#robotics Logs

Dec 25 2017

#robotics Calendar

01:10 AM rue_mohr: ok I think I figured out internet securrity
01:13 AM rue_mohr: all the wbsites you see are not the actual websites but proxies by caching servers (its true)
01:13 AM rue_mohr: and they do this by hysting the dns entries for the server names
01:13 AM rue_mohr: BUT to keep people from just using ip addresses etc and accessing the REAL sites, they need to put 'anti spoofing' protection in that illigitimizes the real servers
01:13 AM rue_mohr: :-| armyofevilrobots ?
01:13 AM rue_mohr: a few times I'v run into situations where the proxying server broke
01:13 AM rue_mohr: mostly with thingiverse
01:34 AM rue_mohr: anonnumberanon, well, I still have the lye, so I can do a test tommorow, and if it all works out, photoetch more aluminum involute gears
01:35 AM anonnumberanon: What is a lye
01:37 AM rue_mohr: base
01:37 AM rue_mohr: not acid
01:37 AM anonnumberanon: Oh
01:37 AM rue_mohr: etches aluminum
01:37 AM rue_mohr: I have a backup of things to make
01:38 AM anonnumberanon: Well i have to clean up parents garage then will also be unboxing my new drill press
01:38 AM rue_mohr: I got the idea that if I take a thin clear backer, and fix on a layer of aluminum foil, I can make etched encoder wheels
01:38 AM anonnumberanon: Oh yeah what do u use for the lense to detect encoding edges?
01:39 AM rue_mohr: I have some UV nail polish, so, photoetching pcb's... and encoders, and gears,
01:39 AM rue_mohr: I'll play
01:49 AM rue_mohr: dcleadscrewmath.xls
01:49 AM rue_mohr: huh
01:12 PM Tom_L: rue_mohr
01:12 PM Tom_L: you got land behind your house to build don't you?
01:12 PM Tom_L: before scrapping the old one..
01:16 PM rue_mohr: only if use 1/4 of the land as a driveway
01:17 PM rue_mohr: the only practical place to put a house is where the existing one is
01:19 PM Tom_L: how's that gonna work?
01:20 PM rue_mohr: I'm sure it wont be the biggest problem
01:21 PM Tom_L: kinda bored today. nothing really i can work on
01:21 PM rue_mohr: so, shows the spindle go on your existing sherline
01:21 PM rue_mohr: the motor on the one I have it bolted to it
01:22 PM rue_mohr: off an L bracket
01:22 PM Tom_L: the spindle will probably be the last major thing to go in
01:23 PM rue_mohr: right...
01:23 PM Tom_L: so i can align it with the rest of it
01:23 PM AchiestDragon: its xmas , ant we supposed to be singing carrols or something ...,,, as we go snorkeling in the snow, as to day is not that cold , with the wind that strongly blows the carrol word sheet , look there off it goes ...... well at least thats over
01:23 PM rue_mohr: I can count the flakes that fell last night
01:23 PM rue_mohr: done, 26
01:23 PM Tom_L: i can't
01:23 PM Tom_L: there weren't any
01:24 PM rue_mohr: it happened after midnight, therefore it did snow on cristmas
01:24 PM AchiestDragon: well most, infact all of the snow here was in liquid form
01:25 PM rue_mohr: ah, shovel free
01:26 PM rue_mohr: if I go somehere for vaccation next year, is china or usa a better trip ya think?
01:26 PM rue_mohr: shenzeng or ...
01:26 PM * rue_mohr looks at tom
01:26 PM rue_mohr: alabama?
