#linuxcnc Logs

Jan 29 2019

#linuxcnc Calendar

01:58 AM Loetmichel: mornin'. Somehow my google-fu is low today. Anyone an idea how to urge a Hp laserjet M452dn to do a calibration run? it has a few mm of colour shift.
02:10 AM Loetmichel: sensille: indeed
02:15 AM Deejay: moin
04:12 AM jthornton: morning
04:18 AM XXCoder: morning
05:28 AM * Loetmichel just went to the car, searching for a few Thumbdrives that have fallen out of my pocket. cleaned out the back seat and trunk while i was at it. Result: three notebooks standing here charging back up... one Lenovo E520, one Japanese manufacturer "Gallery B-212", one Lenovo E6510 :-) ... somtimes i am a wee bit messy ;)
05:32 AM sensille: they've probably been there for a reason ...
05:34 AM XXCoder: lol
05:34 AM Loetmichel: sensille: reason is that i am a bit forgetful
05:35 AM Loetmichel: every time i do a journey where i need a notebook on the destination i pack one into the car... and then forget to get it back out when i am back home :-)
05:35 AM XXCoder: man how many notebooks do you have? lol
05:37 AM Loetmichel: 12
05:37 AM Loetmichel: working ones
05:38 AM XXCoder: wow. i guess it comes from having tech job
05:41 AM sensille: anything newer than core2?
05:41 AM Loetmichel: indeed
05:41 AM Loetmichel: sensille: only one with a P3, two with Core2, rest I* of several generations
05:41 AM sensille: not bad
05:42 AM Loetmichel: the three i have "found have I7-920, I7-2640(26**) and an I5 with 2.8ghz, forgot which series
05:43 AM Loetmichel: so not THAT old :-)
05:44 AM Loetmichel: and all my notebooks apart from the P3 have 4gb at least
05:49 AM Tom_L: 19°F, Hi 43
05:50 AM Tom_L: Lo 12
05:52 AM sensille: Loetmichel: mutliple notebooks just means you have to search all of them if you're missing a file
09:11 AM russian_troll: JT-Shop: The #linuxcnc index http://www.isaeff.net/logs/%23linuxcnc/index.html
09:13 AM * flyback is watching
09:13 AM flyback: DIRTY CANUCKS
09:13 AM flyback: DIRTY CANUCKS
09:13 AM flyback: man those plasma cutters are awesome
09:22 AM JT-Shop: hmm mesaflash stopped working
09:30 AM jthornton: glad the one in my 7i96 configuration tool works
10:39 AM Deejay: back with ipv6 now
10:54 AM Jymmm: Amazon returns buy the pallet... https://www.youtube.com/watch?v=o5_xEut2p6I
11:27 AM fragalot: gloops: https://imgur.com/gallery/q2qiYuF
11:29 AM rmu: hehe
11:30 AM gloops: yes a series of votes later today could determine the outcome of Brexit
11:30 AM rmu: somebody invent the egg-unbeater
11:30 AM fragalot: oh yeah I forgot that was today
11:30 AM gloops: ammendments to stop no deal etc, it may well also determine whether civil order is maintained here
11:31 AM fragalot: is there an outdoor webcam outside parliament? :P
11:32 AM gloops: probably lol, i think it may take a few days for the reality to sink in, to those leavers who have been promised for 2 years that we leave on march 29, tommorrow they might well be waking up to the reality that we are not leaving
11:32 AM fragalot: I'm just hoping for a delay for personal reasons :P
11:33 AM fragalot: June would be good.
11:33 AM gloops: probably going to be some kind of delay i think
11:33 AM rmu: a delay till june can't really hurt
11:34 AM fragalot: gives seabourne freight some time to work out a lease for a boat
11:34 AM rmu: a longer delay would open the question what to do with elections in may
11:34 AM gloops: oh i dont know, a lot of people will be very suspicious of any delay
11:34 AM gloops: people in the UK anyway
11:35 AM Loetmichel: fragalot: thats surprisingly accurate
11:35 AM gloops: the remaniacs plan is obviously - vote down any deal, time and again, lobby for en extension, vote down any deal again, extension etc
11:36 AM gloops: eventually another referendum - remain
11:36 AM rmu: yeah, that is obvious
11:37 AM rmu: but what is the plan of the leavers
11:37 AM fragalot: to leave at any cost
11:37 AM rmu: don't think so
11:37 AM gloops: the ERG group were pretty certain there was no way round article 50s final date - march 29th, so they vote down any deal and let the clock run out
11:38 AM rmu: but it seems everybody has a different the red line
11:38 AM fragalot: rmu: the real question is: which leavers?
11:38 AM fragalot: the "leave" vote could have had any number of different reasonings behind it, depending on which public figure they listened to
11:39 AM gloops: ERG is about 80 MPs, DUP is 12, if those groups could back May shes only about 30 votes short - if
11:39 AM rmu: ERG?
11:39 AM rmu: euro remainer group?
11:39 AM gloops: european research group - the hard brexit tory MPs
11:40 AM fragalot: comical
11:40 AM rmu: i got the impression DUP is opposed to hard brexit because that would virtually guarantee "troubles"
11:40 AM gloops: it is known as Carry on Brexit lol
11:41 AM rmu: but what do i know
11:41 AM fragalot: https://www.youtube.com/watch?v=kNe8qK_-wUI <== she's summing it up quite well
11:41 AM gloops: the DUP will take no deal/hard brexit, they see no problem at all with WTO so far as the border goes
11:42 AM fragalot: have they actually looked at the WTO rates?
