#linuxcnc Logs
Apr 15 2021
#linuxcnc Calendar
12:56 AM Deejay: moin
01:42 AM veegee: https://www.youtube.com/watch?v=qsvpU7G5IJg
01:42 AM veegee: I can't believe he actually did it
01:44 AM veegee: It's shitty, but it actually sustained its combustion for 10 seconds
02:06 AM veegee: Cool way to charge your cordless drill battery while it's still in the tool: run it at full speed and inject compressed air into the impeller to turn the motor into a generator lol
04:22 AM Tom_L: morning
05:31 AM JT-Cave: morning
06:08 AM miss0r: mornin'
09:26 AM JT-Shop: wow Stuart is back!
11:17 AM Connor: So, anyone have an ideas on adding a Reboot / Shutdown button on a panel in Axis?
11:31 AM -!- #linuxcnc mode set to +v by ChanServ
11:31 AM cradek: it's important to exit linuxcnc before shutting down or rebooting the machine, so this is not a good idea
11:31 AM cradek: on my touchscreen machines I exit and then use the shutdown button on the toolbar
11:31 AM Connor: What is that?
11:31 AM cradek: the status bar tool bar thing, like where the clock is etc, I don't know what it's called nowadays
11:31 AM cradek: the place programs minimize to
11:31 AM Connor: Yea, sorry.. I know. I was asking why is it important to exit linuxcnc. ?
11:31 AM cradek: so it writes out its status files
11:31 AM cradek: the var file and (in some configs) tool table are written at exit
11:31 AM cradek: there might be others too
11:31 AM Connor: So, the buttons would need to close LInuxCNC and then shutdown / reboot.
11:33 AM Connor: Thanks anyway.
11:41 AM pcw_home: Could you have a script that does a shutdown when you exit LinuxCNC?
11:41 AM Connor: That might be TOO locked down. I may need them to exit out so I can walk them through something on the desktop.
11:42 AM pcw_home: The script could give you options
11:42 AM Connor: I guess the could unplug the ethernet to the mesa card and reboot it and it would cause linuxcnc to debug..
11:43 AM Connor: Is there a call that can be sent to LCNC to cause it to shutdown? a Signal?
11:44 AM Connor: Could have the buttons drop a semaphore file, and write a cron to check for it every few seconds.. and if it finds it, shuts down linuxcnc, delete the file, the reboot/shutdown with bash command.
11:55 AM JT-Shop: shutdown.hal?
12:34 PM Connor: PVC or Silicon wire in your CNC enclosure? Which one?
12:41 PM Rab: Teflon!
12:45 PM Tom_L: pvc should be fine
12:48 PM JT-Shop: MTW
01:11 PM Connor: God it's been too long since I've done one of these.. Pul+/Pul- Direct with each other.. O do I need a 5v/Gnd ?
01:28 PM drdoc: morning, all
01:30 PM drdoc: Connor: running Axis fullscreen, can you still pull up a terminal?
01:31 PM drdoc: Rab: ping
01:47 PM drdoc: I've rendered "Sunny | Customer Service" on Amazon Chat speechless
01:48 PM drdoc: typing whole words, being polite, and being right messes them right up.
01:53 PM CaptHindsight: IRC, Matrix, Discord, facebook... trying to keep track of discussions. It has gotten so fragmented
01:59 PM Tom_L: sew them all back together
02:05 PM CaptHindsight: it's software, so inherently broken
02:07 PM drdoc: All software is evil
02:08 PM drdoc: some is more evil than the rest
02:17 PM drdoc: https://www.mile-x.com/baldor-ab248-abrasive-belt
02:17 PM drdoc: $40 for a 2x48 grinder belt????
