#linuxcnc Logs

May 10 2020

#linuxcnc Calendar

12:07 AM _unreal_: yay almost done building my disable adapter
12:13 AM _unreal_: make a small error nthing major
12:13 AM _unreal_: just re-soldering a bit
02:31 AM Deejay: moin
05:33 AM JT-Cave: morning
05:33 AM XXCoder: yo
05:34 AM XXCoder: i must be bored, I cleaned out a empty dropper container and turned it into pressure difference display
05:34 AM XXCoder: display is overly strong word, its just a bottle still lol
05:42 AM JT-Cave: 49°F as forecast
05:43 AM JT-Cave: tonight and tomorrow night low 40's
05:43 AM XXCoder: here its 76f peak. yeserday was 80f
05:43 AM XXCoder: quite early for that
05:43 AM XXCoder: but its dropping into 50s for rest of week'
05:54 AM JT-Cave: atmospheric pressure display?
05:55 AM XXCoder: basically'
05:55 AM XXCoder: not sure if it will work with water, was orginially oil
05:55 AM XXCoder: (i saw it changing while i was slowly using it up across months
06:00 AM JT-Cave: https://www.youtube.com/watch?v=ZVdu03G1950
06:01 AM XXCoder: ah them pesky fence bugs need to be eaten ;)
06:01 AM XXCoder: cool
06:07 AM XXCoder: jt how the bottle works is pretty simple really, the pressure affects the air inside the dropper because of its rubber outside
06:07 AM XXCoder: and air inside bottle is under fixed pressure
06:08 AM XXCoder: so differences result in levels
06:08 AM XXCoder: I "calibrated" it to be zero at clear day at 80f
06:22 AM p0g0: JT-Cave, back to back 24f here, last night and the night before...record lows for the region
06:22 AM JT-Cave: wow
06:23 AM JT-Cave: Friday night was 37°F I had to cover the tomatoes and add 3000w of heat
06:23 AM XXCoder: polar votex was interesting
06:24 AM XXCoder: it covered virtually all usa but not here lol
06:26 AM p0g0: the tomatoes are not dead, but a bit wounded- double cardboard (box over box) w/hay on top of the inner box, the other Solanums were already beat, so I'll be restarting the eggplants & hadn't done any spuds yet anyway.
06:33 AM JT-Cave: trying to get some Cherokee Purple tomatoes to germinate, got 4 out of 6 with one still with seed leaves
06:33 AM JT-Cave: I had 6 nice ones about 3" tall and left them out while on a ride and it got too cold and they all died
06:42 AM p0g0: tomatoes are frail, but they throw hard (long lived) seed. You might get a bit better germination rates by leaching or scarifying (physical abrasion or mild acid)- a lot of tomatoes co-evolved with birds and turtles that ate them and shat the seeds. The cherry tomatoes are like that, Galapagos turtles and such.
06:44 AM p0g0: I have heirloom tomatoes from around here that have been on paper in glass in the refrigerator, maybe 8-10 years old that germinate pretty well, maybe 1 out of three seeds or so.
06:45 AM XXCoder: i wish we had method to stop time within volume
06:45 AM p0g0: speed of light?
06:45 AM XXCoder: would be amazing to preserve seeds that way, as well as many others
06:45 AM XXCoder: p0 altering C constrant would be a way to do it. set it to 0 inside box
06:46 AM p0g0: hmm, there are nifty seed banks around he world, tho one of the big ones has had global warming issues, n. europe where they never expected a thaw.
06:47 AM p0g0: given the extinction rates, biopreservation is a race against time now.
06:47 AM XXCoder: yeah
06:47 AM XXCoder: they have problem with water too, since they expected ice to be ice forever
06:48 AM p0g0: yeah, that thaw a couple of years back. It's a tough call to think of where ice will stay ice for the foreseeable future.
06:49 AM XXCoder: gonna sleep laters.
06:50 AM p0g0: All the glaciers in the US that I have been to have thawed...
06:55 AM Tom_L: 45°F
07:19 AM _unreal_: morning
07:39 AM elmo40: hey _unreal_
07:39 AM elmo40: any recent pics of your mess? ;-)
08:11 AM JT-Cave: wow just picked some strawberries
08:13 AM elmo40: picked? from plants in the ground?
08:14 AM elmo40: this early??
08:19 AM _unreal_: elmo40, not relaly
08:19 AM _unreal_: but I should take some
08:20 AM _unreal_: I've been working on the controller box mostly
08:20 AM _unreal_: lot of wiring
08:20 AM _unreal_: I also just redid some oof the drag chain wiring
08:20 AM _unreal_: neater 10x more room inside the chain
08:20 AM _unreal_: now I have room to get an other tube
08:21 AM _unreal_: the tub for water cooling the spindle is perfect for the feed side now I just need the same thing for the return
08:22 AM _unreal_: elmo it is may
08:22 AM _unreal_: elmo40, besides also depends on where you live
08:23 AM _unreal_: If your in NJ for example its been worm for a while. I'm in florida its ALWAYS growing season
08:28 AM JT-Cave: from my deck planters, the plants are ~15 years old or so
08:28 AM JT-Cave: 7a here
08:33 AM _unreal_: last few connctions and this little pcb is done
10:41 AM _unreal_: quiet today
10:46 AM jymmmm: good morning
10:50 AM Tom_L: hey jym
10:57 AM unterhaus: turns out the current location of my mesa daughterboards is a mystery
10:58 AM Tom_L: lost or in transit?