01:26 PM Tom_L: you might have to fill a boat of your own if you went to china
01:26 PM rue_mohr: :)
01:27 PM rue_mohr: I wonder if I'm allowed to come back in a shipping container of my stuff to save travel fee's
01:27 PM rue_mohr: I hear that getting a whole container brought over isn't that expensive
01:27 PM Tom_L: then you could convert the container to a house too
01:28 PM rue_mohr: na, the last people did that and now I'm stuck with having to get rid of it
01:28 PM Tom_L: https://www.curbed.com/2017/6/21/15839730/shipping-container-house-for-sale-buy
01:29 PM theBear: chop it up with yer biggest ankle-biter and build a tank outta it
01:29 PM theBear: Tom_L, yeah, but what they charge for delivery ? that's how they get yer <wink>
01:29 PM rue_mohr: pass, I could hold onto it and use it for storage for all the stuff in my house while I build a new one
01:32 PM Tom_L: i wonder if i ended up with one of those chinaco spindle heads, what sort of motor i should look for for it
01:32 PM AchiestDragon: they make for good rfi/emp shelded datacenter enclosures / rf testing workshops , as there basicaly a farraday cage
01:32 PM Tom_L: i've got spindle out control right now at 0-10v
01:32 PM Tom_L: not the industrial standard -10 +10
01:34 PM rue_mohr: -10 - 10? odd
01:35 PM Tom_L: it's normal for industry
01:35 PM rue_mohr: all the 10V related stuff I'v seen is 0-10
01:35 PM rue_mohr: things are either 0-10 or 4-20mA
01:35 PM Tom_L: https://www.ebay.com/itm/ER25-Spindle-Head-1-5KW-2HP-Power-Head-Unit-5Bearings-3000rpm-Drilling-Machine/201707809248?_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D49451%26meid%3D7786596898c94b02b6467bdba576c07e%26pid%3D100675%26rk%3D13%26rkt%3D15%26sd%3D142265346587&_trksid=p2481888.c100675.m4236&_trkparms=pageci%253A9d05e231-e9aa-11e7-a462-74dbd1808d6c%257Cparentrq%253A8f2b40461600aa472ce394b1ffe5f3ff%257Ciid%253A1
01:35 PM Tom_L: something to drive something like that
01:35 PM rue_mohr: yea no
01:36 PM rue_mohr: but, sherline
01:36 PM Tom_L: the sherline head wouldn't hold up
01:37 PM rue_mohr: no, but you said for temp?
01:37 PM rue_mohr: I Plan to play with one of those washing machine brushless
01:37 PM rue_mohr: iirc is the seals and bearings that give out on the machines, not the motors
01:38 PM Tom_L: no, the sherline is temp
01:39 PM Tom_L: you said you went thru brushes on the sherline already
01:39 PM Tom_L: i have a spare sherline motor
01:39 PM rue_mohr: ok...
01:39 PM Tom_L: it's the one that has internal brushes
01:39 PM rue_mohr: armyofevilrobots, said that he'd put a lot of hours on it since he got it, used.
01:39 PM Tom_L: oh
01:39 PM rue_mohr: yea, they weren't that bad to change
01:39 PM Tom_L: it might do fine
01:40 PM Tom_L: the new one has external brushes
01:42 PM AchiestDragon: you should look for the shaft that has a r8 spindle , that way it will take bridgeport tools , as when it comes to use getting tooling to fit is quite easy
02:35 PM rue_mohr: not mt2 / 3?
03:14 PM edmoore: good
03:15 PM edmoore: got it k-lined by freenode staff
03:15 PM edmoore: and breathe
06:54 PM rue_mohr: daaamnit
06:54 PM rue_mohr: I only missed it by 4 hours
06:54 PM rue_mohr: Tom_L, ?!
06:54 PM rue_mohr: not worth register only, cause that setting is more of a pain in the ass than the freq of ^ that
06:58 PM -!- #robotics mode set to +o by rue_mohr
07:14 PM Tom_L: got enough ops here ya think?
07:15 PM -!- #robotics mode set to -o by Tom_L
07:15 PM Tom_L: i dumped it from the logs though
07:18 PM Tom_L: wasn't here either
07:20 PM mrdata-: goodness, i missed the holiday spam\
07:21 PM Tom_L: it's an on going thing with him and freenode
07:52 PM rue_shop3: we just need one of us here when the spammer hits
07:52 PM rue_shop3: block the whole isp subnet if you can
07:52 PM Tom_L: doesn't happen that often
07:52 PM rue_shop3: so, etching aluminum with lye, REALLY WEAK concentration is just fine...