11:42 AM gloops: (what they might be hoping for is the EU/Ireland to put troops on their side)
11:42 AM fragalot: not to mention the overhead that comes with it
11:42 AM gloops: the standard WTO rates are a bit steep but they will only apply where no trade agreement is made
11:43 AM fragalot: yeah, but trade agreements take years
11:43 AM gloops: sometimes, interim arrangements can be made for essentials or big stuff Trump says he wants a US-UK deal by 2020
11:44 AM Loetmichel: gloops: another referendum with remain will not work
11:44 AM gloops: Loetmichel no i dont think it would solve anything
11:44 AM Loetmichel: EU will not take them back
11:44 AM fragalot: another referendum, sadly, is just not a viable option
11:44 AM gloops: at best the polls are only showing a narrow win for remain anyway, the division will be same
11:45 AM rmu: no, the brexit will and has to happen one way or another
11:46 AM rmu: opportunity for another referendum will be in 25 years
11:46 AM rmu: +-
11:46 AM rmu: the question is
11:47 AM rmu: will the time until some definitive deal is made be more or less chaotic
11:47 AM Loetmichel: rmu: that is out of the question anyway. the question is only "will it be hard and sudden or bearable for the brits with some new deals with the EU
11:48 AM gloops: difficult to speculate, May is in an impossible situation
11:48 AM fragalot: she really is
11:48 AM fragalot: kudos for sticking with it though, i'd have given up ages ago :D
11:48 AM gloops: she has shown some guts not many would deny her that
11:53 AM Loetmichel: indeed
11:53 AM Loetmichel: guts she has
12:07 PM Deejay: re
12:08 PM Deejay: using ipv6 and ssl now :)
12:09 PM Tom_L: expecting an attack?
12:09 PM Deejay: just going with time ;)
12:09 PM fragalot: Deejay is just wary of people listening in
12:10 PM * Deejay feels being stalked by everyone ;)
12:10 PM Deejay: and just because i am paranoid, it does not mean that they aren't after me!
12:11 PM Tom_L: that's just it... they are!
12:11 PM * Deejay fears
12:36 PM fragalot: I wonder if I could make a belt oil skimmer with one of those BBQ spitroast turners :D
12:37 PM fragalot: i've found some cheap US ones, but I can't find one in the EU for under €350 inc. VAT
12:38 PM gloops: belt oil skimmer?
12:38 PM fragalot: https://www.hogetex.be/band-olie-skimmer
12:39 PM gloops: what does it do?
12:39 PM fragalot: continuously scoops out the foreign oils from my coolant sump
12:40 PM gloops: ahh
12:44 PM rmu: fragalot: use automotive wiper motor
12:45 PM fragalot: I think i've got a few industrial 24V geared DC motors lying around
12:45 PM rmu: something like that https://www.pollin.de/p/gleichstrom-getriebemotor-gmpd-404980-1-12-v-310477
12:46 PM fragalot: they look pretty easy to build tbh, all the designs i've found so far just use a weight at the bottom & a pulley at the motor with a wiper on it
12:46 PM * fragalot adds this to the list of things to make
01:03 PM fragalot: this is kinda annoying
01:03 PM fragalot: what is "amendment A"? :P
01:05 PM gloops: oh some garbled nonsense Corbyn came up with
01:05 PM gregcnc: the pump I was looking for was for skimming oil
01:05 PM gloops: erg and dup have pledged support for the brady ammendment
01:06 PM fragalot: found it on the website
01:07 PM fragalot: yeah that one's going to fail
01:08 PM fragalot: 5 - 10cm of snow predicted tonight
01:08 PM fragalot: "or possibly more" ._.
01:08 PM fragalot: gregcnc: why do you need a pump to skim it? or is it to get it moving about?
01:09 PM gregcnc: -32°C tonight and tomorrow
01:09 PM gloops: mainly down to Brady and Coopers ammendments
01:09 PM gloops: Bradys will go through by the look of it
01:09 PM fragalot: gregcnc: normally if we get 20cm of snow, it's like this https://pbs.twimg.com/media/A83MzyiCQAA3Hf-.jpg
01:09 PM gloops: saw that on TV gregcnc, possibly -50?
01:09 PM fragalot: gloops: what does brady entail?
01:09 PM gregcnc: windchills
01:10 PM gloops: bradys calls for re-opening of negotiations on the irish backstop with the EU
01:10 PM gregcnc: not going to be -50°C near Chicago, Minnesota maybe
01:11 PM gloops: -30 is like an hour or 2 outside, your lungs are damaged
01:11 PM fragalot: gloops: you mean remove the bits that the UK itself proposed from the agreement? :D
01:11 PM gloops: if youre sleeping on the streets, youre dead
01:12 PM gloops: fragalot may was stupid to accept the backstop, she was under extreme pressure for time and the EU ruled out any other options, she should have made her stand then
01:13 PM fragalot: gloops: according to the EU's lead negotiator, most of the backstop issues are proposals fomr the UK itself
01:13 PM fragalot: it's not about "accepting" it, it's about having proposed it in the first place
01:13 PM gloops: i knew someone who worked in industrial freezers -28C, i think they could only do 1.5 hour sessions in the freezer before having an hour out
01:14 PM gregcnc: https://www.youtube.com/watch?v=IE3pQfCOxdI
01:14 PM gregcnc: these usually use a floating skimmer
01:14 PM gloops: fragalot i cant remember now, i do remember the UK proposed various technological solutions which the EU rejected
01:15 PM fragalot: because they are not possible
01:15 PM fragalot: as explained by the negotiator in the video I linked earlier
01:15 PM gloops: they are possible but did not exist at the time - UK said they would be ready by march 29
01:15 PM fragalot: what if they aren't?