11:05 AM _unreal_: maybe it got corona virus?
11:25 AM unterhaus: Last I used them was on a bench that no longer exists
11:31 AM _unreal_: hum
11:31 AM _unreal_: dont feel bad I'm tearing apart this room "" cleaning"" trying to find my serial adapter chips for one of my mtor controllers
11:31 AM _unreal_: DOESNT MATTER. I can just swap the chip from one board to the other. just not smart and always a small risk of damage to the board.
11:32 AM _unreal_: Lost track
12:31 PM CaptHindsight: https://forum.linuxcnc.org/18-computer/39037-linuxcnc-orange-pi#167290
12:31 PM CaptHindsight: they have the integrated microcontroller stepping at up to 1MHz
12:32 PM CaptHindsight: I'd use this over the Rpi-4
12:32 PM CaptHindsight: no fpga required for open loop stepping
12:33 PM CaptHindsight: "A RISC core can sample the AB sequences pretty fast. Max input frequency can be up to 200-400 kHz. But I haven't any high res encoders to test it. So these rates are theoretical maximum (based on output rates)."
12:36 PM CaptHindsight: these ARM SOC's are more open source than the Rpi's
12:51 PM CaptHindsight: the Orange pi should have the Rpi header so it should plug into the Mesa boards
12:52 PM CaptHindsight: should/might
12:52 PM SpeedEvil: If I was more awake, I would find the thread doing the Pi as a realtime tiny micro by locking off one core from linu.
12:52 PM SpeedEvil: then you only have the comparatively tiny memory and IO latencies
01:02 PM CaptHindsight: we had a couple Allwinner (the SOC on the Orange pi) working with LCNC
01:03 PM CaptHindsight: one core for real time, and the rest for non real and software rendering
01:03 PM CaptHindsight: now the mali GPU has open drivers
01:04 PM CaptHindsight: and the allwinner can use uboot so no closed blobs
01:05 PM CaptHindsight: Allwinner vs Broadcom, allwinner ends up being all open source vs
01:10 PM SpeedEvil: VEry
01:11 PM SpeedEvil: I do wish Pi hadn't entered the marketplace the way they did, they killed a lot of promising possible projects and slashed volume on others.
01:16 PM CaptHindsight: no blobs vs giant blob
01:17 PM CaptHindsight: well after all it is Broadcom, on par with nvidia and intel for openness
01:21 PM CaptHindsight: https://linux-sunxi.org/AR100#Documentation all the ARISC specs
01:21 PM CaptHindsight: if only machinekit had used these devices vs TI
01:21 PM Tom_L: JT-Cave, what os are you using on your pi4?
01:27 PM jymmmm: Can't find a 1"-20 male throwaway to 1/2" female, only 1/4"
04:11 PM Deejay: gn8
05:25 PM _unreal_: hum
05:25 PM Tom_L: ho hum
08:39 PM net|: happy leap year
08:49 PM Thorhian: Can an insert mill like this ramp/plunge and make pockets? https://www.ebay.com/itm/163824884297
08:50 PM XXCoder: tend not to
08:50 PM Tom_L: i doubt it
08:51 PM XXCoder: but you can do this - drill, then use this to rough expand
08:51 PM Tom_L: XXCoder, i got the kit you suggested
08:51 PM XXCoder: errm what kit? my memorys like goldfish
08:51 PM Tom_L: pi
08:52 PM XXCoder: oh yes. yeah its pretty good kit. fan is little cheap but easily replaced
08:52 PM Tom_L: i got another heatsink case anyway
08:52 PM Thorhian: Ah, was wondering. I've been trying to learn about what different end mills and different insert mills as well. It's hard to find clear info about the differnt kinds of insert mills
08:52 PM XXCoder: indexable is great for high abuse like roughing
08:53 PM XXCoder: inserts even expensive ones like $45 ones, is still cheaper than say 1" endmill
08:53 PM Thorhian: I mean, you need to be able to do some ramping/plunging for some parts to rough them out, like keyboard cases I plan on making.
08:54 PM XXCoder: plunge more or less no, but you can ramp down
08:54 PM XXCoder: carefully.
08:55 PM Thorhian: Yeah, I wouldn't want to plunge, i was thinking something more helical like I do with my router and troichodal milling.
08:55 PM XXCoder: if you want helical bore suggest do drill first
08:55 PM XXCoder: leave a room for chips to fly out
08:56 PM XXCoder: larger ones dont need to be concerned with this, just ramp down as move around and remove material
08:56 PM Thorhian: Hmm, that would be a good idea in general wouldn't it. I've seen plenty of pockets made without pre drilling with normal endmills.
08:57 PM XXCoder: its not very common at work either
08:57 PM XXCoder: machines is tough enough to take it
08:57 PM Thorhian: I thought you were a Software Engineer? Or do you do machining as well lol?
08:58 PM XXCoder: never really got into software engineering career
08:58 PM XXCoder: couldnt get a job, then got into job training then been cnc machinist for 5 years
08:58 PM Thorhian: Noice
08:59 PM XXCoder: im getting pretty close to paying off useless college loans
08:59 PM XXCoder: if 2k a month thing happens here in usa, then i can wipe all of em in 2 months
09:04 PM XXCoder: anyway yeah facemills and such is really useful
09:05 PM XXCoder: just be bit careful with them
09:05 PM Thorhian: Yeah I have a facemill coming in the mill, I was just wondering about 90 degree shoulder mills.