07:53 PM rue_shop3: no, but their on the rampage now
07:53 PM Tom_L: generally once a year
07:54 PM Tom_L: gonna be pretty coarse gears won't they?
07:55 PM rue_shop3: photoetched?
07:55 PM rue_shop3: the test with normal nailpolish failed tho, it came off
07:55 PM rue_shop3: the lye MIGHT soak thru it
07:55 PM rue_shop3: see how long it takes to etch
07:56 PM Tom_L: how thick?
07:57 PM Tom_L: it's probably gonna etch on a taper
07:58 PM rue_shop3: right now I'm playing with tinfoil for making encoder wheels
07:59 PM Tom_L: try some aluminum duct tape then it will already have the adhesive backing
08:00 PM rue_shop3: heh
08:00 PM rue_shop3: I'm using a ridgid clear backing
08:00 PM Tom_L: you know the stuff...
08:00 PM rue_shop3: glue, and tinfoil
08:00 PM rue_shop3: see what I win
08:02 PM rue_shop3: huh, LOTS of bubbles, verry little etching action
08:06 PM mrdata-- is now known as mrdata-
09:10 PM rue_shop3: huh, lots of bubbles then they stopped, and nothing was etched...
09:11 PM mrdata-: using what
09:11 PM mrdata-: on what
09:23 PM Tom_L: Aluminium reacts with lyes to produce hydrogen gas. Since hydrogen is flammable, mixing a large quantity of a lye such as sodium hydroxide with aluminum in a closed container is dangerous—especially when the system is at a high temperature, which speeds up the reaction.
09:23 PM Tom_L: Dissolve the Aluminum. Place the pieces of aluminum foil in a 250 mL beaker. Measure out 5 mL of 1.4 M KOH in a graduated cylinder. Then pour the KOH solution into the beaker containing the small pieces of foil.
09:36 PM mrdata-: i ran this to dissolve quite a lot of aluminum
09:37 PM mrdata-: eventually making rather nice Al(OH)3
09:37 PM mrdata-: powder
09:39 PM mrdata-: it worked well in hot water
09:42 PM mbrumlow: I am struggeling
09:43 PM mbrumlow: struggling ... wiht figuring out where my logic should live
09:43 PM mbrumlow: i knew it was a bad idea to try and use irssi over ssh on a tiny phone.
09:45 PM mbrumlow: i have always thought i would have things like collision detection in a low layer and only report higher order info up
09:47 PM mbrumlow: i have alwasy felt it was not a good idea to push all thr sensor data to a linux system and just deal with it as fast as i could.
09:49 PM mbrumlow: i am trying to find that line. are there any good books talking about this subject?
09:53 PM mbrumlow: for example, i could wire up a motor controller and encoders to a rpi3 and have all thr logic live there. Or i could make a custom driver that only exposes a higher level api to thr rpi3.
09:54 PM Tom_L: always choices to make
09:55 PM mbrumlow: where the rpi3 is not worried about things like encoders and can only have simple control over rpm
09:56 PM mbrumlow: are there standards for this ?
09:57 PM Tom_L: not that i'm aware of
09:57 PM mbrumlow: maybe thr rpi onky has controls to set speed and a heading offset
09:59 PM mbrumlow: hmm well thanks, seems i have more to think about
10:00 PM Tom_L: my cnc offloads data to a fpga and the fpga does all the pwm etc
10:04 PM mbrumlow: yeah thst seems like the sort od minimum thst i dont feel should be handled by a non real time system
10:15 PM Tom_L: the control is rtai linuxcnc
10:16 PM Tom_L: rue_shop3, what do you use for limit switches on your mill?
