#robotics Logs
Nov 04 2017
#robotics Calendar
12:00 AM rue_shop3: I'm not sure how most people with bowden change the spool, I HAVE to splice the plastic
12:03 AM evilroot: Not if you do it right. The type I use you just depress a lever and you can pull the filament out of the tube or put it in easily
12:03 AM rue_shop3: you pull it back hot?
12:03 AM Tom_L: i've been using an orbital sander with 36 grit
12:03 AM Tom_L: works fairly good
12:03 AM evilroot: rue_shop3: yeah . . .
12:03 AM evilroot: Well not entirely by hand, I have the extruder at temp and use the panel to retract the filament
12:03 AM evilroot: Until it clears the J-head. Then press the lever and pull it out
12:03 AM rue_shop3: usually messes up on me
12:03 AM rue_shop3: maybe if it were just warm
12:03 AM evilroot: Then insert the new filament with the lever pressed, push it all the way to the head
12:03 AM evilroot: And then extrude until the old filament is out
12:03 AM evilroot: No different really than a direct feed
12:08 AM rue_shop3: on my direct machine I can cut and chain feed the next peice
12:09 AM rue_shop3: no rewind or splice
12:09 AM rue_shop3: BUT its 3mm
12:09 AM evilroot: Ah yeah, I use only 1.75 now
12:09 AM evilroot: Though one of my active machines still uses 3mm
12:09 AM rue_shop3: 1.75 prints better
12:10 AM evilroot: And two of the ones at hackerspace do
12:10 AM rue_shop3: I wasn't sold, but I cant deny it
12:10 AM evilroot: Yeah, hence why I use it exclusively now
12:10 AM evilroot: Better results
12:11 AM evilroot: I also think it gives the manufacturer less margin for error
12:11 AM rue_shop3: no the tolerance is still the same mm
12:11 AM rue_shop3: +-.02mm or something
12:11 AM evilroot: With 3mm I would always have to caliper to be sure . . . might be 2.85
12:11 AM rue_shop3: sot he % error on 3mm is better
12:12 AM evilroot: I don't mean tolerance thickness wise, I mean because it is a finer filament things like bubbles or impurities are easier to see
12:12 AM Tom_L: rue_shop3, you gonna fix up another mill?
12:14 AM Jak_o_Shadows: 4 slots cut, only 16 left
12:14 AM rue_shop3: I'm out of shop space
12:14 AM rue_shop3: I want to make another mill and reprap
12:14 AM rue_shop3: I have a box with "another reprap in it"
12:15 AM rue_shop3: I'm clearing up a room in the house to put some 8' relay racks in w/shelvs for printers
12:15 AM rue_shop3: I should be able to move these two to the house, "and have room for 2 more cnc machines"
12:15 AM i-make-robots: I have two prusa mk2s for sale. I'm looking to get the mk3. the mk2s are great, but I need the removable bed.
12:16 AM rue_shop3: of course, where the printers are now, I cant put cnc machines, but thats not the point?
12:16 AM rue_shop3: i-make-robots, we did removable beds for our i2's but then realized that interbed calibration would be a nightmare
12:16 AM rue_shop3: so we only use the first one we made
12:18 AM evilroot: Removable bed? Why?
12:21 AM rue_shop3: quick change
12:24 AM evilroot: Again, why?
12:25 AM evilroot: I mean build surfaces wear out, but only after months
12:25 AM evilroot: After 10 minutes of cooling parts just pop off
12:26 AM rue_shop3: depends
12:26 AM rue_shop3: I tear the tape alot
12:26 AM evilroot: Oh, non heated bed?
12:27 AM rue_shop3: WTF, why is my nose bleeding
12:33 AM evilroot: O.o
12:33 AM evilroot: You okay?
12:36 AM rue_mohr: dunno what happened, its not activly bleeding...
12:37 AM rue_mohr: maybe betwen the cold and the viri going around it got upset, just right side...
12:37 AM rue_mohr: I'd shove the micro camera up there, but I'd prolly just give it a good reason to bleed more :)
12:41 AM rue_shop3: when I blow my nose, thats not how I like to know its blown
12:47 AM Jak_o_Shadows: 8 slots left
12:47 AM Jak_o_Shadows: (i took sa break)
12:49 AM Jak_o_Shadows: SpeedEvil, you suggested the screwdriver? works great after i use the saw
12:49 AM SpeedEvil: yay
01:23 AM Jak_o_Shadows: arg stupid imperial rubbish
01:41 AM rue_shop3: shall we write and release a virus that finds any and all imperial numbers and rewrites them to metric?
