#linuxcnc Logs

Feb 14 2019

#linuxcnc Calendar

01:36 AM Loetmichel: *ROFL* Ebay-aluminium-seller is absolved... Error was in front of keyboard, as always... *Note to self: When changing VFDs: double check that the Spindle phases are correctly sequenced... Spindle ran in reverse. No wonder it melted and chattered instead of cutting. Just strange that it removed material AT ALL!
01:50 AM gloops: did you manage to get the spindle going the right way Loetmichel?
01:50 AM Loetmichel: gloops: of course. just had to switch two phase wires
01:50 AM sensille: btw, i got aluminum from motedis and it is nicely flat
01:51 AM Loetmichel: still: didnt notice the wrong spin direction all day yesterday
01:51 AM sensille: "somehow this sound different. must be the VFD."
01:52 AM gloops: im useless with those situations, press run and some disaster is unfolding before my eyes - i just stand watching it instead of pressing stop
01:53 AM sensille: oh, i know that feeling
01:53 AM sensille: just gawking
01:56 AM Loetmichel: sensille: i tried everything, resharpening tools, different speeds, different feeds, different tools... no avail.. i concluded it must have been Al99.9 instead of AlMg4.5Mn because "reinalu" behaves similar with spindle in forward.
01:57 AM Loetmichel: at 24kRPM you just dont notice that the spindle is turning the wrong way
01:57 AM sensille: and you felt really stupid when you found out, eh?
01:58 AM Loetmichel: indeed
01:59 AM Loetmichel: drove to the company this morning, had an epiphany... "what if the spindle runs backwards?"... got here, didnt even get rid of my coat, booted the CNC mill, started the spindle on low RPM: "yes, wrong direction..."
01:59 AM gloops: a habit ive got is to just click the spindle on and let it run slow for a bit while im setting up - just to let it warm it a bit, then again i still wouldnt have nopticed it going the wrong way lol
02:00 AM CaptHindsight: similar incident here with a hacksaw
02:00 AM CaptHindsight: put the blade in backward
02:01 AM gloops: my old teacher told me that the teeth should face back with a hand hacksaw, had no end of arguments over that over the years
02:02 AM gloops: japanese wood saw blades cut on the back stroke
02:04 AM Loetmichel: european hacksaws usually cut on the forward stroke, asian saws on the back stroke
02:04 AM Loetmichel: i know.
02:04 AM Loetmichel: been there done that ;)
02:12 AM Deejay: moin
02:13 AM sensille: Loetmichel: as you know everything :) can you recommend a compressor?
02:17 AM Loetmichel: depends on what you want to do
02:19 AM sensille: blow things clean
02:19 AM sensille: so nothing fancy
02:20 AM Loetmichel: cheapest mobile one with integrated tank on Ebay. If you want to do "squeaky clean" get an air dryer for it
02:21 AM sensille: "cheapest one" is a recommendation i like :)
02:23 AM Loetmichel: https://www.ebay.de/itm/DruckluftKompressor-50L-2PS-Luftdruck-Kompressor-8-Bar-OPT-13tlg-Druckluft-SET/351920906754 something like this
02:25 AM Loetmichel: https://www.ebay.de/itm/Zerodis-1-4-Luftkompressor-Filterregler-Wasserdruck-Feuchtigkeitsfalle-Ol-Se/323687765252 <- add that if you need really "clean" air
02:25 AM sensille: fancy :) thanks
02:43 AM gloops: hmm, i wonder if one of those cheapo tyre inflators would be ok for that
02:44 AM gloops: probably not it takes an hour to blow a tyre up lol
02:45 AM Loetmichel: gloops: no tank
02:45 AM Loetmichel: so no, not ok
02:47 AM Loetmichel: sensille: if you are into self building things: get a "kühlschrankei", a fire extinguisher and that water seperator/regulator and mount them
02:47 AM Loetmichel: or just buy am airbush compressor with tank if you want "quiet" and dont need much air/long time high volume
02:48 AM sensille: "kühlschrankei"? no idea what that might be :)
02:49 AM gloops: ive got a big rand compressor but rarely used, its not worth messing if you just want a squirt of air
02:50 AM Loetmichel: sensille: the compressor of a fridge
02:50 AM sensille: but you want a squirt of air from time to time?
02:50 AM pink_vampire: hi
02:51 AM gloops: sensille i do but i dont want to wait for a tank to fill, it also sounds like a V8 engine
02:51 AM gloops: hi pink_vampire ltns
02:51 AM pink_vampire: yeah, I know
02:51 AM Loetmichel: sensille: https://gastrotiger.de/userdata/mysydeshop/images/normal/1_605166.jpg <- its formed like an egg, hence the nickname
02:52 AM gloops: a permanent air line to the spindle is good when cutting ally
02:52 AM sensille: gloops: yeah, quiet might be nice, but you probably pay for that
02:52 AM Loetmichel: and you get them cheap out of old fridges if you have access to a recycling center
02:53 AM gloops: they use the fridge/tyre inflators a lot in various hacks for de-gassing silicone, you can fill a tank slowly with them
02:53 AM Loetmichel: gloops: i once made an air compressor out of an 1,6 liter "golf gti" engine..
02:53 AM Loetmichel: not quite V8 sound, but it was FAST to fill the 200L air tank ;)
02:53 AM Loetmichel: (it had a 60kW three phase motor on it though)
02:54 AM gloops: might be a bit of overkill Loetmichel lol
02:54 AM sensille: gloops: air line to the spindle or to the endmill?
