roltek: what lines do you mean?
desription is a thread going from z.1 to z-1.0
I guess that's a problem with synergy then?
hm, maybe G32 is Fanuc stuff DIN66025 doesn't know it, the Siemens 840D controller also
that's a problem for anybody that your telling them that this is a good program
roltek: who's telling that?
g33 is also not in hass
the 2 most used control's in the us are fanuc and hass
is that hass or haas?
sieman's has very little market share in us
hm where can i find the aktual ISO standard, i think we have to look there, because every controller has its own standards
Imperator_: there are things that aren't defined in the iso standard
did seiman's make iso standard for cnc control's
and that's the reason this is not standard
roltek: he means the rs274
it's EIA not ISO, but close
i don't know where you can find standards
you can buy them
it is completely up to you what you make emc standards
roltek: right now we're trying to gather data of what others do
and try to get with the flow
logical thinking is if a hobbist uses emc and decidese to open a shop his next machine will be a haas
now he will note be able to use his programs he used before
the g code will have changed
if he is in the US ... In Europe he buys a Gildemeister with Siemens controller, in russia .... china
in the us we don't use seimens
the us is only part of the world
i have used siemen's on cnc gear cutting controls
imagine US 600 years ago ;)
in machine tools germany is leading that is the reason why Siemens often makes the standards there
was emc started at nist or china
no HAAS, no Fanuc ;)
started at nist developed in the world
* fenn pokes alex.. what do they use in romania
fenn : different stuff
seen them all, can't say which are more common though
rs274 really doesn't define any lathe codes.?
we should call up some tiny controller manufacturer and see what they do
"alo, is this okuma? yeah what code do you guys use for threading?"
they have both g32 and g33
i am not sure but is g33 for a varible lead thread where you are side cutting
Threadcutting, constant lead
34 & 35 are variable lead..
maybe we should mail petro @ machinetoolhelp.com
* fenn yawns
maybe I should go to bed
see you later i am out of here too
the other question is what is RS274
Imperator_: the g-code standard
but there are at least 4 versions of it
I think -D is the last one?
might be wrong though
here in germany it is DIN/ISO 66025
i never heard something about RS274 only at the EMC project everybody speeks about
[00:33:04] <alex_joni> http://en.wikipedia.org/wiki/G-code
cradek: that link I just pasted, has a nice lathe example :D
hmm it says g33 for fanuc threading
wikipedia doesn't lie
that's almost like google lying.. not gonna happen/be accepted
well i wouldn't bet my life on it
so is g96 always ft/min or is it also m/min
depending on G21/G20
[00:36:41] <alex_joni> http://en.wikipedia.org/wiki/G-code
Imperator_: you missed that
Imperator_: "RS274 is a programming language for numerically controlled (NC) machine tools, which has been used for many years. The most recent standard version of RS274 is RS274-D, which was completed in 1979. It is described in the document "EIA Standard EIA-274-D" by the Electronic Industries Association [EIA]."
is that the right association ?? What about ISO
in germany everything was DIN Deutsche Industrie Norm = German industry standard, now everything is ISO
ANSI is the big standards corporation
and ANSI supervises both EIA and ISO
but EIA is for some industrial stuff, including g-code
uff 2:40 am
in romania it is 3:40 right ?
3:45 right now
EIA RS 274 B 1968
EIA RS 274 C 1978
EIA RS 274 D 1980
i think EIA is involved because rs-274 was used to draw circuit board traces with photoplotting machines
no wonder it's so absurd - it's 25 years old
version A is 50 years old
so that means the original was around before computers were invented
our k&t which was designed in the 60's with a ge controller has most of the same commands as todays controllers. It would only conture radiuses of 9.9999 inches though ;)
you needed leading zeros though - it didn't see decimal points
found something DIN66025 = ISO/DIS6983 Numerical control of machines -- Program format and definition of address words
hmm i was wrong, the Z1 computer was invented in 1936 :P
amazing.. it has a floating point processor
[00:53:10] <Imperator_> http://webstore.ansi.org/ansidocstore/product.asp?sku=ISO+6983-1%3A1982
i think the right one is ISO 6983
and it should maybe identical with RS274D
cradek_ is now known as cradek
Same shit, different day
i got it
you ever seen a pic of the v22 osprey tilt -a-rotar airplane??