10:16 PM Tom_L: mbrumlow you haven't said what you're controlling
10:47 PM mbrumlow: Tom_L a robot
10:47 PM rue_shop3: my origional uses switches, that are half the stop, the other half is a rotary encoder, 1 pulse
10:47 PM mbrumlow: i have not built yet
10:47 PM rue_shop3: that way I know I'm at the right point in the rotation of the stop
10:47 PM rue_shop3: BUT
10:47 PM rue_shop3: my last machines does not use limit switches
10:48 PM rue_shop3: there is no homing
10:48 PM rue_shop3: the home is where you set it up on the job
10:48 PM Tom_L: i just got some cheap ones for now
10:48 PM Tom_L: mostly for home limits
10:48 PM Tom_L: i'll use soft limits for the actual box
10:48 PM rue_shop3: repraps tend to just use microswitches, people swear by them, I'v had my issues
10:48 PM Tom_L: like i do now
10:49 PM Tom_L: these are just cheap microswitches
10:49 PM rue_shop3: do you have fixed machine positioning on yours?
10:49 PM Tom_L: on the sherline i home it before i start
10:49 PM rue_shop3: I have the thought that 'crash' switches could be good
10:49 PM rue_shop3: I use the pendant to put it to my 0,0
10:49 PM rue_shop3: everything goes from there
10:49 PM Tom_L: well so do i but after setting the machine zero limits
10:50 PM Tom_L: i use G54 as the offset for machining
10:50 PM Tom_L: once it's set i tell it to go to zero and it goes to the corner of the vise or whaever
10:50 PM rue_shop3: yea, it a new method for me, my origional machine homes for each job, then you ssssssssssssllllllllllloooooooooooooooowwwwwwwwwwwwwwwwyyyyyyyyyyyyy move it to your 0,0
10:51 PM rue_shop3: did I mention that the homing isn't fast either?
10:51 PM Tom_L: mine rapids to home
10:51 PM rue_shop3: mine to, but its old, unipolar voltage drivers, its full speed jog is about 1.5ipm
10:53 PM Tom_L: i'm gonna switch my limits over to an 8pin din plug so i can use it on both machines
10:53 PM Tom_L: every thing else is the same
10:53 PM rue_shop3: I use a db25 for the 4 motor and 4 limits
10:53 PM rue_shop3: and 0/5/12V power
10:53 PM rue_shop3: ...
10:54 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/rue/Control2.jpg
10:54 PM rue_shop3: 4*4 = 16, +4 = 20, +3 = 23
10:54 PM Tom_L: all the plugs on the side are the same for both
10:54 PM Tom_L: or will be
10:54 PM Tom_L: db25 is to the pc
10:54 PM * rue_shop3 nods
10:54 PM Tom_L: other db25 is to the pendan
10:54 PM Tom_L: t
10:55 PM Tom_L: the orange are limits
10:55 PM rue_shop3: and my spindle is just a switched recepticle
10:55 PM Tom_L: and i'm gonna change that plug
10:55 PM rue_shop3: atx?
10:55 PM Tom_L: itx
10:55 PM Tom_L: you can see it
10:55 PM rue_shop3: k
10:55 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Mill_Steel/Assembly/Z_Motor_Mount1.jpg
10:55 PM Tom_L: there
10:56 PM Tom_L: the screen is mounted to the wall
10:56 PM rue_shop3: nice shround on the back of the switch....
10:56 PM rue_shop3: hmmm
10:56 PM Tom_L: the box is sitting on the shelf
10:56 PM Tom_L: what switch?
10:56 PM rue_shop3: power switch on right of cabinet
10:56 PM rue_shop3: 120V
10:57 PM Tom_L: bent plastic
10:57 PM Tom_L: guess why?