01:16 PM fragalot: gregcnc: fancy setup
01:16 PM gloops: corbyn loses
01:16 PM gregcnc: those are ~500USD. I'm making something
01:16 PM gloops: fragalot this borderless setup requires some trust and goodwill from either side
01:16 PM fragalot: gregcnc: simple belt skimmers are more than that here
01:17 PM fragalot: gloops: trust means nothing if it can't be put down on paper
01:18 PM gloops: but this is the irish, they will argue forever, never ever concede anything, never compromise, its a special case
01:18 PM fragalot: I doubt amendment O will pass too
01:19 PM gloops: this one could be close
01:20 PM fragalot: I think the "no deal must be ruled out" makes it difficult to vote for for many
01:21 PM phaxx: gloops: we don't need to concede anything - brexit is your idea. :)
01:22 PM phaxx: 'we' being the entire EU, not just the Irish.
01:22 PM gloops: phaxx the irish are going to be stuffed by the EU the minute the UK is out
01:23 PM gloops: however, the door is always open to joining the UK
01:23 PM fragalot: lol
01:23 PM phaxx: I doubt that'd be appealing to many, given the history.
01:23 PM phaxx: NI and Scotland breaking away from the UK are both much more likely, I'd say.
01:24 PM gloops: your 12% corporate tax will gone within 12 months
01:24 PM gloops: unless you join us
01:24 PM phaxx: that's been at risk for a long time as it is, it's not terribly relevant to brexit.
01:25 PM gloops: yes, you can keep it, we'll see to that
01:30 PM gloops: oh that was the scottish ammendment, got them mixed up
01:45 PM gloops: voting on Cooper ammendment, this is the biggie
01:45 PM fragalot: amendment q is an ambitious one, lol
01:46 PM fragalot: gloops: I thought they were on amendment p right now? or did I hear wrong
01:46 PM gloops: i might be wrong lol, i thought this was Coopers
01:47 PM fragalot: oh it IS b
01:47 PM gloops: this could be close
01:48 PM fragalot: after reading it, i'm not entirely sure what they are after
01:48 PM fragalot: other than stating "guys. seriously."
01:49 PM gloops: this one is up to 9 months delay, shocking really but the opposition is behind it
01:49 PM fragalot: I see no mention of any delays in it
01:51 PM gloops: this would guarantee parliamentary time for a private members’ bill drafted by Cooper that would extend article 50 to the end of 2019 if Theresa May failed to secure a deal by late February.
01:51 PM fragalot: I see
01:56 PM fragalot: I'm all for i and j as alternatives.
01:56 PM fragalot: :P
01:56 PM gloops: I might pass
01:58 PM gloops: Cooper fails
01:59 PM fragalot: this has no chance does it? :P
01:59 PM gloops: not going by the results so far
02:00 PM fragalot: thing is.. regardless of any of these amendments, it still has to be agreed with all EU member states too
02:01 PM gloops: yes, have to get a bit closer to the deadline i think, before anyone blinks
02:06 PM gloops: i think the erg are demonstrating their power - they brought mays deal crashing down, but the moment ammendments to delay are tabled, they back her, and when they back her, she wins
02:13 PM fragalot: closer than i'd have thought
02:15 PM gloops: if this one fails, no deal is a real possibility
02:28 PM fragalot: close one
02:28 PM gloops: advisory only though
02:29 PM fragalot: obviously
02:30 PM gloops: EU will take note though
02:33 PM gloops: although their deal lost 200 odd votes, no deal just lost by 8 votes lol
02:33 PM fragalot: yeah, but those 200 votes could be for wildly varying reasons
02:38 PM gloops: https://www.xe.com/currencycharts/?from=GBP&to=USD&view=1D
02:43 PM fragalot: which vote was this?
02:45 PM gloops: brady
02:45 PM gloops: backstop to be replaced
02:45 PM fragalot: Should be fun.
03:14 PM CaptHindsight: gregcnc: https://www.accuweather.com/en/aq/amundsen-scott-south-pole-station/2258520/daily-weather-forecast/2258520
03:15 PM Deejay: are you on vacation? ;)
03:15 PM JT-Shop: I think I just ruined all my parts by drilling the hole in the wrong place
03:15 PM fragalot: JT-Shop: oh no :(
03:16 PM gregcnc: Bahh, I told my wife it's summer in antarctica
03:16 PM JT-Shop: nope optical delusion on my part
03:18 PM MarcelineVQ: happy kind of error
03:19 PM CaptHindsight: ever make a mistake ona part but the mistake made it better?
03:19 PM fragalot: Daily. :D
03:22 PM Joe_Hildreth: I have a questions about stepper driver timing. I have drivers without timing information. I have an oscilloscope. Is there a method or procedure that I can use to determine what the timing specifications might be?
03:23 PM JT-Shop: CaptHindsight: never, they always come out bad when I make a mistake
03:25 PM CaptHindsight: Joe_Hildreth: start with them long, maybe 10mS each and then shorten them until they stop working...
03:25 PM CaptHindsight: then make them slightly longer so they are stable over time and temp
03:25 PM Joe_Hildreth: What do you mean stop working, like missing steps?
03:26 PM CaptHindsight: stop responding to Step/Dir
03:26 PM CaptHindsight: which stepper driver is this?