09:05 PM Thorhian: mail*
09:05 PM XXCoder: i still remember one time we had a blackout, and one machine was running big 10 inserts facemill
09:05 PM XXCoder: well spindle dropped a little in blackout and broke all of em at once
09:06 PM Thorhian: XD
09:06 PM XXCoder: it was expensive inserts too, for very hard metal
09:06 PM XXCoder: 50 usd each I think so that was 500 usd gone in a blackout lol
09:06 PM norias: oh man
09:06 PM Thorhian: Oof.
09:06 PM norias: the one place i worked had these huge inserts
09:06 PM norias: ceramic
09:06 PM norias: looked like bars of soap
09:06 PM Thorhian: Yeah no I don't want anything that expensive.
09:07 PM XXCoder: whoa thats whole level above what we run lol
09:07 PM Thorhian: Ceramic? Were you milling Inconel?
09:07 PM norias: well, they were turning hardened steel rolls
09:07 PM norias: for steel mills
09:07 PM Thorhian: Ah I see.
09:07 PM XXCoder: thor that same blackout killed one part I was running also, by dropping a little bit while it was milling high precsion hole. it made those $500 seem cheap
09:07 PM XXCoder: i think there is insurance for such lol
09:08 PM norias: these things were in the multiple tons per part
09:08 PM norias: i think 120 tons was the max the cranes could lift
09:08 PM XXCoder: wow
09:08 PM norias: most were < 80 tons
09:08 PM XXCoder: we dont deal with tons lol
09:08 PM norias: because if it was over 80 tons, you had to get a specific crane
09:08 PM XXCoder: largest parts we run is 1'x2'x6'
09:09 PM XXCoder: alum, heavy but not tons
09:09 PM norias: i have photos...
09:09 PM norias: of like, this one bridge mill
09:09 PM norias: the operator was sitting on a lawn chair
09:09 PM norias: on the table, while machining a part
09:09 PM norias: the table was like 30
09:09 PM Thorhian: Lol you guys are milling crazy stuff. I just want to make cases and do dye work for jewellery for now.
09:09 PM norias: 30' x 40'
09:10 PM norias: i think it had 20' under the spindle
09:10 PM norias: and the face mills were about 3' diameter
09:10 PM Thorhian: Holy crud...
09:11 PM norias: when i was last there, they were milling this huge casting
09:11 PM norias: it was the side of a rolling mill
09:11 PM XXCoder: sitting in milling machine table, that'd be death for any machine at work I go to ;)
09:11 PM norias: well, a stand in a rolling mill
09:13 PM Thorhian: XXCoder: Would that indexable end mill I linked be decent for a home shop or should I look elsewhere? If I can do roughing/pocket roughging then that's great.
09:13 PM XXCoder: im not sure, i dont buy tools at work and I dont have machine big enough to can use those at home lol
09:14 PM XXCoder: so i work at too big and too small scale at same time :P
09:14 PM Thorhian: XD What the biggest tools you use at home XXCoder ?
09:14 PM XXCoder: umm 1/4 I think. max for er11
09:14 PM XXCoder: not that my routers been working for while. cant work on it till i have shop
09:15 PM Thorhian: Oh lol. My spindle has a BT30 taper, and I'm using ER32 primarily.
09:15 PM XXCoder: cool :)
09:15 PM Thorhian: I can't wait to get it built :D Thank you. I ordered my RPi4 and Mesa Boards yesterday.
09:16 PM XXCoder: honestly 27 usd isnt too bad
09:16 PM Thorhian: Just have to wait for my rails and find the steel I need.
09:17 PM Thorhian: I figured 27 wasn't bad, and APKT 1003 inserts seem to be pretty cheap.
09:17 PM XXCoder: theres endmills thats designed specifically for plunging too
09:18 PM XXCoder: its made bit differently, and it can cut material all way to center
09:19 PM Thorhian: I mean, as long as I can do some pockets I don't mind just using normal end mills and indexable shoulder mills.
09:20 PM XXCoder: yeah and theres various methods to do so
09:20 PM XXCoder: depends on what is being done
09:20 PM _unreal_: GOD THE amd graphics driver is a TOTAL pain in the ass
09:20 PM XXCoder: for example, mill down bore by indexable mill then using regular endmill to finish up clean surfaces
09:21 PM Thorhian: Lol what _unreal_ ? Are you in windows or an ancient linux kernal?
09:21 PM XXCoder: or maybe just use single endmill do everything but it will affect tool life expecially if harder material
09:21 PM XXCoder: amd sucks
09:22 PM Thorhian: My Vega 56 works like a dream in Arch. *shrug* I hate Nvidia and I don't like CUDA lol
09:22 PM _unreal_: thorhian I have a FREE computer I got
09:22 PM _unreal_: and I'm reloading windows onto is
09:22 PM _unreal_: I am a linux user mainly
09:22 PM Thorhian: What is the GPU?
09:23 PM _unreal_: some amd dual core one of those computer builtinto the motor things
09:23 PM Thorhian: Oh, so it's a AMD CPU with builtin graphics (an AMD APU)?
09:24 PM _unreal_: ya
09:24 PM _unreal_: I work on luxury boats etc..
09:25 PM _unreal_: and they throw a lot of expensive shit away
09:25 PM _unreal_: Ipulled some HP all in one out of the trash few weeks ago NOTHING wrong with it
09:25 PM XXCoder: did you clean hd squeaky clean?
09:25 PM XXCoder: might have some sick stfuf
09:25 PM _unreal_: amd e1-1500
09:25 PM Thorhian: I'm guessing you already looked up the specific model number and downloaded the drivers directly from AMD's website?
