a going concern to keep these tools occupied.
[20:48:37] <cstop> I hate to think of all the "router tables" pushed to the back of the garage serving as shelving for more clutter
[20:48:59] <alex4nder-> that's a reason techshop is so enticing.
[20:49:48] <cstop> I'm wondering "how bad" "latency" can be and still have the 5i2X out perform a rwa paraport
[20:49:53] <cstop> raw
[20:50:40] <cstop> alex4nder what is techshop?
[20:51:25] <Tom_itx> they have the tools you pay a fee to use them i think
[20:51:36] <Tom_itx> 'membership'
[20:51:39] <cstop> co-op
[20:52:00] <cstop> sounds hard on tools ;-)
[20:52:15] <elmo40> sure does!
[20:52:15] <Tom_itx> they check you out on them first
[20:52:48] <Tom_itx> some are set up where you bring your own cutters
[20:52:54] <alex4nder-> yup
[20:53:22] <alex4nder-> you can reserve time on a lot of different gear
[20:53:29] <Tom_itx> incentive not to screw up
[20:53:52] <alex4nder-> but they make you go through classes (and pay for said classes) before you get anywhere near the hardware
[20:55:34] <cstop> I like the familiarity of my own hardware.
[20:55:40] <skunkworks_> latency can be worse.. you still want it to be well under 100us though...
[20:56:17] <cstop> what happens if it is high?
[20:56:43] <skunkworks_> you still need a solid 1ms servo thread.
[20:56:44] <cstop> does the magic smoke get out? ;-)
[20:56:58] <skunkworks_> it will not time things right
[20:57:20] <cstop> so cordinated moves become un-
[20:57:48] <cstop> curves and radius have notches in them?
[20:58:07] <skunkworks_> following error maybe
[20:58:23] <skunkworks_> you will get a realtime error..
[20:58:29] <cstop> no such thing with steppers ;-)
[20:58:53] <skunkworks_> sure there is
[20:59:02] <Valen> worse with steppers
[20:59:09] <cstop> RTE shut things down don't they?
[21:00:42] <cstop> now I'm puzzled, how can a stepper, without a closed loop, have a following error? What is it following?
[21:01:12] <skunkworks_> emc still 'closes the loop' with steppers - it is just interal to em
[21:01:16] <skunkworks_> lliunuxcnc
[21:01:40] <skunkworks_> you get an error - but may not stop things from running - they just may not run will... http://electronicsam.com/images/KandT/testing/atom/Screenshot-1.png
[21:01:52] <cstop> And if the 5i25 handles a g-code command as a point to point move, what is the negative side of a bit of jitter?
[21:02:20] <skunkworks_> no -
[21:04:30] <skunkworks_> 5i25 gets sent 'velocities' and sends back to linuxcnc 'positions' while linuxcnc keeps tweeking the velocities while reading the positions.. (that might not be a perfect explaination)
[21:05:09] <skunkworks_> it may be sending torque amounts or...
[21:05:31] <skunkworks_> whatever
[21:06:35] <skunkworks_> jitter effects how accurate the sent and received info is.
[21:07:50] <cstop> typical servo systems for machine tools run in velocity mode. That is, if the following error is large, the control tells the motor to speed up. both in +amd - directions.
[21:08:57] <cstop> I use "following error" not as a fault, but as the input that tells the servo to correct it's position. Perhaps "position difference" would be more acceptable.
[21:09:00] <skunkworks_> yes
[21:09:41] <skunkworks_> there is a limit to the error though - like my machine with estop if the following error is larger than .001"
[21:10:34] <cstop> yes, It would be informative to know just what that limit might be.
[21:11:27] <cstop> Skunk, what is that screen shot showing?
[21:13:03] <cstop> crap I just got outbid on a nice little servo motor with a resolver! ;-)
[21:13:31] <cstop> I wanted that resolver!
[21:16:12] <cstop> skunk your .001 restriction would seem overly constrained for a 4'X8' router table
[21:31:41] <skunkworks_> depends on what you need.. for a hmc it may be a bit large.. :)
[21:31:50] <skunkworks_> but it is adjustable by you
[21:41:52] <cstop> is that something in EMC?
[21:42:06] <cstop> I've not seen it
[21:42:33] <cstop> stuck in "stepgen"
[21:53:20] <skunkworks_> look in the ini
[22:09:18] <cstop> looking at the .ini of an example , I see {FERROR=1.270} and {MIN_FERROR =0.254}
[22:10:44] <cstop> What do those terms represent? This is the "stepper_mm.ini" file.
[22:35:22] <skunkworks_> min error is the minimum following error (at very slow velocities) ferror is the maximum error at maximum velocity (G0 speeds) it is linear between the two errors
[22:36:29] <skunkworks_> http://linuxcnc.org/docs/2.4/html/config_ini_config.html#sub:[AXIS]-section
[22:37:02] <Tom_itx> where do you get pulleys?
[22:37:10] <cstop> so error and programmed feed rate are not linked"
[22:37:58] <skunkworks_> cstop: ?
[22:38:05] <skunkworks_> Tom_itx: ebay?
[22:38:15] <Tom_itx> i can't think of the site...
[22:38:19] <Tom_itx> it's not sdp
[22:39:18] <skunkworks_> http://www.econobelt.com/
[22:39:22] <skunkworks_> that it?
[22:40:46] <Tom_itx> not the one i was thinking of
[22:40:59] <Tom_itx> i'm sure it will come to me eventually
[22:40:59] <cstop> OK I read the text..... thank you!
[22:43:25] <cstop> MIN_FERROR is proportional , but not readily grasped as to slope of the graph (per the example) linear?
[22:44:16] <cstop> and still, how does that relate to Latencey and the 5i525? Life is a mystery ;-)
[22:44:36] <cstop> two many fives
[22:50:22] <skunkworks_> only in abstract..
[22:55:01] <cstop> "Dave...Don't do that" says HAL as the modules are pulled...2001