#linuxcnc Logs
Sep 22 2025
#linuxcnc Calendar
12:58 AM -!- #linuxcnc mode set to +v by ChanServ
01:19 AM jpa-: Guest46: the motion core deals with coordinates (XYZ for location, ABC for rotation, UVW for special purposes)
01:19 AM jpa-: Guest46: then there is a kinematics module that converts these to join positions (motor commands) to actually get the machine to the commanded location
03:17 AM -!- #linuxcnc mode set to +v by ChanServ
04:19 AM Tom_itx: morning
04:19 AM Tom_itx is now known as Tom_L
05:05 AM Deejay: hi
06:30 AM -!- #linuxcnc mode set to +v by ChanServ
07:24 AM lcnc-relay: <ebe_lyn@> i noticed a weird behavoir in qtdragon. i have backlash comp enabled, and in HAL my x-pos-fb is the linear encoder position. the DRO in qtdragon displays the encoder postion, but upon each direction change it adds/removes the backlash to the displayed value. i can confirm this by unplugging the encoder, also in halshow the value of x-pos-fb isn't changing. anyone seen something like this?
07:27 AM JT-Cave: no one uses qtdragon here that I know of
07:28 AM lcnc-relay: <ebe_lyn@> whats the preferred interface? probe basic?
07:42 AM JT-Cave: Flex GUI
07:54 AM lcnc-relay: <ebe_lyn@> thanks, i'll check and see if it has the same issue.
07:59 AM lcnc-relay: <rs> ebe_lyn@: that may be just an artifact. so suppose you are going from 10mm to 0mm and then reverse and have 1mm backlash (just to give some numbers), then the machine has to travel +1mm to be at 0mm again.
08:00 AM lcnc-relay: <rs> may well be that display will jump from 0mm to -1mm as soon as you reverse direction
08:02 AM lcnc-relay: <rs> fwiw it shouldnt depend on the GUI used
08:03 AM lcnc-relay: <ebe_lyn@> i'm hoping flex gui will allow me to configure the DRO to display the true table position, rather than that commanded pos. it's a manual converted mill so i do a lot of manual operations with jogging that rely on the DRO display to be accurate to the table
08:05 AM rdtsc-w: using FlexGUI, was able to create a DRO + "tool radius" display so can "see" where the edges of any arbitrarily-entered diameter tools lie
08:07 AM JT-Cave: wow hal leds now work! now to polish up the docs
08:09 AM rdtsc-w: nice :)
08:09 AM JT-Cave: https://pasteboard.co/uUWlPdyzHWK9.png
08:10 AM JT-Cave: https://pasteboard.co/ylwHf522CgcR.png
08:10 AM JT-Cave: gotta polish up the location of the gradient maybe put it in the upper right corner or something
08:13 AM lcnc-relay: <rs> ebe_lyn@: encoder will give number of turns + angle of spindle but not table position. you could mount glass scales for accurate table pos.
08:13 AM lcnc-relay: <ebe_lyn@> thats what i meant by linear encoder, they are glass scales
08:14 AM lcnc-relay: <rs> don't think you need backlash comp for those
08:18 AM lcnc-relay: <ebe_lyn@> eventually yes, im in the process of setting it up for the first time and i wanted to get it running okay in open loop mode first
08:19 AM * JT-Cave waits for Tom_L to break it
08:21 AM lcnc-relay: <rs> https://www.linuxcnc.org/docs/html/code/code-notes.html#_block_diagrams_and_data_flow
08:44 AM -!- #linuxcnc mode set to +v by ChanServ
08:50 AM Gothia1 is now known as Gothia
08:57 AM lcnc-relay: <lesliet@> _head in hands_ gawds, I have so much to learn
09:09 AM rdtsc-w: how does one eat an elephant? one bite at a time
09:24 AM lcnc-relay: <lesliet@> but... I'm a vegetarian... _eyeblink_
09:24 AM lcnc-relay: <lesliet@> watching lots of videos, reading manuals until loss of consciousness
09:25 AM lcnc-relay: <lesliet@> gonna take me a little bit to get the basic machine fixed up to a point where I need to worry about software
09:26 AM lcnc-relay: <lesliet@> or not
09:27 AM lcnc-relay: <lesliet@> hmm, guess it doesn't like imgur?
10:24 AM JT-Shop: what is an it?
12:18 PM lcnc-relay: <lesliet@> I stuck a screenshot in #meta
12:20 PM xxcoder: irc people cant see that :)
12:22 PM lcnc-relay: <lesliet@> https://imgur.com/gallery/new-project-bridgeport-boss-v2e4-from-1982-xxOHbSP
12:22 PM lcnc-relay: <lesliet@> woo, it works!