02:54 AM gloops: sensille well to the cutter yes, blow the chips out
02:54 AM sensille: i want to suck the chips in instead
02:55 AM sensille: blowing them around the room would be a mess
02:55 AM Loetmichel: gloops: blowing chips away is exactly what got me into that CNC mill predicament yesterday
02:55 AM gloops: vacuum is trickier than blowing
02:55 AM Loetmichel: coworker managed to blow the chips into the VFD and shorted it out
02:55 AM pink_vampire: I have the Kobalt compressor and it is inside mt home and the vacuum is much much more noisy then the compressor
02:55 AM gloops: its not about collecting the chips, but removed them from the cut, they need blasting out
02:56 AM pink_vampire: this one https://www.lowes.com/pd/Kobalt-Quiet-Tech-4-3-Gallon-Portable-Electric-Twin-Stack-Air-Compressor/1000125721
02:56 AM sensille: i see. so blast them into the vacuum :)
02:56 AM gloops: you can blast them towards the suction yes
02:56 AM gloops: chip clearance important
02:56 AM rmu: Loetmichel: if chips can get into a VFD they will
02:56 AM rmu: sooner or later
02:56 AM Loetmichel: rmu: took 6 years
02:57 AM Loetmichel: and yes, it WAS mounted a bit precarious... -> http://www.cyrom.org/palbum/main.php?g2_itemId=17171&g2_imageViewsIndex=1
02:57 AM Loetmichel: coworker had an impeccable aim though ;)
02:58 AM sensille: gloops: and build some "enclosure" with something like this: https://images-na.ssl-images-amazon.com/images/I/61zymsfQEoL._SX355_.jpg
02:58 AM gloops: air blow kit for ally https://www.youtube.com/watch?v=O2ijiWtT9OE
02:59 AM gloops: hmm you could have a chip collection shoe on
03:00 AM gloops: that one looks ok pink_vampire posted
03:01 AM rmu: Loetmichel: IME alu chips fly 2m and more if i remove the dust shoe
03:01 AM pink_vampire: someone know if linux cnc support 2 motors from each corner?
03:02 AM sensille: gloops: but mounted with Z independant of the spindle
03:02 AM pink_vampire: https://www.kickstarter.com/projects/1830738289/maslow-cnc-a-500-open-source-4-by-8-foot-cnc-machi/posts/1826750
03:03 AM pink_vampire: something like that
03:04 AM rmu: pink_vampire: it is possible, you probably have to write your own kinematics
03:04 AM CaptHindsight: replace router with hungry beavers
03:05 AM CaptHindsight: or make it more organic...
03:05 AM gloops: with a 6040 id enclose the whole machine, miles better, quieter, mess contained, you could watch TV at the side of that while it was running
03:05 AM sensille: ok, i definitely need a dust shoe
03:05 AM CaptHindsight: replace router with termites
03:05 AM pink_vampire: rmu: is there a name to that type of kinematic?
03:07 AM rmu: pink_vampire: i know of a project where such a setup was used to spray walls, it had kind of automated spray can instead of router. there should be a hackaday article about it. don't remember name of kinematics
03:07 AM CaptHindsight: quadratic trapeze
03:08 AM CaptHindsight: what if you flip the plywood 90 deg and use a spring vs gravity?
03:09 AM CaptHindsight: or a third motor?
03:09 AM pink_vampire: i have very small space, and i want to make something simple just to cut few big parts out of wood
03:10 AM rmu: third motor would restrict you to smaller work envelope but (probably) would massively increase quality and speed of cuts
03:10 AM pink_vampire: after I finish i want to dissemble the machine, i want it as a temporary machine
03:10 AM pink_vampire: for only one job
03:11 AM rmu: it is some kind of "parallel" kinematics.
03:11 AM pink_vampire: I'm thinking to make it without the Z axis
03:12 AM rmu: i would not trust those chains staying on the sprockets and add a guard.
03:12 AM pink_vampire: so I will plunge the Z axis by hand and then run the machine to cut on the x and y
03:14 AM SpeedEvil: pink_vampire: i assume you're aware of the purchasable one with optical tracking of a 'handheld' platform which just requires you to keep +-3cm of the cut to keep the 'fine' alignement motors in scope?
03:15 AM gloops: if its only for one job it might be more efficient to cut the job by hand
03:16 AM gloops: make some templates and push the router round on a guide bush
03:16 AM pink_vampire: SpeedEvil: yes I know about it, I just want a ghetto style cnc that i can make here to cut some shapes out of wood and then reassemble the motor on my milling machine
03:17 AM CaptHindsight: print cutting templates with plotter, route by hand and eye
03:18 AM CaptHindsight: even easier to use a DLP projector to project the outline, trace with marker, then route
03:18 AM gloops: or buy a 1200mm throat fretsaw
03:20 AM pink_vampire: CaptHindsight: it will be pointless because each part is individual and i need several parts
03:21 AM CaptHindsight: https://www.artsupplies.co.uk/item-pantograph.htm
03:22 AM pink_vampire: I dont want to do it by hand
03:25 AM CaptHindsight: https://youtu.be/QC8jnSaCqxY?t=80
03:25 AM SpeedEvil: that would be neat - a 'proper' high spec small high force and stiffness metal CNC, with a pantorouter to blow up the size for wood.
03:25 AM CaptHindsight: machine gun cutting wood
03:26 AM CaptHindsight: very uhmerican
03:28 AM CaptHindsight: wasn't there a poopstarter with a router bot that
03:28 AM CaptHindsight: rolled itself around while routing
03:29 AM CaptHindsight: https://youtu.be/i5h821pEA0Q?t=104
03:29 AM gloops: dont need a pantorouter when youve got a vertical surface (old ally sawbench top) https://www.youtube.com/watch?v=J82ggHEGOt4
03:29 AM CaptHindsight: https://www.goliathcnc.com/
03:29 AM pink_vampire: maybe is a bipod kinematic?
03:30 AM pink_vampire: just upside down?