02:24 PM gloops: demand is up
02:25 PM CaptHindsight: copper wire is also up
02:25 PM CaptHindsight: the building contractors said lots of their other materials are also way up now
02:25 PM gloops: timber x3
02:25 PM CaptHindsight: electrical, plumbing, etc
02:26 PM CaptHindsight: I haven't priced any aluminum or steel lately
02:29 PM CaptHindsight: aluminum is up by 50% from this time last year
02:29 PM drdoc: gloops: I could buy a dozen Norton zirconium belts for that
02:30 PM CaptHindsight: https://tradingeconomics.com/commodity/aluminum
02:30 PM miss0r: I thought it was getting expensive
02:30 PM drdoc: aluminum is just nuts
02:30 PM drdoc: it's beginning to affect even soft drink prices
02:31 PM miss0r: that is where I draw the line!
02:31 PM miss0r: I do like my softdrinks
02:31 PM CaptHindsight: https://tradingeconomics.com/commodity/steel
02:32 PM CaptHindsight: sugar is up but corn is down, so it depends on your soda
02:32 PM drdoc: lol
02:33 PM gloops: so long as barley stays reasonable
02:36 PM CaptHindsight: drdoc: I make my own belts from bulk stock
02:37 PM gloops: things go on like this ill be making my own sandpaper
02:37 PM drdoc: interesting
02:37 PM CaptHindsight: or buy longer ones and cut to size https://www.combatabrasives.com/products/2-x-72-sanding-belt?variant=15338600366146
02:37 PM gloops: including making the paper
02:37 PM drdoc: how do you splice them?
02:38 PM CaptHindsight: https://www.emisupply.com/catalog/article_info.php?articles_id=13&%3CosCsid%3E
02:38 PM Connor: drdoc No. I can remote into the machine though. :)
02:38 PM CaptHindsight: https://www.youtube.com/watch?v=qesLxgVmPzQ
02:39 PM CaptHindsight: Make Your Own Sanding Belts ^^
02:39 PM drdoc: that's interesting
02:39 PM drdoc: I have a 2x72 grizzly
02:40 PM CaptHindsight: HF has it in bulk
02:41 PM drdoc: has which?
02:42 PM CaptHindsight: https://www.harborfreight.com/2-34-in-x-25-ft-240-grit-sandpaper-roll-63332.html
02:42 PM drdoc: ah, ok
02:43 PM gloops: emery cloth yesterday was £1 a sheet 9x11, thats up
02:43 PM CaptHindsight: but 2 x 72 is only $8.43 here https://www.empireabrasives.com/2-inch-x-72-inch-ceramic-sanding-belt/
02:44 PM CaptHindsight: heh 10 packs on Amazon for $14
02:44 PM drdoc: I know. I haven't found anythin g better than Norton, and anything finer than 60 grit is usually less than $2/belt
02:45 PM CaptHindsight: I have a custom belt sander so I have to make my own belts
02:45 PM drdoc: hogging grits and very fine grits get expensive
02:45 PM drdoc: I keep saying I'm going to build a 4-wheel 2x72, but since I quit smithing I don't use it that much
02:46 PM gloops: https://www.ebay.co.uk/itm/184426991421? 6 for £15
02:46 PM drdoc: otoh, since I got the Grizzly I haven't put a stone wheel on the bench grinders. Period
02:47 PM gloops: ceramic more than double that
02:47 PM drdoc: I usually buy from truegrit.com
02:47 PM drdoc: mostly because the name is so silly
02:48 PM drdoc: gloops: the problem with generic belts is consistency more than longevity
02:48 PM drdoc: one 40 grit chunk on an 80-grit belt will wreak havoc on your finish
02:49 PM drdoc: one 400g chunk on a 600g is even worse
02:49 PM gloops: or you can get 50metres of emery cloth for £30 https://www.ebay.co.uk/itm/Emery-Cloth-Roll-Very-fine-Very-coarse-Aluminium-Oxide-1-Metre-50-Metres/264495118084?
02:49 PM gloops: drdoc i dont use a belt sander so not really up on it
02:50 PM gloops: grinding knives or something like that?
