MarkusBec is now known as MarkusBec_away
MarkusBec_away is now known as MarkusBec
MarkusBec is now known as MarkusBec_away
danimal_garage: after I saw your compressor, I can't convince myself to buy one retail
deals are out there
just have to be patient
what kind do you have?
5hp 80 gallon 2 stage 3 cyl
not at all
pretty quiet actually
i had a cheap little 20 gallon before this, and THAT was loud
time to go, my show is on
i see.. bigger doesnt mean louder
do stepper motor drivers usually leave the current going to the motor at all times, or only when it needs to turn? i'm making my own steper driver, but if i leave the motors "on" all the time, the amplifiers get rather hot
and if i leave it to switching, i'm worried about latency problem due to the sink current delay
DrMitch there seem to be 2 methods: leave it on, or have like a 'half current' setting which gets enabled on 'idle'
if you turn off the current, you lose position
but that also makes the holding-force much smaller so if you dont have encoders you could loose steps when not moved to a full step or so i guess
real drivers handle the steady state current limit by chopping
i may just get a bigger heat sink for the l298n's then
and leave it on all the time
our drivers have this 'lower the current on idle' feature.. they call it AMC .. but we have that disabled
are you running the L298 with a L297?
what's a few watts of power... right?
umm... i'm just doing L298 to amplify. and i'm controlling the stepping with a PIC mcu
we dont have central heating, so the milling room is always one of the nice ones
you're doing it wrong :-)
use a L297 and make a proper chopper
for the reason you've already found - it works badly otherwise
wait a minute, the L297 converts the step/dir signal from EMC into a stepper sequence?!
you need high voltage to get current into the motors fast. but if you have high voltage, you need current limiting, otherwise it will all melt
DrMitch: yes, and more
JESUS! I spent a whole afternoon programming this damn PIC!
the L297/L298 datasheets have a good 'reference implementation' schematic that shows you how to use the two chips together
well i may look into that. good thing it's going to take another week or so for the X and Y stages to ship to my place.
thanks for the info
So I was thinking, would a neural net be a good way to drive a mill, rather than PID
it could "learn" the mills intracisies then
IE theres a sticky bit 2/3d of the way down the X axis
prebias tables would be enough I think
1d tables could be in the motor driver itself
2d would be a bit more complicated, if it's only a certain combo of X&Y that sticks
but the 1d tables would both learn to peak the torque, so the 2d problem would be partially dealt with by 2x 1d solutions
they work for that specific problem
but thats what I like about the neural net, it works for most problems
my worry is all the errors it has to make, in order to learn :)
you'd have to let the mill play with lego for years before you trust it with power tools
bound it with a PID
IE make a PID that gets you within a mm or so, then let it go, IF it tries to push outside the bounds of the PID then drop back to the PID
ah build a retractable diamond lap into the slide and apply feedback through that :)
nn is not a bad idea for your counterbalance problem
fuzzy would also work
I'm wonding if NN might work as a general purpose thing
IE would it give emc abilities it doesn't have now
training is a bit of a problem
it could be partially trained in a simulator
and constrained when on the machine
well, for the lifting problem you could tune two pids, one for up and one for down
then train the nn to simulate both
I think the training should be fairly easy as well as you have a nice simple error
well if it boils down to a simple problem that a 1d or 2d table can deal with...
even 3d on a single axis, if speed, mass and accel are all params
yeah but you need to fill all that stuff out
and it depends on which way the error is
it gets quite complex quite fast
a phat pool of neurons with some outputs seems simple by comparison
the tool can do the work itself to get better ;->
heck you could even have a base net, then "train" it on specific jobs
you could have the net trained for job A with lots of weird cuts in it, or something perhaps
train the net to convert .3ds into metal at minimum cost
press the punishment button every time it spends money :)
looking to do that whole solid to Gcode thing now
it helps a lot if the solid is represented nicely first
converting a triangulated cylinder back into a drill hole is a nightmare
I'm having a go at doing sth like that in blender
all the blender devs are obsessed with 2.5 atm tho
biggest shake up in years. everything is broken again
do they have units in bender 2.5?
