#linuxcnc Logs

May 12 2021

#linuxcnc Calendar

12:12 AM -!- #linuxcnc mode set to +v by ChanServ
12:32 AM veegee: MeshCAM looks interesting. Not overpriced and not rentalware
12:34 AM roycroft: freecad continues to frustrate me because it's about the most feature-rich of the freely-available cad software packages, but is too weird for me to be able to make enough sense of it to be productive with it
12:34 AM roycroft: it's almost like it was written by germans :)
12:35 AM sensille: .oO ( ... )
12:49 AM XXCoder: im been working on freecad projects for days lol
12:49 AM XXCoder: the game board and other one
01:08 AM Deejay: moin
04:08 AM Loetmichel: hehe, small things that make you happy #521: just struggled with shoving braided copper wire shield over cabling the whole morning. Just made a small hollow "bullet shape" plastic part on the 3dprinter to put on the end of the cable... MUUUUUCH easier!
04:21 AM Tom_L: morning
04:22 AM Tom_L: veegee, all the cad cam is moving to the cloud. my kid is taking mastercam at the vo'tech currently. the cad part isn't the greatest but it is a popular package among small machine shops
04:23 AM Tom_L: the rest use catia around here
04:34 AM Loetmichel: Catia? you won the lottery?
05:40 AM JT-Cave: morning
07:11 AM mrec_: hmm I'm seeing a super strange behaviour dir is released before step is finished (in one direction, open loop). I'm now adding closed loop to a second stepper but that one seems to behave different
07:11 AM mrec_: could this be a wrong linuxcnc configuration?
07:13 AM mrec_: I'm directly measuring the pins of the parallel port
07:19 AM mrec_: oh yes linuxcnc wrong configuration for X on the lathe
07:33 AM mrec_: interesting.
08:47 AM Loetmichel: GAAAAAAH! Customers!!! just got a call... The rocket launcher consoles we build at the moment will have a lead acid battery inside. they need holes for venting HHO... and they remember that "insigificant fact" when all enclosures are already at the painter. WHY?
08:51 AM veegee: Tom_L that's depressing. I did hear that mastercam is generally the popular one
08:52 AM veegee: I was able to easily pirate Inventor CAM though, so that'll do. And it'll never deactivate
08:52 AM veegee: And Inventor CAM is apparently the same as Fusion360's "manufacture" workflow
09:09 AM jymmmm: morning
09:33 AM mrec_: does anyone know about stepper motors? I have the problem: very slow speed is okay, then there seems to be some speed where the motor goes crazy (the motor is jumping a bit backward sometimes) above that speed everything is nice again
09:33 AM mrec_: it seems like there's a "torque hole" at around almost 1 turn per second
09:36 AM Loetmichel: not a torque hole
09:37 AM Loetmichel: resonance
09:37 AM Loetmichel: the mass is still accelerating when the next step comes and it skips/backtraces because of that
09:38 AM Loetmichel: below that speed it can accelerate , move decellerate before the next step comes, above that speed it is already in the next position when the next step comes so no need for deceleration. so its smooth again
09:39 AM Loetmichel: onyl when the next step comes at the time when its still trying to stop again that will happen
09:39 AM Loetmichel: @ mrec_
09:41 AM veegee: mrec_ midband resonance
09:42 AM veegee: Gecko drivers claim to eliminate this problem. I've been trying to research how they do it
09:42 AM veegee: mrec_ https://www.geckodrive.com/support/step-motor-basics/mid-band-instability.html
09:43 AM Loetmichel: veegee: probably adjusting the current/torque by frequency?
09:43 AM veegee: Loetmichel they claim by adding second order damping to decrease phase lag so the motor doesn't sustain oscillation
09:44 AM veegee: I wonder if there are other stepper drivers that do this
09:44 AM veegee: See also: https://forums.parallax.com/discussion/139086/stepper-motor-midband-resonance-compensation
09:45 AM Loetmichel: nifty!
09:49 AM veegee: Have to drop off my flatbed crane truck for certification. I don't want to take a taxi back. I'm going to hoist my motorcycle onto the bed with its crane and then hoist it back down so I can ride back to the workshop
09:49 AM veegee: Now just have to pick some decent hook points for the sling
09:55 AM mrec_: this midband resonance is more visible if there's some load no? or is it also visible on a normal motor?
09:55 AM mrec_: normal motor, bare motor without load
09:55 AM mrec_: I just don't want to take the belt off for testing
09:57 AM Loetmichel: the resonance shifts with load an rotor mass
09:58 AM mrec_: ok, good that I added a microcontroller infront of the cheap driver so I can just jumpwire that part and set things dynamically
09:58 AM Loetmichel: sometimes you can shift the resonance out of the useable frequency band by adding mass to the shaft
10:04 AM veegee: mrec_ Loetmichel is right, the resonance changes with the load, similar to how the resonant frequency of objects changes when you change their mass and other characteristics
10:05 AM veegee: A book on classical mechanics should cover it
10:09 AM Loetmichel: yep
10:09 AM mrec_: I'm running this stepper at full steps, I'll play around with the settings first.
10:09 AM mrec_: current settings.
10:09 AM Loetmichel: try using half steps first
10:09 AM mrec_: I think I set it too high for this application not understanding that there's that midband resonance
10:09 AM Loetmichel: or even smaller imcrements if your driver supports that
10:09 AM mrec_: it does.
10:10 AM Loetmichel: smoothes out the mass a LOT
10:10 AM Loetmichel: stepper s at 1/1 step run very rough, ant 1/16 step they usually run smooth like silk
10:11 AM Loetmichel: you can even HEAR that
10:11 AM Loetmichel: because the jumps in torque are a lot less.
10:18 AM mrec_: microsteps change the situation again
10:18 AM mrec_: current changes did not have any effect
10:21 AM Loetmichel: as i said: microsteps change the torque curve from a square wave to a more sinusoid thing
10:21 AM Loetmichel: smoothing out the resonances BIG time.
