#linuxcnc Logs

May 29 2020

#linuxcnc Calendar

12:03 AM CaptHindsight: I ran it at ~600W and it gets pretty hot without a fan
12:09 AM CaptHindsight: ~68V and 9A
12:09 AM jymmmm: CaptHindsight: I'm looking at 250 to 300W
12:13 AM CaptHindsight: watching video of the riots
12:21 AM jymmmm: which riots? where?
12:23 AM CaptHindsight: https://www.cnn.com/us/live-news/george-floyd-protest-updates-05-28-20/h_58a4d4f3a5e1df02d0793755ae84d86a
12:24 AM CaptHindsight: mainly Minneapolis, but als in many cities today
12:24 AM CaptHindsight: als/also
03:06 AM Loetmichel: mornin'
03:06 AM Loetmichel: hehe, all 5 3dprinters running, all with different parts... there IS a reason i have 4 ender3s (and my private Anet A8 which is printing tactile sqitch buttons in "glow in the dark" PLA). Really nice to have if you notice one day before delivery that something doesent work the way you thought it did... :-)
05:01 AM JT-Cave: morning
05:03 AM XXCoder: yo
05:36 AM Deejay: hi
05:59 AM XXCoder: fanastic videp JT-Cave making eccenter head
05:59 AM XXCoder: https://youtu.be/jaemIFvl3-0
06:12 AM JT-Cave: I use a 4 jaw chuck don't need a shim
06:14 AM XXCoder: nice
06:14 AM XXCoder: its pretty good if dont though
06:15 AM XXCoder: funny thing work has lots lathes
06:15 AM XXCoder: none of em is 4 jaw
06:32 AM JT-Cave: I have a 5C chuck that I use in the Samson and just hold it with the 4 jaw chuck
06:33 AM XXCoder: 5c?
06:33 AM JT-Cave: for bigger than 1 1/6" I just use the chuck
06:33 AM JT-Cave: collet
06:33 AM JT-Cave: the CHNC is a 16C collet chucker lathe
06:34 AM XXCoder: not too ffamiliar with lathe names lol
06:39 AM JT-Cave: https://www.westtool.com/supply/prod_page_hardinge_5c_16c_3j_collets.html
06:40 AM HexaCube: hmmm, can I take BLDC motors apart without risking to lose torque?
06:41 AM HexaCube: supposedly that happens with stepper motors even though it seems it's not entirely clear :P
06:41 AM XXCoder: hex yeah wondered about that. i took one apart once (it was dead one i got replacement for, but i repaired wiring (it was broken inside)
06:42 AM JT-Cave: gotta make some chicken feeders today, they have out grown the chick feeder already
08:33 AM miss0r: Tom_L: The inside thread was a M65x3.5
08:47 AM Loetmichel: Hmm, i think i am a little stressed... Just yelled thru the company: "ANYBODY SEEN THE INSULTION FOIL?" Coworker: "I'll better take my distance before you explode again because you cant find something!" *ouch*
08:55 AM miss0r: Loetmichel: Have you lost your tinfoil hat again?
09:03 AM Loetmichel: miss0r: no, want to mount a PCB a couple mm above a sheet of aluminium
09:04 AM Loetmichel: and i already searched for a cutstomer device 2 hours this morning. turned out the coworker up in the office carried it away to make some new labels for it... i nearly turned every box on the production floor over...
09:04 AM HexaCube: does someone know of another distributor etc. for an industrial BLDC? I only know OMC-stepperonline
09:04 AM HexaCube: located in the EU
09:05 AM HexaCube: nema 17 size or something around that size
09:06 AM Loetmichel: point is that i am usually a very relaxed person. if someone is frightend i would explode AGAIN something is very, very wrong.
09:07 AM Loetmichel: explode-> lose my temper
09:10 AM FinboySlick: Beware Loetmichel's teutonic terror!