12:22 PM lcnc-relay: <lesliet@> so, having text in the same line breaks it?
12:22 PM xxcoder: yeah. I guess some combo of words got last one tagged as spam
12:22 PM xxcoder: dont know why tho lol
12:23 PM lcnc-relay: <lesliet@> having links is probably better than just posting a photodump anyway, I guess
12:23 PM Tom_L: my friend had a boss 5
12:23 PM lcnc-relay: <lesliet@> read it if you want, or pass if not interesting
12:23 PM xxcoder: already reading ;)
12:24 PM lcnc-relay: <lesliet@> I think this one is a boss 8 or 9
12:24 PM lcnc-relay: <lesliet@> so dc servos, rather than steppers
12:24 PM lcnc-relay: <lesliet@> although those early steppers were kind of cool looking, with the big cast iron fins
12:24 PM xxcoder: I see it come with some forbidden nutella
12:24 PM Tom_L: we hooked into the old tape reader via 20ma loop
12:25 PM Tom_L: i had the manuals but gave them to archivist
12:25 PM Tom_L: then he left
12:26 PM lcnc-relay: <lesliet@> I "kind of" have a manual, there's one circulating for download that's about 1986
12:26 PM lcnc-relay: <lesliet@> the mechanicals seem to largely stay the same over a lot of these models, but I expect the electrical prints changed a lot
12:27 PM xxcoder: probably cheaper to upgrade elctrics over molds
12:27 PM Tom_L: it looks similar
12:27 PM lcnc-relay: <lesliet@> and people want new features
12:27 PM xxcoder: I wonder how archivist is doing
12:30 PM lcnc-relay: <lesliet@> Tom_L: not sure if mine came with a tape reader originally, but if it did, it was already gone when I got it. There's an rs232 dongle, so I expect they were drip feeding it
12:31 PM Tom_L: that's what we did
12:31 PM xxcoder: many was retrofitted with computer that pretends to be tape machine
12:31 PM Tom_L: he didn't keep it that long before he got some new bigger machines
12:31 PM lcnc-relay: <lesliet@> cheap vfd, and lots of broken mechanical speed control stuff on the head, which I'm working on.
12:31 PM xxcoder: my last job, they had computer that emulates many of machines tapes or disk drives and uses ethernet networking
12:32 PM xxcoder: old fadal used to have tape machine but it was connected via networking to "tape machine"
12:32 PM lcnc-relay: <lesliet@> we'll see how useful it is for me, but it seems like a good size for my shop. Lots more travel than the pcnc440, and 2hp for the spindle
12:32 PM Tom_L: just slow and manual toolchange
12:33 PM Tom_L: we preset the tools in holders
12:33 PM lcnc-relay: <lesliet@> yeah, the manual toolchange isn't great, but my 440 is the same
12:33 PM lcnc-relay: <lesliet@> you can get an atc for the 440 but it's crazy expensive
12:34 PM lcnc-relay: <lesliet@> this one has a KwikSwitch200 spindle, and came with a handful of toolholders. Need more of the collet holders, though
12:34 PM lcnc-relay: <lesliet@> but they're not bad, used on e-bay, about $50 each
12:35 PM lcnc-relay: <lesliet@> unfortunately it's DA collets, so I'll need a set of those, too. In addition to all my other collet systems
01:10 PM lcnc-relay: <skunkworks8841@> How do you like your 440?
01:11 PM lcnc-relay: <skunkworks8841@> that electrical box 'almost' looks like it has a mesa card in it.
01:13 PM lcnc-relay: <skunkworks8841@> looks like you have 3 drives.. Hint hint
01:13 PM lcnc-relay: <skunkworks8841@> I think they run at like 10khz - so they are annoying..
01:43 PM Tom_L: flex leds work now
01:43 PM Tom_L: http://tom-itx.no-ip.biz:443/~webpage/cnc/JT-SHOP/flexgui/LED_Test.mp4
01:45 PM xxcoder: thats cool
02:53 PM lcnc-relay: <lucid.nonsense@> Anyone good examples of diy turret mill tool changers? YouTube search being deliberately obtuse in my experience
02:53 PM lcnc-relay: <lucid.nonsense@> Same for web
02:54 PM xxcoder: more and more sites show wht they think you want
02:54 PM lcnc-relay: <lucid.nonsense@> Or what they want, we're the product
02:55 PM xxcoder: indeed
03:18 PM Tom_L: https://forum.linuxcnc.org/26-turning/29289-an-open-source-emco-120p-lathe-tool-turret-control
03:18 PM Tom_L: https://forum.linuxcnc.org/49-basic-configuration/33351-lathe-tool-changer-turret-dc-motor-based
03:18 PM Tom_L: lathe
03:20 PM lcnc-relay: <lucid.nonsense@> Tom_L: Cool, thanks Tom
03:21 PM lcnc-relay: <lucid.nonsense@> I like the taper pin idea
03:25 PM lcnc-relay: <ebe_lyn@> i like flexui, it seems keyboard jogging only allows moving one axis at a time. is that a setting?
