#linuxcnc Logs
May 26 2019
#linuxcnc Calendar
01:55 AM PL7icnc: CMorley, are you sir here online ?
01:59 AM CMorley: yes for a few mintes
01:59 AM PL7icnc: CMorley, the new Female on the forum seams to be buscan as he tries to get his system the hardway
01:59 AM PL7icnc: only 2 posts per tred
01:59 AM PL7icnc: no information on the system itself
01:59 AM PL7icnc: no ini or hal
01:59 AM Deejay: moin
01:59 AM CMorley: pretty hard to help that way hey :)
01:59 AM PL7icnc: Deejay, Guten Morgen Wahltag
01:59 AM PL7icnc: CMorley, you say it
02:00 AM CMorley: ok see ya
04:10 AM XXCoder: https://youtu.be/qx_qqVmjCc0 cool
04:22 AM XXCoder: that vuideo is pretty good so far.
04:34 AM XXCoder: https://www.youtube.com/watch?v=4aBVAbfxLJw epoxy granite. by same guy
05:38 AM Tom_L: morning
05:39 AM XXCoder: yo
06:12 AM jthornton: morning
06:14 AM XXCoder: yo
07:05 AM __rmaw is now known as rmaw
07:48 AM pink_vampire: morning
09:01 AM * jthornton is writing a C program to calculate sunrise and sunset
09:19 AM rmu: jthornton: don't reinvent the wheel, there are proven libraries for that. https://midcdmz.nrel.gov/spa/
09:20 AM JT-Shop: he is studying C
09:21 AM JT-Shop: and I will study that program too!
09:21 AM JT-Shop: thanks for the link
09:23 AM rmu: np
09:25 AM rmu: also, http://soltrack.sourceforge.net/
09:26 AM JT-Shop: that's cool
09:26 AM rmu: if your application is chicken door automation, correction for atmospheric abberation may be overkill ;)
09:26 AM JT-Shop: lol yea
09:42 AM perry_j1987: morning
09:42 AM perry_j1987: everybody got their coffee?
10:55 AM JT-Shop: it's nap time here
11:55 AM flyback: https://www.youtube.com/watch?v=eNSN6qet1kE
12:29 PM perry_j1987: little 3in milling vise arrived
12:35 PM pink_vampire: take a pic how it fit on the mill
12:36 PM pink_vampire: (if we can say mill on 6040) lol
12:36 PM perry_j1987: lol
12:36 PM perry_j1987: its "cute" for sure hah
12:37 PM perry_j1987: took the rotating plate off for it to fit etc
12:38 PM pink_vampire: it is a very good base for a lamp
12:39 PM pink_vampire: those are my emco vise next to 123 block https://i.imgur.com/ZD4qQo1.png
12:40 PM pink_vampire: here is my desk lamp https://i.imgur.com/ZEuhTWr.jpg
12:40 PM perry_j1987: hah you wernt joking
12:41 PM perry_j1987: now i need to finish this vise stop
01:38 PM perry_j1987: i do believe the new vise is swept in with my crapy dial indicator heh
01:58 PM JT-Shop: double check it with a wooden yardstick and a tape measure
02:01 PM pink_vampire: LOLLL!!
02:10 PM perry_j1987: JT-Shop i was using the scale on the back of my leatherman of course
02:11 PM perry_j1987: :P
03:46 PM Deejay: gn8
03:59 PM andypugh: Crikey, I just sold a 9-year-old, broken, PC on eBay for ÂŁ176,
04:03 PM jthornton: wow!
04:03 PM jthornton: was it a collectors item and you failed to notice that?
04:07 PM perry_j1987: did it have a parallel port ? :P
04:09 PM andypugh: No. Not even any PCI slots: https://www.ebay.co.uk/itm/Apple-iMac-A1312-27-Desktop-May-2011-SPARES-OR-REPAIR/113755098321
04:10 PM andypugh: Did you see my 5120 x 2880 tkLinuxCNC screenshot? :-)
04:11 PM andypugh: I could do that because I bought a 5k resolution iMac to replace the broken one.
