#linuxcnc Logs

May 12 2022

#linuxcnc Calendar

12:03 AM * xxcoder8265[m] uploaded an image: (133KiB) < https://libera.ems.host/_matrix/media/r0/download/jauriarts.org/TVMdUoYDKRAHONFhoJHiLDrc/unknown.png >
12:11 AM XXCoder: some progress
12:11 AM XXCoder: left is orginial mascot. right is re-created mascot that I later edited
12:11 AM XXCoder: center is brand new one. made from body of left and some parts of right
12:11 AM XXCoder: goggles is entirely new. body is reshaped a little
12:19 AM * xxcoder8265[m] uploaded an image: (6KiB) < https://libera.ems.host/_matrix/media/r0/download/jauriarts.org/BIqMCgLlUajMZciiQfQuWlYx/unknown.png >
12:19 AM xxcoder8265[m]: endmill is far more easy to see at smaller size now
12:19 AM xxcoder8265[m]: strong border and lighter
12:20 AM * xxcoder8265[m] uploaded an image: (32KiB) < https://libera.ems.host/_matrix/media/r0/download/jauriarts.org/jnDslWxOByHkrZcbeOfCiDnK/unknown.png >
12:20 AM xxcoder8265[m]: the endmill alone
12:28 AM * xxcoder8265[m] uploaded an image: (40KiB) < https://libera.ems.host/_matrix/media/r0/download/jauriarts.org/jGOHzumgQJEsDyueexjabXDq/g2923.png >
12:28 AM xxcoder8265[m]: provisional. Looks a lot better
01:23 AM rs[m]: xxcoder: I would increase the contrast of the flutes and perhaps give it a fancy blueish coating ;)
01:23 AM XXCoder: its diffult to increase contrast of only flutes
01:24 AM XXCoder: its only 4 parts, and very complex shape
01:26 AM XXCoder: well I might be able to overlay flutes with mostly transparent white to lighten them
01:48 AM randy: morning
01:51 AM Deejay: moin
02:55 AM CaptHindsight[m]: XXCoder: nice, I'll work on the 3d version
02:55 AM XXCoder: cool
02:57 AM CaptHindsight[m]: probably use NX and then export in a few flavors
03:00 AM * xxcoder8265[m] uploaded an image: (21KiB) < https://libera.ems.host/_matrix/media/r0/download/jauriarts.org/PxLDOGhYDfvsRuOSgClRZYgs/unknown.png >
03:01 AM xxcoder8265[m]: More contrast endmill. dunno if it works..
03:01 AM XXCoder: rs[m]:
03:11 AM XXCoder: CaptHindsight[m]: what you think? mini one is https://media.discordapp.net/attachments/970073761770512384/974216597227065344/unknown.png
03:11 AM XXCoder: it does look good but then dunno
03:11 AM XXCoder: its a endmill, much easier to see
04:22 AM -!- #linuxcnc mode set to +v by ChanServ
04:43 AM Loetmichel: Hmmm... I just cut open an Instant coffee pack with my Leatherman Wave and noticed that i do a "rotate 720°" flourish before i put it back into its belt holster. Every singe time i holster it. Does that make me robocop now?
04:49 AM Tom_L: morning
04:51 AM Loetmichel: mornin' tom
04:52 AM Loetmichel: on another account: having a multitool on you belt in a "quick out" holster makes you aware how often a day you COULD use a tool if you had one at hand :)
05:11 AM JT-Cave: morning
08:43 AM mrec: does anyone know the price for stainless sheets eg. 1mm?
08:43 AM mrec: 304 or 304L
12:17 PM -!- #linuxcnc mode set to +v by ChanServ
12:22 PM Alicrow-phone: So the first linear scale arrived yesterday and I tested it with the oscilloscope. As I suspected, it's quadratic encoding just like rotary encoders (with A and B channels). However, there does not seem to be an index signal. That's not a problem, right? The servo control logic (Mesa 7i40) doesn't actually require the index signal, right?