09:12 AM FinboySlick: Kidding aside though, is it that people think you're angry when you're not really, or is it that you're finding yourself angry when you shouldn't be?
09:14 AM Loetmichel: then latter
09:14 AM Loetmichel: -n
10:46 AM dirty_d: https://photos.app.goo.gl/sRQuwfFNhnzEfxR46
10:47 AM dirty_d: I wonder if putting shellac on the surface and letting it dry before the finishing pass would give a better finish, the fuzzies are hard now
10:47 AM dirty_d: so i think they'd cut cleaner instead of tearing
10:47 AM dirty_d: and it soaks in a little so the wood that's being cut is harder
10:48 AM FinboySlick: I wouldn't know much about the effects of shellac, but what is it?
10:49 AM FinboySlick: Looks like a fossil or some sort of crater.
10:49 AM HexaCube: looks like the surface of the moon to me,a topographical map?
10:51 AM jymmmm: dirty_d: If that's wood, you cna use a green scotchbright pad to remove the fuzzies easily
10:52 AM dirty_d: there more teary fuzzies though
10:52 AM dirty_d: not the kind that come off
10:52 AM dirty_d: the kind that take wood with them
10:52 AM dirty_d: using hardwood instead of pine would probably be a lot better too
10:52 AM jymmmm: yu would be surprised, try it
10:53 AM dirty_d: FinboySlick, gale crater on mars
10:53 AM dirty_d: shellac is beetle spit, haha
10:53 AM dirty_d: or something
10:53 AM jymmmm: poop
10:53 AM dirty_d: dissolved in alcohol, dries really fast
10:53 AM dirty_d: treat to work with
10:57 AM Loetmichel: beetle poop, not spit
11:02 AM jymmmm: bee spit is honey
11:03 AM Loetmichel: predigested nectar ;)
11:24 AM jymmmm: Loetmichel: Can these REALLY do 150A? https://www.aliexpress.com/item/32746253460.html
11:28 AM Loetmichel: jymmmm: 404
11:31 AM dirty_d: jymmmm, I believe it
11:31 AM dirty_d: but its probably not meant to all day
12:06 PM unterhaus_: if it's using hall effect, I'm not sure why it wouldn't do it all day
12:09 PM Rab: Haha, they're probably using that wire as a shunt.
12:10 PM Rab: Not quite, but it's not hall effect. People describe the construction in the comments: https://ae01.alicdn.com/kf/Ud8ac96d8cd6842f0a8c35f7cf6406595M.jpg
12:11 PM Rab: 12ga wire.
12:14 PM Rab: 150A at any voltage will definitely put that silicone insulation to the test.
12:29 PM jymmmm: Rab: What about at 14.8@60A=888W ?
12:30 PM jymmmm: Loetmichel: works for me, reload?
12:31 PM jymmmm: unterhaus_: not hall effect, shunt
12:31 PM Rab: jymmmm, over what distance?
12:31 PM jymmmm: Rab: 18 inches?
12:33 PM jymmmm: Rab: and good pic, thanks
12:34 PM jymmmm: As I understand it 12ga has a max load of 60A, per the ratings charts I've seen. I'm HOPING that's continuous
12:35 PM Rab: 1.92% voltage drop over 18", means 18W dissipated in the wiring if my calculations are correct.
12:39 PM jymmmm: Rab: Hmmm, even at 10ga, not much difference in the voltage drop - https://www.calculator.net/voltage-drop-calculator.html?material=copper&wiresize=5.211&voltage=14.8&phase=dc&noofconductor=1&distance=1.5&distanceunit=feet&amperes=60&x=54&y=29
02:34 PM CaptHindsight: jymmmm: it's the insulation that melts and burns
02:35 PM CaptHindsight: the copper wire will melt at a much higher temp
02:44 PM Tom_L: miss0r, you around?
02:44 PM pcw_home: also the resistance will be ~40% higher at 125C
02:53 PM jymmmm: I see silicon wire used a lot in RC stuff. I had believed it was because it's soft and plyable, But I'm getting the impression that it's also heat factors due to the high amp draw???