10:57 PM rue_shop3: 120V
10:57 PM Tom_L: it nudged me a bit so i figured some plastic was in order
10:57 PM rue_shop3: yea
10:58 PM rue_shop3: heatshrink can be hit and miss on those, often the lugs take a 90 to rivets into the switch, and its not all shrouded by heatshrink
10:58 PM Tom_L: there are other non protected hot spots in it too
10:58 PM Tom_L: most of the bottom of the door is 120
10:59 PM rue_shop3: should prolyl pull those old relays out
11:00 PM Tom_L: the new ones are AB
11:00 PM Tom_L: allen bradley
11:00 PM rue_shop3: and the optos we did
11:00 PM Tom_L: the only cheap one left is just an inhibit signal
11:00 PM Tom_L: yeah
11:00 PM rue_shop3: I was kinda surprised that worked
11:00 PM Tom_L: one and a spare
11:00 PM Tom_L: pfft
11:00 PM rue_shop3: but iirc it worked for like 3 days at 1Hz and didn't fail
11:01 PM Tom_L: works great
11:01 PM rue_shop3: hmm, I'm in somekinda dazed useless state
11:01 PM Tom_L: i fixed a little bit of logic so when it swites the back emf doesn't slam it to a stop
11:01 PM rue_shop3: need to focus
11:01 PM rue_shop3: on... something
11:01 PM rue_shop3: ...
11:02 PM Tom_L: last couple days were a complete writeoff
11:02 PM Tom_L: i can't wait to get my parts back
11:02 PM rue_shop3: I dont have much family stuff going on
11:02 PM Tom_L: i still need to get the steel milled but i can mount stuff anyway
11:02 PM rue_shop3: so, I cant say I did much of that
11:02 PM Tom_L: tonight's was a bust
11:02 PM rue_shop3: me and ma made some stuff for her art things today
11:03 PM rue_shop3: you got a fair bit of family things that happen dont ya?
11:03 PM Tom_L: is it just you or other siblings?
11:03 PM rue_shop3: hah
11:03 PM rue_shop3: I'm alone in more ways than you think
11:03 PM Tom_L: heh
11:03 PM Tom_L: you get to do what you want
11:03 PM rue_shop3: just me
11:03 PM rue_shop3: and me
11:03 PM rue_shop3: and sometimes me too
11:03 PM Tom_L: i'm not lucky that way
11:04 PM rue_shop3: double edged
11:04 PM Tom_L: both can be
11:04 PM rue_shop3: yep
11:04 PM rue_shop3: k, well, the solder pot still works
11:04 PM Tom_L: it's more a balance this way
11:05 PM rue_shop3: 22 little tinned wires
11:06 PM Tom_L: i got drag chain coming tomorrow i think
11:06 PM rue_shop3: I thought you already had it?
11:06 PM Tom_L: not ready for it yet
11:06 PM Tom_L: ordered yes
11:06 PM rue_shop3: remember to back it properly
11:06 PM Tom_L: oh lay it on something?
11:06 PM Tom_L: yeah
11:07 PM Tom_L: i'll figure all that out as i go
11:07 PM rue_shop3: https://www.finelineautomation.com/products/cable-chain-1-meter-long
11:07 PM Tom_L: not exactly sure where it's all gonna fit
11:07 PM rue_shop3: armyofevilrobots, ^^^^ uh?
11:07 PM rue_shop3: armyofevilrobots, uuuuh... ..... is it?
11:07 PM Tom_L: that's kinda big
11:08 PM Tom_L: mine is 18 x 25 iirc
11:08 PM rue_shop3: I'd SWEAR its his machine...
11:08 PM Tom_L: should fit all the wires i think
11:08 PM rue_shop3: but, that wasn't my point
11:09 PM Tom_L: i just wonder about the bend radius on that stuff
11:09 PM rue_shop3: yea, there should be a tray under it
11:09 PM rue_shop3: for it to lay on
11:09 PM Tom_L: i figured as much
11:10 PM rue_shop3: armyofevilrobots, that has to be your machine, how many could be built *just* like that..
11:11 PM Tom_L: is that stuff pretty sturdy?
