#garfield Logs
Jun 01 2020
#garfield Calendar
05:54 AM polprog: rue_mohr: possible way to test various cores? https://i.imgur.com/S0HuPuN.png
06:00 AM polprog: plots current vs B
06:00 AM polprog: they didnt draw which opamp input is which
06:00 AM polprog: typical
07:59 AM aandrew: hh
08:25 AM rue_mohr: I can tell you more later, its easy tho
09:04 AM polprog: i know which is which ;) its an intergating amp.. im just poking fun at the PhDs as usual
09:05 AM rue_mohr: :)
09:20 AM rue_mohr: wow my right ear is ringing like a banshee this morning
09:25 AM rue_mohr: polprog, have a filament transformer to use for that core tester?
09:25 AM polprog: you mean high current?
09:25 AM rue_mohr: low voltage, high current
09:26 AM polprog: not sure.. maybe i could make something up.. i have a toroidal 220V -> 12V one
09:26 AM polprog: i could wind a couple turns on it
09:26 AM rue_mohr: mhm
09:29 AM polprog: oh my. helping someone with C classes.. they have to write a function that integrates/differentiates a discrete function given as an array of xy pairs
09:29 AM polprog: the person who i am helping can't define a struct variable
09:29 AM rue_mohr: ouch
09:29 AM rue_mohr: how did the course make that leap?
09:29 AM polprog: mind you we are nearly done with the semester
09:29 AM polprog: the thing is - it did not
12:26 PM Tom_L: rue_mohr, going deaf?
12:27 PM Tom_L: better watch that... it only gets worse
12:57 PM aandrew: Tinnitus sucks. My left ear is completely fucked, and that’s the official medical term
12:59 PM aandrew: My left is -30dB down from nominal, at its best frequency. My right (and what left used to be) is about 0.5-1dB above nominal, so when my left gave out my brain decided to replace it with awful tinnitus
01:04 PM Tom_L: it happens
01:05 PM Tom_L: mine started with shooting pain down my neck then gradual loss
01:06 PM Tom_L: popped on a flight
01:53 PM aandrew: I think mine is not permanent. Every once in a long while I'll yawn or otherwise manipulate my throat/ear and perfect hearing comes back for a second. I can never make it stick but so far no ENT believes meand generally they're unwilling to do eustacian tube surgery because it's so invasive and has such a low chance of long term success
01:54 PM aandrew: two MRIs and there's nothing mechanically wrong with the inner ear nor brain, so that is good
02:35 PM Tom_L: yeah i had an mri too and they didn't find a gd thing except a bill
03:19 PM rue_shop1: great day so far
03:19 PM rue_shop1: *at work* i lost my van key (off my keychain) and the spare works, unless you try to remove it from the lock
03:51 PM polprog: grr, need a 75cm long rack
04:41 PM aandrew: rue_shop1: ouch
04:41 PM aandrew: Tom_L: yes I'm fortunate here that I didn't receive a bill for it
07:39 PM rue_mohr: aandrew, my tinnitus was louder than all hell today
07:40 PM rue_mohr: I couldn't hear the powder in an exitinguisher flowing over it
07:40 PM rue_mohr: }:/
07:40 PM Tom_L: find your keys?
07:41 PM rue_mohr: key
07:41 PM rue_mohr: *only* the van key fell off my keychain
07:41 PM rue_mohr: I got the new one out after working it a few times
07:42 PM rue_mohr: I could take the fob off, and without it the car wont start anyhow, but ARG
07:42 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Snapper/Knob6.jpg
07:42 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Snapper/Knob7.jpg
07:42 PM Tom_L: doesn't look much different but made a few changes
07:43 PM Tom_L: fixed the chamfers on the threads etc
07:43 PM Tom_L: added a section to my post
07:43 PM rue_mohr: so, you gonna make a tumbler to finish it? :)
07:43 PM Tom_L: i doubt it
07:46 PM rue_mohr: ok, after my nap, I'm gonna
07:46 PM Tom_L: learned a bit more about the program though
07:46 PM rue_mohr: program?