03:30 AM gloops: i can tenon, dovetail finger joint the end of anything, under 2 foot 6
03:30 AM gloops: which is ok unless you want a bed making in one piece
03:32 AM pink_vampire: CaptHindsight: you miss the point - I want to take the motors from the mill, build something temporary, cut some parts, and be done with it
03:32 AM gloops: i think the maslow people will have worked out the non trivial kins pink_vampire
03:32 AM gloops: for linuxcnc
03:32 AM gloops: it must be somewhere online
03:34 AM gloops: well i better get something done, my mrs wants to see saleable products by the end of this week
03:36 AM CaptHindsight: https://www.youtube.com/watch?v=7hEXwyJ2B78
03:36 AM CaptHindsight: Hexapod Robot CNC Router
03:36 AM pink_vampire: Published on Mar 31, 2008
03:37 AM CaptHindsight: http://www.hexapodrobot.com/forum/viewtopic.php?t=12&f=14
03:37 AM CaptHindsight: modify a roomba
03:37 AM CaptHindsight: routes and cleans up after itself
03:38 AM pink_vampire: https://caelinux.com/CMS3/
03:38 AM CaptHindsight: https://watercolorbot.com/
03:39 AM pink_vampire: CaptHindsight: normal XY based
04:12 AM rmu: airbus phases out A380
04:13 AM rmu: last deliveries in '21
04:15 AM pink_vampire: https://www.youtube.com/watch?v=oAyZxQSMNhg
04:16 AM jthornton: morning
04:17 AM pink_vampire: hi jthornton
04:45 AM jthornton: hi pink_vampire
04:47 AM XXCoder: hey pink_vampire
04:48 AM pink_vampire: hi jthornton & XXCoder
04:48 AM XXCoder: hows things there pink
04:49 AM jthornton: XXCoder: snow gone yet?
04:49 AM pink_vampire: i want to make a disposable cnc machine
04:49 AM XXCoder: not yet slowly going away. had to drive carefully tho. black ice aloy
04:49 AM XXCoder: disposble cnc machine? as in use and throw away?
04:50 AM pink_vampire: correct
04:50 AM XXCoder: looks like tomorrow will vbe 38f and light rain allll day
04:50 AM pink_vampire: something for only one job
04:50 AM XXCoder: like ghost gunner lol
04:50 AM pink_vampire: like that https://www.youtube.com/watch?v=oAyZxQSMNhg
04:51 AM SpeedEvil: pink_vampire: I may have missed it - but what sort of accuracy are you hoping for?
04:51 AM XXCoder: interesting'
04:51 AM pink_vampire: +-1mm
04:52 AM SpeedEvil: ah - quite tight then
04:52 AM XXCoder: yeah large surface thats pretty tight tol
04:52 AM XXCoder: i would use more stronger method to move,. like steel ropes
04:52 AM pink_vampire: it is more art and curved cuts
05:12 AM * Loetmichel is doing the "danger mouse" again... sawing off 7075 alu with a wood sablade in a selfmade arbor made from an M8 screw... and the workpiece glued to the table with CA glue ;) -> http://www.cyrom.org/palbum/main.php?g2_itemId=17295&g2_imageViewsIndex=1
05:13 AM XXCoder: sliced mouse
05:13 AM Loetmichel: I just hope the 4mm Polycarbonate swarf guards can hold the impact... :-)
05:14 AM pink_vampire: rotate 90 deg and cut with endmill
05:15 AM gloops: just had problems booting cnc computer, took about 6 goes to boot up
05:15 AM gloops: *shock*
05:16 AM XXCoder: wonder whats up with that pc
05:16 AM gloops: ive been switching it off at the mains instead of shutting down, dont know if thats related, i darent shut it down now lol
05:16 AM rmu: Loetmichel: milling a heatsink?
05:17 AM XXCoder: some designs its better to use saw
05:17 AM XXCoder: expecially if its hard to do features that match each other
05:18 AM pink_vampire: XXCoder: it is high speed spindle, on low speed there is almost no torque
05:19 AM Loetmichel: no, need a pice thats only 15mm high on the mill ;)
05:20 AM Loetmichel: and faceing that off takes ages. its 25
05:25 AM CNC_Brian: Guy's, trying to setup a new controller on VMware so I don't have to stand in a freezing shop.
05:25 AM fdarling: CNC_Brian: you mean run LinuxCNC inside of a VM?
05:25 AM pink_vampire: CNC_Brian: how?
05:25 AM CNC_Brian: Getting an error about trivkens not becoming master in 3 seconds
05:25 AM XXCoder: vm is not realtime
05:25 AM CNC_Brian: That was my question
05:26 AM CNC_Brian: Is it because Im on VM trivkens will not play ball
05:26 AM fdarling: I am trying to do the same thing... I want to test an optoisolator board I created at home on my non-realtime computer, I wanted to know if there was a way of relaxing the realtime restrictions for the purposes of testing basic I/O
05:26 AM CNC_Brian: I do have an rt kernal
05:26 AM XXCoder: even so vm simply cant act as realtime
05:27 AM XXCoder: second inside vm may well be 3 seconds real time
05:27 AM CNC_Brian: I wouldn't try to run a live machine Im just writing the config
05:27 AM XXCoder: theres way to just install linuxcnc on your pc
05:27 AM XXCoder: i have linuxcnc on my pc and its not realtime
05:28 AM CNC_Brian: Think that's what I need to know
05:29 AM XXCoder: i used a workaround to get repo installed and get it to install
05:29 AM XXCoder: but its not a nice workaround dunno if theres better
05:30 AM CNC_Brian: Actually it says something about Note: Using POSIX Realtime after it spits the dummy
05:30 AM XXCoder: have to use sim version if not using realtime
05:30 AM XXCoder: but not sure if you can configure and run real machine
05:30 AM CNC_Brian: Cool will give that a go. Thanks all!!
05:37 AM jthornton: you could install linux and have a dual boot
05:40 AM Tom_L: morning
05:42 AM CNC_Brian: OK that worked to a point
05:43 AM CNC_Brian: I can now get passed where it was failing but steppen is having kittens because we are using a none realtime.
05:47 AM Loetmichel: sensille: btw: that saw taxed the spindle to the max... full 800W draw. the "new" FU can display the drawn current :-)
05:47 AM Loetmichel: took 0,5mm deep cuts at 8krpm
05:47 AM XXCoder: so your vdf is working fine again?