10:21 AM Loetmichel: if you can afford the higher clock frequency thats the best/easiest way to solve the problem
11:00 AM mrec_: how do the stepgens of the fpga boards work do they still rely on the cpu or are they just auto-releasing the signals to lower the required cpu spec by half?
11:35 AM mrec_: ok found the documentation about stepgen
12:15 PM rs[m]: mrec_: I assume you are talking about mesa cards? http://linuxcnc.org/docs/html/drivers/hostmot2.html#_stepgen
12:15 PM rs[m]: dirhold dirsetup steplen and stepspace define the pulses
12:15 PM rs[m]: the nanoseconds are probably rounded up to some integer multiple of an internal FPGA period like 1/200MHz depending on type of fpga board
12:15 PM rs[m]: the stepgen algorithm is the same as in https://github.com/LinuxCNC/linuxcnc/blob/master/src/hal/components/stepgen.c#L628 AFAIU
12:15 PM rs[m]: regarding resonance, any jitter on your step pulse train makes mid band resonance worse, as does running the stepper with too much current.
12:16 PM rs[m]: full steps with no load on the motor and high current will cause the shaft to accelerate to a speed higher than average speed and possibly overshoot the next step position and bouncing back and forth until the next step arrives
12:16 PM rs[m]: if this bouncing becomes too violent the stepper stop rotating and make a sound like an impact wrench
12:16 PM rs[m]: this matrix <-> irc gateway is not without issues....
12:22 PM mrec_: the stepper just works fine with microsteps now
12:22 PM mrec_: I also lowered the current a lot and I did not experience any lost steps anymore
12:24 PM mrec_: it was a good lesson
12:25 PM mrec_: I still have my microcontroller between the parport and the stepper controller
12:26 PM mrec_: I thought about doubling the steps by using rising and falling edge detection
12:26 PM mrec_: but it's not really necessary
12:27 PM mrec_: I'll never turn parts at 7mm/sec (x axis)
12:29 PM rs[m]: mrec_: you could use the microcontroller to generate the steps if you can figure out some form of realtime communication with linuxcnc
12:29 PM rs[m]: that would lower jitter significantly
12:34 PM mrec_: it's connected to the parallel port
12:35 PM mrec_: via optocoupler.
12:35 PM mrec_: PC817C for step, PC817 for direction
01:03 PM JT-Shop: servo is toast, I damaged some wires on the tacho windings
01:27 PM Tom_L: :/
01:27 PM Tom_L: can you find another?
01:31 PM JT-Shop: prob not a direct replacement but yea I could get a chinlee ac servo and drive
01:33 PM mrec_: now the only item that is left on the mini lathe is the bldc motor for the spindle, the speed goes down easily if some load applies
01:33 PM mrec_: I've seen controllers with some potentiometers, mine doesn't have that and it's completely coated with epoxy
01:38 PM Tom_L: JT-Shop, no way to fix the wires?
01:38 PM Tom_L: i pulled some off an armature once and was able to solder them back on
01:40 PM JT-Shop: tiny little buggers
01:41 PM Tom_L: got nuthin to loose at this point..
01:41 PM Tom_L: -o
01:46 PM JT-Shop: nothing to gain wasting my time trying to repair a bunch of cut wires I know I can't do
01:46 PM roycroft: i picked up my failed motor yesterday
01:46 PM roycroft: it came in a box
01:46 PM roycroft: disassembled
01:47 PM roycroft: i have not had time to look at it yet
01:47 PM roycroft: i'm thinking i should just hang on to it for a while - there's a lot of copper in it
01:47 PM roycroft: it will certainly be worth a lot of money if i sit on it for a few years
01:52 PM Tom_L: JT-Shop, that one wasn't a lcnc conversion was it?
01:59 PM Rab: roycroft, they didn't put it back together?!
02:00 PM roycroft: no
02:00 PM roycroft: i did not ask them to
02:00 PM roycroft: and they charge by the hour, so they stopped as soon as they found the problem
02:00 PM Rab: Insulation breakdown?
02:01 PM roycroft: they said it needs to be rewound
02:01 PM roycroft: insulation breakdown would be my gess
02:01 PM roycroft: guess
02:01 PM roycroft: but i'll know better when i get it out of the trunk of my car and take a look at it
02:01 PM roycroft: meanwhile, my new motor will arrive tomorrow
02:04 PM * Tom_L decides not to go tune on his spindle motor as motor problems seem to be a theme this week
02:18 PM roycroft: yes, this is not a good motor week
02:33 PM CaptHindsight: anyone know how modern crank and rod bearings are produced? Stamped and then ground to size or?
02:41 PM roycroft: capthindsight: https://www.youtube.com/watch?v=4tFOBgtAqdc
02:41 PM roycroft: the captions are entertaining, and the auto-generated subtitles even more entertaining
02:42 PM roycroft: it appears that modern bearing manufacturing involves trampolines
02:43 PM roycroft: and for quality control they must pass the first inspection, the final inspection, the inspection, and the factory inspection
02:50 PM CaptHindsight: yeah, saw the Chinese bearing videos
02:52 PM CaptHindsight: I found this video more entertaining https://www.youtube.com/watch?v=hv053lZutuo
02:53 PM CaptHindsight: in Hindi, it's also a great accent to use when ordering at a drive through, the thicker the better
03:01 PM roycroft: i did not see any trampolines in the pakistani video
03:06 PM Tom_L: https://dsportmag.com/the-tech/the-science-behind-modern-performance-engine-bearings-simple-complexity/
03:09 PM CaptHindsight: CL deal/surprise inside https://i.imgur.com/fUpRPD3.jpg
03:09 PM CaptHindsight: you've got rust
03:09 PM CaptHindsight: https://i.imgur.com/HWWswXn.jpg
03:09 PM roycroft: yeah
03:10 PM CaptHindsight: https://i.imgur.com/VCfxjCk.jpg
03:10 PM roycroft: that means you got the steel/cast iron you paid for, with some free oxygen attached
03:10 PM CaptHindsight: https://i.imgur.com/KrR1Y36.jpg
03:10 PM Tom_L: what's wrong with that?