02:50 PM drdoc: pretty-much anything that I want smooth & pretty
02:51 PM drdoc: sometimes that's 220g and sometimes 2400g or even finer
02:51 PM gloops: thats like a mirror finish
02:53 PM drdoc: yup
02:53 PM drdoc: https://www.facebook.com/media/set/?set=a.1238420675078&type=3
02:54 PM drdoc: that opal was a piece of a bigger, broken stone
02:54 PM drdoc: the knife started as a chunk of 1x1/4" 1084
02:54 PM drdoc: and a cow's leg bone
02:55 PM gloops: very nice
02:55 PM drdoc: thank you
02:55 PM gloops: was going to ask if you'd made them or restored them
02:55 PM drdoc: "yes"
02:56 PM drdoc: :-)
02:57 PM drdoc: my great grandfather was a blacksmith, and I started making jewelry when I was 12
02:59 PM drdoc: went to the Mint with my folks & saw the cutout dime & quarters in the curiio shop
02:59 PM drdoc: https://www.etsy.com/listing/573577619/mercury-dime-silver-cut-coin-pendant
02:59 PM gloops: so its in your blood - i was thinking of doing a bit of wooden jewellery but never got round to it
02:59 PM drdoc: pestered my old man till he bought me a set of jewelers' files, drilled holes in a quarter and filed it out
03:00 PM drdoc: I think it's exactly that
03:01 PM drdoc: I was at a pagan meet once and some lady asked me what was my "spiritual framework"
03:01 PM drdoc: I told her "I'm a blacksmith."
03:01 PM drdoc: she never quite grasped that I was perfectly serious.
03:02 PM drdoc: and that it really was the answer to her question
03:02 PM gloops: well there have been Gods who worked the anvil - Thor springs to mind
03:03 PM gloops: it would certainly have been a spiritual/divine craft in the early days of metal
03:03 PM drdoc: more than that - blacksmiths have always been set apart as different
03:03 PM drdoc: even in more modern times.
03:03 PM drdoc: probably because we stink
03:03 PM drdoc: :-D
03:05 PM drdoc: there's something divine about seeing a tool take shape under your hammer.
03:06 PM drdoc: I don't mean that it's godlike - more like getting to touch a god
03:11 PM gloops: yeah, its an elemental thing with metals, the fire, water all that
04:22 PM _unreal_: hello
04:22 PM _unreal_: olimexino-stm32 I ordered one of these
04:23 PM _unreal_: drop in replacement for an arduino
04:23 PM _unreal_: much stonger
04:23 PM _unreal_: stronger. going to be my arduino laser etcher controller upgrade
04:44 PM CaptHindsight: Which names of software apps are appealing to avaricious people?
04:50 PM CaptHindsight: just change the name every few years to keep up with the marketspeak
04:50 PM CaptHindsight: Cloud CNC, Edge CNC, AI CNC etc
04:53 PM _unreal_: CaptHindsight, lcnc
04:53 PM _unreal_: :)
04:53 PM XXCoder: or shorten it to LCNC
04:54 PM _unreal_: copy cat
04:54 PM _unreal_: hum
04:54 PM _unreal_: nogoddamnidea hasnt been talking much
04:54 PM _unreal_: think he gave up on his CNC machine?