04:20 PM sync: andypugh: I tried that before, all the linuxcnc stuff does badly with hidpi
04:22 PM andypugh: Well, it works but looks a little lost: https://forum.linuxcnc.org/51-ot-posts/35943-probably-the-bigest-linuxcnc-screenshot-ever?start=10#132219
04:23 PM sync: yes, I had the same issue on 4k
04:58 PM XXCoder: andypugh: did you hard wipe hard drive?
04:58 PM XXCoder: sometimes people buy shit pcs in order to harvest data off formatted but not hard erased drive
05:11 PM perry_j1987: hmm
05:12 PM perry_j1987: so playing with this bit of brass plate
05:17 PM jthornton: on a noaa spreadsheet for sunrise and sunset they have a column Sunrise Time (LST) which has a span of 0-1 anyone know what (LST) means in that sense?
05:20 PM roycroft: probably local sidreal time
05:20 PM Tom_L: local standard time
05:21 PM Tom_L: "LST/LDT" (Local Time with adjustment to Daylight Saving Time as appropriate)
05:21 PM Tom_L: “LST” (Local Standard Time, no adjustment for Daylight Saving)
05:23 PM jthornton: the range is 0 - 1
05:24 PM Tom_L: maybe 0 is LST and 1 is LDT?
05:24 PM Tom_L: not sure
05:25 PM jthornton: yep looks like Local Sidereal Time
05:27 PM jthornton: whatever the heck that is lol
05:29 PM Tom_L: with respect to the distant stars (i.e. the constellations or fixed stars, not the sun or planets).
05:30 PM Tom_L: gettin a bit far fetched for a chicken coop door :D
05:31 PM jthornton: lol, just using that as excuse to refresh me in C programming
05:31 PM andypugh: XXCoder: In fact I took out my SSD, put back in the oriiginal splinning-rust drive then erased that at level 3. “Security Option 3 - This option is a DOE-compliant 3-pass secure erase. It writes 2 passes of random data followed by a single pass of known data over the entire disk. It erases the information used to access your files and writes over the data 3 times.”
05:31 PM XXCoder: nice :)
05:32 PM jthornton: wow
05:35 PM jthornton: trying to write a C program you can supply the date and latitude and longitude and get the sunrise and sunset
05:35 PM SpeedEvil: Easy apart from timezones.
05:36 PM SpeedEvil: You basically need to look it up in a database that is no older than several weeks to be accurate.
05:36 PM SpeedEvil: (as it can undergo unpredictable legislative change)
05:36 PM jthornton: and how would you put the database in the chicken coop?
05:37 PM jthornton: easy to calculate sunrise and sunset for any given day and place?
05:38 PM jym: They call it an almanac
05:38 PM XXCoder: jthornton: maybe just get entire year worth of sunrises/sunsets graph it to get equation
05:38 PM XXCoder: then use that equation to calculate. it probably will have small error but dont matter
05:39 PM XXCoder: regression process
05:39 PM jthornton: I don't think a micro processor can read an almanac...
05:40 PM XXCoder: nah finding equation you find it on computer
05:40 PM jthornton: XXCoder: it needs to be able to calculate the sunrise and sunset based on location and date for years to come
05:40 PM jym: ts = 2/15 arccos (–tan φ tan δ)
05:40 PM XXCoder: yeah but then earth dont suddenly change times
05:41 PM jym: jthornton: https://aa.usno.navy.mil/faq/docs/rs_solstices.php
05:41 PM XXCoder: right! not linear regression but least squares
05:42 PM XXCoder: power of 2 is plenty to match curve of sunlight hours.
05:43 PM SpeedEvil: Or just +-128 minutes of correction in a 32 element table.