09:26 PM Thorhian: model of APU*
09:27 PM _unreal_: I'm just trying to get everything setup on it
09:27 PM _unreal_: it has 6gb ram
09:27 PM Thorhian: You were complaining about AMD Graphics drivers, hence my recomendation.
09:28 PM _unreal_: ?????I said there WEBSITE sucks
09:29 PM XXCoder: when?
09:30 PM Thorhian: XXCoder: I'm guessing that the indexable end mill can easily rough out the inside of this case as an example of what I am looking to do: https://cdn.shopify.com/s/files/1/1473/3902/products/86d6b6668dd249b94188acb64812e4bf_1475cf00-f633-43b5-9d26-9015772952d7_1800x1800.jpg?v=1584436596
09:30 PM XXCoder: yep. what material?
09:30 PM Thorhian: Aluminum.
09:30 PM XXCoder: leave say .05" all around
09:30 PM Thorhian: I would but inserts for aluminum.
09:30 PM XXCoder: then finish it off with endmill
09:30 PM Thorhian: Yeah, that would be the plan. I don't think any predrilling would be needed would it?
09:30 PM XXCoder: if youre confient, leave just .02"
09:31 PM dirty_d: Thorhian, what kind of machine do you have?
09:31 PM XXCoder: not at all use a endmill at radius you want
09:32 PM norias: yuck
09:32 PM norias: so, i'd warn against leaving too little stock for cleanup
09:33 PM XXCoder: yup!
09:33 PM norias: do the math
09:33 PM Thorhian: I am accumulating parts to build one at the moment dirty_d . Just trying to learn about what the uses of different cutting tools are ATM.
09:33 PM norias: the less stock the faster the feeds required to have the same chip load
09:33 PM XXCoder: work we could leave some stock, mill it down leaving very small amount of stock left then mill with seperate endmill to finish it to size
09:33 PM XXCoder: but sometimes simply direct from rough then mill to size
09:34 PM norias: i.e. chip loads in tables, etc are only accurate for the case of 50% or greater radial chip load
09:34 PM XXCoder: im not guy who makes programs for machines so I dont know how decision process is
09:34 PM dirty_d: Thorhian, like from scratch? I thought about that
09:34 PM norias: 50% or greater radial depth of cut, i mean
09:34 PM norias: in that case chip load = feed per tooth
09:34 PM XXCoder: Thorhian: ATC machine?
09:35 PM norias: anything less than 50%, you have to go faster to achieve same chip load
09:36 PM Thorhian: I have been designing it based on several designs I've seen around dirty_d, but yeah, no pre-existing mill.
09:36 PM dirty_d: getting everything square and all seems very hard
09:37 PM norias: getting what square?
09:37 PM XXCoder: machine
09:37 PM dirty_d: when I built my router i just pretended everything was perfectly square and its worked out so far
09:37 PM Thorhian: XXCoder: The spindle has a BT30 taper, but no automatic system for changing tools. I'll be using an M12 threaded rod to hold the tool holders for now before I get an air powered pull stud grabber.
09:37 PM dirty_d: its close enough to not matter for the stuff ive been doing
09:37 PM XXCoder: thats still quite repeatable
09:37 PM _unreal_: HP 1155
09:38 PM XXCoder: so you can have holes wood block for example, labeled with numbers
09:38 PM XXCoder: so you can measure em all and setup
09:38 PM dirty_d: norias, like having all the axes perfectly perpendicular
09:38 PM norias: oh, yeah, pain in the dick
09:38 PM norias: don't forget gravity
09:38 PM dirty_d: Thorhian, did you get that one that I've seen on ebay?
09:39 PM XXCoder: i do suggest you to make "probe" tool that is simply one of those bt30, but with long taper tool holder then hold a nice high precision rod
09:39 PM XXCoder: it can be used as common reference
09:39 PM Thorhian: The green ones dirty_d? Yes.
09:39 PM dirty_d: those look beefy
09:40 PM Thorhian: I have it right next to me lol. It is fairly beefy and it doesn't even have a motor on it XD
09:40 PM XXCoder: ie use holder on rock measure top of holder then top of that "probe", you touch it on top of whatever surface that should be zero, then you subtract the length from z
09:40 PM XXCoder: for tools you just measure from holder to end of tool and input those
09:41 PM Thorhian: My current test indicator can only indicate to half a thousanth, and it the spindle's runnout can't be fully described with it, so I am happy for my purposes.
09:42 PM Thorhian: Thank you XXCoder, sounds good.
09:43 PM XXCoder: its also nicely set, if you break the "probe" you can simply make new one. it can be different length it dont matter
09:43 PM XXCoder: since true referece point is the machine
09:44 PM Thorhian: This is the spindle I got dirty_d: https://www.ebay.com/itm/254532653736
09:44 PM Tom_L: you got it already?
09:44 PM Thorhian: Yep.
09:44 PM Tom_L: quality?
09:45 PM dirty_d: What are you gonna drive it with?
09:45 PM Tom_L: a hampster cage
09:45 PM Thorhian: xD
09:45 PM XXCoder: you need the holder for measuring though. just use thick rod of metal, use lathe make cone in it, make sure its sized so bt30 dont "bottom out", turn it around and clean up bottom
09:45 PM _unreal_: Thorhian, I'd drive that with one big ass brushless motor
09:45 PM XXCoder: need bore though it so pull tabs dont hit it
09:45 PM Thorhian: It seems good so far. Won't truly know until I use it in the machine.
