#linuxcnc Logs

Jun 22 2021

12:22 AM veegee: M35 cobalt steel vertical shear tool on the lathe is giving me 1µm tolerance on a length of 15mm
12:29 AM veegee: That is damn impressive.
12:29 AM veegee: Also proves that the lathe is holding tolerances and the guys I bought it from didn't try to scam me or anything like that
12:29 AM veegee: 150mm*, not 15mm
01:14 AM Deejay: moin
01:21 AM randy: morning
02:31 AM -!- #linuxcnc mode set to +v by ChanServ
04:11 AM Tom_L: morning
04:11 AM tiwake[m]: no
04:11 AM tiwake[m]: time does not exist right now
04:13 AM XXCoder: good. ill stop aging then
04:22 AM tiwake[m]: between 2am and 5am it is neither yesterday, today nor tomorrow
05:03 AM JT-Cave: morning
05:04 AM XXCoder: yo
05:10 AM TurBoss: morninh
05:10 AM TurBoss: * morning
08:52 AM JT-Shop: I guess I should wash the Wing before the ride today
09:29 AM Tom_L: good day for a ride
09:36 AM JT-Shop: tomorrow is too, going to echo bluff state park today
09:36 AM Tom_L: nice
09:36 AM JT-Shop: gotta take advantage of good weather
09:39 AM Tom_L: yeah this cool breeze won't last forever
09:57 AM roycroft: today is assembly day for me - i'll be gluing up the drawers i made yesterday
09:59 AM roycroft: i am thinking about going to the coast later this week, though
09:59 AM roycroft: mainly because 22 degrees is a lot more pleasant than 38 degrees
12:31 PM Tom_L: https://github.com/Libera-Chat/libera-chat.github.io/commit/cf52115
12:31 PM Tom_L: fwiw
02:55 PM norias: Adaika96: hello
03:37 PM Eric__: don't even seem to be able to connect to freenode now. weird
03:48 PM CaptHindsight[m]: whodah thought that they would be so self destructive?
04:02 PM Eric__ is now known as unterhausen
05:00 PM unterhausen: cockroaches will be using the IRC protocol to rule the world after human extinction
05:02 PM Tom_L: maybe they've begun
05:22 PM JT-Shop: nice 200 mile trip today
05:27 PM Tom_L: fun
05:27 PM Tom_L: no cutter showed up today
05:27 PM Tom_L: it's in KC
05:31 PM JT-Shop: hmm I need to check the mail
05:46 PM JT-Shop: Poplar Bluff is going to be a Gigabyte city in 12 months or less... prob nothing out here
07:25 PM Tom_L: JT-Shop, wouldn't that be sumthin
07:51 PM skunkworks: rpi4 running latency for days.. about 70us
07:54 PM Tom_L: on the green machine?
08:00 PM skunkworks: no - just a pi that I had at the house. Was trying the 64bit version someone did on the forum
08:00 PM skunkworks: doesn't seem to be any better or worse than the linuxcnc image.
08:02 PM Tom_L: i see
08:25 PM XXCoder: 70us eh how good is that
08:34 PM XXCoder: ohh handcrafted. looks extremely skilled
08:34 PM XXCoder: https://youtu.be/X2TIM2f9ubI
09:52 PM mrec: is there any pin which can be used for reporting the spindle speed?
09:53 PM mrec: eg. I'm getting the current spindle speed via a command from my microcontroller
09:54 PM mrec: I know there's spindle at speed but that looks rather inaccurate I'd like to know the real speed
09:54 PM mrec: my spindle speed might go down on load since there's an issue with the cheap chinese (and completely epoxied) vfd
09:54 PM Tom_L: you just about need an encoder or some type of feedback
09:55 PM Tom_L: i just did some tuning on mine and got it way better on load
09:56 PM Tom_L: by using encoder feedback to linuxcnc and running a pid on it and what the vfd does itself
09:57 PM Tom_L: look at the parameters on the vfd
09:57 PM mrec: I only interfaced the potentiometer + encoder
09:58 PM Tom_L: so it's manual speed control?