03:27 PM CaptHindsight: http://wiki.linuxcnc.org/cgi-bin/wiki.pl?Stepper_Drive_Timing
03:27 PM rmu: i would just configure "conservative" settings and test the hell out of it
03:27 PM JT-Shop: Joe_Hildreth: http://linuxcnc.org/docs/2.7/html/config/stepper-diagnostics.html#_testing
03:27 PM CaptHindsight: some of the cheapest boards are in the 150uS range for pulse widths
03:28 PM Joe_Hildreth: I would have to look. At work right now. It is a chinese driver, with limited information. It is opto coupled which I know would increase the timing parameters. The reason I ask is I am still working on tutorials, and I was wondering if you could actually test and benchmark a driver to see what the timing requirements would be.
03:28 PM Joe_Hildreth: Thank you JT-Shop for the link.
03:29 PM CaptHindsight: look for a part number on the driver chips and optos, those are aslo clues
03:29 PM CaptHindsight: aslo=also
03:30 PM FinboySlick: Any of you messed with that controller that turns RC motors into AC servos? I was wondering how well it would do with cordless drill brushless motors.
03:30 PM CaptHindsight: though aslo sounds like as slow
03:31 PM CaptHindsight: whats an RC motor?
03:31 PM rmu: remote controlled model car
03:31 PM FinboySlick: Brushless motors they normally use in drones and RC cars.
03:31 PM Connor: You talking about the Brushless motors?
03:31 PM CaptHindsight: ah brushless DC
03:31 PM gloops: they were making spindles from RC motors in diycnc, well the person is in here as well
03:32 PM Connor: ODrive ?
03:32 PM CaptHindsight: gloops how many HP are they?
03:32 PM gloops: you can get half a dozen nema17s for ÂŁ20 though
03:33 PM gloops: CaptHindsight none, i think they were for pcb milling, but they got them going quite fast, 50k i think
03:33 PM CaptHindsight: of fractional HP spindles, cheese cutters
03:33 PM fragalot: CaptHindsight: you can get 12HP RC brushless motors
03:33 PM FinboySlick: Connor: Yeah, Odrive.
03:33 PM CaptHindsight: fragalot: no kidding
03:34 PM CaptHindsight: you can also get 50 HP non crap spindle motors
03:34 PM rmu: but they won't work as a spindle for very long at that power output
03:34 PM fragalot: CaptHindsight: indeed. :D
03:34 PM fragalot: rmu: not without spending at least half of that on cooling, no
03:34 PM CaptHindsight: so the ODrive is for toy routers?
03:34 PM JT-Shop: Joe_Hildreth: also you can use the calibration tool to test different settings
03:35 PM Connor: https://www.youtube.com/watch?v=87bhEOp3Y3I
03:35 PM gloops: they use those wheelchair motors too
03:35 PM rmu: fragalot: and about 1k in bearings ;)
03:35 PM fragalot: lol
03:35 PM Connor: Not with those motors. They're pretty big.
03:36 PM CaptHindsight: so like buying a small Chinese spindle
03:36 PM rmu: what about direct drive washing machine motors
03:37 PM rmu: (as servo, not as spindle)
03:37 PM gloops: theyre for washing machines
03:37 PM FinboySlick: rmu: I'm not sure the ODrive would run those too well.
03:38 PM Joe_Hildreth: JT-Shop: You are talking about the axis test on Stepconf? Or is there another tool?
03:38 PM rmu: in stuttgart someone tried to hook one up to stmbl IIRC
03:39 PM JT-Shop: Joe_Hildreth: the calibration tool in Axis
03:39 PM Deejay: gn8
03:40 PM JT-Shop: Calibration - Starts the Servo Axis Calibration assistant. Calibration reads the HAL file and for every setp that uses a variable from the ini file that is in an [AXIS_n] section it creates an entry that can be edited and tested.
03:41 PM JT-Shop: it says servo but you can change stepper things too so long as they are in the ini
03:42 PM Joe_Hildreth: JT-Shop: Thanks for the info. I will check that out when I get home tonight.
03:45 PM CaptHindsight: ah so the ODrive is a brushless DC motor drive? still not sure since the website skips that detail
03:47 PM CaptHindsight: https://docs.google.com/spreadsheets/d/12vzz7XVEK6YNIOqH0jAz51F5VUpc-lJEs3mmkWP1H4Y/edit#gid=0
03:48 PM CaptHindsight: what is the difference between an RC brushless motor and a brushless DC motor? Is there a definition of a RC brushless motor somewhere?
03:49 PM Connor: https://odriverobotics.com
03:50 PM FinboySlick: CaptHindsight: Taht's essentially what I was wondering.
03:50 PM Connor: No difference. Except maybe for the mounting.
03:50 PM CaptHindsight: so rather than expalin anything clearly I have to look at the schematics myself to make sense of wtf they are doing
03:50 PM Connor: They have both out runner and in-runner
03:51 PM CaptHindsight: thank you public schools!
03:51 PM FinboySlick: Connor in-runner/out-runner is magnet inside or outside the coils?
03:51 PM MarcelineVQ: the rc ones all seem to have quite open (to air) bodies as well
03:52 PM Connor: outrunner, the magnets are on the outside of the and they spin while the coils are stationary. in-runner, the magnets are on the shaft while the coils are on the outside.
03:53 PM Connor: in-runners look like traditional DC motors.
03:53 PM Connor: They're most common on RC cars.
03:53 PM Connor: out-runners are the ones for Drones..
03:54 PM Connor: I used one in my 3lb battle bot for it weapon.
03:54 PM gregcnc: RC motor are generally made as cheap as possible except for a few makes
03:55 PM Connor: Well.. some yes.. the competition ones aren't.