07:47 PM Tom_L: the cad cam
07:47 PM Tom_L: explored a bit
07:47 PM Tom_L: the thread macro works great
07:47 PM Tom_L: plopped it in the coordinates and it was just there
07:48 PM Tom_L: nice thing about a thread mill over a tap is it has good threads clear to the bottom
07:48 PM rue_mohr: cool
07:49 PM rue_mohr: how close does it get?
07:49 PM rue_mohr: CROSS SECTION!!!
07:49 PM Tom_L: the macro calculates to the bottom of the cutter so within 1 thread
07:50 PM Tom_L: i didn't feel like pushing it though
07:50 PM Tom_L: the hole was .700 deep and i went .650 on the threadmill
07:50 PM Tom_L: that's like 12 good threads or so
07:56 PM Tom_L: still haven't used them enough to get the tolerances just right. it was a bit snug so i think i should open it up maybe .005" or so over the major diameter
07:57 PM rue_mohr: I'v found I have to be carefull with the "1/8 inch " milling bits I have, they could be anywhere down to 2.89mm
07:57 PM rue_mohr: I guess the best thing is to mill a slot and measure it
07:57 PM Tom_L: i drilled it with a .250 endmill
07:58 PM Tom_L: then circular interpolated it up to the .257 for the drill size
07:58 PM rue_mohr: I want to work on my cam software
07:58 PM Tom_L: not sure it did that much
07:58 PM rue_mohr: just need a working gui lib
07:58 PM Tom_L: you _could_ be learing this one
07:58 PM Tom_L: and do anything you need done
07:58 PM rue_mohr: $$$
07:58 PM Tom_L: not from em
07:58 PM Tom_L: me
07:59 PM rue_mohr: I just want to import 2d profiles and do ops on them
07:59 PM rue_mohr: 2.5d
07:59 PM Tom_L: i have a 2.5d version too
07:59 PM Tom_L: never use it
07:59 PM Tom_L: just because this has 3d doesn't mean you gotta use it
08:00 PM Tom_L: but it is handy
08:00 PM Tom_L: nothing i did there was 3d
09:33 PM rue_mohr: polprog, core checker :) this will be a challange and your always going to be asleep when I'm available
09:42 PM Tom_L: heh
09:44 PM Tom_L: kid went to his cnc class for the first in a long time to finish up the 'hands on' part. when he had left the last time he had squared up his 'turners cube' and brought it home
09:45 PM Tom_L: he took it back with him today in his back pack and told the insructor he had done it at home. the instructor didn't believe him until he saw it
09:45 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Cube/Turners_cube2.jpg
09:45 PM Tom_L: also said they didn't have enough class time left to finish the project
09:46 PM Tom_L: so one of his class mates sent another block home with him tonight and guess what i get to do?
09:48 PM rue_shop1: heh
09:48 PM Tom_L: they worked on a set of dice today
09:48 PM Tom_L: his brother made a set when he went
09:50 PM Tom_L: kinda monotinous for him since he already works at a big cnc shop
10:01 PM rue_mohr: ok! I have another peiece to cad up
10:01 PM rue_mohr: 7 drawings open
10:09 PM Tom_L: what you workin on?
10:10 PM rue_mohr: brackets for holding the front panel of the resistor box
10:10 PM rue_mohr: I need to start thiking about what I'm supposed to be working on after the box
10:12 PM rue_mohr: I'm gonna glue the front panel to it, and it'll have screws from the case inward
10:15 PM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/main.png
10:16 PM rue_mohr: skelatonized with webbing is todays theme
10:17 PM rue_mohr: simple cheese eh?
10:17 PM rue_mohr: heh, it took me 16 minutes
10:17 PM Tom_L: sound about right
10:18 PM Tom_L: i'm a bit rusty with catia now. it would take me a bit longer probably
10:18 PM Tom_L: are those corners clear thru or just pockets?