09:45 PM _unreal_: give you lots of power and lots of speed control
09:46 PM Thorhian: dirty_d: I already have a 1800W BLDC motor and power supply for it in the mail.
09:46 PM Thorhian: Already ahead of you _unreal_
09:46 PM dirty_d: hmm, is that enough?
09:47 PM _unreal_: o,O how is 1800 watt not enough
09:47 PM Thorhian: Yeah, for my needs dirty_d.
09:47 PM dirty_d: you can get very very powerful brushless RC motors for pretty cheap
09:47 PM _unreal_: dirty_d, you know how much that head is geared down ya?
09:47 PM dirty_d: _unreal_, no gearing I don't think
09:47 PM Thorhian: _unreal_: THe spindle isn't geared down.
09:47 PM _unreal_: ? I thought you got a gear reduction
09:48 PM Thorhian: The 7:24 ratio in the descriptions was describing the taper.
09:48 PM dirty_d: I have a 6000W RC motor waiting to be used for something it's not meany for
09:49 PM _unreal_: ahh
09:49 PM _unreal_: so its just auto tool changer and no gear down
09:49 PM _unreal_: dirty_d, the motor he ordered is rated for more then that head unit that unit is rated for 1.5kw
09:49 PM Thorhian: I didn't go too crazy with the motor because they technically only rate the spindle for 1.5kW, and how do you power a 6000W RC motor without relying on batteries in a normal garage lol?
09:49 PM dirty_d: I think you gotta figure that part out yourself
09:49 PM XXCoder: very very large solar arrays? ;)
09:50 PM Thorhian: Lol XXCoder.
09:50 PM _unreal_: hamster wheel
09:50 PM dirty_d: looks like the bare minimum, two pieces of steel and bearings
09:50 PM _unreal_: and a drawbar
09:50 PM dirty_d: well, cast iron
09:50 PM dirty_d: oh it comes with a drawbar?
09:50 PM Thorhian: I had a hard enough time find a DC power supply at 48v for this motor.
09:51 PM Thorhian: No drawbar with this spindle.
09:51 PM _unreal_: Thorhian, its called aliexpress
09:51 PM _unreal_: Thorhian, you ordered a motor brushless right
09:51 PM _unreal_: does it come with a VFD?
09:51 PM dirty_d: Thorhian, powering it has been what's stopped me from using it for anything yet
09:52 PM _unreal_: dirty_d, he doesnt have a working frame so far as I know still as well
09:52 PM Thorhian: Lol and Banggood _unreal_, that is where I found my powersupply. I have to have a new electrical subpanel to put in another 220v line for the powersupply.
09:52 PM dirty_d: 36V at 180A is inconvenient
09:52 PM _unreal_: Thorhian, did you order a VFD?
09:52 PM Thorhian: _unreal_: VFDs aren't used for BLDC motors, even if BLDC motors and 3 Phase AC motors are similar in principle.
09:52 PM _unreal_: AHH 36V 180a IS WAY OVER 1.8kw
09:53 PM Thorhian: And yes, my motor for the spindle is a Brushless motor.
09:53 PM dirty_d: mines 6000W, or 6500W
09:53 PM _unreal_: omg...
09:53 PM _unreal_: Thorhian, did you order or does it come with a VFD?
09:53 PM _unreal_: YES OR NOW
09:53 PM _unreal_: no
09:53 PM Thorhian: Lol it's a 36V BLDC motor dirty_d ? XD Find a different motor.
09:54 PM Thorhian: You don't buy VFDs for BLDC motors unreal.
09:54 PM Thorhian: You need a specific BLDC controller.
09:54 PM Thorhian: And yes, mine came with one.
09:55 PM _unreal_: vfd is for brushless and AC induction motors
09:55 PM Thorhian: https://en.wikipedia.org/wiki/Variable-frequency_drive
09:55 PM dirty_d: https://photos.app.goo.gl/QSRrTUKQSAJt6BRq8
09:55 PM Thorhian: VFD is a term used specifically for AC 3 Phase motors.
09:55 PM dirty_d: doesn't look like it should be that powerful
09:55 PM _unreal_: Thorhian, do you have the model number for the VFD You have?
09:55 PM _unreal_: Thorhian, BLDC is 3phase motor
09:55 PM Thorhian: No unreal.
09:56 PM Thorhian: BLDC is a DC motor. Not an AC motor, but that are nearly identical.
09:56 PM Thorhian: they*
09:56 PM dirty_d: I wouldn't really call a VFD a brushless controller
09:56 PM dirty_d: they just output three phase at variable frequency with no feedback
09:57 PM _unreal_: Thorhian, google this " is a bldc a 3 phase motor "
09:57 PM dirty_d: for brushless you need the same, but synchronized with the rotor
09:57 PM Thorhian: VFD's are specifically for 3-Phase AC motors. A brushless 3-phase motor may have 3 phases, but it isn't driven with AC current.
09:57 PM _unreal_: and DONT tell me I dont know what I'm talking about I've been building CNC machines since 1999
09:57 PM _unreal_: Thorhian, they are diriven in different directions also known as AC
10:01 PM _unreal_: https://www.motioncontroltips.com/faq-whats-the-difference-between-bldc-and-synchronous-ac-motors/
10:01 PM _unreal_: RIGHT THERE
10:01 PM _unreal_: read
10:01 PM _unreal_: you will notice the BLDC shows a sign wave +/- wave form that is positive and negative direction power
10:02 PM _unreal_: hence BLDC motors are often refered to as ac motors
10:02 PM Thorhian: Reading this only confirms my opinion. Calling a BLDC motor similar to a 3 phase _AC_ motor would be apt, but they aren't exactly the same thing.