02:53 PM Tom_L: yup
02:53 PM Tom_L: that or teflon
02:54 PM jymmmm: No teflon, that shit is expensive and a PITA to strip
02:54 PM Tom_L: no kidding?
02:55 PM jymmmm: I hated working with it
02:57 PM jymmmm: Just because it was gong on aircraft, and jsut because it was weapons systems, doens't mena I couldn't just go to radio shack and grab any spool of wire instead =)
02:57 PM Tom_L: i've got a few odd spools of it
02:58 PM CaptHindsight: 7mm (wide) rails and carriages came in
02:58 PM jymmmm: I even had fancy heated strippers specifically for teflon wire, still was a PITA
02:58 PM CaptHindsight: I thought I had seen smaller as some trade shows
02:59 PM jymmmm: CaptHindsight: 1/4"? what for?
02:59 PM CaptHindsight: non-contact, short movement, high speed
03:00 PM jymmmm: CaptHindsight: of?
03:00 PM CaptHindsight: low force and loads
03:00 PM Tom_L: jymmmm, i just use my teeth :)
03:00 PM jymmmm: Tom_L: gum it to death huh?
03:01 PM jymmmm: cause after 2 times using your teeth, that will all that be left... gums
03:02 PM CaptHindsight: https://www.mpsag.com/fileadmin/_processed_/d/b/csm_MPS-MS_PROD_RoulementL_002_Ble_Bloc-Blanc_a1f6a86c68.jpg
03:12 PM jymmmm: Is paralleling 2x30A fuses really legit for a 60A DC circuit (maybe shitty, but legit)???
03:21 PM HexaCube: doesn't sound like it would be :P
03:24 PM jymmmm: I didn't think so either at first, but it sorta kinda makes sense if you think of resistors in parallel HexaCube
03:25 PM jymmmm: Here's the interesting arguement... https://www.thirdgen.org/forums/electronics/11333-will-two-60-amp.html
03:26 PM dirty_d: wouldnt it sort of self stabilize
03:26 PM dirty_d: the hotter one gets, the higher resistance and so it would offload more current to the cooler fuse element
03:26 PM dirty_d: and the amount of heat generated is more influenced by the current, not the resistance
03:28 PM dirty_d: but a 60A fuse is rated to eventually blow at 60A right?
03:30 PM jymmmm: dirty_d: Yes, one 30A fuse would blow first, then the other one.
03:32 PM dirty_d: yea, but I mean even one 60A fuse will eventually blow at 60A
03:33 PM dirty_d: the rating is the rating that it will eventually blow at right?
03:33 PM jymmmm: dirty_d: If the load was 58A, then (theoretically) the load across EACH 30A fuse would be 29A. Assuming both fuses are IDENTICAL (in resistance), which in reality that won't be, so one fuse blows, the full 58A load will go across the other 30A fuse, and then blow it too.
03:33 PM dirty_d: right
03:34 PM jymmmm: It's a hellva lot easier and cheaper to find a 30A fuse than a 60A one
03:34 PM dirty_d: "A maximum current that the fuse can continuously conduct without interrupting the circuit."
03:35 PM dirty_d: jymmmm, just solder some thick copper wire where the fuse goes, what could go wrong?
03:36 PM dirty_d: jymmmm, what were you planning on using that for? I have one, but I've only used it like once
03:36 PM dirty_d: not that same one, I got it a long time ago
03:36 PM jymmmm: dirty_d: Since you asked what could go wrong... https://www.youtube.com/watch?v=I5qcnNgpyik
03:36 PM HexaCube: 60A at what voltage, btw?
03:37 PM HexaCube: shouldn't be too hard to find a 60A automotive fuse? :D
03:37 PM jymmmm: 14.8VDC@60A=888W
03:37 PM jymmmm: HexaCube: MAXI fuses are expensive
03:38 PM HexaCube: I'm seeing one for 43 cents? :P
03:40 PM jymmmm: HexaCube: ,lol,w where?