toast_ is now known as toastydeath
I don't think so
they really aren't moving in the CAD/CAM direction at all. I fear a fork may be needed
or I'll just finish my modeller instead :)
call it SolidHomes
work on heekscad
I'll look at opencascade first
survey starts at the foundations :)
MarkusBec_away is now known as MarkusBec
I just cant see how they can model anything without units
i mean anything inorganic is based on numbers
anyone on now?
nobody here but us chickens
wondering if the chickens here are smart enough ;)
i can count to 3 5 times out of 10
woot good enough!
any idea how to home A axis? its up to 800 degrees and will turn all the way to 0
way too long...
there was some discussion on the emc-users list about this recently
I think the consensus was it sucked lol
so no solutions to that eh
I'm rembering there may have been a solution
any log of that list?
but its probably not in a release
nfi where off the top of my head
where are you located anyway
[10:05:30] <Valen> http://sourceforge.net/mailarchive/forum.php?forum_name=emc-users
ohhh hows it going down uner
not too bad
i was in melbourne for around 5 years
findor: there's code for wrapped rotaries in emc2 master
not in any releases
I figured as much
was trying to find the thread
cant see it, I know it mentioned fanuc a whole bunch but thats probably not too helpfull
or how about there are 2 posts on it today
Re: [Emc-users] Wrapped rotary axes, Fanuc style: for testing
and the thread that spawned that was uestion qabout using a rotary table
sorry question about using a rotary table
there we go
[10:12:15] <Valen> http://sourceforge.net/mailarchive/message.php?msg_name=4AC3B759.5060104%40ntlworld.com
blender has numbers, just not units
the screw wizard assumes mm
fenn yeah I'm looking into opencascade now. it looks OK but C++
no C++ in blender, which is how I like it
i hate c++ too but the python bindings to opencascade aren't quite up to snuff yet
* fenn wasted a few months this summer on that
the grand final product: http://designfiles.org/lab/fenn/pngs/lego_snapping2.png
does it animate the fea? :)
oh yeah and my aggravated attempts to make a screw thread: http://designfiles.org/lab/fenn/pngs/occ_loft_bug.png http://designfiles.org/lab/fenn/pngs/thread_helix.png
the lego thing was about connectivity and defining interfaces which play nice with each other
so a pin goes in a hole for example
and you can run it on random for a while: http://designfiles.org/lab/fenn/pngs/lego_snapping4.png
if all mechanisms were reduced to a python class that worked in heeks & blender wrappers, that would rock
yeah well it turns out they do things sort of weirdly a lot in opencascade
a direct translation is not "pythonic" and you end up looking at the C++ documentation a lot
i got a lot of segfaults which i never figured out
anyway heekscad is the closest free software i've seen to actual solid modeling 3D cad
it's the file format that counts
STEP stores b-rep which says 'this is a trimmed cylindrical surface' but it's not CSG
yeah I like heekscad :)
Anyone know the value of the pot and how many turns it is? http://cgi.ebay.com/LM317-In-DC-or-AC-4V-30V-Out-DC-1-5V-27V-1A-Converter_W0QQitemZ390131133745QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item5ad5a0ad31
scroll down for big pic
I *think* I see 103 (10K)
103 is most likely
Number of turns?
not 25 ish ?
[11:45:19] <Jymmm> http://www.taydaelectronics.com/servlet/the-617/10K-OHM-TRIMMER-POTENTIOMETER/Detail
That's why I ask.
both look awfully close
25 turn is less common
in fact I dont remember ever using a 25 turn
ME neither, but this is ebay, straight from china too =)
I can't find the receipt for my spindull. time to take it apart
MarkusBec is now known as andi
andi is now known as andi___
andi___ is now known as MarkusBec
haha. only sign of heat damage is a dry joint on the mains input
[13:55:46] <MattyMatt> http://img692.imageshack.us/img692/5715/p1010046m.jpg
[13:56:48] <MattyMatt> http://img35.imageshack.us/img35/1934/p1010047fn.jpg
A few of the joints look crusty there
MattyMatt: i burned some of the coils of a similar one
I haven't even started milling with mine yet :)
by overloading it
that grinder in the pic is the tool I was using at the time
20 quid is cheap yeah, but to me it looks like a dimmer switch, 2 skate bearings and a small hoover motor :)
that's exactly what it is
the rubber ring around the top bearing suggests lack of structural confidence
but they're surprisingly good
36krpm is quite posh
it's not really balanced enough to run that high tho, tbh
I never go above 4
the one i broke was very well balanced
now i got an another one (for free) and it's not
IR had a dremel commutator fly apart at full revs one day
I thought they looked a bit thin :)
I can't tell if they're brass or bronze
probably brass. that's what the unburnt ends look like
bill20r3: did you see http://www.electronicsam.com/images/KandT/pcbmill/tableanddisp.JPG
part part and more parts
* bill20r3 looks
what is/was that?