03:55 PM gregcnc: they are generally rated for short duration use and as light as possible often with large cooling holes
03:55 PM gregcnc: few will sacrifice a Neu like I did to make a spindle
03:56 PM FinboySlick: Well, time to go home. Have a good one people.
03:57 PM gregcnc: a few of the Chinese motors are pretty good
03:57 PM gregcnc: quite a few are junk, and then there is everything else
03:58 PM gloops: what would the advantage be of RC motor over purpose stepper motor?
03:58 PM gregcnc: power
03:59 PM rmu: speed if you need it
03:59 PM gloops: well those are real advantages, and the disadvantages?
03:59 PM gregcnc: Plain cables, large openings for coolant chip ingress are things you need to consider
04:00 PM andypugh: RC motors don’t give you any position control.
04:00 PM rmu: no real bearings. completely open. built for short term use.
04:00 PM rmu: you would need an encoder
04:00 PM andypugh: And tend to only give rated power if there is a huge great fan on the front.
04:01 PM CaptHindsight: andypugh: they put encoders on them, so noobs get to play with that fun
04:01 PM gregcnc: life isn't really a problem if decent bearings are installed
04:01 PM CaptHindsight: so it is for people who don't have much value for their time
04:01 PM rmu: low voltages mean huge currents
04:01 PM gregcnc: yes rating take into consideration the generally short operating time and large cooling available
04:02 PM andypugh: Talking of motors, do I need this? https://www.ebay.co.uk/itm/323221054636?ul_noapp=true
04:03 PM gregcnc: I vote yes
04:03 PM XXCoder: big 4th axis? or 5th axis?
04:03 PM MarcelineVQ: could make a rotating house
04:04 PM MarcelineVQ: keep the sun in your kitchen all day
04:04 PM andypugh: I made an offer of ÂŁ150 and he came back with ÂŁ175
04:04 PM CaptHindsight: nice rotary servo, might have a brake as well
04:04 PM andypugh: It isn’t obvious from the advert but the drive and programmer are included.
04:04 PM XXCoder: yeah just dont know how to configure
04:05 PM CaptHindsight: http://www.nsk.com/jp/services/download/manualpdf/C20137-01.pdf
04:05 PM XXCoder: doesnt really say if guy accessed and checked
04:05 PM gregcnc: 137nM stall torque
04:05 PM CaptHindsight: I'd get it at that price
04:06 PM CaptHindsight: the manuals decipher the part numbers
04:07 PM CaptHindsight: might have an absolute encoder
04:07 PM CaptHindsight: RS1010FN001 standard motor
04:08 PM CaptHindsight: page 23
04:08 PM rmu: harmonic drive?
04:09 PM CaptHindsight: ask for a clearer picture of the controller part number
04:09 PM andypugh: 40 kg!
04:10 PM andypugh: max 180 rpm, so I suspect there is a harmonium in there
04:13 PM andypugh: No, the catalogue says “Direct Drive” so I assume they are a high pole-count brushless.
04:13 PM rmu: aka stepper motor
04:14 PM andypugh: Except three-phase
04:14 PM andypugh: (Not that 3-phase stepper motors don’t exist)
04:16 PM CaptHindsight: no gears
04:17 PM andypugh: It looks like a fun thing, but at 40 kg I don;t know what I would so with it.
04:17 PM CaptHindsight: did you the spec for accuracy ion arc seconds?
04:17 PM andypugh: The encoder resolution is something like 614,000
04:18 PM andypugh: +/- 2.1 arc seconds repeatability, 60 arc seconds accuracy
04:20 PM andypugh: So, 0.02 degrees accuracy and 0.0005 repeatability, as I read it.
04:20 PM andypugh: I wish I knew what I wanrted it for
04:21 PM gregcnc: don't you have piles of stuff that really cool and just cheap enough to add to the pile?
04:21 PM rmu: mod your office chair
04:22 PM andypugh: gregcnc: Yes. I have lots of that sort of thing, like this blasted Faro arm I keep falling over :-)
04:23 PM gregcnc: I've reached the point where I pass stuff up
04:24 PM CaptHindsight: 4th 5th axis
04:25 PM CaptHindsight: wheel balancer
04:26 PM CaptHindsight: 3d print custom cake decorations
04:26 PM andypugh: I have a 4th axis. I am not sure that my mill table could lift 40kg. (Actually, I am sure that it can, but I would be very low on headroom under the spindle with that thing on top_
04:27 PM CaptHindsight: centrifugal cake icing remover
04:28 PM CaptHindsight: make a centerless grinder
04:30 PM andypugh: What I want to make is a slotting head for my mill, with a CNC-controlled rotation of the cutting bit.
04:30 PM andypugh: I am sure it would be ideal for cutting splines, and possibly shaping helical internal gears. If I ever needed to do that. Which I won’t.
04:37 PM CaptHindsight: nice motor for Archivist
04:38 PM CaptHindsight: hope he is happy and well
04:44 PM * jthornton just ordered a pound of grape pez...
04:44 PM andypugh: Not seen or heard from Archivist for a while
04:44 PM Jymmm: the candy?
04:45 PM Jymmm: andypugh: I heard there was some falling out?
04:45 PM andypugh: between?
04:45 PM Jymmm: I honestly dont know
04:46 PM CaptHindsight: I just heard that he was fine and working. he just left the webs and IRC's.
04:46 PM Jymmm: ah
04:46 PM Jymmm: ok
04:46 PM andypugh: Maybe he got a girl. You would never seem me again if that happened to me.
04:47 PM Jymmm: andypugh: grow me?
04:47 PM CaptHindsight: I printed 3 pages using Firefox from a website, they came out really tiny and in the upper left corner of the print...