03:40 PM HexaCube: a german electronics store :P
03:41 PM jymmmm: $3.69 for a bolt on 100A fuse at autozone
03:41 PM HexaCube: (and that's expensive for you? :P)
03:41 PM jymmmm: oh crap, special order
03:42 PM HexaCube: depending on the task paralleling might work, I just wouldn't risk it because chances are they won't quite behave like the should
03:42 PM jymmmm: one way to find out =)
03:42 PM HexaCube: especially when you'd save like... 2USD :P
03:43 PM jymmmm: HexaCube: the 100A was special order, could even locate a 60A yet
03:43 PM jymmmm: could NOT*
03:44 PM dirty_d: jymmmm, you're talking about the fuses in that power meter, or something else?
03:44 PM jymmmm: HexaCube: IF 60A were easily availael most places, even walmart, then I don't have an issue. But it's been my luck that when I needed a not-everyday-fuse, that they become hard to find.
03:45 PM HexaCube: https://www.ebay.com/itm/60-AMP-AGU-Large-Fuse-Glass-Style-Amp-Car-RV-Boat-Solar-12V-24V-32V-60AMP-60A or get some of these
03:45 PM jymmmm: dirty_d: Just an added level of system protection is all, not that power meter
03:46 PM HexaCube: https://www.digikey.com/products/en/circuit-protection/fuses/139 also plenty to choose from hehe
03:46 PM jymmmm: HexaCube: I got a 404
03:46 PM HexaCube: jymmmm woops I cut the link too short, sorry
03:46 PM jymmmm: HexaCube: mail order is easy, try at 4pm on a sunday?
03:46 PM HexaCube: https://www.ebay.com/itm/60-AMP-AGU-Large-Fuse-Glass-Style-Amp-Car-RV-Boat-Solar-12V-24V-32V-60AMP-60A/281249946838
03:47 PM jymmmm: HexaCube: HA, I hate glass fuses =)
03:47 PM HexaCube: well, here any and all stores are closed on a sunday anyways, so I guess I don#t have that issue to begin with :P
03:47 PM jymmmm: HexaCube: even autoparts stores or walmart?
03:47 PM HexaCube: we don't even *have* a walmart :P
03:47 PM jymmmm: ok, some other mega outlet thingy
03:48 PM HexaCube: but yeah, I think only gas stations and restaurants etc. are open on sundays
03:48 PM HexaCube: but regular stores are all closed
03:48 PM HexaCube: Germany is stuck in the past on that topic
03:48 PM HexaCube: also I don't think we really have mega outlets like that either, a store where you can buy ANYTHING :D
03:49 PM jymmmm: You know those inline blade fuse holders with the little cap on them? Eh, screw that, I use .185" crimp on blade and some heat shrink =)
03:50 PM jymmmm: they fit PERFECTLY
03:51 PM HexaCube: hehe
03:51 PM jymmmm: nicer if they are right angle
03:51 PM HexaCube: I'm a little spoiled regarding that from work, building switching cabinets :D
03:51 PM HexaCube: nice and big components, just a lot of crimping :P
03:52 PM * HexaCube finishes his apparenticeship in 2 weeks, this is part of the final exam: https://i.imgur.com/Zmii00g.jpg
03:54 PM CaptHindsight: HexaCube: do you have to wire it blindfolded?
03:55 PM HexaCube: hah, no :P
03:55 PM HexaCube: https://i.imgur.com/mciFKXc.jpg that's the other part of the exam preparation
03:56 PM HexaCube: During the exam itself I'll have to change the program on the PLC, do some additional wiring, machine some parts, assemble and commission the machine :D All in 6 hours
03:59 PM jymmmm: HexaCube: DUDE!!! You are gonna fail, you have the din rail upside down!!!