05:43 PM SpeedEvil: (every 12 days or so)
05:43 PM jym: jthornton: https://aa.usno.navy.mil/faq/docs/rs_algor.php
05:43 PM XXCoder: how to use excel to do it: https://math.slu.edu/~may/ExcelCalculus/sec-1-5-IntroBestFitCurves.html
05:44 PM jym: cradek: You might like this https://aa.usno.navy.mil/faq/index.php
05:44 PM jthornton: jym: https://aa.usno.navy.mil/faq/docs/SunApprox.php
05:45 PM XXCoder: looks like someone already did work for you
05:45 PM jthornton: that's pretty close to another paper I found
05:46 PM jym: jthornton: Do you think the chickens would might the slight deviation?
05:46 PM jym: mind*
05:47 PM jthornton: the key thing is to open the door at a time you want relative to sunrise and close the door at the time you want relative to sunset or dusk
05:47 PM XXCoder: yeah thats why I was talking about finding equations for sunrise and equation for sunsets
05:48 PM XXCoder: that way you can just calculate times
05:48 PM jthornton: chickens can't see in the dark so without supplemental lighting after dusk they don't move.
05:48 PM XXCoder: so no database at all, just 2 equations.
05:48 PM jym: chicken coop runway lights?
05:48 PM jthornton: not sure I know what you mean, it's different at different locations
05:49 PM XXCoder: yyou make equations from data for your location
05:49 PM jthornton: no, it has to be for any location not just where I'm at
05:49 PM jym: jthornton: (was kidding about the "...accurate to within 200 year deviation"
05:50 PM XXCoder: your link does just that which is nice
05:52 PM XXCoder: erm I meant jym's lol
05:52 PM XXCoder: no yours jt i cant read worth shit
05:53 PM jthornton: which link
05:53 PM jthornton: lol
05:53 PM jym: XXCoder: Nah, jthornton found that one
05:53 PM XXCoder: its good for 400 years
05:53 PM XXCoder: plenty of life
05:58 PM jthornton: dang ; is a pia with C lol
05:58 PM XXCoder: nahh you love it ;)
06:03 PM jthornton: yea I do actually, I think this is the first time I had an actual project to do in C
06:04 PM XXCoder: c is so simple, but its also so easy to shoot your foot with it
06:04 PM XXCoder: remember to releqase any malloc and stuff
06:05 PM jthornton: I've not done any malloc yet, I know it has something to do with memory but that's all
06:06 PM XXCoder: its way to get memory space to store whatever you need
06:06 PM XXCoder: but honestly your project dont need em at all
06:06 PM jthornton: yea it's pretty simple
06:07 PM XXCoder: one difference about malloc is it does NOT release at any time even after closing program. thats memory leak
06:07 PM XXCoder: so if you use it, you have to release it at some point before closing,.
06:07 PM jthornton: ah
06:07 PM jthornton: thanks for that info
06:08 PM jthornton: this is what I have so far https://paste.ubuntu.com/p/jtcdzDgCSs/
06:09 PM jthornton: the last few lines are not finished
06:09 PM jthornton: as in no ;
06:09 PM XXCoder: looks fine so far
06:09 PM XXCoder: you do comments very good
06:10 PM XXCoder: only difference between your style and mine is I really like to make order of ops very explict
06:10 PM XXCoder: ie use more ( )
06:10 PM XXCoder: its just style differences however
06:11 PM perry_j1987: hmm i need to mill a bunch of 5mm holes 1 inch deep. or should i only think about doing this with twist drills
06:11 PM jthornton: yea if I'm making the equation I am more specific but I'm copying equations
06:11 PM perry_j1987: 1/8 endmills vs twist drills for this i mean
06:12 PM XXCoder: why not both?
06:12 PM jthornton: drills are for holes, endmills are for milling shapes
06:12 PM XXCoder: drill to slightly bigger than endmill, use endmill to finish to precise size
06:12 PM XXCoder: very common at work
06:12 PM jthornton: if I need a metric hole I drill it just undersize then mill it to size
06:13 PM XXCoder: really comes down to this - whats your holes tolence?