03:25 PM Tom_L: i don't think you can in axis either
03:25 PM Tom_L: that sounds dangerous
03:26 PM Tom_L: even my pendant is single axis jogging
03:26 PM Tom_L: you can home multiple axis
03:27 PM lcnc-relay: <ebe_lyn@> axis and qtdragon both allowed it. was wondering if it was a limitation of the program or a safety thing like you said
03:27 PM Tom_L: i don't think axis does
03:27 PM Tom_L: i haven't tried to
03:28 PM Tom_L: holding 2 buttons at the same time?
03:28 PM lcnc-relay: <ebe_lyn@> yeah, moving x and y with up and left arrow to jog to the vise from home
03:28 PM lcnc-relay: <ebe_lyn@> could just use a command
03:28 PM Tom_L: i think that's asking for trouble
03:28 PM Tom_L: i have a button for that
03:29 PM lcnc-relay: <ebe_lyn@> dont see how its any different than a g0 move with x and y coords
03:30 PM lcnc-relay: <ebe_lyn@> / less safe but i am a newb
03:30 PM Tom_L: if you look on the led video i posted above you can see i have an XY button and XYZ
03:30 PM Tom_L: to send it to G54 home
03:31 PM Tom_L: i didn't see a png so: http://tom-itx.no-ip.biz:443/~webpage/cnc/JT-SHOP/flexgui/LED_Test.mp4
03:32 PM Tom_L: you can assign any coord to the buttons you like
03:33 PM lcnc-relay: <lucid.nonsense@> Tom_L: Er du nork?
03:34 PM lcnc-relay: <lucid.nonsense@> Lol norsk
03:34 PM Tom_L: nein
03:35 PM lcnc-relay: <lucid.nonsense@> Ok
03:35 PM lcnc-relay: <lucid.nonsense@> Ah, sorry tired, thought the domain ended in .no
03:41 PM lcnc-relay: <lucid.nonsense@> With the tool changer, I'm most interested in the mechanical design, I suppose an absolute encoder would make things a lot easier
03:42 PM lcnc-relay: <lucid.nonsense@> For a mill at least
03:42 PM Tom_L: carousel?
03:43 PM lcnc-relay: <lucid.nonsense@> Yeah
03:43 PM Tom_L: slots and a beam interrupt
03:43 PM Tom_L: pins & hall sensor
03:43 PM Tom_L: encoder
03:44 PM lcnc-relay: <lucid.nonsense@> Ok thanks, the osram absolute encoders are very cheap though, probably easier than a hall sensor?
03:45 PM Tom_L: using a position locking pin?
03:45 PM lcnc-relay: <lucid.nonsense@> Yeah think that might be good as a failsafe
03:46 PM lcnc-relay: <lucid.nonsense@> Biggest challenge might be the threaded 40 taper spindle
03:46 PM lcnc-relay: <lucid.nonsense@> Pneumatic drawbar
03:46 PM lcnc-relay: <lucid.nonsense@> Unless I do a Pugh drawbar conversion
03:47 PM Tom_L: swing arm
03:47 PM Tom_L: one gets the old tool, the other half gets the new one
03:48 PM Tom_L: you keep track of your pockets in that case
03:48 PM lcnc-relay: <lucid.nonsense@> Yeah, but I have to verify that the tool is threaded fully
03:48 PM lcnc-relay: <lucid.nonsense@> Maybe a limit switch type of thing on the drawbar
03:50 PM lcnc-relay: <lucid.nonsense@> It's basically a pneumatic ratchet, sure you're familiar
04:22 PM lcnc-relay: <roguish> alucid.nonsense@ be careful with that air ratchet system..... you really don't want to throw a tool.
04:48 PM lcnc-relay: <lucid.nonsense@> Yeah, hence the need for a verification system
06:01 PM lcnc-relay: <lesliet@> skunkworks8841@: The 440 is a great beginner cnc. Hard to crash it hard enough to damage anything but tooling. It's a bit limited on power and on work envelope, but it will cut steel and make useful parts.