12:23 PM Tom_L: likely wouldn't be on a glass scale
12:24 PM Tom_L: not unless you're doing synchronized motion
12:25 PM Alicrow-phone: Synchronized motion? Isn't one of the main points of CNC that it precisely controls and synchronizes the motion between axes?
12:26 PM Tom_L: then you need the index channel
12:26 PM Alicrow-phone: Otherwise, you're really limited as to what shapes you can cut.
12:27 PM pcw-home: Index is chiefly for more precise homing
12:28 PM Alicrow-phone: Oh, right. Forgot it's used for homing. Was thinking it was just an extra check in case you missed a pulse.
12:46 PM Alicrow-phone: I think the scale is supposed to have a "reference mark" channel with a mark on an interval following a mathematical function, which can be used to determine the absolute position of the scale. Sounds like that should be able to serve the same purpose as the index mark (if not eliminate the need for homing all-together). However, I didn't see any output when I connected that pin to the oscilloscope. Nothing explicitly says what that pin is for; I
12:46 PM Alicrow-phone: just have a pinout chart that marks it "R1", so it might be something else. Or broken.
12:47 PM Alicrow-phone: By any chance does anyone have any insight into that?
12:56 PM pcw-home: Your scale may not have that option
01:05 PM Alicrow-phone: Well, when I opened up the D-sub connector at the end of the scale, that pin had a wire soldered to it (unlike the pins that were reported unused in the pinout diagram), so it should do *something*
01:49 PM CaptHindsight[m]: https://youtu.be/XsEIamdzsZs?t=45 close enough
01:50 PM CaptHindsight[m]: they might be suppliers to Chevy
01:58 PM CaptHindsight[m]: and the QC process https://youtu.be/XsEIamdzsZs?t=1930
01:59 PM XXCoder: I hate that that video is bit sped up
02:02 PM MrSunshine: hmm sk20 and iso20 .. are they the same ?
02:18 PM CaptHindsight[m]: XXCoder: nah you just have to move fast to keep up with CNC
02:18 PM XXCoder: sped up, no mistake :P
03:38 PM sparafucile: names
03:41 PM Tom_L: faces
04:35 PM Getty is now known as GettyOld
05:09 PM JT-Shop2: chickens
05:13 PM Tom_L: eggs
05:13 PM XXCoder: egg was first, scientists say
05:14 PM XXCoder: yo
05:14 PM Tom_L: wtf do they know?
05:14 PM XXCoder: lol
05:15 PM XXCoder: surpising simple enough. living things dont really mutate. but born variants do happen. it might be 99.9% to 100%, but definitely born chicken 100%
05:15 PM XXCoder: so egg is first
05:16 PM Tom_L: if you believe that
05:16 PM XXCoder: I dont belive or disbelive on science
05:16 PM XXCoder: I have reasonable doubt or not
05:16 PM XXCoder: this one I have no reasonable doubt
05:31 PM * JT-Shop2 still can't figure out how this stock is not flat after sizing it in the drum sander
05:57 PM roguish[m]: JT-Shop2: heat and moisture warpage?
05:58 PM JT-Shop2: temperature is constant and humidity keep arounf 50
05:59 PM JT-Shop2: %
05:59 PM JT-Shop2: the surface is convex across the width
05:59 PM roguish[m]: sanding both sides evenly?
05:59 PM roguish[m]: oh, it's cupping....
06:00 PM JT-Shop2: poking out in the middle, it's aspen so pretty soft
06:01 PM roguish[m]: better call Roycroft
06:04 PM JT-Shop2: just don't use aspen for drawers any more
06:05 PM JT-Shop2: it seems impossible to get anything other than a flat surface with the drum sander but I did
06:05 PM roguish[m]: clever guy
06:06 PM JT-Shop2: I do like the incra finger joint jig
06:06 PM XXCoder: entry and back of planar even?