09:58 PM mrec: I control it via a microcontroller, it's a VFD (but with no real interfaces)
09:58 PM mrec: and the pid controller is not reliable
09:59 PM mrec: so I need to be careful when setting up an NC program to not overload anything
09:59 PM Tom_L: i had that problem when i was using the sherline stock motor
09:59 PM mrec: the motor overshoots after the load is gone
10:00 PM Tom_L: i ran water cooling to it for a while
10:00 PM Tom_L: yeah
10:00 PM mrec: the motor board is completely epoxied the manufacturer agreed to send me a non epoxied version of it but they're also looking into the issues which I have reported
10:00 PM Tom_L: you need to hook it up to linuxcnc and work on tuning it
10:00 PM mrec: I would need a different controller for it first
10:00 PM Tom_L: i assume you're running linuxcnc
10:01 PM Tom_L: i'm using a 0-10v analog signal from a mesa card
10:01 PM mrec: yes but the driver is that epoxied pcb here where the onboard pid is not tuned properly
10:02 PM mrec: mine is 0-4V effectively, I'm doing that with a microcontroller connected via usb
10:02 PM mrec: so is there no direct feedback where I could put an RPM value (unless I do something fully custom)?
10:02 PM mrec: feedback pin*
10:03 PM mrec: my controller is counting the pulses
10:05 PM mrec: speed-in maybe?
10:14 PM mrec: I think I got it
10:15 PM mrec: I'll just connect current_speed of my vfd driver with pyvcp.spindle_rpm
10:17 PM Tom_L: net spindle-vel-cmd spindle.0.speed-out => pid.0.command
10:17 PM Tom_L: net spindle-velocity hm2_[HOSTMOT2](BOARD).0.encoder.01.velocity => near.0.in2 scale.0.in spindle.0.speed-in
10:18 PM Tom_L: that's where the encoder ties to the spindle speed in
10:18 PM mrec: I'm only using the parallel port here
10:18 PM Tom_L: mrec, you may need to scale it
10:18 PM Tom_L: ok
10:18 PM mrec: + USB controllers
10:18 PM Tom_L: i display the current rpm as well
10:19 PM mrec: I guess I will build another machine in a few years with better hardware
10:19 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Current_Linuxcnc_Axis_screen.png
10:19 PM mrec: I'm interested in using a lattice FPGA with linuxcnc
10:19 PM Tom_L: digital and analog
10:19 PM Tom_L: why?
10:19 PM mrec: http://linuxcnc.org/docs/html/gui/pyvcp-examples.html#_gs2_rpm_meter_a_id_gs2_rpm_meter_a
10:20 PM mrec: it would be a nice FPGA project
10:20 PM Tom_L: that's what i'm using
10:20 PM Tom_L: along with a digital readout of it
10:20 PM mrec: I've done some FPGA designs in the past
10:20 PM Tom_L: lattice tools aren't free are they?
10:20 PM Tom_L: xilinx are
10:21 PM Tom_L: i've got webpack installed
10:21 PM Tom_L: and did a little with fpga
10:21 PM mrec: for my purpose it was free, they offer some free tools
10:21 PM mrec: but also sell some IP blocks afaik
10:21 PM Tom_L: my config for that display is all in that directory
10:22 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/configs/NEW_MILL_SHOP_2.8.1/display.xml
10:22 PM Tom_L: part of it
10:23 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/configs/NEW_MILL_SHOP_2.8.1/postgui.hal
10:40 PM Tom_L: andypugh, i was searching for a way to get the tool description to display and noticed PR 1032. was that closed and nothing changed on the manualtoolchange.py?
10:41 PM Tom_L: i didn't want it on the tool change but rather on the pyvcp side of the axis screen
11:16 PM veegee: "Similar to NM cables, AC isn’t permitted for use in commercial buildings or residential constructions exceeding three stories."
11:16 PM veegee: Ok so what _IS_ permitted?
11:17 PM veegee: I keep seeing what's not permitted but can't find what IS permitted for > 3 stories
11:39 PM JavaBean: you can't have AirConditioning?? or AlternatingCurrent?