11:11 PM rue_shop3: https://www.simbal.net/wp-content/uploads/2015/10/PKK-1-430x320.jpg
11:11 PM Tom_L: seems to me it would flex alot
11:11 PM rue_shop3: can kinda see the tray under it
11:11 PM rue_shop3: its one-way-bend
11:11 PM rue_shop3: WHAT IS WRONG WITH MY BRAIN
11:12 PM rue_shop3: if I were drugged right now I wouldn't feel much different
11:12 PM Tom_L: i've got plenty of stuff to use under it
11:12 PM rue_shop3: surreal
11:12 PM Tom_L: i like that color, maybe i'll paint mine that color
11:12 PM Tom_L: oh, the legs on it too... that's what i was gonna do
11:13 PM Tom_L: and put screws in them to level it
11:15 PM Tom_L: i think i'm gonna come up with some better stepper mounts too
11:15 PM Tom_L: i'll have to think about that one
11:18 PM rue_mohr: ok, so
11:19 PM rue_mohr: on a scale from 1 to 10, for the quality of this lye based aluminum etching, I'd put it around _ZERO_
11:19 PM rue_mohr: all the resist came off, the bits in the etchant went away after about 2 hours?
11:20 PM rue_mohr: and there are pinholes in the rest
11:20 PM rue_mohr: and it got under the foils glue between the plastic
11:20 PM rue_mohr: so
11:21 PM rue_mohr: I might try something involving copper, aluminum, and salt water
11:26 PM rue_mohr: oh and ELECTRICITY
11:28 PM armyofevilrobots: @rue_shop3 That is a similar one to mine. Mine is a bit unique because I upsized it a bit, and it’s been modified over the years, but yeah, nearly the same.
11:29 PM rue_shop3: wow
11:29 PM rue_shop3: cool
11:30 PM rue_shop3: howd the day treat ya?
11:38 PM rue_mohr: Tom_L, how much was that ball screw?
11:39 PM rue_mohr: I'm not excited about the prices I see
11:42 PM rue_mohr: hmm, should I wake up or go to sleep
11:44 PM rue_mohr: https://www.aliexpress.com/item/SFU1605-ball-screw-length-300mm-Diameter-16mm-Step-5mm-end-machined-with-standard-BK-12-BF12/1835368168.html
11:45 PM rue_mohr: 16mm x 5mm pitch?
11:47 PM rue_mohr: yea ok, I think I get that
11:48 PM rue_mohr: so, thats prettymuch $75 right there
11:49 PM rue_mohr: so they do one side fixed and float the other side
11:49 PM rue_mohr: which is what I learned works years ago
11:50 PM rue_mohr: but it looks like they do the fixed side with two ball bearings...
11:50 PM rue_mohr: they do
11:51 PM rue_mohr: I used a ball and a thrust on mine
11:52 PM rue_mohr: Tom_L, at some point, see if you can work out what the lash is on that ballscrew, I'm curious
11:55 PM rue_mohr: there are a few prices that are workable
11:56 PM rue_mohr: why dont you use belt drive
11:57 PM rue_mohr: cause I'm worried about the belts steching
11:57 PM rue_mohr: use chain
11:57 PM rue_mohr: chain is lumpy
11:57 PM rue_mohr: I think your being overcritical
11:57 PM rue_mohr: I dont think, I know
11:57 PM rue_mohr: I dont think you know either
11:58 PM rue_mohr: go make a google cardboards
11:58 PM rue_mohr: how about one"/
11:58 PM rue_mohr: sure whatever or go to sleep
11:58 PM rue_mohr: sleep sounds good
11:58 PM rue_mohr: ok we should work on making a MT2 spindle
11:58 PM rue_mohr: ok, out of what?
11:58 PM rue_mohr: oh yea
11:58 PM rue_mohr: yea you forgot
11:58 PM rue_mohr: trip to sechelt?
11:58 PM rue_mohr: hmm
11:59 PM rue_mohr: if you came home with a driveshaft it wouldn't help, we cant cut it
11:59 PM rue_mohr: we could cast something
11:59 PM rue_mohr: mmmm
11:59 PM rue_mohr: lots of "stuff we need" blockages going on