03:11 PM roycroft: looks pretty broken-in to me
03:11 PM CaptHindsight: even got up top on the side with the sealed valve cover, like they tumbled the engine after adding water
03:11 PM roycroft: perhaps the engine was fished out of a lake
03:11 PM Tom_L: head gasket leak between the combustion and water jacket
03:12 PM Tom_L: or oil passages
03:12 PM CaptHindsight: Tom_L: head gaskets were fine
03:12 PM Tom_L: check close
03:12 PM Tom_L: antifreeze will pit the bearings though
03:12 PM CaptHindsight: concern is more internal
03:13 PM Tom_L: yeah so it seems
03:13 PM CaptHindsight: crack between water and oil
03:13 PM CaptHindsight: but there is a water line across the crank
03:13 PM CaptHindsight: looks like water sat level in the pan
03:14 PM CaptHindsight: most of the rust wipes off
03:14 PM CaptHindsight: so it wasn't for too long
03:15 PM CaptHindsight: I'll be pressure testing the water channels before boring
03:17 PM Tom_L: what's it out of?
03:17 PM CaptHindsight: Pontiac G6
03:18 PM CaptHindsight: roller lifers and rockers from the factory
03:18 PM Tom_L: can the crank be salvaged?
03:18 PM CaptHindsight: that used to be exotic not too long ago
03:19 PM Tom_L: not too much so with flat pistons
03:19 PM CaptHindsight: yeah, a little pitting in the journals, might take a few thou off and use the next bearing size up
03:19 PM CaptHindsight: Compression ratio: 9.8:1 stock
03:20 PM CaptHindsight: running street gas so won't be bumping that up
03:22 PM CaptHindsight: the factory got ~1hp / cu in
03:22 PM CaptHindsight: normally aspirated
03:23 PM CaptHindsight: if you beef the bottom up a bit supercharging gets it to 1.5-1.75:1 with not too much work..
03:24 PM CaptHindsight: still a washing machine
03:24 PM CaptHindsight: only 3.5L
03:24 PM Tom_L: my bud got a really cool fuel injection for his racecar
03:24 PM Tom_L: looks alot like a carb.. dunno what brand it is
03:26 PM Tom_L: what is that toothed ring in the middle of the crank?
03:27 PM Tom_L: you seemed to think my S10 was that same/similar engine
03:29 PM CaptHindsight: Tom_L: encoder wheel, reluctor
03:29 PM Tom_L: i never got that far into mine before i sold it
03:30 PM CaptHindsight: variable valve timing with pushrods
03:30 PM CaptHindsight: GM pretty much this push rod engine to the limits while keeping the price down
03:30 PM CaptHindsight: pushe/pushed
03:31 PM CaptHindsight: start again: GM pretty much this pushed this push rod engine to the limits while keeping the price down
03:35 PM Rab: Tom_L, throttle body injection? I've seen old TBI setups that were factory-fit onto V8 carburator mounts, when some models initially transitioned to EFI.
03:36 PM Rab: E.g. https://www.ebay.com/itm/351526013690
03:36 PM CaptHindsight: the engine I'm replacing from 85 has a single injector above the throttle body
03:37 PM Rab: And I guess the same concept is a current performance mod: https://www.holley.com/products/fuel_systems/fuel_injection/throttle_bodies/throttle_body_components/parts/500-6S
03:37 PM CaptHindsight: https://www.youtube.com/watch?v=BXMXywNBaWA
03:38 PM Tom_L: Rab, his is EFI but has a throttle body. i didn't look it over that closely
03:38 PM Tom_L: it seemed to be what they're all using now
03:39 PM Rab: CaptHindsight, they should be ashamed not to have blipped the throttle in the video.
03:44 PM Tom_L: my friend liked to do that but his neighbors didn't appreciate it
03:45 PM Tom_L: keith black big block
03:45 PM Tom_L: on his funny car
03:54 PM JT-Shop: Tom_L, yea the bp has emc running it
03:56 PM Tom_L: i didn't think you'd converted it
04:00 PM Tom_L: that won't be quite as bad adding a different servo
04:06 PM JT-Shop: it's the bp knee mill not the bp discovery 308 vmc
04:06 PM Tom_L: oh
04:06 PM Tom_L: so the vmc is ok?
04:10 PM JT-Shop: yea the vmc is still going
04:23 PM drdoc: yay, new phone tomorrow!
04:24 PM drdoc: I gave in and got a CAT
04:24 PM JT-Shop: 8 or 12 cylinder?
04:24 PM drdoc: 16
04:25 PM JT-Shop: that will rattle nicely
04:25 PM drdoc: yeah, buddy
04:25 PM drdoc: was it Waukeshaw or Detroit that had the split crankcase?
04:26 PM drdoc: basically 2 straight-sixes strapped together
04:27 PM JT-Shop: you talking about opposed piston like diesel subs?
04:27 PM drdoc: no, it was literally 2 separate crankcases
04:27 PM JT-Shop: most of the time I used to work on 16 cylinder EMD's the kind in railroad trains
04:28 PM JT-Shop: not seen any like that
04:29 PM drdoc: we had a couple of old light plants at Norton Drilling
04:29 PM JT-Shop: on one rig the rotary motor was a worn out CAT 8 cylinder and you could not turn it off during the winter lol
04:29 PM drdoc: lol
04:29 PM drdoc: I was present when a Cat 379 came unmanufactured once
04:30 PM JT-Shop: and those damn hydraulic starters on Detroits on workover rigs were a PIA lol
04:30 PM drdoc: we were laying down pipe and the junior floorhand started it up to fill the hole
04:31 PM drdoc: about 3-4 minutes late we hear this eeeeEEEEWHAM
04:31 PM drdoc: and a piston lands on the drilling floor
04:31 PM JT-Shop: damn
04:32 PM drdoc: the thing about a 379 is it'll run backward
04:32 PM drdoc: the guy had blipped the airstarter and it cranked right up... on the rebound
04:32 PM JT-Shop: ouch
04:32 PM drdoc: yup
04:33 PM JT-Shop: https://beemanequipmentsales.com/properties/cat-3508-800hp/
04:33 PM drdoc: ran just fine, except for the oil pump
04:34 PM JT-Shop: EMD's have a circular bearing under the piston so the piston can rotate and it's plated with silver so you can't use the same oil as detroit and cat...