01:43 AM rue_shop3: I went thru the whole pile, I cant find any of the todo lists
01:59 AM Jak_o_Shadows: TBH, i'd settle for having a better stock of metric stuff.
01:59 AM Jak_o_Shadows: I only have up to m4x30 in m4
01:59 AM Jak_o_Shadows: Need like, 60-70
02:00 AM Jak_o_Shadows: http://pasteall.org/pic/show.php?id=120038 is it so far.
02:00 AM Jak_o_Shadows: Going to need to put some more bolts in the middle.
02:02 AM rue_shop3: ... rov conroller?
02:03 AM rue_shop3: you need a good set of working pens
02:03 AM rue_shop3: and the manufacturing community seems to say that if you need screws longer than 10mm, you designed it wrong
02:03 AM rue_shop3: which was a surprise to me
02:04 AM Jak_o_Shadows: Christmas lights controller :D
02:04 AM Jak_o_Shadows: I have some nice pens - I don't use them enough, so I tend to scribble.
02:04 AM rue_shop3: ... how many are you controling?!
02:04 AM Jak_o_Shadows: They're probably not wrong. This would suck if you had any force on it
02:05 AM Jak_o_Shadows: I can control 19 channels. So about 10 sets?
02:06 AM Jak_o_Shadows: On the other hand, that pca9685 only has 16 channels. So I might stick to 16 for now.
02:06 AM Jak_o_Shadows: I only have 10 of the green "input" screw terminals
02:07 AM Jak_o_Shadows: Through, like, now that you mention it, it'd be plenty of channels, and just enough power for a small ROV
02:22 AM i-make-robots: story time! yesterday I put 12v5a into a 5v3a LED strip. somehow I did NOT kill it.
02:22 AM i-make-robots: i thought I had, but the next day i tried to demo the damage and it worked fine. funny old world, hey?
02:23 AM i-make-robots: specifically, these: https://www.instagram.com/p/BbDBvRYg4Lp/?taken-by=imakerobots
02:30 AM Jak_o_Shadows: the individually addressable ones?
02:37 AM i-make-robots: yes
02:37 AM i-make-robots: ws2811
11:49 AM rue_bed: anyone know a code mapping tool that will tell you what fn's call which?
11:59 AM rue_bed: adlint and ncc
12:00 PM rue_bed: cflow
12:10 PM Tom_L: straight brace cut but not finished
12:10 PM rue_mohr: upearly
12:11 PM Tom_L: 2nd time today
12:11 PM Tom_L: 4 was the first one
12:11 PM Tom_L: then 7
12:11 PM rue_mohr: hmm
12:11 PM Tom_L: calculated i didn't cut enough material for the angle brace
12:12 PM Tom_L: flipped back to back i need 7.375" and have 7 ish
12:12 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Mill_base_XAxis3.jpg
12:12 PM Tom_L: brace bracket on the right end
12:12 PM rue_mohr: you can weld-build .375
12:12 PM Tom_L: not how i roll
12:13 PM Tom_L: i could redesign it shorter though
12:13 PM Tom_L: i don't need all that adjustment
12:13 PM rue_mohr: do you see how mass-manufacturing methods are not always efficient for producing one-offs?
12:14 PM Tom_L: i make it work
12:14 PM Tom_L: cut all the 6" pieces then the 2ish ones
12:14 PM Tom_L: with a stop on the saw
12:14 PM Tom_L: will make these braces 2 at a time
12:14 PM Tom_L: clamped together
12:15 PM Tom_L: the flat sawed rather well with the jigsaw
12:16 PM * rue_mohr nods
12:16 PM * rue_mohr tires not to nod off to sleep
12:17 PM rue_mohr: it got COLD
12:17 PM rue_mohr: I swear in a week it went from 10c to -1.5c
12:18 PM Tom_L: i just wish i had one of those belt sanders with the flat round disk on it
12:18 PM rue_mohr: hah
12:18 PM Tom_L: on a stand
12:18 PM rue_mohr: I made a disc sander, I was just given a little belt sander
12:18 PM Tom_L: i have a belt sander
12:18 PM Tom_L: i need to get some more belts
12:18 PM rue_mohr: heh
12:18 PM Tom_L: wonder how long the HF ones would last
12:19 PM Tom_L: maybe a couple turns around the belt?