04:47 PM Jymmm: one*
04:48 PM andypugh: CaptHindsight: That’s a punishment fro printing a web site rather than sending the URL
04:48 PM CaptHindsight: I go into the Firefox printer settings and the default was 16 pages per page :) obviously nobody checks this stuff before they release
04:49 PM Jymmm: forefoz printing kinda sucks much of the time sadly
04:49 PM gregcnc: my wife usually manages to print a paragragh on 16 pages
04:49 PM Jymmm: You have to go into READER mode
04:49 PM CaptHindsight: this is a new install of Fedora
04:50 PM CaptHindsight: haven't been surprised by all the default settings yet
04:50 PM CaptHindsight: gregcnc: hah, yeah, that is fun as well
04:56 PM jthornton: gregcnc: my wife prints all the blog comments when trying to print a recipe lol tons of pages
04:56 PM gregcnc: printing from the web is a nightmare. I PDF if I need it.
04:57 PM Jymmm: gregcnc: Even pdf priting from firefox is bad
04:57 PM Jymmm: from chrome is a bit better, but not by much
05:31 PM andypugh: Woot! up to date with the forum. It feels like a chore sometimes.
05:31 PM infornography: https://cdn.discordapp.com/attachments/442435176585232386/539949892572020746/ie4.gif
05:31 PM infornography: sometimes I miss the 90s internet
05:32 PM andypugh: Aye, I remember when there were only a dozen web-sites. (really!)
05:33 PM andypugh: We got an email at work saying “there is this thing called the world wide web, you need this software called “Mosaic” and you can type in these adresses. NCSA was obviously one, and CERN, and also the CIA World Factbook and the Vatican Library.
05:34 PM infornography: :O fancy
05:39 PM gregcnc: I watched a bit of the nat geo show valley of the boom https://www.nationalgeographic.com/tv/valley-of-the-boom/
06:13 PM CaptHindsight: gregcnc: what perspective is it from?
06:17 PM CaptHindsight: ah, it's not a documentary
06:40 PM ziper: CaptHindsight, have you done resin vacuum infusion before?
06:45 PM SpeedEvil: resin infusion is neat.
06:45 PM SpeedEvil: Only low vacuum here.
06:45 PM SpeedEvil: as of yet.
06:45 PM gregcnc: what are you making?
06:48 PM ziper: how do you make sure all the fiber actually gets wetter out?
06:48 PM ziper: wetted*
06:48 PM SpeedEvil: ziper: it's visually obvious when it's all wetted out if you use transparent stuff
06:48 PM ziper: carbon doesn't
06:48 PM SpeedEvil: yeah - that'd be less obvious.
06:49 PM SpeedEvil: Do you mean vacuum bagging, or pulling a hard vacuum with something submerged?
06:50 PM Tom_L: funny, i watched a 'how it's made' on carbon boots using that method
06:50 PM ziper: submerged in what?
06:50 PM Tom_L: vacuum baging
06:50 PM SpeedEvil: ziper: resin.
06:50 PM Tom_L: then injecting the resin in the bag
06:51 PM ziper: i've just been doing regular wet layup bagged after, but after reading more infusion looks rather nice
06:51 PM ziper: take your time setting up the fibers, less mess, less fumes, can use a faster cure resin, less resin consumption (?)
06:52 PM SpeedEvil: It's basically you use the quite large ~10PSI or whatever delta between the resin source and the porous layer to drive resin through the layup.
06:53 PM SpeedEvil: The porous layer gets 'choked' by the resin getting to it and mostly stops pulling, with only limited amounts flowing out through it into the mat that has a dual purpose of sopping up the resin and giving a space for the air to move.
06:54 PM ziper: I didnt think infusion used bleeder cloth
06:55 PM CaptHindsight: ziper: since I make epoxies, urethanes, polyesters etc. i can modify them to suit just about any application
06:56 PM Tom_L: https://www.youtube.com/watch?v=cprLcDcWk4U
06:56 PM CaptHindsight: if your epoxy is to high a viscosity and doesn't easily pull through you can try to heat it
06:56 PM Tom_L: 3:00 starts the bag process
06:56 PM CaptHindsight: but that might also accelerate the rate of cure
06:58 PM SpeedEvil: Just don't try to thin it. :)
06:58 PM SpeedEvil: Sigh.
06:58 PM ziper: oh man
06:58 PM ziper: they left the bag in the shoe
06:59 PM CaptHindsight: it gets messy but they could have coated the pieces of CF vs spray adhesive before bagging
06:59 PM ziper: and massaging the resin everywhere isn't exactly practicable on a boat
06:59 PM Tom_L: a guy i know here used to make boats too
07:00 PM Tom_L: he had a large vacuum compressor in the back of the shop he used when bagging them
07:01 PM CaptHindsight: I've noticed that lots of composite fabricators work with a very limited range of epoxies
07:01 PM ziper: I use the cheap stuff
07:01 PM CaptHindsight: they seem to order from the "epoxy warehouse" and thats as far as they go
07:02 PM ziper: I didn't know there were options
07:02 PM Tom_L: i've watched thru the window but never been in the composites lab at the vo-tech here
07:02 PM ziper: does anyone use anything besides BPA based?
07:02 PM Tom_L: they've got a pretty good size autoclave i know
07:02 PM CaptHindsight: ziper: we can blend it from thin as water to thick as clay
07:02 PM ziper: whats the thickener?
07:02 PM CaptHindsight: we even have water based epoxies
07:03 PM Tom_L: ot, i saw the dreamlifter take off with a load from spirit today
07:03 PM Tom_L: kinda eerie
07:03 PM CaptHindsight: ziper: it's not a thickener....