04:35 PM JT-Shop: roustabout filled the emd oil tank with the wrong oil and when the motorman changed oil on all 3 16's a day later they started blowing the manhole covers off and filling the rig with smoke
04:35 PM drdoc: Crap, memory fails me yet again
04:35 PM drdoc: it was a D397
04:36 PM drdoc: something like 52 gallons to change the oil
04:36 PM JT-Shop: you know what they say about that... it ain't going to get better
04:37 PM drdoc: I don't have to know what they say
04:37 PM roycroft: how much is gasoline back east these days?
04:37 PM drdoc: I live it every samn day
04:37 PM roycroft: like in carolina or georgia
04:37 PM Tom_L: roycroft, they don't have any
04:37 PM drdoc: lol
04:37 PM Tom_L: it's 2.89 here
04:37 PM roycroft: well somebody has some
04:37 PM drdoc: JT-Shop: you're a roughneck?
04:37 PM Tom_L: and we're usually conservatively priced
04:37 PM roycroft: because the government had to issue a warning not to store gasoline in baggies
04:37 PM JT-Shop: for a while yes then motorman
04:38 PM Tom_L: last week it was 2.69
04:38 PM roycroft: it's been around $3.50 here for quite a while
04:38 PM roycroft: since before the pipeline shutdown
04:38 PM roycroft: well before then
04:38 PM drdoc: I was motorman for 7-8 years
04:38 PM roycroft: i'm just imagining it at $10 or more on the east coast
04:38 PM drdoc: they made me go up in the derrick and I hated it
04:39 PM roycroft: maybe this will finally drive us to adopt the metric system for real
04:39 PM JT-Shop: worked derricks on a standard derrick on a jackup for a few years too
04:39 PM roycroft: because gasoline would only be $2.50/liter
04:39 PM drdoc: not so much latching pipe but it was too much bookkeeping
04:40 PM drdoc: I was on a triple scope that had been blown over
04:40 PM drdoc: the derrick was twisted a tiny bit
04:41 PM JT-Shop: yikes I would not like to be up in a bent derrick
04:41 PM drdoc: when the driller came off the slips, a scope usually fish-poles a bit, right?
04:41 PM drdoc: it's meant to flex
04:41 PM drdoc: rig 12 did this hula hoop thing
04:42 PM drdoc: down-left-down-up-left-up
04:42 PM JT-Shop: I only worked once on a truck rig it was a double
04:43 PM JT-Shop: rest of the time was in the gulf or off the coast of west africa
04:43 PM drdoc: ah
04:43 PM drdoc: I get seasick, so that was never on the menu
04:43 PM CaptHindsight: plastic stuff must have a high demand, used equipment dealers are hunting for extruders
04:44 PM drdoc: CaptHindsight: what scale?
04:46 PM drdoc: I reworked an injection-molding style extruder for a 3D printer a few days ago
04:46 PM JT-Shop: those are usually 50-1500 ton injector
04:46 PM CaptHindsight: drdoc: all sizes od single and twin screw
04:46 PM CaptHindsight: od/of
04:47 PM drdoc: interesting
04:47 PM drdoc: JT-Shop: this was more like ounces
04:47 PM drdoc: little 4" screw
04:48 PM CaptHindsight: drdoc: extruding and injection molding is mostly automated, I'm surprised that plastic stuff still gets imported
04:48 PM drdoc: If he can make it work it'll be a very nice tool, but I don't think he's really thought it through
04:49 PM drdoc: CaptHindsight: I know. One of my profs in CAD College designs molds & tooling
04:49 PM drdoc: that product flow seems not-optimal to me
04:50 PM drdoc: design product here
04:50 PM drdoc: design tooling here
04:50 PM drdoc: low-end crap - produce tooling in asia
04:50 PM drdoc: high-end crap - produce tooling here
04:51 PM drdoc: ship tooling to asia for production
04:51 PM drdoc: ship product back
04:51 PM drdoc: ....
04:51 PM drdoc: watch asian knockoffs flood the market because the priates have access to tooling
04:51 PM CaptHindsight: it's all automated, don't see why to produce overseas unless you are in some crazy tax area
04:51 PM drdoc: *pirates
04:52 PM CaptHindsight: if it takes hands on then paying someone $5/hour vs $15 explains why
04:53 PM drdoc: I gathered that post-processing & assembly drives that
04:54 PM CaptHindsight: a recent factory in the great plaines told me that they can't find factory workers for $18/hr
04:54 PM roycroft: if you produce overseas you can avoid quality control checks and make your parts out of junk
04:54 PM drdoc: that too
04:54 PM CaptHindsight: great plains even
04:55 PM drdoc: there's also the EPA to deal with here, and OSHA
04:56 PM CaptHindsight: worled with a screw co in the US trying to reshore production
04:56 PM CaptHindsight: the factory in China would waste >70% of the coatings
04:56 PM drdoc: wow
04:57 PM CaptHindsight: worled/worked.... my typos today
04:57 PM roycroft: and shareholders who demand more profit, no matter how much money you give them
04:57 PM CaptHindsight: in order to coat just the screw heads they would just blast the whole jig that held the screws
04:58 PM drdoc: "works for me..."