04:55 PM _unreal_: last I knew he was still having issues with solving the wiring
04:55 PM _unreal_: and and control
06:12 PM unterhaus_: I don't think EMC was a particularly good name for a cnc
06:13 PM unterhaus_: I like LCNC too
06:14 PM unterhaus_: EMC was dying when they sent that cease and desist letter
06:30 PM roycroft: hello, folks
06:30 PM roycroft: first, i'm fine with the name change and am quite familiar with the history of linuxcnc/emc
06:30 PM roycroft: but naming it linuxcnc pretty much ties it to linux
06:31 PM XXCoder: it'll be always used in linux os but yeah thats why I thought LCNC is fine
06:31 PM roycroft: that was my only thought on the matter when the name was changed
06:31 PM XXCoder: still linux, but not on face
06:31 PM roycroft: you don't know if it will always be linux-based
06:31 PM roycroft: it looks like that now
06:32 PM roycroft: but 10 years from now there may be something better and more suited to real-time apps
06:32 PM roycroft: anyway
06:32 PM roycroft: that's all i have to say on that
06:32 PM roycroft: but i am confused now
06:32 PM roycroft: which is not an unusual state of affairs for me, but i was surprised to be confused by this
06:33 PM roycroft: my broach and collar have arrived
06:33 PM roycroft: and i'm ready to cut my keyway
06:34 PM roycroft: i thought the procedure would be fairly straightforward
06:34 PM roycroft: insert collar, insert broach, which will fit snugly but will fit until it reached the first tooth
06:35 PM XXCoder: my fancy TC nozzle just arrived
06:35 PM roycroft: push down on broach
06:35 PM roycroft: keyway is produced
06:35 PM roycroft: however, the broach does not seem to fit in the collar
06:35 PM XXCoder: wow! https://www.sciencemag.org/news/2021/04/glass-molded-plastic-could-usher-new-era-complex-shapes
06:35 PM roycroft: and i confirmed that i purchased the correct items
06:35 PM roycroft: the collar fits nicely in the bore
06:36 PM roycroft: and i think if i push on the broach it will go down
06:36 PM roycroft: but i thought it should fit better
06:36 PM roycroft: roycroft.us/Broach
06:37 PM roycroft: the bore is sadly about 0.006" oversize
06:37 PM roycroft: i wanted to make it tighter than that but that's how it turned out
06:37 PM roycroft: i should think that would make it easier to insert the broach, though
06:38 PM -!- #linuxcnc mode set to +v by ChanServ
06:38 PM roycroft: so am i supposed to need to push on it just to start inserting it?
06:39 PM XXCoder: roy hm thats odd. whats bore +- tol anyway
06:39 PM drdoc: I would, relatively gently
06:39 PM XXCoder: man that inject mold glass rocked my world in a way
06:40 PM XXCoder: can make very complex shapes in it for applications in hyper-corrosive envorment
06:40 PM roycroft: it does no fit in my arbor press, as i anticipated
06:40 PM -!- #linuxcnc mode set to +v by ChanServ
06:40 PM roycroft: so i have to use a 12 ton hydraulic press
06:41 PM roycroft: i can be somewhat gentle, but it won't be as controlled as i'd like
06:41 PM drdoc: yeah, then I might not.
06:41 PM roycroft: when i watch videos on broaching, folks insert the broach into the bushing, and it goes down easily for a while before the teeth grab
06:41 PM roycroft: the good thing is that this is cast iron i'm broaching
06:42 PM roycroft: so it will be pretty easy to cut
06:42 PM drdoc: Every keyway I ever cut, the broach didn't start cutting till a few teeth in
06:42 PM roycroft: that's what i expected
06:42 PM roycroft: so i don't understand why this isn't setting up like that
06:42 PM roycroft: the broach says it nees a b collar
06:42 PM roycroft: i got a b collar
06:42 PM roycroft: b = b as far as i know
06:43 PM roycroft: i might try tapping on the broach very gently with a light hammer to see if it wants to start
06:43 PM roycroft: it is so close to fitting - only a few thousandths
06:44 PM * roycroft decides to very gently tap it to see what happens
06:44 PM roycroft: thank you for confirming that my expectations were correct
06:44 PM -!- #linuxcnc mode set to +v by ChanServ
06:44 PM roycroft: now to figure out why reality does not meet expectations
06:45 PM roycroft: for the hundred millionth time :)
06:45 PM XXCoder: :)
06:46 PM -!- #linuxcnc mode set to +v by ChanServ
07:11 PM roycroft: well, i succeeded
07:11 PM roycroft: the keyway is a bit deeper than i think it should be
07:11 PM roycroft: i haven't measured, but it looks a bit deeper, which i'd expect, given the problem with the broach
07:14 PM roycroft: https://roycroft.us/Broach/Handwheel1.jpeg
07:14 PM roycroft: https://roycroft.us/Broach/Handwheel2.jpeg
07:14 PM roycroft: i'll have to pursue this with the vendor to see if we can determine what is wrong
07:16 PM roycroft: this keyway will work fine - it's very low torque, and a keymay may not even be necessary
07:16 PM roycroft: but for future keyways i want it to work better
07:22 PM Connor: Don't most broach's use shims?
07:22 PM Connor: to go deeper?