07:04 PM ziper: ok, what is the constituent that changes the thickness?
07:04 PM ziper: viscosity, rather
07:04 PM CaptHindsight: you just decide on which components to use to meet the specs you require
07:05 PM CaptHindsight: it's not that there is one "epoxy" base everyone starts out with and then adds thickener or thinner
07:05 PM ziper: is the more viscous stuff stronger?
07:05 PM CaptHindsight: I have epoxy components that are so thick that you can stand on top of the open drum at room temp
07:05 PM CaptHindsight: others are like water
07:07 PM CaptHindsight: ziper: it depends om how flexible you require it, tensile strength, glass transition temp etc
07:07 PM ziper: I have an application where i want to make a hinge. what resin should I use?
07:08 PM CaptHindsight: you might combine 2 components or 10 to formulate a blend
07:09 PM CaptHindsight: some epoxies cure as hard as a rock but are brittle
07:22 PM ziper: thanks. judging by the product descriptions -- no correlation
07:23 PM andypugh: easycomposited have some very good Youtube videos. There is a great one on going from 2D cad templates to 3D foam patterns, for example, using hand tools. (and it is a concept that scales as big as you want)
07:25 PM andypugh: In fact, here it is. Well made video and a very interesting process.
07:25 PM andypugh: https://www.youtube.com/watch?v=XeeSsmsm9h0&t=97s
07:25 PM CaptHindsight: https://www.smooth-on.com/products/flexer-epoxy-flexibilizer/
07:26 PM ziper: thanks andy
07:26 PM Tom_itx: where would we be without youtube
07:26 PM CaptHindsight: andypugh: how's that goin to bed by midnight going? :)
07:26 PM Tom_itx: heh
07:33 PM Tom_itx is now known as Tom_L
07:33 PM ziper: CaptHindsight, I assume you are familiar with fumed silica thickener?
07:33 PM CaptHindsight: ziper: yes
07:33 PM andypugh: Oh, that was yestrdays plan. And it was boring waiting to fall asleep at 3am as I always do
07:33 PM Tom_L: don't mess with a good pattern
07:33 PM ziper: how badly does it degrade the mechanical properties? Is it worth having already thick epoxy that only needs a little bit of silica to keep from sagging?
07:33 PM SpeedEvil: On a random note - does anyone have any thoughts on where to get cheap glass balls in the 100um range, of a consistent size, without having to sort them myself? I'm wondering about making vacuum spaced glass.
07:33 PM CaptHindsight: fumed silicas, glass spheres, hollow glass beads, glass fiber etc etc
07:33 PM CaptHindsight: ziper: depends on what you are starting with and where you want to go
07:34 PM CaptHindsight: SpeedEvil: ^^
07:35 PM CaptHindsight: and page 11
07:35 PM CaptHindsight: OK now tell me some of your secrets
07:36 PM SpeedEvil: CaptHindsight: I think I want solid - I have to do the numbers. Spread over a pane of glass, lay other pane of glass over it, seal edges, pump to hard vacuum.
07:36 PM CaptHindsight: SpeedEvil: all kinds of solid particles to use as fillers
07:36 PM CaptHindsight: silica, ceria, boron nitride, aluminum etc etc
07:37 PM CaptHindsight: SpeedEvil: making a laminate with epoxy and glass?
07:37 PM SpeedEvil: CaptHindsight: No.
07:37 PM CaptHindsight: oh as a mold?
07:37 PM SpeedEvil: CaptHindsight: no resin involved. Look at the pilkington spacia link. And glass, not glasfibre
07:37 PM SpeedEvil: Vacuum insulated windows.
07:38 PM ziper: what do the spheres do?
07:38 PM Tom_L: create space
07:38 PM SpeedEvil: ziper: stop the panes touching with 14PSI load
07:38 PM ziper: duh
07:38 PM CaptHindsight: ziper: hollow ones will thicken and lower the density of the resin
07:39 PM SpeedEvil: And make the resin stiffer, if you're doing that with them.
07:39 PM ziper: CaptHindsight, what determines cure time? why can't I just add more hardener like I can with polyester?
07:39 PM SpeedEvil: (for glass bubbles)
07:39 PM CaptHindsight: ziper: chemistry and temperature
07:40 PM CaptHindsight: ziper: are you using MEKP with polyesters?
07:41 PM SpeedEvil: ziper: if you add less or more hardner with epoxy, you do not get a reaction that goes to completion, and are left with some unreacted hardner or resin, which damages the properties.
07:41 PM SpeedEvil: (in general)
07:42 PM ziper: ok, and what is the difference in components that causes some epoxy mixes to be faster than others?
07:42 PM SpeedEvil: ziper: A magician has cast haste on it.
07:42 PM CaptHindsight: ziper: thats functionality
07:43 PM ziper: CaptHindsight, I only use polyester on cheap stuff, but I understand it well enough. i'm more interested in the epoxies
07:43 PM CaptHindsight: mono, di, tri, quad, octo etc
07:43 PM CaptHindsight: the epoxies will have branches that crosslink in parallel with each other
07:43 PM ziper: is that also inextricably linked to the ability of the resin to handle higher temperatures, both during and after curing?