10:03 PM _unreal_: The REASON I asked about the VFD is depending on the version it may have its PSU built in and you dont need an exteranl power supply
10:03 PM _unreal_: typically VFD's just run off 110/220
10:03 PM Thorhian: Nope, no PSU.
10:04 PM _unreal_: ? DC supply VFD's are not common at all.
10:04 PM _unreal_: what is the model
10:04 PM _unreal_: not common at all at all
10:04 PM _unreal_: very wasteful for power
10:04 PM _unreal_: do you know the model of the VFD
10:05 PM Thorhian: It's a brushless controller that came with the motor, not sure of the exact model. It was originally a kit to retrofit motor bikes to be electric.
10:07 PM Thorhian: Also, you are basically saying that all of the ESC's used in various products like quadcopters are VFDs and claiming that they are uncommen when in reality they are very common.
10:09 PM _unreal_: I'm talking high power
10:10 PM _unreal_: quad copters and RC devices push massive current
10:10 PM _unreal_: low voltage
10:11 PM Tom_L: do those motors last though?
10:11 PM _unreal_: https://drive.google.com/open?id=0B3vL4RqyNgQAQ29zSkpJRUZ6ZkE https://drive.google.com/open?id=0B3vL4RqyNgQAcW05dWktU2JoWjQ https://drive.google.com/open?id=0B3vL4RqyNgQAVTFPT3UwVEF6S2s
10:11 PM Tom_L: or do they burn em up quick
10:11 PM _unreal_: lol
10:11 PM _unreal_: tom
10:11 PM Thorhian: It probably depends Tom, but without proper cooling then probably not. Those things do push a lot of air though.
10:11 PM _unreal_: Thorhian, there is a HUGE difference between industrial and MODEL
10:12 PM Tom_L: i know the drag rc cars didn't last too long
10:12 PM Thorhian: Maybe in wattage used and the need to beef up the motors to handle larger amounts of voltage and current unreal, but the underlying principles are the same.
10:12 PM _unreal_: Thorhian, I build very expensive racing quads and camera platforms all kinds of CUSTOM
10:12 PM _unreal_: I know RC and bldc etc.. inside and out
10:13 PM _unreal_: true an ESC and VFD are more or less the same thing
10:14 PM Thorhian: They may be very similar but they aren't the same thing, hence my claim earlier.
10:14 PM _unreal_: but a VFD is an industrial device designed with a LARGE MTF where as the RC industry is not designed for endless hours of operation
10:14 PM Thorhian: Hence why I don't call BLDC controllers VFDs.
10:14 PM _unreal_: "<Thorhian> Also, you are basically saying that all of the ESC's used in various products like quadcopters are VFDs and claiming that they are uncommen when in reality they are very common."
10:14 PM _unreal_: now your making shit up
10:14 PM _unreal_: o,O
10:14 PM _unreal_: OHH BOY
10:15 PM Tom_L: here goes the neighborhood
10:15 PM Thorhian: "Thorhian | BLDC is a DC motor. Not an AC motor, but that are nearly identical."
10:16 PM _unreal_: and that is not true. they are an Ac MOTOR using dc current
10:16 PM * Tom_L goes to bed before it gets any worse
10:16 PM _unreal_: hehe
10:16 PM _unreal_: later Tom_L
10:16 PM XXCoder: later tom
10:17 PM Thorhian: THey are using a PWM signal that basically mimics an AC signal.
10:17 PM _unreal_: PWM has NOTHING to do with AC
10:17 PM _unreal_: PWM has to do with duty cycle
10:17 PM _unreal_: current
10:17 PM _unreal_: POWER
10:17 PM _unreal_: think of it like a light dimmer
10:18 PM Thorhian: Also, good night Tom. And _unreal_, I don't think you are changing my mind on this, at least right now. It's getting late here for me to.
10:18 PM Thorhian: too*
10:18 PM _unreal_: to change the speed of a brushless you have to change two things. the stepping frequency. and the current. and the current is based on PWM
10:18 PM Tom_L: light dimmers rely on zero crossing to switch
10:19 PM _unreal_: PWM has NOTHING to do with the speed of the motor. the motor speed is based on the stepping frequency
10:19 PM _unreal_: Tom_L, no kidding
10:19 PM _unreal_: I'm refering to curent control
10:19 PM Tom_L: no i'm not kidding :)
10:20 PM _unreal_: its offical thorhian is a dumb ass
10:20 PM Tom_L: naw
10:20 PM Tom_L: we don't wanna go there
10:20 PM _unreal_: a while ago he was arguing with someone else over...
10:20 PM _unreal_: ahh...
10:21 PM _unreal_: crap what was it. VERY FOOLISH ARGUMENT
10:21 PM Tom_L: not like that hasn't happened here before
10:21 PM _unreal_: heh
10:21 PM _unreal_: <Thorhian> THey are using a PWM signal that basically mimics an AC signal.
10:22 PM _unreal_: thats a clear example of not understanding the hardware at all
10:22 PM dirty_d: you guys just weren't understanding each other, lol
10:22 PM Tom_L: so he didn't explain it quite right
10:22 PM Tom_L: in his mind i think he knows
10:22 PM _unreal_: not quite right LOL !!!!!!!