06:02 PM Unterhaus_ is now known as Unterhausen
06:02 PM lcnc-relay: <lesliet@> Tormach charges premium prices for add-ons like an atc, and a 4th axis, but it's also designed to work out of the box, with no coding
06:02 PM Unterhausen: why does lcnc rely on part of midi port?
06:02 PM lcnc-relay: <skunkworks8841@> I have a prototype 440.. I like it
06:03 PM lcnc-relay: <lesliet@> I'm thinking I'll keep it, even after the big mill is up
06:04 PM lcnc-relay: <lesliet@> although at some point, I may jump in and see if I can figure out how to get a bit more power on the spindle.
06:04 PM xxcoder: frankly if I had choice of 440 or office mill haas, I'd pick 440
06:05 PM lcnc-relay: <lesliet@> I have another friend in a machine shop that absolutely hates Haas. Says they always break, everywhere he's worked
06:05 PM lcnc-relay: <skunkworks8841@> I am using a stmbl drive to run the spindle..
06:05 PM xxcoder: haas: in least its not hurco
06:06 PM lcnc-relay: <lesliet@> When I worked in a machine shop ( I fixed machines, was not an operator) the Haas machines weren't the ones that broke most often
06:06 PM lcnc-relay: <lesliet@> we had some older smaller Cincinnati CNC lathes, and they were just tired.
06:09 PM lcnc-relay: <lesliet@> skunkworks8841@: that's cool, I see it does encoders, too. Would be awesome to be able to run rigid tapping
06:12 PM lcnc-relay: <skunkworks8841@> https://youtu.be/F7QulGiMt20?si=tMUUPf7W5AP2PzgH
06:15 PM lcnc-relay: <skunkworks8841@> https://youtu.be/E2t0y2EsSO8?si=Lqvoyt4lQbd1VPGm
06:22 PM lcnc-relay: <lesliet@> skunkworks8841@: is this your machine? The rigid tapping is hnnnnng
06:23 PM lcnc-relay: <skunkworks8841@> Yes
06:23 PM lcnc-relay: <lesliet@> nice!
06:23 PM lcnc-relay: <skunkworks8841@> Want your mind blown?
06:23 PM lcnc-relay: <lesliet@> sure
06:24 PM lcnc-relay: <skunkworks8841@> https://youtu.be/C0Wz8vnFAQU?si=MeAX6qB2eHXKSCSD
06:25 PM lcnc-relay: <lesliet@> very cool
06:32 PM lcnc-relay: <lesliet@> the other machine I always love to watch is a swiss machine
06:39 PM lcnc-relay: <skunkworks8841@> https://www.youtube.com/watch?v=qMLz4kWoAEI
06:59 PM lcnc-relay: <lesliet@> skunkworks8841@: you have fun projects
06:59 PM lcnc-relay: <skunkworks8841@> keeps me sane
06:59 PM lcnc-relay: <skunkworks8841@> mostly
07:39 PM lcnc-relay: <skunkworks8841@> I don't think I have actually looked at a 440 in person - but I added about a 5inch spacer on the Z column to give me more room
07:44 PM lcnc-relay: <skunkworks8841@> https://electronicsam.com/images/greenmachine/20180831_162717.jpg
07:44 PM xxcoder: reminds m of that joke
07:45 PM xxcoder: "yo I heard you like mill, so I put mill on mill"
07:46 PM lcnc-relay: <skunkworks8841@> lol
07:46 PM lcnc-relay: <skunkworks8841@> that is how I made sure the base was square with the column
07:47 PM lcnc-relay: <skunkworks8841@> I left it with the column tipping a few thousands back over its whole distance..
07:47 PM lcnc-relay: <skunkworks8841@> figurning the spindle would flex it forward a bit
07:47 PM lcnc-relay: <skunkworks8841@> it was just a guess.
07:48 PM lcnc-relay: <skunkworks8841@> some times I go by - it 'felt right'
07:48 PM lcnc-relay: <skunkworks8841@> and that has worked quite well with me.
07:50 PM lcnc-relay: <skunkworks8841@> I guess that is what experience is.
08:00 PM lcnc-relay: <skunkworks8841@> lol - I grew up watching dad make edge of the envelope calculations... THe only thing he sucked at calculating for some reason - was how much concrete we had to mix for a given pour...
08:00 PM lcnc-relay: <skunkworks8841@> it always seemed like we always needed 2 times as much
08:06 PM acer is now known as _unreal_
08:13 PM _unreal_: skunk your reminding me of me. took me 2 years to clear my dads house
08:13 PM _unreal_: houses
08:14 PM _unreal_: looking at the latest video from 9days ago
08:16 PM lcnc-relay: <skunkworks8841@> Lol.. yes.