12:19 PM rue_mohr: their just emery cloth thats been taped with that reincorced tape
12:19 PM Tom_L: i got boxes and boxes of all kinds of 3m paper for disk sanders
12:19 PM Tom_L: free
12:19 PM rue_mohr: figures
12:19 PM rue_mohr: you and evilroot
12:19 PM Tom_L: my friend made a machine for 3m to cut them out
12:19 PM Tom_L: they gave him all sorts of stock to test
12:20 PM rue_mohr: smack in the middle of manufacturing central
12:20 PM Tom_L: i've got alot of it
12:20 PM Tom_L: unfortunately he died probably 6-10 yrs ago
12:20 PM Tom_L: good way to go though. in his sleep
12:21 PM rue_mohr: I'd like to go on an artificial platform about 8000 years from now
12:21 PM Tom_L: his company builds presses to cut decals etc for road signs etc
12:21 PM rue_mohr: cool
12:21 PM Tom_L: remember the firebird on the hood of the old firebirds?
12:21 PM rue_mohr: k
12:21 PM Tom_L: his machines cut those out
12:21 PM rue_mohr: cool
12:21 PM rue_mohr: EDM?
12:22 PM Tom_L: stamp i think
12:22 PM rue_mohr: or just presure
12:22 PM rue_mohr: wow
12:22 PM Tom_L: like a big cookie cutter
12:22 PM Tom_L: they'd ship a huge block of steel out of town to have it ground very very flat
12:22 PM Tom_L: like 4" thick
12:22 PM Tom_L: huge
12:22 PM rue_mohr: :/ I had a dream that told me I have no idea of how to get from where I am to where I want to be
12:22 PM Tom_L: 4 x 8 etc
12:23 PM Tom_L: nobody knows that
12:23 PM Tom_L: it's an adventure
12:23 PM Tom_L: you veer to the left, you just autocorrect
12:23 PM rue_mohr: it left me with a bit of a sense of futility
12:24 PM Tom_L: you're not supposed to think about that stuff
12:24 PM rue_mohr: I been looking at the shop and this spare livingroom trying to work out how to use the space
12:24 PM Tom_L: called a reality check
12:24 PM rue_mohr: I'm having a hard time getting my perspective
12:24 PM Tom_L: i re'adjust
12:25 PM Tom_L: find simpler projects etc
12:25 PM rue_mohr: I really need to rework priorities
12:25 PM rue_mohr: I have 80% of the things I need, in the worst arrangement possable
12:25 PM Tom_L: don't climb the mountain until you're past the foothills
12:26 PM rue_mohr: its like having a flatbed truck, but carrying materials cause your not sure how to best use the truck
12:26 PM Tom_L: anyway, i'm 2 cuts less than what i had last night
12:27 PM rue_mohr: (the words 'for material deliviery" are supposed to be in there)
12:34 PM rue_mohr: I suppose analyzing workflow would be a good start
12:34 PM rue_mohr: ok, done, workflow is random
12:35 PM rue_mohr: material might come from anywhere, may or may not get rough cut, may or may not get machined
12:35 PM rue_mohr: so, it sounds like a I need a star topology
12:37 PM rue_mohr: right now I have areas defined as: programming/cad mechanical, and electronics
12:37 PM rue_mohr: (and parts-storage project-storage)
12:38 PM rue_mohr: the actual electronics workspace is about 1/4 of whats allocated for it
12:38 PM rue_mohr: the mechanical workspace is about 200% of whats allocated for it
12:38 PM rue_mohr: which steps on the programming and electronics spaces
12:39 PM rue_mohr: project storage takes up 150% of the space allocated for it
12:39 PM rue_mohr: calc 0.25*2*1.5
12:39 PM rue_mohr: 0.25*2*1.5 -->> 0.75
12:40 PM rue_mohr: this seems to indicate that if I re-partition the shop, there is enough space
12:40 PM rue_mohr: if I'm only using 75% of my shop, whats taking up the other 75%?
12:41 PM rue_mohr: thats one of the big questions
12:42 PM rue_mohr: and how do I implement a star topology workflow?
12:45 PM theBear: you gonna fill it with zero's a few times ? you know, for security reasons :-)
12:51 PM i-make-robots: are there more efficient ways to store these things?