07:43 PM CaptHindsight: more branches the faster it cures
07:44 PM ziper: I see, perfect explanation
07:44 PM CaptHindsight: that gets into the shape of the molecules
07:44 PM CaptHindsight: picture a zigzag epoxy vs straight line
07:45 PM CaptHindsight: the zigzag can stretch or compress
07:46 PM CaptHindsight: the temp an epoxy radically changes it's flex is a combo of factors
07:47 PM CaptHindsight: you mix different types to get what you want and or fillers
07:47 PM CaptHindsight: one component may easily flex at lower temps and 5%b of that in the formula may be what you want
07:47 PM CaptHindsight: in another 15%
07:49 PM CaptHindsight: so you blend all these soft. hard, low temp high temp components together to get what you want
07:50 PM CaptHindsight: and there's thousands of research papers on what people have tried with their results
07:50 PM CaptHindsight: sometimes it's intuitive, sometimes it's not
07:52 PM CaptHindsight: some suppliers have 10 or so basic components and they show you how to blend them to more or less of a feature
07:52 PM ziper: ok, i'm almost sated. About chemistry: am I correct that BPA is the most common one?
07:52 PM CaptHindsight: flex, hardness, tensile strength, higher/lower tg etc
07:53 PM CaptHindsight: likely
07:53 PM ziper: are there any others suitable for boatbuilding?
07:58 PM CaptHindsight: boats use a gel coat at the outer water barrier
07:58 PM CaptHindsight: most epoxies are not water soluble after cure
07:58 PM CaptHindsight: boat building is mostly cost driven
07:59 PM CaptHindsight: the resin and gelcoat suppliers have those down to near a commodity
08:00 PM ziper: and BPA is the cheapest?
08:00 PM CaptHindsight: http://www.interplastic.com/p-specialty_flexibleresins.php
08:01 PM CaptHindsight: likely acrylated epoxies are lowest cost
08:01 PM CaptHindsight: some are <$2/lb
08:03 PM CaptHindsight: https://www.alibaba.com/showroom/bpa-epoxy-resin.html
08:03 PM CaptHindsight: BPA looks ~$3/Kg so pretty close
08:03 PM CaptHindsight: $1.40/Lb
08:04 PM ziper: haha i'm sure thats high quality stuff
08:04 PM CaptHindsight: it works
08:05 PM CaptHindsight: if it's for industrial it's fine
08:05 PM CaptHindsight: just not FDA applications
08:05 PM ziper: even high performance stuff?
08:05 PM CaptHindsight: yes
08:06 PM CaptHindsight: they make cheap copies of just about everything
08:06 PM CaptHindsight: high perf tend to be high flex and that gets pricey
08:07 PM ziper: what about matching the properties of the epoxy to that of the fiber? I hear about it but I don't know what that actually entails
08:07 PM CaptHindsight: they don't make everything so US makers focus on $40/lb components that hardly anyone uses
08:08 PM CaptHindsight: or components that are cheaper to buy and make here vs ship from China
08:09 PM SpeedEvil: Edible scented epoxies.
08:39 PM norias: are we making carbonfiber stuff?
09:34 PM ziper: yes
09:36 PM ziper: norias, spars, hulls, hydrofoils
09:37 PM norias: HI
09:37 PM norias: sorry, had caps lock on for work stuff
10:02 PM CaptHindsight: I need to work on a CF weaving machine for non-planar composites
10:03 PM Tom_L: on what scale?
10:04 PM CaptHindsight: https://www.youtube.com/watch?v=rhRCtXcioiA
10:04 PM CaptHindsight: auto panel size
10:05 PM CaptHindsight: think insects, bees, spiders, silk worms
10:06 PM CaptHindsight: 9-axis winding https://youtu.be/IRuIR3uhkX8?t=63
10:06 PM roycroft: i weave tartan fabric on an old canadian jack loom
10:06 PM roycroft: that would probably not scale down to cf
10:07 PM CaptHindsight: CF yarn
10:09 PM CaptHindsight: 2D layers that are woven into 3 vs just a resin bond
10:10 PM SpeedEvil: shiny.
10:10 PM SpeedEvil: CF fabrication as your granmother would.
10:10 PM CaptHindsight: https://sc01.alicdn.com/kf/HTB1McNsRFXXXXcnXXXXq6xXFXXX6/Silk-cut-cocoon-Type-raw-silk-cocoon.jpg_350x350.jpg
10:11 PM * SpeedEvil wonders what the % chance is.
10:11 PM CaptHindsight: https://healdsburgshed.com/wp-content/uploads/2017/04/SHED_SUMMERHEADER_02-618x369.jpg
10:13 PM CaptHindsight: if you can build small CF extruders
10:13 PM SpeedEvil: Empty it out of honey, add plaster of paris, burnout, recast aluminium, use for honeycomb reinforcements.
10:13 PM SpeedEvil: 'made with real honeycomb'
10:13 PM CaptHindsight: same for DNA
10:14 PM CaptHindsight: tiny extruders
10:15 PM SpeedEvil: Come up with a electrically controlled array with ribosome or polymerase, and profit.
10:15 PM CaptHindsight: need more funding
10:19 PM CaptHindsight: a microscale silk extruder is much easier
10:19 PM CaptHindsight: but not as strong
10:20 PM CaptHindsight: but 3d silk composites could be made into complex shapes
10:22 PM CaptHindsight: https://inchemistry.acs.org/content/inchemistry/en/atomic-news/spider-webs.html
10:26 PM CaptHindsight: https://www.cam.ac.uk/research/news/green-method-developed-for-making-artificial-spider-silk
10:26 PM SpeedEvil: Silk is fucking complex alas.
10:28 PM SpeedEvil: https://www.kay.biochem.utah.edu/research/ - is neat. Attempting to make an oppositely chiral e.coli bacteria. _all_ the starting machinery has to be made artificially as you can't use anything biogenic.
10:44 PM CaptHindsight: roycroft: have a pic of your loom?