i've seen a pic of the gear that turns the propeller - it had a huge chunk missing and they stuck it in anyway!
i work with the guy who made the machine to grind that gear
helical face gear technology
we just won the contract to mfg the re-designed nose gear
it will lift a 10 000 lb payload and carry it 100 miles
i was reading an article about how they crash a lot
at 250 knots
because that gear failed :)
they lost 2 in a row in 2000
was the drive shaft arrangement i heard
there was a major redesign as they were grounded
since 2004 they have had raves
want a news letter??
Tilt-rotor Sheds Troubled Past
Osprey could be ready to deploy by 2007
the latest screw up was a lack of de-icing capability...
indeed it is.
* alex_joni opens his eyes slowly
ewww.. all that light :(
alex_joni, beware the evil day-star
robin__: how's it?
g'day mr giacus
* fenn salutes
howdy fenn, ain't it a bit late there?
or is it early ?
its late i need to go to beeeeed
please explain to DanF_DrC why usb is such a bad idea
is there any hardware recomendations for emc2?
where's DanF_DrC ?
ValarQ: what hardware? PC? or cards?
there ought to be a wiki page for that
i can never remember which is the "good" one and which is the "bad" one
fenn: what do you mean?
people kept asking that at cnc-workshop and i was like.. uhhh they all work i guess
there are no really bad ones
"which computer should i use to run emc"
apparently some intels are really high latency
the problem is that people tend to think that modern computers 2GHz will work twice as fast as older 1GHz machines
and that's not true
the older the CPU, the better the latency relative to that CPU frequency
so probably a 386-DX-40 behaves the most predictable for RT stuff (lots better than a 2GHz P4)
the problem is that you want speed too ;), so the DX40 gets ruled out
so the overall problem is finding a balanced middle ground
somewhere around 400-2000 MHz should be OK under any circumstances
why do you need such processing power? isnt most of the latency from the isa bus?
* fenn wants numbers dammit
isn't base_period quite dependent on the cpu clock?
fenn: right, if you talk about parport stepping & such
ValarQ, fenn: you are both right
jmk mentioned you could get gprof-ish numbers if he turned some kernel timer back on
i think that was the one that broke stuff
fenn: gprof ?
gprof tells you how many times a particular function gets called and how long it takes to execute etc etc
fenn: I am running 5.9 usec BASE_THREAD on my Athlon XP 1600+
the reason i ask is that i'm having some problem with "joint error":s again
fenn: right, but on some kernel&RTAI combinations turning that on will make it run 20-times slower (or even slower)
ValarQ: what setup? what emc2?
i had to tweak the base_period setting
ValarQ: what value are you running now?
and again, what emc?
BASE_PERIOD = 0.000250
ok, what hardware? and what distro ?
ValarQ: that's INSANELY high
x86 P3 600MHz debian
you should be running 0.000025
i do know it is high
but 0.000050 (the default) should work ok for you
why did you turn it up?
i had problems with my system locking
maybe i was to fast tweaking the wrong setting?
oh, and btw. the latest CVS doesn't use 0.000050 but 50000 nsec instead
whats the point of that?
#+ Base task period, in nanosecs - this is the fastest thread in the machine
BASE_PERIOD = 50000
fenn: removing insmod motmod from the emc runscript
now loadrt motmod from the hal file
ValarQ: a few days
hal still cant do simple multiplication?
* fenn grumbles
do it, don't grumble
i dont know where to begin
alex_joni: ok, i haven't updated it in a couple of days...
ValarQ: it would be best for you if you checkout the TESTING tag
that's the latest proven version
and that tag gets moved when we think it's ok to move it
HEAD might be broken once in a while
i'd have to extend the "hal description language" i guess
fenn: right, it's not that trivial
ValarQ: co -rTESTING emc2
is the developer cvs down?