05:47 AM Tom_L: chinaco amps
05:48 AM Loetmichel: XXCoder: took the one of the new machine until the parts arrive to fix the old one
05:48 AM XXCoder: ahh ok
05:48 AM XXCoder: thought you had stockpile of some parts
05:48 AM Loetmichel: i have
05:48 AM Loetmichel: but no 15N120 igbts ;)
05:49 AM Tom_L: got my thread mill macro working last night
05:50 AM XXCoder: awesome :)
05:50 AM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Smartcam/ThreadMill.mcl
05:50 AM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Smartcam/threadmacro1.jpg
05:50 AM Tom_L: probably not useful for anyone else
05:51 AM Tom_L: horizontal lines are maj min D for a couple threads i was testing
05:51 AM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Smartcam/threadmacro3.jpg
06:41 AM gloops: these mitre clamps that arent square are great
08:05 AM Jymmm: skunkworks: lol
08:24 AM sensille: Loetmichel: apropos watts: with 3A the steppers get warm to the touch, but not hot
08:24 AM sensille: let's say <40C
08:28 AM gloops: probably now low current setting for idle with those drivers, i think mine motors are on the max amps, they get quite hot but never any trouble, they sound a lot better with full power
08:28 AM gloops: but the drivers drop to half current when the motor isnt turning
08:32 AM Jymmm: Um, what does this photo have to do with air hose? lol https://images.homedepot-static.com/productImages/20984a31-c4a8-4cf8-9935-2302202f5871/svn/husky-air-hoses-576-50a-hom-77_1000.jpg
08:33 AM gloops: looks like he does a lot of work in there
08:33 AM Jymmm: Not to me, looks WAY TOO CLEAN
08:33 AM gloops: lol, or she
08:44 AM Loetmichel: sensille: steppers can have ~80°C before getting damaged. you still have some "headroom" for more current then ;)
08:45 AM sensille: also i have a box of cpu heat sinks
08:45 AM Loetmichel: gloops: the TB6560 dont autodrop. they have however a "sleep" input
08:59 AM gregcnc: https://bgr.com/2019/02/13/home-depot-bomb-threat-bathroom/
09:02 AM Jymmm: Gawd, ppl need to pull the stick out of their ass
11:23 AM fragalot: 'sup
11:42 AM gloops: evening
12:40 PM Jymmm: I'm going to try to replace more parts now that the rain paused. If I get that done, is there anything I can test before applying power? I only have one spare 50A fuse =(
12:40 PM fragalot: measure resistance, check for shorts, measure isolation if you have an isolation tester, ... ?
12:46 PM SpeedEvil: Jymmm: you can use wire as fuse. If you pick a wire diameter with a 10A fusing say
12:46 PM SpeedEvil: (NOT a 10A rated wire)
12:46 PM fragalot: single strand of fine copper wire from a fexible cable is approximately 5A
12:46 PM Loetmichel: fragalot: 4A
12:47 PM fragalot: (ill advised, but..)
12:47 PM SpeedEvil: Something like that
12:47 PM fragalot: Loetmichel: depends on the wire, but yes :D
12:47 PM Loetmichel: and "super slow blwo"
12:47 PM Loetmichel: blow
12:47 PM SpeedEvil: Will blow pretty fast at 50A
12:47 PM fragalot: lol
12:47 PM Loetmichel: at least if you take a standard 1,5mm^2 stranded wire
12:48 PM CaptHindsight: no lets argue over how many amps an unknown strand of copper wire can carry
12:48 PM CaptHindsight: thats productive
12:48 PM fragalot: CaptHindsight: ok fine. 5A!
12:48 PM fragalot: unless if its cold out
12:49 PM CaptHindsight: how many amps for a hot dog?
12:49 PM fragalot: before or after its cooked?
12:49 PM * Loetmichel has seen plenty of devices with soldered or simply wound around strands like you descripe on 5*20 or 6,35*35 glass tube fueses
12:49 PM fragalot: and was the water salted?
12:49 PM CaptHindsight: yes
12:49 PM fragalot: in that case, about green.
12:50 PM fragalot: Loetmichel: even commercial devices from the usual suspects sometimes have a wire bridge as a fuse.. :/
12:50 PM CaptHindsight: Jymmm: how mnay small jumper cables with alligator clips can you spare?
12:51 PM Loetmichel: fragalot_ you mean like this one where all the filtering is missing? -> http://www.cyrom.org/palbum/main.php?g2_itemId=4891&g2_imageViewsIndex=1
12:51 PM Loetmichel: (at least it has a (soldered in) fuse
12:51 PM fragalot: Loetmichel: like that, but sans the glass fuse
12:51 PM CaptHindsight: Jymmm: do you have access to a dungeon with a rack, asking for a friend
12:52 PM Loetmichel: fragalot: the best thing is the "pfc" thats just a wire jumper
12:52 PM Loetmichel: (behind the two blue varistors)
12:52 PM fragalot: Loetmichel: carefully calibrated jumper
12:53 PM Loetmichel: ... and they sold that as "CE" and "80+ Gold"
12:53 PM Loetmichel: i doubt it ;)
12:53 PM fragalot: as long as nobody complaints & starts up a lawsuit, CE means nothing
12:54 PM Loetmichel: it means "complies to all regulations relevant" and is as you rightfully stated a self-cert
12:54 PM CaptHindsight: Jymmm: you could disconnect the heaters and substitute a low watt light bulb as a load
12:55 PM Loetmichel: but if it hasnt any PFC at >50(?)W its not EU-importable
12:55 PM SpeedEvil: 30, from memory
12:55 PM SpeedEvil: It's been a while though
12:55 PM fragalot: Loetmichel: big difference betweeen isn't and shouldn't.
12:55 PM Loetmichel: somewhere in that range
12:56 PM Loetmichel: fragalot: sure.
12:57 PM fragalot: my kaiser automatic boring head arrived today
12:57 PM * SpeedEvil is pondering ordering 5kW of battery charger PSUs from china that _certainly_ won't qualify
12:57 PM CaptHindsight: the real problem is that it is 45F right now but going back down to 5F tonight
12:57 PM fragalot: import duties were less than i'd expected
01:07 PM gloops: youll have to show us it in action sometime fragalot, it looked a classy bit of gear
01:08 PM fragalot: agreed. I'll try to get it to run tomorrow or sunday
01:08 PM fragalot: it certainly feels smooth
01:08 PM fragalot: and the boring bars just slide in ever so snugly
01:09 PM HighInBC: hot
01:09 PM fragalot: :P
01:14 PM FinboySlick: fragalot: Kaiser boring head for mister fancy-pants eh?