12:51 PM i-make-robots: library sciences to the rescue!
12:51 PM i-make-robots: maybe have a garage sale and get rid of the stuff you rarely use?
12:52 PM SpeedEvil: rue_shop3: easiest way to compact the volume you need to store things - get a hydraulic press
12:52 PM i-make-robots: when i put a project to bed, i put the year on the box. a project more than five years old? document it, then sell the parts.
12:53 PM i-make-robots: i've got a 2010, 2011, and a 2012 that can all go.
01:12 PM rue_mohr: rounding a little, nobody even knows what the valuable stuff I have IS, no less wants it, the things I'm not using are NOT gonna sell in a garage sale
01:12 PM rue_mohr: mechanical needs more space
01:12 PM rue_mohr: so, where is it going to come from
01:13 PM SpeedEvil: rue_shop3: tunnel boring machine.
01:18 PM rue_mohr: large underground caverns dont require building permits?
01:19 PM rue_mohr: subterranian space dosn't count as square footage, so the 100 square foot building that is the top of the elevator shaft is fine at 100 square feet?
01:19 PM rue_mohr: (100 square feet and under dont require a building permit)
01:22 PM SpeedEvil: Just dig far enough down to get an army of mole people.
03:45 PM i-make-robots: "garage sale" on ebay.
03:46 PM i-make-robots: having now written simulators for 4 different robot arms, I'm trying to make a generic PTTPTP arm class that can be customized for each arm type. tricky!
06:23 PM i-make-robots: i have a question about external stepper drivers. if you're able to help, please respond.
06:24 PM malcom2073: Sure.
06:30 PM Tom_shop: http://wiki.linuxcnc.org/cgi-bin/wiki.pl?Stepper_Motor_Speed_Limitations
06:31 PM i-make-robots: i'm only trying to get some movement at all.
06:31 PM i-make-robots: i've got a Ramps board connected to an external driver. i'm testing current at the driver where the control pins connect.
06:31 PM Tom_shop: http://wiki.linuxcnc.org/cgi-bin/wiki.pl?Stepper_Drive_Timing
06:31 PM i-make-robots: i'm getting nothing on the pulse pin. solder looks ok, wire seems ok. not sure what I've missed.
06:32 PM i-make-robots: pin in the software is good.
06:32 PM Tom_shop: enable selected?
06:32 PM Tom_shop: often a gotcha
06:32 PM i-make-robots: enable power is HIGH, which has achieved motion on two of the six drivers.
06:33 PM i-make-robots: i have a mix of nema23, nema17, nema14, and nema8. both nema17 are moving.
06:33 PM i-make-robots: the others do not respond.
06:33 PM i-make-robots: max current per channel has been checked.
06:33 PM i-make-robots: steps per turn set to the same for all drivers (1600)
06:33 PM i-make-robots: i should mention the nema23s are on larger drivers than the rest, but all are the same manufacturer.
06:34 PM Tom_shop: wired ok?
06:35 PM Tom_shop: get any hum or hard to turn?
06:35 PM i-make-robots: i have a 2500us high and another 2500 low on the pulse pin, now i see 2.5v on the multimeter.
06:36 PM malcom2073: i-make-robots: If some of them run and some don't, swap drivers or motors around,see if you can isolate the problem.
06:36 PM i-make-robots: i *think* it's wired ok, but I've read the documents three times now and it seems to match.
06:36 PM malcom2073: If any of the motors have been disconnected *while powered*, that will fry the drives
06:36 PM i-make-robots: https://www.omc-stepperonline.com/geared-stepper-motor/nema-23-stepper-motor-bipolar-l76mm-w-gear-raio-471-planetary-gearbox-23hs30-2804s-pg47.html?search=23HS30-2804S-PG47
06:37 PM Tom_shop: try an ohm meter on the leads for matched pairs
06:37 PM Tom_shop: unhooked from the driver of course
06:37 PM i-make-robots: https://www.omc-stepperonline.com/download/DM542T.pdf
06:37 PM Tom_shop: 4 6 8 wire?
06:37 PM i-make-robots: all 4 wire
06:37 PM Tom_shop: that's just too easy
06:38 PM i-make-robots: wierd that i have to put high on enable, when the papers say put low to enable.
06:40 PM i-make-robots: wierder still, the steppers don't even warm up
06:45 PM i-make-robots: ah, there we go!