ValarQ: yes :(
and now it's the weekend, and SF doesn't give a damn
* alex_joni hates that
problematic when using cvs
and the biggest problem, this is not the first time it happens
ValarQ: use anon checkout, that works
well, i can't reach the machine on a week anyway...
ValarQ: bottom line, the 650MHz machine should be plenty
err.. 600 ;)
ok, i won't buy a new supercomputer just for emc2 in a while then :)
ValarQ: have a user running a 300MHzish PC with 64MB ram, emc2+AXIS
says it works great
but he's running puppy installed, so a lightweight distro
anyone know anyone that have bought this? http://www.team-haase.de/pages/2000_beschreibung.html
a semi pro table top mill for 2k$
fenn said you want to talk about USB ;)
I just figured the neatest for PC robotics would be a controller with USB interface. he didn't agree but didn't know why : )
* fenn would like to know too
a controller with USB interface might work
but the controller needs to do the actual control stuff
PID & step-outputs & such
lets use a hexapod as our example
such a controller already exists: the G-Rex
for a CNC mill I would definitely go with waypoint functionality in a controller so there would be no realtime demands on the pc
DanF_DrC: why so?
fenn: you'd need an external controller that does kins, not likely you'll find one
so it could handle acceleration etc etc
if i had a self contained external controller i'd use ethernet
DanF_DrC: emc2 on a PC does that perfectly
there's even RT ethernet
fenn: ethernet or USB .. same sh*t really ;)
alex_joni, also when the pc hangs for a split second?
DanF_DrC: RT-Linux doesn't hang
RT being RTLinux or RTAI
if you're talking M$ stuff, then all bets are off (I mean software only solution)
a turned off computer doesn't hang either. I would prefer a platform where actual software exists too
DanF_DrC: then how can we help you? this is the #emc channel afterall
can you explain why USB is so bad
fenn: USB is good for most applications, RT control it's not
fenn: you have about 1msec packet rate
so you can only send data every 1msec, even if you send huge packets, that won't help you for your application
got link for the grex? all products in the world seems to have that name
[11:03:13] <alex_joni> http://www.geckodrive.com/
G-rex is the link i showed you earlier
note: not affiliated in any way
G-101 and G-100
ah yeah. the one with no specs on it
anyone know the specs?
DanF_DrC: there is a group at groups.yahoo.com
you can ask in there
the specs are on the website I just pasted
would you agree that there is something wrong when one has to do that?
6-axis step and direction outputs
6 quadrature encoder inputs
16 general purpose outputs
22 general purpose inputs
4 analog outpus
4 analog inputs
USB and Ethernet
ok so the two are the same except for casing?
the G101 is inside the G100
woudln't that just be crazy if they had this info on their site :)
it would be nice
I reckon their website isn't the best one I've seen
at least it isn't offensive
it's clear but grossly lacking
DanF_DrC: another option might be to use a PC-based CNC software (like emc) with external Hardware generated pulses
all the info on the yahoo group should be on the website imho
is the grex pc direct?
does the pc pulse with the grex
he means does it send g-code or step/dir
from the PC to the g-rex you send g-code
the g-rex then generates the HW pulses and sends them to the drives
not sure it's really g-code you send, but high level movement commands anyways
ok highlevel. does it support acceleration?
it has settings for that
but then again, have you EVER seen a software/hardware that doesn't handle acceleration?
* alex_joni hasn't
not bad. what's max steprate? and does it have 8th microstepping
the microstepping is in the drive, not in the control
max steprate is around 1MHz I think
but as they say.. RTFM
g-rex just gives you 5V logic signals
alex_joni, I've seen pro controllers that didn't do accel right
er, well that's not quite right
DanF_DrC: if you want a semi-cheap solution (a good one), I would recommend: http://pico-systems.com/univstep.html
you probably don't know this but does it have proportional acceleration?