04:58 PM CaptHindsight: paint supplier loved them
04:58 PM roycroft: yes, but the coating would be made out of recycled sugar and arsenic, and would not cost them anything, so wasting most of it would be no big deal
04:59 PM drdoc: CaptHindsight: seems like dipping would be easier & cheaper
04:59 PM CaptHindsight: roycroft: just on the fasteners for toys and children's furniture
04:59 PM roycroft: right
05:00 PM CaptHindsight: the rest are made from garbage
05:00 PM roycroft: for real machinery they would use proper coatings on their pot metal fasteners
05:00 PM drdoc: JT-Shop: you tossed me down the rabbit hole
05:00 PM Rab: On the Amp Hour podcast they were complaining about not only electronic part shortages, but delays in manufacturing finished plastic parts. No analysis of the issue other than saying it didn't seem to be a pellet shortage.
05:00 PM drdoc: new phone is a CAT S60
05:01 PM roycroft: i'm still trying to figure out how running an old version of exchange is the cause of the pipeline ransomware attack
05:01 PM CaptHindsight: Rab: not letting a crisis go to waste
05:02 PM drdoc: Rab: the plague has caused some pretty severe spot shortages
05:02 PM * JT-Shop is scratching his head trying to make a nest for a Telsa seat air conditioner part
05:02 PM roycroft: critical infrastructure is not connected to the internet in any way, so it's impossible to hijack an oob management network like that via an email virus
05:02 PM drdoc: SMD resistors, for example
05:02 PM roycroft: right?
05:02 PM Rab: drdoc, discretes were bad for a couple of years before the plague.
05:02 PM CaptHindsight: the auto makers cancelled their electronic part orders when the pandemic started
05:02 PM drdoc: not even close to now
05:03 PM CaptHindsight: due to slow sales
05:03 PM Rab: It was maddening seeing MLCCs pop in and out of stock.
05:03 PM roycroft: same with the lumber mills
05:03 PM JT-Shop: you can't sell what you don't have
05:03 PM CaptHindsight: so they went to the back of the line when orders stated back up
05:03 PM roycroft: they anticipated a slowdown of the construction industry so they slowed down their mill output
05:03 PM roycroft: but the construction industry actually ramped up
05:03 PM CaptHindsight: the other story is the water shortage in taiwan
05:04 PM drdoc: Rab: I can't remember what logic I was ordering this week, but Mouser sez the factory is refusing even back orders
05:04 PM CaptHindsight: drought has slowed production at TSMC
05:04 PM roycroft: and the mills never picked up production again until just now
05:04 PM Rab: I think the overall problem in the past 10 years is a lean toward JIT manufacturing, leaving no tolerance for any supply chain disruption.
05:04 PM roycroft: which is why we have $9 2x4s that used to cost $1.85
05:04 PM CaptHindsight: Rab: yeah that is a lot of it
05:05 PM roycroft: if i'm honest, rab, and as a person who believes in corporations paying their fair share of taxes, i'm not a big fan of property tax on inventory
05:05 PM drdoc: Rab: makes sense
05:05 PM roycroft: that's one of the big resons for the move to jit manufacturing
05:05 PM JT-Shop: most local builders have stopped building
05:05 PM CaptHindsight: Rab: because children don't seem to be able to imagine anything happening to disrupt manufacturing
05:05 PM Rab: roycroft, as someone who has to pay tax on sitting inventory, neither am I. ;)
05:05 PM roycroft: not only do you have money tied upon production and materials, and storage for your inventory, you have to pay taxes on the inventory until you sell it
05:06 PM roycroft: it's really kind of dumb
05:06 PM drdoc: JT-Shop: the housing market in austin has gone totally berzerk
05:06 PM JT-Shop: banks still lend on sq ft not lumber prices
05:06 PM roycroft: jt-shop: it hasn't slowed down here at all
05:06 PM roycroft: nor in most parts of the country
05:06 PM roycroft: there was a really brief slowdown at the beginning of the pandemic, but that only lasted for a few weeks
05:07 PM drdoc: marketable houses stay listed for days or hours, and sell over asking
05:07 PM CaptHindsight: JT-Shop: yes, sq ft not cubic feet, same for real estate prices
05:07 PM roycroft: yes
05:07 PM CaptHindsight: shop space with 12 ft ceiling sells/rentsfor the same as 30ft
05:08 PM CaptHindsight: banking is a real nice racket
05:10 PM CaptHindsight: https://www.homedepot.com/b/Lumber-Composites-Dimensional-Lumber-Framing-Lumber/N-5yc1vZc55w
05:10 PM CaptHindsight: https://www.homedepot.com/b/Lumber-Composites-Plywood-Sheathing-Plywood/N-5yc1vZc7q5
05:12 PM JT-Shop: 7/16" OSB at hd is $44 a sheet better hope your house don't burn down because your insurance money won't build you a new house just and outhouse
05:14 PM Tom_L: what little housing here is going well over lending price
05:14 PM roycroft: i pulled out my spare vfd at lunch today, planning on mounting it so it will be ready when the new motor arrives for my grinder
05:14 PM Tom_L: keeping 1st time buyers out of the market
05:15 PM roycroft: although it's huanyang, just like the old one, the mounting holes don't quite line up the same
05:15 PM roycroft: now i have to decide whether to modify the vfd or the mounting plate
05:15 PM roycroft: either of which is a chore
05:17 PM Tom_L: so the vfd i have has alot more options than the documentation i got for it
05:17 PM Tom_L: i wrote them ALL down though
05:17 PM roycroft: you got lucky then - you got some free features
05:17 PM Tom_L: might be nice to know what they all are
05:18 PM roycroft: yes
05:18 PM roycroft: the two error codes my old vfd displayed before it blew up are not documented
05:18 PM Tom_L: i know it supports modbus but there is no documentation provided for it
05:18 PM roycroft: but they both started with eo, and all the documented eo errors codes are load-side errors
05:18 PM Tom_L: and the chinese docs i got for a similar one talk about modbus but not the parameter list
05:19 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/PDF/BLDC/
05:19 PM Tom_L: i translated one or two of em but that's all they had to provide me
05:21 PM * roycroft decides that modifying the vfd mounting plate is the more correct thing to do, but will take at least 10x as long as modifying the vfd, and decides to go for the less correct, but faster/easier way
05:23 PM Tom_L: i'm not sure whether to mess with the startup delay or try to make the PI loop snappier
05:23 PM Tom_L: startup ramp time
05:23 PM Tom_L: it has a slowdown one too iirc
05:25 PM Tom_L: if i decrease the startup ramp the inrush current will go up too
05:25 PM CaptHindsight: institutional buyers are gobbling up the houses, then renting
05:26 PM Tom_L: yeah
05:26 PM CaptHindsight: why you can get cash for well over the asking price for your home just months ago
05:26 PM Tom_L: they're going for 30-40k over loan value
05:27 PM CaptHindsight: go capitalists, get rid of the home buyers, make everyone rent
05:27 PM Tom_L: alot more of em are living on the street now
05:27 PM Rab: That's been going on for a while, rent prices are cratering now (compared to the buying market).