06:46 PM i-make-robots: the slop in the gearbox was hiding the movement.
06:48 PM i-make-robots: can you please confirm for me: on the https://www.omc-stepperonline.com/download/DM320T.pdf, is the "opto" pin supposed to go to ground if the step, enable, and direction pins are being driven from the controller?
06:48 PM i-make-robots: page 6 has the schematic
06:51 PM malcom2073: i-make-robots: Yep, ensure opto is tied to VCC
06:51 PM i-make-robots: I have tied to gnd.
06:51 PM i-make-robots: because i have positive voltage from the other three pins.
06:51 PM malcom2073: That's not what the datasheet says to do
06:52 PM malcom2073: It says tie opto to VCC, and pull step, enable, and direction to ground.
06:52 PM * Tom_shop seconds that
06:52 PM i-make-robots: damnit.
06:53 PM i-make-robots: I don't have a nice way to get 5v to that pin.
06:53 PM i-make-robots: thank you :)
06:53 PM malcom2073: Np. You can use 12v there, if you add current limit resistors to your three lines
06:55 PM malcom2073: Looks like they use a 270ohm resistor for 5v, which means they're expecting 18.5mA. To get that with 12v, you need a 378ohm resistor on your step, direction, and enable lines
06:55 PM malcom2073: Tom_shop: Double check my math on that?
06:57 PM Tom_shop: busy makin sparks fly in the shop...
06:58 PM malcom2073: Heh
07:00 PM Tom_shop: tryin to get all this metal cut out
07:12 PM i-make-robots: hm. so i put 5v to opto and GND to ena, made the others arduino INPUT and then modulated them as normal. no motion.
07:13 PM i-make-robots: the two larger drivers are working now, so it's just these smaller ones that I haven't puzzled out.
07:14 PM malcom2073: You want them to be outputs
07:14 PM malcom2073: not inputs
07:14 PM i-make-robots: when i test from ena to gnd i get 1v.
07:14 PM malcom2073: input may be too high of impedance for it to work
07:15 PM i-make-robots: doesn't seem to make a difference.
07:16 PM i-make-robots: if positive is coming from vcc to opto and supposed to leave through the pul/ste/ena pins, then those three pins at arduino should be input to sink the current, right?
07:16 PM i-make-robots: digitalWrite high to block the current, iirc.
07:17 PM malcom2073: Incorrect
07:17 PM malcom2073: input does not sink, it's for sensing
07:17 PM malcom2073: output sinks and sources
07:17 PM i-make-robots: ok, then back to my "it don't seem to make a difference."
07:17 PM malcom2073: Input is for digitalRead
07:17 PM malcom2073: Hmm
07:18 PM i-make-robots: i've used digitalwrite on an input to act as a resistor before.
07:18 PM i-make-robots: mostly with multiplexing LEDs.
07:18 PM malcom2073: digitalWrite on an input iirc sets weather it's a pullup or pulldown, lemme look
07:18 PM malcom2073: It enables or disables the internal pullup
07:19 PM malcom2073: Which can in some situations, be used to switch things on and off, but most of the time it will be undesired results unless you know what is going on
07:23 PM i-make-robots: ok. so they're all set to output. i have 5v on opto, gnd to ena, 5v to dir, and i'm toggling ste every 2500us. no movement.
07:24 PM i-make-robots: i have motors 0 and 1 (big) moving, and 2-5 not moving. *sigh*
07:25 PM i-make-robots: time to go get food.
07:25 PM i-make-robots: thank you for your help.
07:25 PM malcom2073: That's... odd.
07:25 PM malcom2073: Yeah sorry
07:25 PM i-make-robots: agreed
07:25 PM i-make-robots: also these motors advertise 1 deg of slop and that's a fucking lie. it's at least +/-5
07:27 PM malcom2073: Ouch
07:35 PM i-make-robots: it's probably me somehow. maybe a gap between the stepper key and the shaft.
08:09 PM justanotheruser is now known as xustanotheruser
09:59 PM * Tom_L pokes rue_shop3
09:59 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Mill_Steel/Steel6.jpg
09:59 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Mill_Steel/Steel7.jpg
09:59 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Mill_Steel/Steel8.jpg
10:00 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Mill_Steel/Steel9.jpg
10:00 PM Tom_L: http://tom-itx.no-ip.biz:81/~webpage/cnc/Mill_Steel/Steel10.jpg