no, to heavy-duty for a plotter.
it was a dispencing machine
a fraction collector?
like lab equipment?
na - we used it to put a clear coating over material
how's the precision, good enough for pcb's?
no - I am switching to leadscrews. (as it is - .015 per step)
can you switch out the motors to something geared low, and keep the cable-drive system?
then you could avoid the pain that is parallel-aligning the leadscrews
heh - I will probably run duel lead screws with a timing belt.. If I am really energetic - I might try a dual servo setup.
the cabling would have to be re-designed as it will not work as is on the new table
do you know what you're going to do for a spindle yet?
I don't know... I was thinking about getting a dremel but it sounds like they built pretty crappy.
I want something reletively light and cheap..
uhm, one sec.
I've started on one of these: http://mtm.cba.mit.edu/toolheads/spindle/makeit.html
it's light & cheap, although I don't know how good it'll be yet.
but I have some spare motors, if you need one.
heh - someone just posted that link earlier..
I just used drill rod, I suspect I'll be making another later using better parts.
I have heard that the Black & Decker RTS (I think?) is much better than the dremel, and cheaper too.
neat - I was hoping for something in the 30+rpm... I don't ask for much.
currently I'm using a Bosch Colt, it's not awful.
I was thinking about turning some pulleys to up the speed, and using 2 motors if I need more power.
I got like 5 motors in an ebay lot.
the Bosch is super loud at full speed, and my mill is in the house, other wise I'd just keep using that.
I have this: http://www.amazon.com/Bosch-PR20EVSK-1-Horsepower-Variable-Router/dp/B000ANQHTA
skunksworks: yes. I have one and it does seem pretty nice. I haven't used it enough to see if it lasts much longer than a dremel, but it does seem tighter.
I have a dremel that does pretty well, but I had to put foil around the bearings because they were loose in the housing.
The mounting on the B&D is the same thread as the dremel
It says 3 speed, but mine is really variable. There are just 3 detents on the knob, but you can put it in between to get variable speed and it will stay...
how loud is it at 30k rpm?
not too bad, I think about the same as my dremel or maybe a little quieter
for $25 at walmart it's hard to beat :)
yeah, that's cheap.
I haven't actually measured the runout on my dremel, maybe I'll do that tonight.
I measured the bosch at a hair under 0.004. (measured with a 1/4" to 1/8" bushing in, so that may not be helping)
I haven't either. I guess you mount it securely and use a dial indicator to measure runout?
yeah, I just put a dti in a vise, and turned the spindle by hand.
that is why we went to the rotozip style (sears brand) on the gantry - we started using a router - after reducing it down to 1/8 inch - it had almost .007 runout.
at that much - .029" carbide drills start breaking after a few holes.
[20:01:51] <alex_joni> http://failblog.org/2009/12/14/safety-product-fail-2/
alex_joni: I dont get it
Jymmm: seems a tiny bit overpriced
Eh if someone wants one for $40 and doesn't make it themselves out of pvc,bailing wire and duct tape...
alex_joni: always finds the cool stuff
latest machining video from over here: http://www.youtube.com/watch?v=RyFK235W-h0
it has a magic tool changer :)
what's with the generic rock music in so many machining videos? I'd rather hear the machine.
I feel that way about porn too
cradek: you would rather hear the MACHINE on pr0n ?
well I've already said too much.
* Jymmm can imagine cradek watching pr0n and you hear him saying "Oh yeah baby, work that tool changer... "
cool, my dad has an old RC sail boat
yes the ATC is indeed magical...