that's a hardware step generator, commanded from emc
no idea about g-rex internals, only what is on their site, never tried it really
ok fair enough
DanF_DrC: if you want a good machine, then you need servos
about 1-2k $ / axis
at that price I would by a finished machine instead
a toy maybe
a real CNC machine is about 50-60k plus
if you want to mill ships sure :)
but then again, it depends on what you expect
* alex_joni has seen, touched 1M+ machines
so 1-2k/axis is cheap for those
you can always go more expensive. I can find a cool video clip from one later but let's stay within reason :)
DanF_DrC: what do you want to do?
with the GREX, what motors? any outthere with encoders and not super overpriced?
if you want encoders, then the best solution might be the G340 from geck (that's a servo drive with step/dir input, DC motors & encoder feedback)
it doesn't work to use encoders on steppers
hehe then what's the idea with the grex?
what do you mean?
doesn't it support encoders?
it seems to, not sure how it handles them though
carefully I would hope
maybe only as position feedback, to ferror if something is wrong
that would be an obvious use for them :)
on servos you have a PID loop to control velocity based on feedback
DanF_DrC: it's not at all obvious
and I'm all for that if only they weren't galactically stupidly overpriced
encoders usually are used on servos for feedback, so you know where you are, how fast you went, etc
a decent encoder is about 1-200$
oh no!!! not step/dir servos!!!!!!!!
also a crime
wouldn't say that is overpriced
fenn: why not?
it's a disc with a light on it
DanF_DrC: the next time you open one, we'll talk again
1$ is a crime
DanF_DrC: then build yours and stop whining
I am but one man and unable to correct the mistakes of the world
doesn't make them right tho
DanF_DrC: whining doesn't help either
* alex_joni uses resolvers at work
a motor is about 3000$ (AC motor)
and I really won't buy a cheaper one
hehe of course not. why would you
that's without the drive and power supply
and you say that like it was a good thing
* fenn doesnt think so
sometimes it's better to buy good stuff
you will excuse me if I fail to see the greatness of a simple electromotor priced like a car
i have $3000 servos that i paid $40 for
servos are high precision stuff. the only what you can do is buying a used one at ebay. they have usualy damaged magnets, but good enough for hobby users
it's possible to do good without overpriced
fenn: lucky you, can you buy that in 300+ quantities?
and you all think it's reasonable pricing
or get one in 12-24h if it fails?
have to pay full price for rush service
that's why i got 7 of them
all I'm saying is there are users and users
maybe you could stock one if it cost 100$ instead
some are looking for moderated quality low cost,
do you have a link for this device?
others are looking at high quality, moderated cost
no, it was "the great servo gold rush of 2006"
DanF_DrC: which one do you mean?
no longer there
the 3000$ ac motor
fenn: then you're set ;)
fenn: otoh, I sell quite a few robots/year, and I have lots of motor types & drives, I even have most of them on stock (1-2 pcs quantity)
but this is industrial stuff, can't mess around
how much is a brand new robot?
alex_joni, the link?
fenn: depends on the whole system
heh i guess that's like asking "how much does a factory cost"
fenn: starts at about 60-70k
the smallest ones
goes up to.. there's no limit
seen 5M+ systems
where does all the money go?
fenn: indeed amazing, 120m X, 20m Y, 7m Z, 3m X', plus the robot
with 0.01 mm accuracy overall
alex_joni, the link?
DanF_DrC: what link?
for the 3000$ ac motor
as I asked a couple of times now
there is no link ;)
a product with no mention on the web?
industry hates change
fenn: it's not that
it's just we don't worry about selling the motors
we just supply them to our customers
so if you buy a robot, you'll get spare motors when they brake
you'll have part numbers & all
do youhave a picture of a robot where it is used then? to get a feel for the size
[11:29:49] <alex_joni> http://www.cloos.de/deutsch/produkte/Kompaktzellen-Anlagen/Bilder_Anlagen/C30_Einsatz_Popup.jpg
[11:30:09] <alex_joni> http://www.cloos.de/deutsch/produkte/Systemloesungen/Branchen/Branchen_64.php
[11:30:31] <alex_joni> http://www.cloos.de/english/produkte/Systemloesungen/Branchen/Branchen.php
<-same thing in english
how heavy is such a 3k$ motor?