05:27 PM CaptHindsight: you can't deduct rent from your income like a mortgage either
05:27 PM CaptHindsight: so double whammy
05:28 PM CaptHindsight: well the middle class doesn't defend themselves, so what do you expect to happen?
05:28 PM Tom_L: and the landlord isn't gonna keep them up either, they're just after the cash
05:29 PM CaptHindsight: what life is all about, coll,ect as much money/cash as possible
05:29 PM Tom_L: no
05:29 PM Tom_L: he who dies with the most toys wins!
05:29 PM CaptHindsight: then you take it to heaven with you :)
05:29 PM CaptHindsight: sure sure, makes perfect sense
05:29 PM CaptHindsight: toys, cash etc
05:30 PM Tom_L: leaving their siblings to fight over it
05:30 PM JT-Shop: he who dies with the most toys loses
05:30 PM CaptHindsight: in other words a compulsive obsessive, only with cash
05:30 PM Tom_L: and end up hating each other
05:30 PM -!- #linuxcnc mode set to +v by ChanServ
05:30 PM JT-Shop: he who dies last has all the toys
05:30 PM CaptHindsight: collect rubber bands and you're just a nut case
05:30 PM Tom_L: heh
05:31 PM JT-Shop: yeah rubber bands don't last long
05:31 PM Tom_L: no kidding
05:39 PM XXCoder: lol
05:59 PM -!- #linuxcnc mode set to +v by ChanServ
06:03 PM JT-Shop: this nest is kicking my ass I quit for the night
06:03 PM Tom_L: nest?
06:06 PM Tom_L: speaking of... there have been a growing number of bald eagles around here lately
06:06 PM Tom_L: kinda cool to watch em
06:22 PM -!- #linuxcnc mode set to +v by ChanServ
06:46 PM skunkworks: Tom_L: When I was a kid - I never saw a bald eagle.. Now there is a nest down the street...
06:46 PM skunkworks: https://www.youtube.com/watch?v=Nu-pFUC7_Iw
06:47 PM XXCoder: bald eagles is slowly making a comeback
06:47 PM XXCoder: ddt was so bad to them
06:48 PM XXCoder: actually using it yay
06:48 PM roycroft: automation direct are a little irritating
06:48 PM XXCoder: autocaptions is so irrating slow nowdays
06:48 PM CaptHindsight: I see baby pigeons out here, they do exist
06:48 PM roycroft: i have not received my new motor from them yet, but since i ordered it i've received three emails from them asking me to review it
06:48 PM roycroft: i'm not going to review something i don't have yet
06:49 PM CaptHindsight: "Don't have it yet, works as exepcted"
06:49 PM roycroft: and in hindsight, i should have remade the mounting plate for my vfd
06:50 PM roycroft: it was a bitch getting the new vfd to mount on it
06:50 PM CaptHindsight: thanks for reminding me, another ebay seller that creates the mailing label and then ships 3+ days later
06:50 PM roycroft: a lot of them don't have inventory - they get your order, they print a shipping label, then they order the item from their supplier
06:50 PM XXCoder: heh like seller i had bought from that grantuees 2 day shipping, and it certainly arrived after 2 days... after waiting 2 weeks for them to ship in first place.
06:51 PM roycroft: that place i linked to a few weeks ago with good proces on noga did that
06:51 PM roycroft: i ordered from them, they said it would arrive in 2 days, and a week and a half later i contacted them
06:52 PM roycroft: they said it was out of stock and they just got some more, and would ship it immediately
06:52 PM roycroft: which they did
06:52 PM roycroft: i demanded that they refund the $12 i paid for shipping, and they did
06:52 PM roycroft: so it wasn't a totally horrible transaction
06:52 PM XXCoder: nice
06:52 PM roycroft: i'm usually fine with a shipping delay if they just tell me what's going on
06:53 PM roycroft: and that's what i told them - "if you were out of stock all you had to do was send me an email saying so, and when you expected more"
06:53 PM roycroft: but there was zero communication until i initiated it, so felt quite justified in requesting a refund on the shipping cost
06:53 PM XXCoder: indeed
06:55 PM roycroft: anyway, the vfd mounts on a 3/8" thick piece of steel plate that is attached to a pillar - it would have been a fair amount of work removing that, filling in the existing mounting holes with weld, drilling and tapping new ones, and painting it
06:55 PM roycroft: and the holes on the new vfd were off by less than the diameter of the screws, so i would have had to fill and redrill/tap
06:56 PM roycroft: i was dumb and thought that if i bought two of the same item at the same time the mounting holes would line up the same on both of them
06:56 PM roycroft: silly me
06:59 PM CaptHindsight: wish Fedex was honest, they just say delivery attempted when it wasn't
07:00 PM CaptHindsight: later changed their minds to 'damaged, returned to sender"
07:11 PM extorr is now known as exot
07:12 PM exot is now known as extor
07:30 PM Tom_L: ironic they release a 2020 coin with a bat on the back: https://catalog.usmint.gov/national-park-of-american-samoa-2020-rolls-and-bags-MASTER_SAMOA.html?cgid=2020-product-schedule
07:30 PM XXCoder: covid bats
07:34 PM Connor: okay. Setting up a lathe. I'm confused on the X axis. The X axis (cross slide) has 7" of travel. The home switch is on the side of the operator.