06:06 PM XXCoder: honesly dunno lol
06:07 PM JT-Shop2: yep, feeding the boards in length wise and there are two pressure rollers one on each side of the sanding drum
06:07 PM JT-Shop2: I've only see that with the aspen, never with harder wood
06:09 PM JT-Shop2: I got most things moving on the Whirlpool automatic assembly machine today so taking tomorrow off and going to Echo Bluff State Park for lunch
06:11 PM JT-Shop2: roguish[m]: one side is perfectly flat, didn't touch it
06:12 PM roguish[m]: no clue man. seems like a mystery
06:14 PM JT-Shop2: yep blew my mind that it ended up like that
06:14 PM JT-Shop2: my buddy at Revere Plastics told the MSC guy that I just work for him to pay for my toys
06:15 PM JT-Shop2: he said I'm retired
06:15 PM roguish[m]: well, do ya?
06:15 PM JT-Shop2: no, I enjoy the challenge of figuring stuff out
06:16 PM JT-Shop2: the money is just extra icing on the cake, I like to keep my mind challenged
06:17 PM * JT-Shop2 wanders inside for the night
07:12 PM fluffywolf: There's a used older plasmacam table on craigslist. It supposedly uses a parallel port connection to an ancient pc running ancient windows software. What're the odds of it being easy to use with linuxcnc? googling isn't readily finding someone saying they've actually done it.
07:16 PM fluffywolf: hrmm, just found a forum post saying it's entirely proprietary and the protocol doesn't resemble anything linuxcnc is going to talk. meh.
07:16 PM XXCoder: well theres alwayus option to completely gut it
07:16 PM XXCoder: replace it with your own hardware
07:17 PM fluffywolf: yeah, I'm hoping to avoid that.
07:18 PM fluffywolf: I've found a number of posts saying the plasmacam people are fucking assholes and will not give you functioning software for older machines, and it sounds like no software is included with the one on craigslist.
07:18 PM CaptHindsight[m]: most CNC software that runs on Windows uses USB
07:19 PM fluffywolf: this is an old table that uses a parallel port connection to a proprietary control system, from what I've been able to find.
07:19 PM fluffywolf: it sounds like at least some portion of the motion control is done on their board, no real-time signals on the parallel port.
07:19 PM fluffywolf: so it's probably not possible to use with linuxcnc unless I gut it and start over with my own servo drivers.
07:20 PM CaptHindsight[m]: ah then you'd have to see what their LPT controller actually does
07:20 PM CaptHindsight[m]: with LCNC it can be LPT to BOB to Step and Dir drives
07:20 PM XXCoder: what motion does it use? giant servo, stepper, etc?
07:21 PM fluffywolf: some decently-sized servos from the looks of it
07:21 PM CaptHindsight[m]: brushed DC servos?
07:21 PM fluffywolf: CaptHindsight[m]: it's servos. I'd probably use a mesa something-e board and some servo drivers...
07:21 PM fluffywolf: I'd guess so.
07:21 PM fluffywolf: it's not fancy enough to be 3-phase.
07:22 PM CaptHindsight[m]: with LCNC you can often reuse the drives and just change the PC to LCNC and buy a Mesa card to interface to the drives
07:23 PM fluffywolf: depends on how integrated their driver board is.
07:24 PM CaptHindsight[m]: old drives were often analog, so your cost might be a new/old PC and some Mesa cards
07:24 PM fluffywolf: I was hoping it'd magically work, but since I asked the question originally I've found some more-useful forum posts that make it sound pretty unlikely to be possible to make work without at least some new hardware.
07:24 PM CaptHindsight[m]: no way to know without looking inside
07:25 PM fluffywolf: also found a number of posts saying it's pretty much impossible to make their older tables work unless the original software is included, since plasmacam absolutely will not give you a working license file no matter how nicely you ask.
07:25 PM fluffywolf: I hate corporations.
07:25 PM CaptHindsight[m]: magic is only on holidays and inside school doorways
07:26 PM CaptHindsight[m]: what price range is the plasma in?
07:26 PM fluffywolf: $500, no plasma cutter included.
07:29 PM fluffywolf: the seller is going to check with the last user to see if he can find the pc and stuff to go with it. would make it a lot more useful if it came with working software.