07:23 PM roycroft: yes, and the broach comes with the correct number of shims for the size
07:23 PM roycroft: this one uses one shim
07:24 PM roycroft: and on the first pass it was definitely not deep enough
07:25 PM roycroft: i also had to tap it in to get it started on the second go, just like on the first go
07:25 PM roycroft: which i don't think is right
07:26 PM roycroft: oh well, it's done now and will work fine
07:26 PM roycroft: i need to go clean the handwheel, blue it, and oil it so i can install it
08:00 PM Tom_L: shouldn't. the end of mine started and i pressed from there
08:04 PM CaptHindsight: coat the shaft with some loctite and assemble, call it done
08:07 PM roycroft: yeah, there is something wrong with what i got
08:08 PM roycroft: i don't know what the difference is between b and b1 broaches/collars, but i made sure that both the broach and collar i bought were "b", and not "b1"
08:08 PM roycroft: they are from different manufacturers
08:08 PM roycroft: because that's all i could find
08:09 PM roycroft: but one would think that the sizes would be standard and interchangeable
08:09 PM roycroft: that's what i'll pursue with the vendor tomorrow
08:09 PM -!- #linuxcnc mode set to +v by ChanServ
08:09 PM _unreal_: so I brought my laser etcher into the canvas company
08:09 PM _unreal_: they are going to make a shell for it
08:12 PM roycroft: does my keyway look a bit too deep to you, tom_l?
08:13 PM * roycroft will go measure it after dinner
08:14 PM roycroft: in the worst case i could take some m5 square stock and machine 1mm off one side
08:27 PM Tom_L: i think it looks pretty close
08:27 PM Tom_L: at least from the backside view
08:28 PM roycroft: maybe it's fine
08:31 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/rotary/Broach/Test_Keyway9.jpg
08:31 PM Tom_L: no worse than that
08:31 PM Tom_L: and that turned out fine i think
08:37 PM roycroft: the key fits, and that's what is most important
08:37 PM Tom_L: jup
09:05 PM CaptHindsight: Valen: using a Mesa FPGA or all in software?
09:06 PM Valen: FPGA
09:06 PM CaptHindsight: in the software case they are not buffered
09:07 PM CaptHindsight: same for the FPGA, I'll let PCW give you the details on how the FPGA does it
09:08 PM CaptHindsight: stepgen in HW
09:08 PM CaptHindsight: the USB CNC controllers have the buffering
09:10 PM Valen: Are there any of those for lcnc?
09:13 PM CaptHindsight: there was some Linuxcnc to arduino thing I recall
09:13 PM CaptHindsight: forhget if it used USB or not, let me check
09:16 PM CaptHindsight: the problem with USB is losing all the timing
09:17 PM CaptHindsight: for open loop stepping you could transfer step times over USB and have an FPGA or microcontroller resync the steps
09:19 PM CaptHindsight: not sure how fast you could step that way until the XYZ gets jerky
09:20 PM CaptHindsight: the spindle would be spinning and the motion might pause at times
09:20 PM CaptHindsight: it would accell and decell abruptly vs smoothly if the buffer runs out
09:21 PM CaptHindsight: https://emc2arduino.wordpress.com/faq-2/faq-hal2arduino/
09:22 PM CaptHindsight: Valen: what would you like to do?
09:22 PM Valen: I was just curious how it all worked really
09:22 PM Valen: One of those talking to people and you realise theres some magic you don't know that you depend on
09:22 PM CaptHindsight: i was just looking at the stepgen code
09:23 PM CaptHindsight: https://forum.linuxcnc.org/18-computer/39037-linuxcnc-orange-pi?start=100#205039
09:23 PM mrec: does a glass-scale have some start marker?
09:24 PM Valen: The ones I have used have an index pulse every 100mm or so if memory serves
09:24 PM Valen: (might be some other distance)
09:24 PM CaptHindsight: tomp just wrote that up when working on a driver for software stepping using an integrated micro-controller in an ARM SOC
09:24 PM Valen: I used them for homing by putting some marks on the machine, then I'd jog it to the marks, hit home and it'd probe to the index pulses, had to be in the right place to start so it'd hit the right index pulse
09:25 PM -!- #linuxcnc mode set to +v by ChanServ
09:25 PM mrec: I have some magnetic scales installed at the moment, but I'd be interested in accurate homing.