06:13 PM XXCoder: +- .03" or even larger just use drill
06:13 PM perry_j1987: less tool change if could just helix down with 1/8 endmill though?
06:13 PM XXCoder: does your part depend on inside finish? need to be very smooth? either reamer or mill it
06:13 PM XXCoder: then lap
06:14 PM XXCoder: toolchanging if manual can be a concern yeah. helix can be done, but smaller diameter than final, then do final pass
06:14 PM XXCoder: assuming your endmill has 1" flute or more
06:15 PM perry_j1987: ya i was just peeking on amazon for 1/8 endmills with 1" flute
06:15 PM perry_j1987: thats not for wood and plastics heh
06:15 PM XXCoder: i work as metal cnc machinist, never wood and only rarely plastics lol
06:16 PM perry_j1987: ah nice.
06:16 PM perry_j1987: I just got a 6040 cnc router and forcing it to cut some metals :)
06:17 PM XXCoder: it can be strong enough for alum I think? i have one cnc router but my use for those is for wood artworks onlky, (home use)
06:17 PM XXCoder: work is all big machines heh
06:17 PM perry_j1987: i just got a little 3 inch milling vise in the mail today
06:17 PM perry_j1987: its installed on the 6040 now
06:17 PM andypugh: jthornton: Import Astral?
06:18 PM jthornton: in C?
06:18 PM jthornton: I use Astral in python now
06:18 PM andypugh: That part might need a shim layer
06:18 PM andypugh: https://people.sc.fsu.edu/~jburkardt/c_src/analemma/analemma.html
06:19 PM perry_j1987: hoping to one day see an endmill through to its end of useful life and not see it fly off into oblivion haha
06:19 PM andypugh: May not actually be what you need.
06:19 PM andypugh: perry_j1987: I never have.
06:21 PM jthornton: doesn't look like what I'm trying to do
06:22 PM perry_j1987: i'll see if I have any er collets that are right size to hold the drillbits and try that route first
06:31 PM XXCoder: cool
06:54 PM andypugh: Working on muy next youtube video. I fear it is going to be _much_ too long for anyone to bother watching.
06:54 PM XXCoder: like `10 whole minutes? your videos tend to be short ;)
07:06 PM perry_j1987: this 6040 is severely lacking in z height heh
07:40 PM Tom_L: andypugh, just make it uber cool and we will
08:00 PM cgi: are any of the desktop CNCs good these days? I am looking to cut carbon fiber + aluminium?
08:09 PM Tom_L: i took the route of diy
08:12 PM cgi: Tom_L, I dont mind paying a bit for getting something decent - unless its exorbitant
08:45 PM SpeedEvil: cgi: https://www.pocketnc.com/pocketnc/pocket-nc
08:45 PM SpeedEvil: Don't know what you think exhorbitant is, and how robust your desk is.
08:45 PM cgi: SpeedEvil, those dont cut CF if i am not mistaken?
08:46 PM andypugh: They cut aluminium. CF is just a matter of the right tooling.
08:46 PM andypugh: (I think)
08:46 PM gregcnc: they cut anything, it's just how fast you need it done
08:46 PM andypugh: Why is “desktop” important?
08:47 PM cgi: andypugh, cf also needs a waterbath - unless I want to die sooner :)
08:47 PM cgi: andypugh, I just need something compact, not the current 6 ft ^3 I am using in the house.
08:47 PM andypugh: That’s the problem with desktop. Get a non-desktop and it can live in an enclosure.
08:47 PM SpeedEvil: Strong extraction may be a reasonable alternative.
08:48 PM SpeedEvil: Ah - well - if you think 6ft^3 is big, that's your first problem with machine tools.
08:48 PM SpeedEvil: More seriously - what are you trying to make, at what speed?
08:49 PM SpeedEvil: 100mm quadcopter frames, or carbon carbon composite reentry nosecones?