... and I think the rudder post is broken
Then cradek moaning... "Slap that E-Stop! harder baby, HARDER!"
wow that's a lot of coolant
Jymmm: you have a dirty mind
jmkasunich: Hey, it's all cradek, not me
* Jymmm returns to his R lesson
shiver me timbers matey
Keelhaul the swabs!
avast ye scurvy dogs
Get out o' me way, yeh landlubber
* archivist_attic rounds up the lazy lot and makes them walk the plank
and my spindle is finally ordered!
jmkasunich: didn't you have a simple formula for calculating shaft deflection? On something like this.. http://www.electronicsam.com/images/KandT/pcbmill/cablegantry.JPG
* frallzor is dreaming of his 2kW of happieness
^ shaft is aprox 25" long, travel is 18" .75" diam
[21:47:57] <jmkasunich> http://www.engineersedge.com/material_science/moment-inertia-gyration.htm
skunkworks, I'm impressed with my cheapo dremulike again now that I fixed it so easy :)
It's reassuring to know I can get a replacement in 20 minutes anytime the store is open too
hopefully this one will last until I can afford sth with a 1/4" collet too
my old metal cased B&D fits the bill in all ways except speed
1/8 is pretty much all I need if I mainly do circuit boards..
time will tell
and you get a nice set of usable tools, like a 2.5mm endmill and a similar ball mill
not quite enough to justify the whole purchase, but enough to soften the blow :)
I'd rather have 3 of these, than one a360 one
dammit gotta fix my %a3 key :)
guess what I did today MattyMatt! :P
When pressing mist and flood buttons in Touchy interface 800X600 mode the interface will expand and gooversize.
frallzor: ordered a good spindle? well with a mechmate it's a different story :)
pcb milling is my sort of ambition with this one
ordered the one suitabile for both drilling and milling
but I noticed they had a 2kW one of it too
so I had to get that one :P
you'll be glad of that when you're making tungsten turbines
not with a mechmate I wont :P
really? they look tough enough to me. it's all relative I suppose
arent turbines quite big? :P
ome are only 100mm diameter
cruise missile style
Im allmost regreting it all now :P
what? the whole mechmate?
the spindle :P
bloody thing cost more then I've spent on the mate so far
that was true for me too :)
2nd most expensive bits were the drawer slides
life can be a bitch
Its my personal christmasgift :P
I love myself and I wanted to show myself that I do this year :P
if it's any consolation, a body shop would charge even more to do a nice paint job
that im doing myself! :P
so you'll be ahead again then :)
think realistically what a finished machine is worth. it has to be e4000 minimum
probably much more if you had a professional reputation
yeah im saving alot of money =)
well I have quite a good one after building my old mill
so Im not a n00b now =)
But I could never sell the mate :P
it's big enough to make custom kitchens in. that's how I'd raise cash with one
I need a custom garage roof
when I built my first I visited a local carpenter for wood
he wanted a mill made for cabinetdoors and such
Guess I could sell stuff to him :P
see how much he'll pay for your 'mate. It might be worth starting again :)
but yeah a milling service would work :)
1.6x2.7m can do some stuff
a door or two
a team of 3 could be rich doing kitchens. one to make, one to fit and one to sell
or one to use as a bed since im going to bed now!
been playing with 2.4pre today, spindle syncronised movement seems better with low spindle encoder count :)
yup the fixes made the world of difference to my little Denford
Only thing I found is it can't remember what tool is loaded, keeps asking to load a tool that's already loaded on restart of file.
I went to work yesteday to teak program.. was running over 8.5 hrs. today in a 9.5 hr shift the 3rd part is ready to roll in the AM all the probing is done and that take near 1/2 hour
Ran 30 parts, only two tools used, tool 1, a cut grip for turning and parting off and tool 2 a threading tool. After parting off with tool1, and M30 rewind, on restart, Axis stops and asks to load tool1, gets tedious quickly! Works in 2.3.4 but not in 2.4
MarkusBec is now known as MarkusBec_away
anyone know if the current EMC can use NML to control instances running elsewhere on the network?
s/current EMC/current EMC UI/
that'd be nice, I've been using x11 forwarding with ssh, and it's kinda chunky
bill20r3: x11vnc is faster for most network
I'll give that a try.
I asked about it before and there were talk/suggestions about it... was hoping to find out if there is an update
not having multiple monitors to shield from chips would be a useful thing
Bed time GN