10:23 PM Tom_L: you can either help someone or you can argue with them and if they don't accept the help walk away
10:23 PM _unreal_: hay look.. * Thorhian has quit (Quit: WeeChat 2.8) he walked a way ;)
10:23 PM _unreal_: ehheheh
10:23 PM Tom_L: he went to bed
10:24 PM unterhaus: Tom_L you got a kernel running? 4.18?
10:24 PM _unreal_: ya true
10:24 PM Tom_L: i sure do
10:24 PM Tom_L: 4.19.114
10:24 PM Tom_L: i think
10:24 PM unterhaus: okay
10:24 PM unterhaus: any tricks?
10:24 PM Tom_L: oh got yes
10:24 PM Tom_L: god
10:24 PM _unreal_: I got my controller box MUCH closer this weekend
10:24 PM unterhaus: uh oh
10:24 PM _unreal_: I could have gotten a lot more done but I spent a good chuck of time throwing out shit
10:24 PM Tom_L: it's not too bad but there are a couple ways to go about it
10:25 PM _unreal_: cleaning and trying to find the @$#$#$ chips I'm missing
10:25 PM Tom_L: i'm not gonna get into that tonight
10:25 PM unterhaus: Tom_L, did you take notes?
10:25 PM Tom_L: of course
10:25 PM Tom_L: all in my brain
10:25 PM Tom_L: and a couple on paper
10:25 PM unterhaus: okey, well I'll try it and bug you a lot some other time
10:26 PM _unreal_: Tom_L, no alcohol for you. dont need to erase any memories
10:26 PM Tom_L: i started with a pure clean buster install from the debian iso
10:26 PM Tom_L: naw i don't drink anymore
10:26 PM Tom_L: and by the way, that RTAI isn't workable yet
10:27 PM unterhaus: so yours is preempt?
10:27 PM Tom_L: no i installed RTAI but it's got a bug
10:27 PM Tom_L: i can boot either one
10:27 PM unterhaus: okay
10:27 PM Tom_L: i installed both
10:27 PM unterhaus: how bad is the bug?
10:27 PM Tom_L: then i built linuxcnc
10:28 PM Tom_L: crashes on andy after maybe 2-300 iterations
10:28 PM Tom_L: about the same for me
10:28 PM Tom_L: my gigabyte i5 went over 3000 iterations before it locked up
10:29 PM Tom_L: incidentally, the preempt-rt kernel passed on both machines i tested it on
10:29 PM Tom_L: the test was to try and narrow down the bug but i'm not sure it did
10:29 PM Tom_L: some memory leak somewhere i think
10:29 PM unterhaus: guess I'm using the i5 then, seems to run preempt okay
10:30 PM Tom_L: you gonna run buster?
10:30 PM unterhaus: I don't know, probably mint actually, seems to work
10:30 PM Tom_L: https://gnipsel.com/linuxcnc/uspace/linuxmint19-rt.html
10:30 PM skunkworks: Preempt with the right computer will do close to 40khz..
10:31 PM skunkworks: (like a 3rd gen i5)
10:31 PM Tom_L: https://gnipsel.com/linuxcnc/uspace/debian9-rt.html
10:31 PM Tom_L: if you decide to try buster, that should get you close
10:31 PM Tom_L: skunkworks, what servo thread are you running on the pi?
10:32 PM skunkworks: 500hz
10:33 PM Tom_L: what's that in ns?
10:33 PM Tom_L: i'm tired...
10:33 PM skunkworks: heh
10:33 PM skunkworks: 2000000
10:33 PM Tom_L: thanks
10:33 PM skunkworks: is that right? It is late here too
10:33 PM Tom_L: hopefully i can remember most of this by the weekend
10:33 PM Tom_L: board should be here by then i hope
10:33 PM skunkworks: if your doing spi - you can probably get by with 1khz
10:34 PM skunkworks: I think ethernet has a bit higher overhead
10:34 PM Tom_L: i didn't change my config from the parallel port when i tested the 7i80
10:34 PM CaptHindsight: skunkworks: did you see that somebody go the microcontroller in the Allwinner ARM SOC to software step at up to 400KHz
10:34 PM skunkworks: nice
10:34 PM skunkworks: !
10:35 PM skunkworks: CaptHindsight: link?
10:35 PM CaptHindsight: so software stepping on the Rpi GPIO header
10:35 PM Tom_L: huh
10:35 PM CaptHindsight: https://cnc32.ru/orangecnc/
10:35 PM CaptHindsight: he also posted on the forum
10:35 PM Tom_L: well they do it with grbl on an avr
10:36 PM CaptHindsight: https://forum.linuxcnc.org/18-computer/39037-linuxcnc-orange-pi#166968
10:36 PM Tom_L: alot less overhead there though
10:37 PM CaptHindsight: Tom_L: the allwinners have 2-8 arm cores to run LCNC
10:37 PM unterhaus: some local guys were doing 750ipm with steppers using mendel
10:37 PM CaptHindsight: and also an embedded controller that you can use for software stepping
10:37 PM Tom_L: sounds somewhat like the old 68332
10:38 PM CaptHindsight: Steps rate now very high (up to 1 MHz)
10:38 PM CaptHindsight: like the BBB only with a GPU that works
10:38 PM CaptHindsight: machinekit should have used these
10:39 PM CaptHindsight: but i think someone worked for TI
10:39 PM dirty_d: skunkworks, why'd you decide on 500Hz?