03:59 PM HexaCube: haha
04:00 PM jymmmm: =)
04:00 PM HexaCube: worst part of the exam is remembering all the steps during commisioning really, but I'll manage :D
04:00 PM jymmmm: HexaCube: Looking at that, you should be fine =)
04:01 PM HexaCube: on the exam I had in the middle of the apprenticeship I felt like I screwed up and scored 94/100 points
04:01 PM HexaCube: and after this it's 2 more months of actual work, and then off to university *sigh*
04:01 PM jymmmm: engineering?
04:02 PM CaptHindsight: at least you get some practical experience
04:02 PM HexaCube: Yup. I do the apprenticeship as a 'mechatronics technician' and will be studying mechatronics afterwards
04:02 PM HexaCube: but it's a bachelor of engineering
04:02 PM jymmmm: very cool
04:02 PM HexaCube: (let's hope I don't fail right away :D)
04:02 PM HexaCube: CaptHindsight yeah, it was the reason I chose to do an apprenticeship
04:03 PM HexaCube: I didn't wanna spend another 4 years after graduating, I wanted to work and earn my own money first
04:03 PM CaptHindsight: you'll learn how that PLC works and almost how to design one
04:03 PM HexaCube: this year I realised I just don't quite like the type of job I'd have to do, and *then* I decided to study after
04:04 PM jymmmm: If you REALLY want to impress them... forget that panduit, use waxed string and make it so you can trace EVERY wire individually end-to-end, AND all cable bundles are self suspected in mid air. I've only seen this ONCE, and ws EXTREMELY impressive.
04:04 PM CaptHindsight: completely wire free would impress me :)
04:05 PM HexaCube: CaptHindsight industry 4.0 I see! :D
04:05 PM HexaCube: do it all over wifi
04:05 PM Deejay: gn8
04:05 PM CaptHindsight: even the power :p
04:05 PM jymmmm: CaptHindsight: Theye didn't even use clamps on the water cooling lines for the mosfets
04:05 PM jymmmm: this thing was a work of art to see it
04:06 PM HexaCube: I actually wish I learned a bit more about that, seems like a lot of cool stuff is going on with connecting machines etc.
04:06 PM HexaCube: I know our company develops apps and such to see the current machine status and such :P
04:07 PM jymmmm: HexaCube: This was in three 42U cabinets connected together, you could visually trace EACH wire from one end to the other. It was VERY impressives
04:08 PM HexaCube: hmmm, while that sounds really nice to see, it doesn't seem to represent a 'real job', does it?
04:08 PM HexaCube: in what context did you see that if I may ask?
04:08 PM jymmmm: Heh, the plant was half a mile long, EVERYONE knew when I was operating it =)
04:10 PM jymmmm: HexaCube: IT was the amplifer for a 10G enviromental virbation tester. The "coil" alone was powered by a 220VAC 3ph 100A circuit., I have no clue what the amp itself was powered with.
04:10 PM HexaCube: yow, beefy
04:10 PM jymmmm: HexaCube: just that it used water cooling, and the water tower was on the roof
04:11 PM HexaCube: heh
04:11 PM HexaCube: it's always humbling to hear about those sorta things. We build CNC Machines at work, and I always think the stuff we do is BIG hehe
04:11 PM jymmmm: HexaCube: Yeah, I guess way too many people were complaining, so I had to do vibration testing on second shift from then on
04:13 PM jymmmm: The vibraton table was 110LBs of 2" magnesium plate, on a granite plate, then hydraulic oil was pumped between them to reduce friction.
04:13 PM HexaCube: why magnesium?