09:26 PM mrec: for rough homing hall effect sensors, and then it should search the index mark but I think the magnetic scales I have don't have that
09:26 PM CaptHindsight: Valen: Mach uses USB and generates all the steps on the machine side of the USB connection vs the PC
09:27 PM Valen: I haven't heard of the magnetic ones having an index
09:28 PM CaptHindsight: https://github.com/scottalford75/Remora puts the stepgen in a microcontroller connected to Linuxcnc via SPI
09:29 PM CaptHindsight: so it's like a Mesa card with a microcontroller vs a FPGA
09:29 PM CaptHindsight: https://remora-docs.readthedocs.io/en/latest/
09:31 PM CaptHindsight: https://www.youtube.com/watch?v=1rctCsUGnX8&t=165s
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09:36 PM pcw_home: Valen: Our FPGA stepgen is basically just a digitally programmed oscillator (updated at LinuxCNCs servo thread rate which is typically 1 KHz)
09:37 PM Valen: Does that mean the position isn't actually deterministic given jitter in the servo thread?
09:37 PM pcw_home: latency only effects the velocity update time
09:39 PM pcw_home: The position is deterministic since the actual step count (in 1/65536th of a step) is fed back
09:40 PM pcw_home: a PID loop correct for minor errors cause by hardware/LinuxCNC time base differences, velocity setting quantization, read/write timing jitter etc
09:41 PM Valen: Ahh that's the trick, thanks for that
09:41 PM pcw_home: stepgen fidelity is typically in the range of 100ths of a step
09:42 PM CaptHindsight: in machine movement that would be well below 1um
09:43 PM CaptHindsight: unless you have very big steps
09:43 PM Valen: That's a pretty neat solution, better than anything that drifted through my head. I don't suppose you know off hand if the smoothstepper and the like work the same way? Just chatting with a bunch of CNC nerds at the moment ;-)
09:45 PM CaptHindsight: smoothstepper was all open loop until recently
09:45 PM Valen: with the same "update at servo rate" style scheme?
09:46 PM pcw_home: No idea what they do. We also have a DPLL to retime the position sampling to be less affected by servo thread jitter
09:46 PM CaptHindsight: works like GRBL on a duino
09:46 PM Valen: so smooth stepper now does the motion planning?
09:47 PM pcw_home: smooth stepper is buffered so probably has at least a simple interpolator
09:47 PM CaptHindsight: trjectory planning is done on the PC
09:47 PM pcw_home: and storage of many motion segments
09:48 PM Valen: That'd need special handling for probe and limit I'm guessing?
09:48 PM Valen: probe/home etc
09:49 PM pcw_home: since its not real time it has to store at least a few hundred ms of motion
09:49 PM Valen: and no spindle synchronised motion?
09:49 PM pcw_home: probe and home and spindle synced motion etc need to be done in the smooth stepper
09:50 PM CaptHindsight: there was some news on this but not working really well yet IIRC
09:52 PM CaptHindsight: https://www.cnc4pc.com/blog/post/project-semi-rigid-tapping-with-mach-3
09:52 PM CaptHindsight: i think skunkworks had a "discussion" with them about this
09:54 PM CaptHindsight: https://youtu.be/zW9hgwDN9hY?t=32
10:00 PM Tom_itx is now known as Tom_L
10:25 PM -!- #linuxcnc mode set to +v by ChanServ
10:37 PM CaptHindsight: Valen: I don't see why someone could not write a CNC app that uses USB only for the GUI or to transfer programs to a controller
10:38 PM CaptHindsight: there are some crazy powerful microcontrollers now
10:39 PM CaptHindsight: https://www.st.com/content/st_com/en/products/microcontrollers-microprocessors/stm32-arm-cortex-mpus/stm32mp1-series/stm32mp157/stm32mp157d.html
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