01:16 PM fragalot: FinboySlick: Indeed.
01:18 PM fragalot: FinboySlick: https://i.ebayimg.com/images/g/wy0AAOSwy2pcHgyp/s-l1600.jpg
01:19 PM fragalot: https://i.ebayimg.com/images/g/1IAAAOSwjfdcHgyt/s-l1600.jpg
01:19 PM FinboySlick: All the fancy.
01:19 PM fragalot: if it wasn't for the chewed up screws, i'd have believed the seller if they said it was new old stock
01:20 PM FinboySlick: Wouldn't that look nice on a schaublin...
01:21 PM fragalot: now to figure out a part that needs both a facing head, and a X-axis referenced spiral capable dividing head
01:21 PM CaptHindsight: fragalot: I needed one a few years ago for a ~120mm dia bore but 250mm deep
01:22 PM fragalot: CaptHindsight: sounds expensive
01:24 PM CaptHindsight: ended up honing it for 8 hrs, only had to take .05mm off
01:24 PM fragalot: xD
01:25 PM fragalot: at that point you'd think its worth considering grinding it in on a rotary table
01:25 PM fragalot: with a dremel mounted in your spindle
01:26 PM CaptHindsight: was surprised that the speed shops couldn't just bore cylinder sleeves
01:26 PM CaptHindsight: they have to be in a block
01:27 PM fragalot: probably can't mount them
01:27 PM CaptHindsight: yeah
01:27 PM CaptHindsight: could have made a fixture for them
01:30 PM FinboySlick: Makes me wonder if it would be possible with today's tech to smooth bore an engine piston so well that it would act as an air bearing and require no seals. I guess you'd need ceramic sleeves with pretty predicable expansion properties.
01:30 PM fragalot: problem is differential heat expansion
01:32 PM CaptHindsight: FinboySlick: the honing did that, but my app the stroke speed was mm per hour
01:34 PM FinboySlick: fragalot: You mean between piston and cylinder?
01:34 PM fragalot: FinboySlick: yes
01:35 PM CaptHindsight: https://www.enginelabs.com/news/video-the-benefits-of-a-gapless-top-piston-ring-kit-with-total-seal/
01:35 PM fragalot: plus the hone marks act as an oil trap for lubrication
01:35 PM fragalot: i'm not sure if the "air bearing" technique would work without forcing air in between the walls
01:36 PM CaptHindsight: https://www.techbriefs.com/component/content/article/tb/techbriefs/materials/2258
01:37 PM CaptHindsight: https://patents.google.com/patent/US1524715
01:37 PM CaptHindsight: https://www.carsales.com.au/editorial/details/aussie-invention-eliminates-piston-rings-40773/
01:38 PM gloops: https://www.ebay.co.uk/itm/LATHE-METAL-LARGE-BELT-DRIVEN/323683837781? nema17s or nema23s?
01:39 PM Jymmm: I got one relay almost replaced. It's wired, but just hanging there now, as the rain started, than asfter I pickerd up and closed everything the rain stopped (for the moment)
01:39 PM fragalot: CaptHindsight: so.. the tesla "no moving parts" one-way check valve?
01:39 PM FinboySlick: CaptHindsight: That aussie one reminded me of the Napier Deltic.
01:39 PM CaptHindsight: https://patents.google.com/patent/US4724800
01:40 PM FinboySlick: CaptHindsight: You ever seen it? Triangular opposite piston engine.
01:40 PM FinboySlick: Completely bonkers.
01:40 PM andypugh: Napier deltic?
01:40 PM FinboySlick: yeah, andy would know.
01:40 PM CaptHindsight: not sure, there are some odd designs out there
01:40 PM FinboySlick: Hehe, figure it would perk up the brit ;)
01:41 PM andypugh: I am a bit of a fan of Napier engines.
01:41 PM CaptHindsight: https://www.youtube.com/watch?v=D3bj47TAYiU
01:41 PM CaptHindsight: 3 cranks
01:41 PM andypugh: The Napier Nomad is fun. Diesel aero engine, opposed piston. With an afterburner....
01:42 PM FinboySlick: andypugh: Stollen from the luftwaffe!
01:42 PM CaptHindsight: 3 compressors
01:42 PM andypugh: FinboySlick: Not really, very little in common with the Jumo
01:42 PM FinboySlick: andypugh: Just taunting you.
01:43 PM andypugh: How about the Rootes / Commer TS3?
01:43 PM FinboySlick: (and hoping Loetmichel would bite too)
01:43 PM andypugh: https://www.youtube.com/watch?v=pGaISFg_ZIw
01:44 PM CaptHindsight: https://www.youtube.com/watch?v=bBrUrgNf5y8
01:44 PM andypugh: Somebody made a TS3 with ecentrics for the rocker pivots, to give variable compression ratio.
01:45 PM FinboySlick: Supercharger required for proper intake/exhaust?
01:45 PM andypugh: Yes.
01:45 PM CaptHindsight: http://bbs.homeshopmachinist.net/threads/69657-Piston-Cylinder-lapped-fit-no-rings
01:46 PM andypugh: Pretty sure that model is wrong, I think that the pistons are not in exact antiphase.
01:48 PM Tom_L: CaptHindsight tapered fit?
01:51 PM andypugh: Those TS3 engines sound a bit special… https://www.youtube.com/watch?v=p8k35_153Vw
01:55 PM FinboySlick: Oh wow, those were actually built.
01:56 PM FinboySlick: Makes one wonder how efficient they could be if we'd have put effort as we had in conventional engines into them.
01:59 PM andypugh: Well, uniflow 2-stroke diesels _have_ been further developed, to make the most efficient engines in the world: https://en.wikipedia.org/wiki/Wärtsilä-Sulzer_RTA96-C
02:00 PM sync: yeah, not in an automotive variant tho
02:00 PM andypugh: A 25,000 litre 100,000hp engine might be a bit much in a car :-)
02:01 PM fragalot: its fine
02:16 PM Loetmichel: andypugh: especially considering the size... wouldnt fit the streets ;)
02:18 PM fragalot: Loetmichel: just go vertical & avoid bridges
02:20 PM SpeedEvil: andypugh: 20% better than turbodiesels in cars - neat.