07:34 PM _unreal_: loooks like Its nearing time for me to replace some more bearings
07:34 PM Connor: Is that 0, or -7"
07:35 PM _unreal_: THE ONLY bearings I ever seem to have issue with are the lead screw one's
07:35 PM Connor: and is moving too the center of spindle, + or - ?
07:35 PM Tom_L: Connor, 0 is typically the center of the work
07:35 PM _unreal_: all others are chugging along just fine
07:35 PM Connor: 0 is center, okay. so, +7" or -7" on the operator side?
07:36 PM Tom_L: probably up to you
07:36 PM Tom_L: just make sure your cad knows wtf you're doing
07:36 PM Tom_L: there are lathes the tools enter from the back too
07:37 PM Connor: Yea, not on this one.. So, I'm thinking -7" is the operator side.
07:39 PM Tom_L: https://faculty.etsu.edu/hemphill/entc3710/nc-prog/nc-02-01.htm
07:39 PM Tom_L: that's their opinion
07:39 PM Tom_L: motion toward the spindle is minus
07:40 PM Connor: Wow, that's backwards to what I was thinking.. even on Z.
07:40 PM Connor: err.. wait.. no.. Z is right.
07:41 PM Tom_L: Z- eats material
07:41 PM Tom_L: X- eats material
07:41 PM Tom_L: so i dunno where they intend to set X0
07:42 PM Tom_L: and honestly it's been too long since i ran the okuma i don't remember
07:42 PM _unreal_: Tom_L, I hear m3 and m4 eat material as well
07:42 PM _unreal_: :)
07:42 PM Connor: I've done one lathe setup, and it's been too long ago.
07:42 PM Tom_L: _unreal_, my cutters eat material!
07:42 PM _unreal_: OOOOOH big boom... south florida lighting storm going opn
07:43 PM _unreal_: I eat material if I dont have a dust mask on
07:43 PM Tom_L: Connor, i still have the okuma quick reference but i doubt that would be in it
07:45 PM Connor: OKay, so face of the spindle on Z would be 0
07:45 PM Tom_L: iirc we set z to the end of the material not the spindle
07:45 PM Tom_L: we put soft stops near the spindle so it wouldn't hit it
07:46 PM _unreal_: soft as in bushing
07:46 PM _unreal_: of the rubber kind?
07:47 PM Tom_L: software
07:47 PM Tom_L: and no this reference has nothing on seting zero
07:48 PM Tom_L: lemme look at something..
07:49 PM Tom_L: i did a cad for a lathe part here a long time back maybe i can tell from it
07:50 PM Tom_L: on this part, X0 would be the material OD
07:53 PM Tom_L: wait a sec. it was oriented wrong and the axis weren't shown. X0 is actually the center
07:58 PM Tom_L: yeah, even on one of their sample parts, X0 is the center
08:03 PM Tom_L: Connor, http://tom-itx.no-ip.biz:81/~webpage/cnc/lathe_orientation.jpg
08:06 PM Tom_L: Z is the end of the part there as well
08:46 PM Connor: Tom_L: That looks like it's cutting on the back side
08:47 PM Connor: So, this machine has 24" Z travel, 8" on cross-slide, with about 6 1/2" on the operator side, and 1 1/2" over travel.
08:47 PM Connor: There will be a Z min limit switch at the head stock that's adjustable to account for chucks/faceplate. The home switch will be a few inches before that.
08:48 PM Connor: the home switch for the cross slide is extreme end of travel toward the operator.
09:14 PM Tom_L: Connor, true but the origins would be the same no matter the tool orientation
09:42 PM veegee: Ok shitty chinese motion control card died
09:42 PM veegee: Time to start putting together a proper setup
09:42 PM veegee: What would be y'all recommendation for a motion control card?
09:43 PM veegee: I'm looking into the mesa cards
09:46 PM roycroft: you're looking in the right place
09:50 PM Tom_L: veegee, his newest all in one card might do the trick
09:50 PM Tom_L: i'm not familiar with the board number
09:51 PM Tom_L: http://store.mesanet.com/index.php?route=product/product&product_id=311
09:51 PM Tom_L: that may be it
09:53 PM Tom_L: JT-Shop has em too but looks like he's out of stock right now: https://mesaus.com/product/7i96/
09:54 PM Tom_L: ethernet requires preempt-rt
09:55 PM veegee: ain't no thang, I have dedicated computers for this
09:55 PM veegee: Only $120? Can't go wrong
09:55 PM Tom_L: there are many solutions but that one is fairly compact
09:56 PM Tom_L: depends what interface you prefer
09:56 PM Tom_L: pci, pcie, ethernet, spi, parport etc
09:58 PM veegee: PCIe would be the best for low latency
09:58 PM veegee: I already have stepper drivers, so this should be the only thing I need
09:59 PM Tom_L: latency isn't so much an issue with mesa cards
09:59 PM veegee: I mean in general, Ethernet isn't great for realtime
09:59 PM veegee: ethercat is fine though
10:00 PM Tom_L: i've tested it and it seems to do rather well
10:00 PM roycroft: i have a 5i25 + 7i76
10:00 PM Tom_L: i started out with a parallel port so my cards are parallel interface
10:00 PM Tom_L: th 5i25 ie pci iirc
10:00 PM roycroft: yes
10:00 PM veegee: Yeah not saying it's not good, just making a general statement about Ethernet
10:01 PM Tom_L: in fact, ethernet on a rpi4 seems to work fine
10:01 PM veegee: I don't mind buying a couple of different ones. Didn't think they were this cheap
10:01 PM roycroft: and the 7i76 is the stepper bob
10:01 PM veegee: Tom_L you're running preempt_rt on rpi4?
10:01 PM Tom_L: running the cnc is about all you'd wanna do with it at once though
10:01 PM Tom_L: veegee, i have tested it yes
10:02 PM Tom_L: buster?