08:49 PM cgi: SpeedEvil, I need to cut CF - to put in a diy fixed wing plane
08:49 PM SpeedEvil: Of what scale?
08:49 PM cgi: 3ft x 2ft cut area
08:50 PM andypugh: Waterjet?
08:50 PM SpeedEvil: Is there such a thing as a non-exhorbitant waterjet?
08:50 PM cgi: andypugh, I've never used waterjet - are they accessible?
08:50 PM cgi: SpeedEvil, exactly.
08:51 PM SpeedEvil: $50K+ AIuI
08:51 PM SpeedEvil: And I don't know if small ones exist.
08:51 PM gregcnc: airplanes aren't exactly cheap either?
08:51 PM andypugh: https://shop.wazer.com/products/wazer?variant=27069026376
08:51 PM cgi: My budget is < 10k for sure
08:51 PM SpeedEvil: Is that teh kickstarter one?
08:51 PM gregcnc: unless we're talking toy planes
08:51 PM SpeedEvil: If it's that one, it's comedically slow cutting, and the abrasive cost is murderous for that reason
08:52 PM cgi: I was just looking at that
08:52 PM andypugh: Yes. Do _not_ take me mentioning it as a recommendation. I know it exists, and that’s all I know.
08:53 PM andypugh: Also, “Reservations placed today are expected to ship April 2019.” isn’t a good sign.
08:53 PM SpeedEvil: - I was looking at it at the time it was kickstarted, and the performance at that point was terrible for anything other than a machine to sit on your desk and make the very, very occasional cut
08:54 PM andypugh: Anyway…
08:55 PM cgi: What is a good machine to cut CF today?
08:55 PM cgi: Make - > Gave it an editor's choice! Wazer
08:55 PM SpeedEvil: What sorts of CF cutting are you doing? Purely cutting sheet?
08:56 PM cgi: SpeedEvil, yes, sheets only for now
08:57 PM SpeedEvil: may interest https://blog.patshead.com/2019/02/cutting-carbon-fiber-sheets-on-my-shapeoko-cnc.html
08:57 PM cgi: SpeedEvil, https://protomax.com - here is another waterjet
08:58 PM SpeedEvil: The pump size looks light.
08:59 PM SpeedEvil: Take that .25lb/minute abrasive requirement, and look up the cutting speed, and convert to $abrasive/in of cut
09:02 PM SpeedEvil: I can't see cut speeds broken out
09:04 PM cgi: could not find the pricing
09:05 PM SpeedEvil: Garnet is not particlarly expensive - $1/kg. But if you're doing an inch a minute, that rapidly adds up.
09:06 PM ziper: cgi, sandwich laminate?
09:07 PM cgi: ziper, laminate
09:08 PM ziper: any core?
09:12 PM cgi: ziper, probably not - but not sure
09:14 PM cgi: ziper, do you play with CF? cnc?
09:29 PM XXCoder: whew
09:29 PM XXCoder: so much yard work
09:32 PM roycroft: it was supposed to be sunny and warm today
09:32 PM roycroft: it was rainy and cool
09:32 PM roycroft: so no yard wark
09:32 PM roycroft: work
09:33 PM XXCoder: you got lucky lol
09:33 PM XXCoder: here it was supposed to rain but sunny
09:33 PM roycroft: my belt grinder stand is in primer now, and i've finished assembling the drawers for my lathe stand cabinets
09:33 PM ziper: cgi, CF yes, but not machining it, yet
09:33 PM roycroft: and my main shop is somewhat less cluttered than it was
09:33 PM roycroft: i'm brewing next weekend for the country fair, and have a lot of shop cleanup to do before i can do that
09:34 PM roycroft: so i took the inclement weather as an opportunity to do some catching up on other things
09:34 PM cgi: ziper, did you make some CF yourself yet?
09:34 PM ziper: yes
09:35 PM ziper: well, mostly repairs
09:35 PM ziper: a few parts