02:29 PM fragalot: CaptHindsight: ever looked at fabrisonic?
02:43 PM FinboySlick: mention the Napier, out comes the brit. Mention Wartzsila, out comes the german.
02:43 PM andypugh: Hmm, how to calibrate a Faro arm? I think I need to find a way to hold the joints at specific angles.
02:43 PM * FinboySlick amused.
02:44 PM andypugh: But Wartsila are Finnish and Sulzer are Swiss?
02:45 PM FinboySlick: Darn... My stereotypes all broken.
02:46 PM FinboySlick: andypugh: My initial thought on the Faro is that if you probe a known-sized object in a few different spots, the computer should figure out the rest.
02:48 PM FinboySlick: eg, this 123 block here is 1"x2"x3" in this spot, and it's also 1"x2"x3" in this spot.
02:48 PM andypugh: In theory this should be possible, agreed. Put the point at a location and wave the joints about to get a lot of simultaneous equations. Then the system should be able to figure out the mapping between voltage and joint angle, and then derive the Denavit-Hartenberg parameters too.
02:48 PM andypugh: In practice that sounds hard.
02:49 PM FinboySlick: nah, they'll use agile to develop a cloud-based neural network of ai running node.js and it'll all be magic.
02:50 PM andypugh: Yes, well, in the interim….
02:50 PM FinboySlick: You're the one stuck with the problem, right?
02:50 PM andypugh: Yes.
02:51 PM andypugh: I think I need a Faro arm to measure my Faro arm joint lengths etc :-)
02:51 PM jthornton: lol
02:52 PM * jthornton finally sorted out why the coop software would not run as a service with systemd :)
02:52 PM FinboySlick: Does it have limits on all joints?
02:52 PM andypugh: The joints are ptentiomters.
02:52 PM FinboySlick: I mean, none of them can do more than 360 degrees?
02:52 PM andypugh: So it’s absolute, but difficult to work out the references.
02:53 PM andypugh: Indeed, all move about 270 degrees
02:53 PM FinboySlick: How linear is the potentiometer?
02:54 PM andypugh: I have no way to tell. See my first question.
02:55 PM fragalot: break out the box of string & pythagoras that thing
02:55 PM FinboySlick: The only sane reference positions are the rotation axis.
03:01 PM andypugh: Now there’s a thought....
03:02 PM andypugh: I have a bunch of servos. I can use a servo motor + encoder as an angle transducer
03:03 PM andypugh: Then I just need a straight-edge to get one zero-degree reference angle.
03:34 PM togo: what is the best stepper driver hardware supported by LinuxCNC these days?
03:37 PM jthornton: Mesa 7i96, 7i76E, 5i25/7i76, 6i25/7i76, 7i92/7i76
03:39 PM togo: Are those open source?
03:41 PM togo: or closed loop / trinamic?
03:47 PM jthornton: not sure I understand the question but they are open loop stepper driver cards that work with LinuxCNC
03:52 PM andypugh: togo: Or do you mean the actual stepper power stage?
03:54 PM togo: well I would need the complete path between the controlling computer and the steppers
03:54 PM andypugh: And which parts do you currently have?
03:55 PM andypugh: “Best driver” depends on the size of the steppers, to an extent.
03:55 PM togo: I say open source mainly because of economy and availability of circuit diagrams to repair things if something goes wrong...
03:55 PM andypugh: But if you don’t alreadyhave the steppers then the Leadshine closed-loop sets look like a good idea
03:55 PM togo: True thaose are nema 23 steppers 3A max
03:57 PM togo: but I would be willing to not top out the current if for example trinamic drivers could 'close the loop' for me
03:57 PM andypugh: 3A you might as well just buy generic TB6600 from eBay and accept that they are cheap enough not to bother repairing.
03:57 PM andypugh: https://www.ebay.co.uk/itm/TB6600-Stepper-Motor-Driver-Controller-Single-Axis-4A-9-42VDC-Micro-Step-CNC/283114044871?hash=item41eae97dc7:rk:4:pf:0&var&checksum=2831140448710f75e2f249154555aa65132633ef76f3&enc=AQADAAAC8FjVrDbVsZ8oH%2F8PNHtt9VX4%2Fw7FZcmMuqsX8uaFEduVIs9lounDpzatgernVZ7LDL%2Fjbr0BHDtPlN2f%2F5gqZRgNsTLdDZ6Ih6%2BvZz%2FBNIxNQYaS4VkmHJJE%2FS6kBPthHpjHZHdO7ZmHaj8BwyBXWjCozG2NxnWDfEg%2B6kjmwyg%2FGWe4W2yzWsH%
03:57 PM andypugh: EXVd9WsRKXgD%2FNB%2FB7rB2OaYhJYS02coXkWV%2FswTZMYBnpdpOm4RQDUx%2FbUeQBXK%2BiK8P5o9KeLwFclis6CKgpkfFNGR78ZLo6VMX4z6eoMDOwdXh9W5wEAteOZlFxgvjt01RV00%2B9vBf4JFT4zKeZ4B%2FXYu1iy%2FQZKpRjllKB7ypU9hQnsePSyD2ommqHys%2BXo29cKKmP8PjWnSgKuGuJLZ0AOlEhxX5sAjlArxLoWdez1w6o8moBMqyZXdW4RI5Mdscu9C2YbsgfftA9H6CYbmf1YPOvqFWxyyAhL1%2FCqX7ulTDQhtVdrH0Uq79CtL4OgONWN4lngpS0kvQE0z2DPFEKL5Lo5Rfweipmg8JZNgq8eMM6%2BSnPXWYg0uPbd80CT5zhFMPux%2
03:57 PM andypugh: YH8D62%2BNhSHoBr2fU7jYz%2FSMQ9%2B22qqPD9eXgFwQ6mRjoIx%2BVkZzdtE8ko%2BC%2BLAikvdpD4ND1jKweVvzl%2FbQh%2B8iiuhmAQ9%2BrycEKtwoQ7kRqe3etmYtfRtTXmiq5RLZX1XlWLsDvqc3l2SsnRsQpFmxal69%2Ffxl0oYe%2BmCzkYLklNU0UCgNbYeHTQ25U5YQ7xd90YwQKerMLQqrZwwqUYmdlviyagbOQG7KRHEUpF9hZOud3McdmYtjsdJ%2BxnM%2BGSi0Dij31GLwApvhxcjagFDYmpGT6DyxfobuCpC6oz%2B%2FSemM186wtBzdNa2jfQAkxDSCqRrVFIOxrekD5oxROfNzOzFA5uES%2BTsWzNXRCWK0FAFXpYBpKog5hnitl%2B804
03:57 PM andypugh: VfaRhAxKcVYyX%2BjoZp%2BMlZnv4NNd
03:57 PM andypugh: Eeek!