or does it have a wattage spec
about 5kg or so. 4kW or so
5kg for a 4kw motor!!
but that was just an example
is it water cooled or something?
fenn: now you know why they are 3k$
yep klumsy is prefered in the undustry :)
might be 10 :)
DanF_DrC: 4kw is humongous and 5kg is tiny
klumsy? think you don't have an idea what 4kW is
* fenn looks at DanF_DrC funny
4kw is little more than a common vacuum cleaner motor is what it is
fenn: the smaller motors (joint 4-6) are 1kW-ish
DanF_DrC: that is what we refer to as "sears horsepower"
its the rating the motor can withstand for a split second before the metal vaporizes
emperor's new clothes
do the math
15 amps at 110V is 1.7kw max
most household circuits have 15A breakers on them
fenn: and that's input power
so there's no way a vacuum cleaner will ever have 4kw
fenn, no they are usually spec'ed from 1000-2000w
but doubling it shouldn't make it cost like a car
that rating doesn't mean anything
DanF_DrC: just to get you an idea, sold a turn/tilt table recently uses 2 motors 3kW-ish
it's for workpieces up to 2500kg
every day i have this painful realization that everything is expensive
alex_joni, I take it you feel that's a point in itself or is it coming?
DanF_DrC: it was a point to help you understand how much power 3kW is
fenn, no a lot of things are quite cheap. but the nano is it 'business to business' all reason get lost
I thought 5000 pounds might be more perceptible to you
alex_joni, hehe ok
monstroously stupid but ok
* fenn goes to bed
IBM once sold 486s for 15k$ while clones of the same specs were sold for 1/5th
you let status quo dictate your beliefs and it doesn't impress me
DanF_DrC: again, it depends on what you want to accomplish
it has nothing to do with quality
overpriced is overpriced
no, I didn't say quality
I said what you want to accomplish
do you want to cut cardboard?
or do you want to cut steel at 1200IPM ?
that would be quality or specs
overpriced means overpriced
overpriced can be overpriced if you have where to chose from
like the ibm's of yesteryear
that sentence didn't make sense
say you are a big factory
please not a long story
you have certain contracts with your clients
and you have something like a few k$ for every hour downtime
you just don't get it. you desperately want the prices to be reasonable
not sure I follow your thoughts?
what do you want? a 3k motor to cost 100$ ?
what if it cost 100k$ for that motor? or a million. when would it be overpriced?
that's what I want yes
when I can get a cheaper one
and it should weigh 1/10th
with the same specs, or maybe comparable
* fenn gives DanF_DrC some superconducting wire
that's another aspect. I am not saying that you can find it cheaper anywhere else. that doesn't make the price reasonable
DanF_DrC: there are lots of motor suppliers out there
don't you think ONE of them would make a cheaper motor if they could?
and I don't mean 2.5k instead of 3k
nor do I
it's a phenomenon onto itself how these overpriced things can keep in business
did you study some economy?
lets take stepper drivers for example
not formally no
the gecko G320 is about 100$ or so
you can build your own L297/L298 for about 20$
which of these is overpriced?
* alex_joni says none
they both are worth their money
I meant G201
[11:49:01] <alex_joni> http://www.geckodrive.com/product.cfm?pid=11
lots of people will say 140$ (I just looked) for a simple stepper driver (even if it does microstepping) is way too much
I don't care for the concept 'worth their money'
so is the 3k$ ac motor
to some who can drown that massive overprice in other massive overprices
DanF_DrC: then simply don't buy it.. it's a free world
you have the choice of not buying it
and why don't you care for the concept 'worth their money' ?
don't you care how you spend your money?
or do you evaluate by amount only?