04:13 PM jymmmm: The coil (like a speaker) was 3ft diameter and 12" deep
04:14 PM jymmmm: HexaCube: light weight compared to steel I'm guessing
04:15 PM HexaCube: actually, I guess you could call this one a large machine :P https://www.youtube.com/watch?v=cf43KILz0e8 I briefly helped build that one :D
04:16 PM HexaCube: the video has captions if anyone's curious ^^
04:19 PM jymmmm: Fuses are expensive now... $6 for five 15A https://www.amazon.com/Bussmann-BP-ATM-15-Acting-Mini-Fuse/dp/B0006IBYOW
04:20 PM jymmmm: $1.20/each
04:22 PM jymmmm: $10 for a MAXI fuse holder?!
04:38 PM CaptHindsight: https://imgur.com/gallery/6oVWRy2
04:47 PM jymmmm: CaptHindsight: So THAT's how bubleboy does it
04:52 PM dirty_d: I don't even need one, but I want one
05:12 PM andypugh: I had never heard of Grob until a bunch of machines got delivered to work.
05:14 PM andypugh: I bought a nice tenths indicator from that eBay. But was disappointed to find that (when it arrived) there was no ball on the end of the lever. This was clear in the auction photos, I just hadn’t noticed.
05:15 PM andypugh: I was trying to decide what to do, and was looking through my collection of Renishaw probes (much bigger thread, though) when I found one that I had broken the ruby ball off of. And, remarkably, the loose ruby ball that I had kept for some reason was a nice snug fit on the indicater lever.
05:15 PM andypugh: Result!
05:21 PM Tom_L: andypugh, if you ever _do_ need one: https://www.carbideprobes.com/
05:26 PM Tom_L: i got one for my last word indicator from them
05:48 PM jymmmm: andypugh: WOOHOO for hording =)
06:22 PM andypugh: Tom_L: I only paid £30 for the indicator. So the same for a tip isn’t an option. You can get then for <£5 from China, but not tomorrow.
06:34 PM veegee: Can anyone recommend a high power dehumidifier?
06:34 PM veegee: Or perhaps multiple cheaper smaller units I can run in parallel in the industrial unit?
06:34 PM veegee: I find humidity pushes me towards heat exhaustion very quickly.
06:35 PM veegee: I'll take my time finding an appropriate 100,000 BTU/h AC system and look for a good deal. The dehumidifiers seem to be _significantly_ cheaper
06:38 PM jymmmm: veegee: flame thrower?
06:38 PM veegee: I'm being serious
06:38 PM veegee: It also makes it harder for me to breathe, I have exercise induced asthma
06:39 PM jymmmm: Nuclear fusion should remove all humidity in 0.0000000000001 seconds
07:09 PM skunkworks: andypugh: that is why you never throw anyting away! And also why hoarding is an epidemic..
07:17 PM jymmmm: lol
07:17 PM jymmmm: skunkworks: I'm still trying to figure out what to do with 5 0ft extensions cords that have no ends on them
08:17 PM andypugh: jymmmm: if they are 0 ft long how do you know you have 5 of them?
08:18 PM XXCoder: it has infinite amount of 0 ft in it
08:18 PM XXCoder: veegee: compressor type is best for dehumid apparently, but also apparently noisy
08:27 PM jymmmm: andypugh: lol five, 50 ft long, But if I'm hording 0ft ext cords, I'm too far gone
08:27 PM XXCoder: :)
08:28 PM andypugh: You could make them into 25 10ft long cords with no ends on them.
08:28 PM XXCoder: can buy plugs for those
08:32 PM jymmmm: I wonder if it's cheaper to buy wall outlets and electrical tape than the proper plugs? Ghetto fabulous ext cords, all 25 of em
08:38 PM Tom_itx: jymmmm, portable generator then you can put power where you need it
08:39 PM XXCoder: zpm yes
08:40 PM XXCoder: erm misremembered name lol
08:40 PM jymmmm: Tom_itx: no more squid cables for me tyvm
08:40 PM XXCoder: got it right actually
10:31 PM _unreal_: found my limit switches finally
10:32 PM _unreal_: got them installed onto the new cnc machine
10:32 PM _unreal_: now I can start soldering limit switch wires up