03:57 PM XXCoder: LINK BOMB!
03:58 PM andypugh: I meant: https://www.ebay.co.uk/itm/283114044871
03:58 PM andypugh: (And, err, how is that even _possible_? )
03:58 PM XXCoder: andy still shorter than one time I acciently pasted entire wiki page in irc channel. I had to close client since it was still spamming
03:59 PM andypugh: £5.99 including postage? I can’t post a postage stamp to China for that.
03:59 PM XXCoder: TO china is the key. out of key they have special treaty for cheap shipping.
03:59 PM XXCoder: *out of china
03:59 PM togo: Amazing that is quite affordable!
04:00 PM XXCoder: tb6600 is pretty good, in least far better than tb6560s I had
04:00 PM andypugh: togo: Search for TB6600. There are some for a very little more that look a bit better.
04:01 PM togo: ok, I#ll check it out, and what goes in between the computer and those?
04:02 PM XXCoder: BOB is your uncle
04:02 PM XXCoder: breakout board :)
04:03 PM gloops: you can get 3 tb6600s for about £20 on ebay
04:03 PM XXCoder: look for cnc breakout board usually pretty cheap also
04:03 PM XXCoder: so basically pc -> BOB -> tb6600s -> machine
04:04 PM andypugh: togo: Depending on how many axes you need and whether your PC has a parallel port you could either use a parallel port or something better. Or maybe something worse, but that’s a small category :-)
04:05 PM togo: exactly I remember last time I investigated LinuxCNC prefered parallel port...
04:06 PM gloops: https://www.ebay.co.uk/itm/Cnc-5-Axis-Interface-Breakout-Board-For-Stepper-Motor-Driver-Cnc-Mill-Mach3-MB/142907628409? thats the standard issue bob with relay and pwm, pretty yesteryear stuff now but they work
04:06 PM andypugh: Nooooo! LinuxCNC _hates_ the parallel port and uses it under duress!
04:07 PM togo: but it hates USB even more, right?
04:07 PM andypugh: Well, yes.
04:08 PM togo: So people use pci cards?
04:08 PM andypugh: But PCI and Ethernet are both well supported. And even ISA
04:08 PM togo: Ethernet is good?
04:08 PM togo: I like that because even old laptops have that...
04:10 PM andypugh: Yes, though it is not as cheap as parport: http://store.mesanet.com/index.php?route=product/product&path=83_85&product_id=290
04:11 PM andypugh: And you need to use this LinuxCNC ISO image to use ethernet: http://www.linuxcnc.org/testing-stretch-rtpreempt/
04:12 PM togo: what is the minimum system requirement ?
04:13 PM togo: MB RAM for example
04:15 PM andypugh: 1GB
04:16 PM andypugh: I run my machines from an 8GB SATA DOM for the HD and 2GB of RAM. But more doesn’t hurt, especially if you might be doing CAD / CAM on the same machine.
04:18 PM togo: Thanks I think I would not, just transfer gcode and cut
04:18 PM togo: And none of you use any trinamic drivers?
04:19 PM togo: Of cource they might be more expensive, and I have no idea if they have anything above 1.x Amps
04:20 PM togo: but relatively silent and possible 'closed loop' could be convincing
04:21 PM gloops: what machine are you building togo?
04:22 PM togo: I am going to convert an aluminum door frame
04:22 PM gloops: this sounds interesting
04:22 PM togo: So far I have those Nema 23 steppers and a 400W air cooled spindle, and also a 5W laser
04:23 PM andypugh: My advice would be to spend as little as possible on your first build and make your mistakes cheaply.
04:24 PM togo: Initially I may have to 3d print most parts
04:24 PM togo: good point!
04:24 PM andypugh: You might well find that an aluminium door frame is a terrible basis for a CNC :-)
04:24 PM gloops: yeah probably parport bob/drivers setup would work fine for that type of machine
04:24 PM togo: I could even just use a smoothyboard and no linuxcnc - what would I be missing out on?
04:25 PM andypugh: I started that way. Then on my latest build I spent more on Mesa cards than on the first machine, including buying the lathe/mill brand new!
04:25 PM togo: andypugh: whay would you say that?
04:26 PM andypugh: If you use a Smoothieboard you miss out on LinuxCNC. Surely that is enough to dissuade you?
04:26 PM togo: The door frame has avery good formfactor and stability
04:26 PM gloops: with 400w spindle and 5w laser you arent looking to push any speed barriers
04:26 PM Deejay: gn8
04:27 PM andypugh: Now, does this look like a bargain? https://www.ebay.co.uk/itm/Cake-Pans-HHIP-4901-2705-10-X-6-X-1-Precision-Granite-Square/392238914229
04:27 PM togo: I wonder why you never went to submit those Open source firmware controllers to LinuxCNC _slavery_
04:27 PM andypugh: Or should I be put off by the “cake pans” description?
04:28 PM gloops: after trying to clamp up some frames with chinese mitre clamps today, yes it looks an absolute bargain andypugh
04:28 PM andypugh: togo: Because things like Smoothieboard do _exactly_ the same job as LinuxCNC. LinuxCNC + Smoothieboard / GRBL is a pointlessly redundant system
04:29 PM gloops: Squareness is .0001"
04:29 PM andypugh: gloops: Sarcasm?