I evaluate by reason
like a small ac motor shouldn't cost as much as a full featured car
only tunnel vision can't see that
1. it's not a small motor (it's a very big one by very many standards)
2. a full featured car is more like 10k
there are chinese cars for 3k$ now
if you like I can see if I can find a link
but I think I would just be wasting my effort trying to convince you
no, we have <5k$ new cars over here
but I wouldn't dream of buyng one
of course that doesn't void the point in any way
it's just that I think 5k on a car like that is wasted money
it's cheap, yes, but it's very bad
so it's not worth it, or you might say it's overpriced
that's the motor?
wow that statement disgusts me a lot
that you would call a 3k$ car overpriced but that pos motor for the same price reasonable
it's a different thing, that's what I am trying to explain to you
I personally wouldn't buy either
no shit sherlock
the car is simply bad
the motor is of no use to me
but for people who need such motors, they are glad to buy them
you're generalizing your views on the world, that's your problem
i find it interesting that the motor page doesnt list horsepower anywhere
fenn: that depends on power supply, it says max amps
so if you use it at 600V you can calc. your kW
check performance graph
yes, but horsepower is usually used as a marketing tool
so it means people who are buying it are going on specifications alone
and brand loyalty/company reputation
fenn: normal people don't buy these motors
it's rather system designers who decide, and they try quite a few out before they say that is the motor we'll use
and baldor happily will provide lots of motors for testing for a robot company
but I agree that this is all 2-3 levels above the home user trying to fit a machine together
it is a pain in my ass for sure
all the RFQ stuff for one
baldor actually lists prices, which is weird
fenn: RFQ ?
request for quote
fenn: that's a strange ideology
I give you that
RFQ means ashamed at the price
hard to make intelligent decisions when you have to wait a couple days and mail 20 different companies
but there are various reasons for that
DanF_DrC: that's #1 reason
i dont understand why digikey can list prices but company xyz cant
fenn: I don't know about others, but I know why I don't list prices on my site
in fact digikey is my hero
and that is because _my_ users are ignorant
the lie has to linger long enough for some to believe the price is reasonable
they don't really know what they need
humans are such fools
alex_joni: so you're saying people will choose the lowest price and then bitch about it not doing what they want?
fenn: usually yes
* anonimasu has finally almost finished cleaning
I find that to be true
fenn: err, make that always
because, at least in my case, most of the decision factors have nfc about what the needed specs are
I mean when a big company buys some stuff, it's usually some manager who gets the decision
and he's a technical moron usually
the company I buy stuff off is the same with..
alex_joni, what kind of gearing is inside such a robot using such a motor?
DanF_DrC: lots of different types
depending on the joints
sure but give an example
not sure how they are called in english, sorry it's not my native language
DanF_DrC: google for it.. :)
anonimasu, I'll bet you 10$ you can't find it with google
alex_joni, gear ratio
inertia matching of motors?
1:20 or so
I could bet you 50 that it's on google..
[12:10:10] <anonimasu> http://www.google.se/search?hl=sv&q=inertia+matching&btnG=Google-s%C3%B6kning&meta=
of course they are backlash free
no doubt it's good engineering
betting against google is usually a bad idea i've found
DanF_DrC: and good engineering tends to have its price :)
the rotor inertia is what makes servos cheap/expensive..
anonimasu, I never asked for any inertia matching
DanF_DrC: but that is used to calc. the gear ratio
DanF_DrC: never figured out why the engineers are overpriced like that .. lol
alex_joni, there is no doubt it has a price
DanF_DrC: some robots have helical gears, some have ballscrews, some have timing belts, some have linear actuators
most ours have helical
worm gears arent so common
DanF_DrC: ever made a gear?
* fenn hasn't
i'm gonna have to though because i cant find the ones i need
fenn: normal gears are simple enough to make
fenn, no havne't
do you have the equip to do it?
fenn: even work gears have been used on robots (low power motors)
worm is often used in drills
drills are usualy planetary
ah yes I confused the two
so-called "worm drive" circular saws actually use cycloidal gearing
DanF_DrC: i have to make some fixtures, but yeah i have a lathe
(which i built from melted down scrap btw)
a lathe can stop at intervals?