10:02 PM veegee: ok nice
10:02 PM Tom_L: it's been a while
10:02 PM Tom_L: there is a build for it
10:02 PM veegee: I have an Intel Xeon E5 at the very minimum so regardless of the I/O mechanism, it'll be able to handle it just fine
10:03 PM Tom_L: http://buildbot.linuxcnc.org/dists/buster/2.8-rtpreempt/binary-armhf/
10:03 PM veegee: The Xeon E5 is the weakest system I have just because I haven't gotten around to donate it yet
10:03 PM roycroft: the ethernet-based cards were available when i bought my mesa hardware
10:03 PM roycroft: i don't remember why i decided the parallel interface was better than ethernet
10:03 PM roycroft: but i did
10:03 PM Tom_L: they weren't when i did mine
10:03 PM roycroft: and i do recall chatting with both pcw and jt about it for quite a while before buying the stuff
10:03 PM Tom_L: i have some to test though
10:03 PM roycroft: as well as some other folks here
10:05 PM roycroft: all that said, i bought the stuff and have powered it up and done some preliminary testing, but still don't have the cnc machine finished, so i can't say how well that gear performs from personal experience
10:05 PM roycroft: but i have absolutely no doubt it will work brilliantly whenever i actually finish the build
10:06 PM roycroft: iirc jt has a kit with those two boards + a 25pin cable
10:06 PM roycroft: that actually has 25 wires
10:07 PM Tom_L: mine has 72 io
10:07 PM Tom_L: 7i90
10:07 PM Tom_L: i think
10:07 PM Tom_L: the ethernet counterpart is 7i80
10:08 PM Tom_L: but you still need some sort of daughter card
10:09 PM roycroft: i also have a 7i73 for a pendant
10:11 PM roycroft: if i bought it today i'd probably get a 6i25 instead of a 5i25
10:11 PM roycroft: but that was not an option at the time
10:12 PM roycroft: it is the pcie version of the 5i25
10:26 PM Tom_L: veegee, it's not always the speed of the pc that makes good latency
10:26 PM veegee: Why not the FPGA cards?
10:26 PM veegee: What are those used for generally?
10:27 PM Tom_L: the commands from the gcode are sent to the fpga and the fpga actually does the step generation etc
10:27 PM Tom_L: encoder etc
10:28 PM Tom_L: you don't need the best latency for a mesa card but it needs to be a somewhat reasonable number
10:28 PM Tom_L: and it uses the servo thread, not the base thread
10:29 PM Tom_L: later...
10:35 PM veegee: Ok looks like that's the route I should be going
10:35 PM veegee: that's a real motion controller
10:36 PM CaptHindsight: I want my dispersed processing https://video-images.vice.com/_uncategorized/1620745945823-image20.png?resize=800:*
10:38 PM veegee: Is there more information on the FPGA's firmware?
10:38 PM veegee: I'd like to take a look
10:39 PM veegee: That's definitely the route I'd like to go. I don't like the idea of a not-really-real-time computer doing motion control
10:39 PM CaptHindsight: everything is on the Mesa site, which board?
10:41 PM veegee: Something like this: http://store.mesanet.com/index.php?route=product/product&path=69_62&product_id=77
10:41 PM veegee: I'm interested in looking at the Verilog for the G code interpreting logic
10:41 PM veegee: And the logic for how it generates the motion steps
10:42 PM veegee: That more like a GRBL system and I like that
10:46 PM Connor: Quick question. with the 7i96, if it doesn't have power when the computer boots up, and I then give it power.. The Ethernet interface doesn't get a IP. If I down the interface and up it, it does. I've never seen this on a linux system.
10:47 PM Connor: What parameters do I need to add to the network to force it to keep the IP?
10:49 PM veegee: Connor which OS?
10:50 PM veegee: It's trivial to make it a static IP using its MAC address
10:50 PM veegee: then it'll keep that IP no matter what
10:50 PM CaptHindsight: veegee: http://www.mesanet.com/software/parallel/3x20.zip
10:50 PM -!- #linuxcnc mode set to +v by ChanServ
10:50 PM Connor: Debian, stock LinuxCNC img.
10:51 PM Connor: using network/interfaces file
10:51 PM Connor: I have auto eth0
10:51 PM Connor: and hotplug enabled too.
10:51 PM veegee: simple
10:51 PM veegee: Are you connecting the 7i96 directly to your eth0?
10:52 PM veegee: What does your network topology look like
10:52 PM veegee: and is your eth0 providing a DHCP server?
10:57 PM veegee: CaptHindsight not sure what you linked me, but I think this is what I was talking about: http://store.mesanet.com/index.php?route=product/product&path=65&product_id=163
11:01 PM CaptHindsight: veegee: dat wuz duh source fer dat board
11:01 PM CaptHindsight: .vhd
11:01 PM veegee: Oh, but not for interpreting G code and all that
11:02 PM veegee: The thing I linked is the actual motion control stuff
11:02 PM CaptHindsight: nope, dat is in LCNC
11:02 PM veegee: The one you linked is just for arbitrary IO
11:02 PM CaptHindsight: yeah dat you linked wuz not fer LCNC
11:02 PM veegee: yeah, the one I linked does the motion control in the FPGA
11:02 PM CaptHindsight: yup
11:03 PM pcw_home: conner: if you are editing the interfaces file, take a look at the hm2_eth manual page
11:03 PM veegee: I'll buy the ethernet one as well as this. I should experiment
11:07 PM pcw_home: my interfaces file looks like this:
11:07 PM pcw_home: auto eno1
11:07 PM pcw_home: iface eno1 inet static
11:07 PM pcw_home: address
11:07 PM pcw_home: hardware-irq-coalesce-rx-usecs 0
11:19 PM mrec_: the difference between those chinese carbide inserts and korloy are extreme...
11:19 PM mrec_: korloy takes quite some time to grind it back into shape, the chinese ones are soft