04:29 PM gloops: andypugh no it looks square - my clamps arent lol
04:30 PM andypugh: Mach3 + Smoothstepper is a pointlessly redundant system too, but Mach3 make money by supporting the configuration, so it is supported.
04:30 PM togo: ok, true, so LinuxCNC does nothing more than the Arduino/Arm/Ramps etc
04:31 PM andypugh: No, though it might well do it better, and definitely more flexibly.
04:31 PM togo: I figure squareness would be adjustable?
04:32 PM andypugh: Or fixable in software
04:33 PM andypugh: (There is a config somewhere for LinuxCNC and an out-of-square machine)
04:33 PM andypugh: <closes eBay having bought 4 123 blocks, 2 waterproof calipers and a granite square>
04:43 PM rmu: wtf are waterproof calipers???
04:43 PM andypugh: Digital calipers that continue to work when you splash coolant on them
04:43 PM rmu: aaah ok digital
04:44 PM andypugh: Yes, I am not American so have never seen a dial caliper :-)
04:45 PM Tom_L: my first pair was dial
04:45 PM Tom_L: i gave them to a friend after i got a digital pair
04:45 PM rmu: me neither. i am used to vernier calipers.
04:45 PM andypugh: You can do a lot more with digital.
04:47 PM rmu: the chinesium digital are a waste of money time and brain
04:47 PM andypugh: As an example, to make a 20mm part on an Imperial lathe. Set the caliper to 20mm. Zero it, switch to imperial. Now when you measure the work it tells you directly how many thou to take off.
04:47 PM Tom_L: https://www.amazon.com/Mitutoyo-Digimatic-Micrometer/dp/B00WMLRBSO
04:47 PM Tom_L: i was given one of those and like it alot
04:48 PM Tom_L: still in the shrink wrapper
04:48 PM andypugh: Yes, I have those in 0-25 and 25-50
04:49 PM Tom_L: i've got an older pair 0-1 and 1-2
04:49 PM Tom_L: non digital
04:50 PM Tom_L: what projects are you up to lately?
04:51 PM andypugh: I was skiing last week, and next week, so this week I haven’t been able to settle. So mainly TV and fiddling with small LinuxCNC bugs.
04:52 PM andypugh: Still have the Holbrook Lathe fixed steadies to finish.
04:53 PM Tom_L: you must be on a first name basis at the foundry
04:54 PM andypugh: err, yes.
05:34 PM Jymmm: AND WE HAVE HEAT!!!!!!
05:34 PM Jymmm: Thank you all very much for your help!!!!!!
05:35 PM Tom_L: yay
05:36 PM Jymmm: When the PTC blew, it actually arced thru the other side of the sheet metal and made a relay toasty as well, replaced it just because I coould
06:08 PM jthornton: yippie
06:11 PM Jymmm: jthornton: thank you =)
06:15 PM jthornton: yw
06:15 PM jthornton: that looks so much like vw lol
06:16 PM * jthornton wanders up to the living room
06:16 PM Jymmm: haha
06:38 PM gloops: how many HDs are there on here?
07:28 PM Tom_L: HDs?
07:30 PM gloops: seems to be the designated ID some computers give out
07:59 PM Connor: Anyone know anything about adding coolant to a surface grinder? Oh.. and it has a electromagnetic chuck...
09:03 PM CaptHindsight: not unless you are wet grinding
09:33 PM Elmo40: Connor, no problem
09:33 PM Elmo40: it is very beneficial for coolant in grinding
09:33 PM Elmo40: the material burns if you dont (depending on cut dept, of course)
09:34 PM Elmo40: plus, helps wash away the material from the stone.
09:38 PM Connor: Yea. It's a older unit.. doesn't look like it ever had coolant.. and I wasn't sure if would be issues with the chuck since it's powered.
09:40 PM Connor: http://www.ivdc.com/cnc/0907180903.jpg
09:40 PM Elmo40: with that one you will get a spray everywhere...
09:41 PM Wolf__: might want to make a wheel guard
09:41 PM Connor: I'll have to make a enclosure.. He has the wheel guard too.. just not mounted.
09:41 PM Wolf__: fun part is figuring out the drain off the table
09:44 PM Connor: How are they normally done? and is equipping one that's not coolant ready a silly idea?
09:44 PM Connor: I don't know much about surface grinders..
09:45 PM Wolf__: mine has a slot/hole with a flange, haven’t figured out how I
09:45 PM Wolf__: I’m going to do the coolant recovery yet
09:50 PM Connor: It has some pretty bad backlash on the Y axis. Around .131" or so.
09:50 PM Connor: Not sure how big a deal that is.
09:50 PM Jymmm: Wolf__: HAVE HEAT =) Thank you for the help
09:51 PM Wolf__: heat is good
09:51 PM Wolf__: y axis backlash shouldn’t be a issue on a surface grinder
09:53 PM Connor: Damn. You can add DRO's to them too.
09:54 PM Wolf__: yup, for z height and Y step over and doing stuff up to a shoulder
09:54 PM Wolf__: cnc isnt a bad idea either lol
09:55 PM Connor: I would hate to try to dial in the Z.. co-sine error... :)
09:55 PM Connor: getting the scale perfect would be way hard.. not as critical on a mill.
09:56 PM Wolf__: not really, just run z up and down till the DTI says 0 runout with the axis
09:59 PM Connor: Dang it.. the ones I use on my mill is only good for Resolution: 0.0002", repeatability: 0.0002"
10:00 PM Wolf__: 5 um
10:04 PM Connor: Looks like you can get 1um glass scales else where..
10:04 PM Wolf__: I have some of those as well on my lathe
10:05 PM Connor: I have to say though.. I swear the mill can do .0001"
10:05 PM Connor: But maybe that's just the readout and it can be off a bit.
10:08 PM Wolf__: most things you can probably get to move .0001” by holding it lol
10:11 PM Wolf__: only reason I put 1um on my lathe is for the cross slide
10:11 PM Wolf__: 5um on my mill because in reality even that much resolution is a waste