07:30 PM Tom_L: more costly too
07:32 PM CaptHindsight[m]: is the table in pretty good shape?
07:32 PM fluffywolf: it's surplus from a high school, so...
07:33 PM fluffywolf: if it's anything like my surplus-from-a-high-school lathe, it's been crashed in every conceivable fashion and then some.
07:33 PM fluffywolf: https://images.craigslist.org/00a0a_aghtHnv2oKCz_0lM0t2_1200x900.jpg
07:33 PM CaptHindsight[m]: not heavily used but lots of ooops
07:33 PM XXCoder: honestly probably most of expense is hauling it home
07:34 PM CaptHindsight[m]: oh, a smaller one
07:34 PM fluffywolf: my lathe is beyond heavily used. lol. I had to cut the ends off the tapered gibs to be able to slide them halfway through the saddle to try to take up all the play...
07:34 PM fluffywolf: (with shims on the wide ends)
07:34 PM fluffywolf: yeah, 4x4
07:34 PM XXCoder: whats your budget concerns like
07:35 PM fluffywolf: I have no money and nowhere to put it. :P
07:36 PM CaptHindsight[m]: I'd pass, save up, get space, etc etc
07:37 PM fluffywolf: found a forum post saying the original controller is entirely integrated, with the drivers on the same board as the motion control.
07:38 PM fluffywolf: so to linuxcnc it, I'm looking at tossing everything before the motors.
07:40 PM fluffywolf: has 12 IRF840s on it, which would be three full bridges, so definitely brushed servos.
07:40 PM CaptHindsight[m]: to keep the cost low it would require elite level cheapskate skills on ebay
07:40 PM fluffywolf: yeah, a red and a black to each motor
07:41 PM fluffywolf: I'm pretty good at that. :)
07:42 PM fluffywolf: hrmm, one forum post says " Chances of you using original servo motors with another control are slim to none.", which I don't understand, if they're just brushed servos...
07:43 PM fluffywolf: two posts down is another post pointing out that plasmacam absolutely will not provide working software to purchasers of used machines...
07:44 PM fluffywolf: another post mentioned needing the serial number off the table... I guess the licenses are tied to a serial that's also stored in the controller.
07:47 PM CaptHindsight[m]: maybe it uses resolvers vs encoders
07:47 PM fluffywolf: I think it uses position encoders somewhere later in the drive system and the poster doesn't realize linuxcnc has no problem using this.
07:48 PM CaptHindsight[m]: might be
07:48 PM CaptHindsight[m]: most machine users are not machine designers
07:49 PM fluffywolf: yeah, another post confirms that. but linuxcnc has no problem with that kind of control loop.
07:51 PM fluffywolf: "We recommend using a Pentium compatible 166 MHz or faster PC, with Windows 95 or 98 installed."
07:52 PM Tom_L: 98SE preferred :)
07:53 PM XXCoder: modern os. could drink beer for last 2 years
07:54 PM fluffywolf: https://www.rapidwelding.com/images/XL/2-528XLG.jpg sure would be nice if I could just use the original box. lol
07:54 PM XXCoder: it ca be turned into pendant lol
07:55 PM fluffywolf: with a new switch board. heh. it sounds like it's all one board...
07:56 PM fluffywolf: if it came with working software, I could try reverse-engineering the parallel port protocol, but that might be more work than starting over.
08:00 PM XXCoder: HAH! one listing i see is 4'x4' torchmate for 10k dollars
08:00 PM XXCoder: blades look shot too
08:00 PM XXCoder: some people just want too much
08:04 PM Alicrow-phone: What's a decent ping time for the Ethernet mesa cards? Is 0.15ms okay?
08:15 PM roycroft: yes
09:45 PM _unreal_: Just took my daughter to the new strange movie. YEP worth it
09:45 PM _unreal_: FYI two ending clips
09:47 PM * roycroft has not been to the cinema in a long time
10:15 PM -!- #linuxcnc mode set to +v by ChanServ