10:39 PM CaptHindsight: on that team
10:40 PM CaptHindsight: stinking Allwinner used an open RISC core in their devices and didn't share that info
10:40 PM unterhaus: beagleboards was Ti affiliated I thought
10:40 PM CaptHindsight: https://linux-sunxi.org/AR100
10:41 PM unterhaus: machinekit is architecture agnostic, just like linuxcnc
10:41 PM CaptHindsight: unterhaus: yes, but the core devs of machinekit might of had a TI employee
10:42 PM unterhaus: If you are talking about Charles, I think he's just really good
10:42 PM CaptHindsight: unterhaus: they wrote some specific code for the PRU's
10:42 PM CaptHindsight: Zultron (sp)
10:42 PM CaptHindsight: think his name was John
10:42 PM unterhaus: dunno, I thought a lot of that was Charles S.
10:43 PM unterhaus: not going to try to spell his last name without looking
10:43 PM CaptHindsight: could of had software stepping and a working GUI
10:43 PM unterhaus: okay, bread should be ready to bake
10:44 PM unterhaus: the allwinner is very similar in that sense, has to have a driver
10:44 PM skunkworks: dirty_d: because it didn't do 1khz..
10:45 PM dirty_d: hmm, what happened? I'm using an rpi 4 with an ethernet mesa card at 1kHz
10:45 PM skunkworks: dirty_d: no realtime delays?
10:46 PM dirty_d: I haven't gotten any errors
10:46 PM skunkworks: it was at the edge.. I haven't tried 1khz in a while.
10:46 PM dirty_d: I wonder what the difference could be
10:46 PM skunkworks: dirty_d: did you do anything fancy? isolcpus? idle=poll? stuff like that?
10:47 PM skunkworks: dirty_d: what mesa hardware?
10:47 PM dirty_d: I used the arguments that were on the page linked in the thread where you posted those videos
10:47 PM dirty_d: 7i96
10:47 PM dirty_d: no wifi
10:48 PM dirty_d: I'm using a usb ethernet adapter for internet
10:48 PM skunkworks: I am running wifi. I am also using things like smart serial and stuff.
10:48 PM skunkworks: I can re-visit 1khz..
10:49 PM skunkworks: dirty_d: have you tried running youtube at the same time?
10:49 PM skunkworks: (just wondering what it would do)_
10:50 PM dirty_d: ive never run it at the same time as linuxcnc, but I did while doing the latency test
10:50 PM dirty_d: when I'm actually using linuxcnc, i have nothing else opened except a terminal
10:50 PM CaptHindsight is now known as BigElectricCat
10:50 PM dirty_d: or a text editor
10:51 PM skunkworks: sure.. That is how I 'normally' run it ;)
10:53 PM dirty_d: did you actually get youtube videos to play smoothly?
10:53 PM dirty_d: I didn't
10:54 PM dirty_d: choppy as hell
10:55 PM Tom_L: skunkworks, do you use their imager to transfer jepler's .img file to the sd then install it there?
10:55 PM dirty_d: I wonder if arch linux arm would perform better
10:56 PM dirty_d: I think it's compiled specifically for Armv8
10:56 PM dirty_d: raspbian is armv6 isn't it, to be compatible with the original raspberry pi?
10:56 PM Tom_L: i've no clue
11:00 PM unterhaus: sometimes, compiling for the right processor makes a big difference
11:07 PM unterhaus: I shouldn't have started making bread this late
11:08 PM unterhaus: it's really ugly looking too, hopefully I didn't kill off the yeast this time
11:09 PM BigElectricCat: late night baking
11:20 PM unterhaus: I guess it's not a horrible idea
11:31 PM skunkworks: Tom_L: I extract the img from the zip then dd it to the sd
11:32 PM skunkworks: something like o
11:32 PM skunkworks:
11:32 PM skunkworks:
11:32 PM skunkworks: 3:08
11:32 PM skunkworks: NOW PLAYING
11:32 PM skunkworks:
11:32 PM skunkworks: YOUR Dirty Forking Tips!
11:33 PM skunkworks: AvE
11:33 PM skunkworks: 61K views
11:33 PM skunkworks: 5 hours ago
11:33 PM skunkworks:
11:33 PM skunkworks:
11:33 PM skunkworks: 26:06
11:33 PM skunkworks: NOW PLAYING
11:33 PM skunkworks:
11:33 PM skunkworks: Mark Hamill on William Shatner Beef, Fate of Luke Skywalker and Connection to John Boyega
11:33 PM skunkworks: SWAY'S UNIVERSE
11:33 PM skunkworks: 508K views
11:33 PM skunkworks: 2 years ago
11:33 PM skunkworks:
11:33 PM skunkworks:
11:33 PM skunkworks: 32:02
11:33 PM skunkworks: NOW PLAYING
11:33 PM skunkworks:
11:33 PM skunkworks: The hole won't win again: Macbook board DEFEATED and data recovered.
11:33 PM skunkworks: Louis Rossmann
11:33 PM skunkworks: 75K views
11:33 PM skunkworks: 3 days ago
11:33 PM skunkworks:
11:33 PM skunkworks: wow
11:34 PM skunkworks: sudo dd bs=4M if=~/Downloads/2020-01-08-linuxcnc-pi4-full.img of=/dev/mmcblk0 conv=fsync
11:34 PM skunkworks: is what I ment
11:34 PM XXCoder: not as bad as me pasting entire long wiki page, thankfully hechat buffers input so I could exit to stop the spam
11:36 PM skunkworks: i guess you know what kind of videos youtube pushes to me
11:36 PM XXCoder: lol