10:18 PM rue_mohr: its 2 extrusions with a cylinder difference
10:19 PM rue_mohr: pockets
10:19 PM rue_mohr: matched on both sides
10:19 PM Tom_L: yup
10:19 PM rue_mohr: the web is 1mm thick in the middle
10:19 PM Tom_L: usually are
10:20 PM Tom_L: i would have started with that axis on the midpoint
10:20 PM Tom_L: but i know why you didn't
10:21 PM Tom_L: then you can extrude both directions either equally or unequally
10:21 PM Tom_L: openscad works alot different though
10:22 PM rue_mohr: http://ruemohr.org/~ircjunk/tempimage/profile.png
10:22 PM rue_mohr: thats a bad overlap of the two layers I extruded
10:23 PM rue_mohr: one with the pockets, one not
10:25 PM Tom_L: do you need the web in the pocket for strength?
10:26 PM rue_shop1: no
10:26 PM rue_shop1: its completely art
10:26 PM rue_shop1: as is the pocket
10:26 PM rue_shop1: :)
10:27 PM rue_shop1: I like skelatonized things
10:30 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/practice_drawings/Problem34_1.jpg
10:31 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/practice_drawings/problem34.jpg
10:31 PM Tom_L: i would be hard pressed to do those again in solidworks
10:32 PM Tom_L: although it is similar to catia
10:32 PM Tom_L: the constrains work a little different
10:32 PM Tom_L: different names etc
10:33 PM rue_mohr: the corner shamfers are what I cant do
10:33 PM rue_mohr: well easily
10:33 PM Tom_L: they taught us do do those on the solid, not in the sketch
10:33 PM rue_mohr: I think I'd have to do that with a huge difference list
10:33 PM Tom_L: but they're easy
10:34 PM rue_mohr: yea, you can just select the corners and tell it the radius, right?
10:34 PM Tom_L: and you can have variable corner radius'
10:34 PM rue_mohr: er, select edges
10:34 PM Tom_L: you can either pick a corner or 2 edges. it treats them differently
10:34 PM Tom_L: generally you want the corner intersect
10:36 PM Tom_L: and even though it takes longer they taught us to draw each feature on a separate drawing
10:36 PM Tom_L: that way it's easier later on to do modifications
10:37 PM rue_mohr: hmm
10:37 PM Tom_L: so you may end up with half dozen or more sketches for a simple part
10:37 PM rue_mohr: it occurs to me that a 3d printer has much more peace-of-mind to just walk away while it works than a cnc can
10:38 PM Tom_L: catia can group features and extrude them at different levels but they don't want us to use that feature
10:38 PM rue_mohr: hmm you cant really opent eh dxfs my program makes eh?
10:38 PM Tom_L: i probably can
10:38 PM Tom_L: is it openscad?
10:38 PM Tom_L: it's all triangles if it is
10:38 PM rue_mohr: I made all the drawings in 2d dxf and then use openscad to extrude place and do operations on in 3d
10:39 PM rue_mohr: just the dxfs
10:39 PM Tom_L: what do you use for the dxf?
10:39 PM rue_mohr: 2d
10:39 PM rue_mohr: librecad
10:39 PM Tom_L: not all dxf are created equal
10:39 PM rue_mohr: its more and more broken with every version
10:43 PM rue_mohr: I know
10:43 PM Tom_L: you want sw i got an old copy but you'd need a windows box
10:43 PM Tom_L: just like my cad cam
10:43 PM Tom_L: my original copy of my cad cam was dos
10:43 PM Tom_L: i still have it loaded
10:43 PM rue_mohr: yea
10:43 PM rue_mohr: my buddy there started to set it up
10:43 PM Tom_L: i know
10:43 PM rue_mohr: and then had 2 strokes
10:43 PM Tom_L: he would need my license file
10:43 PM rue_mohr: cant use most of his right side now
10:43 PM rue_mohr: broke him mentally
10:43 PM Tom_L: sorry to hear that.. i forgot his name now but i do remember
10:43 PM rue_mohr: he went by thejester
10:43 PM Tom_L: yeah
10:43 PM rue_mohr: life never gave him any breaks
11:15 PM rue_shop1: haha
11:15 PM rue_shop1: 3.0-0.5 != 3.5
11:21 PM MoonyMoon: hmm.
11:21 PM rue_mohr: M3 with 0.5mm deep threads