DanF_DrC: it doesn't have to
yeah if you stop turning the handle :)
gear hobbing is a continuous process
how are the teeth done then?
usually gear get cut with special tooling, linked to the spindle speed
you know how a worm gear works right?
if you traverse the worm across the gear face as its cutting it will make gear teeth
gear hobs are simple .. but ingenious
i dont get why people use those form cutters.. such a bad idea
[12:18:59] <alex_joni> http://www.superior-ny.com/Superior-NY/Web%20Images/DSCN0028.JPG
a gear hob will cut the correct tooth for for multiple numbers of teeth on a pnion, fromt he same form cutter
how does that ensure even spacing when it closes at the back?
its neat how it gets the undercut correct on pinions with small diameters
* robin__ shuts up
robin__: i've got a question for you, along the same lines as this conversation actually
how come you need a laser to do lasercutting?
fenn, well, how else would you fo it?
why not use focused IR radiation from a blackbody
fenn, how does it ensure it fits when it comes round?
[12:21:42] <alex_joni> http://www.emachineshop.com/machines/Spur-gear-cutting.htm
DanF_DrC: you need to make the blank the correct diameter to start with
thats the same as "why not just use a very bright bulb"
yeah why doesnt it work
because its non-coherent
so you cant focus it on a tiny spot
how tiny does it have to be?
0.2mm or less
you want to do a laser cutter without a laser?
or at least etching
good luck ... :)
could probably be done. might not be easier to
fenn: you might get away with a big magnifying glass and the sun
you need to exceed the dmage threshold of the substrate
but you'd be etching away at 0.001mm/sec
i'm thinking high-wattage heaters cost less than hi-wattage lasers
or less :D
well, yeah, but non-coherent
fenn: compare the input powers, not outputs
robin__: does the pulsing action of the laser have an effect?
fenn: it does have a very BIG effect
i read about military lasers waiting for the puff of gas to clear the hole before firing again
we have no pulsing
robin__: some smaller powered YAG's have pulsing
like a couple ms
seen a tiny 150W, with 2.5kW pulses
oh flea power ones yeah
you can pulse them, mines CW
so pulsing doesnt improve the cutting action?
and yeah, its a trumpf
no pulsing makes it worse ..
some roots-blower type gas lasers pulse a bit ...
alright.. next question..
if you have low power, and need to do stuff, pulsing (as in Q swtitching) can help
how do you get square edges? or do you?
and what is the focal length of the lens
lots of the etchers/markers are pulsed I think ...
I do getg sq edges ..
fl is around 6"
how big around is the lens?
but only the centre 12mm or so is illuminated
ok so that triangle has tan(30mm/6")
you can get lenses from places like laser II VI
say you are cutting a piece of plexi 1 inch thick
so the spot is 2mm in dia at the top of the plexi
if its focused on the bottom
or 1mm on top, focused in middle, 1mm on bottom
ummm ... 1" ... you might be in trouble
for YAG you focus on the top
at what distance?
for CO2, just below the surface
you'll need co2 for plexi, yag ignores it
ah that's the other problem with lasers, you can't change the wavelength
well, co2 works on most stuff
not entirely true
you can if the lasing medium is multiline
like my argon lasers
you cut at 6" distance?
the back mirror is via a prism
from the lens to the workpiece, yes
there is a nozzle at 6" from the lens, sits 0.7mm above the workpiece
ok that would give close to square then
well, it gives sq
there is a waveguide effect of the molten steel
the nozzle just keeps spatter off the lense and keeps the work from oxidizing right?
or oxidizes it if you are doing steel
and eyes from stopping working
mmm .. the nozzle direct a stream of oxygen or nitrogen into the cut
about 2bar of 02 for steel
robin__, completely square it probably isn't
or 12bar of N2 for stainless and aluminium
DanF_DrC, better than 0.5degree in thin stuff
how wide is the kerf for say 1mm sheet
what is thin?
thin is 5mm and under
1mm? 0.3mm kerf
about 0.4mm kerf at 5mm
can you cut steel at all without using O2?
fenn, like the motors, lasers are not expensive because they have to be
a 10kw lightbulb cutter would cost a lot too
but it wouldnt work
i dont get why it wouldnt work
robin__, of course it would
you couldnt focus it onto a small spot ...
if you have the energy coming from a point source
sigh all you want
ok lets say you're focusing light from the sun
that would be WORSE
fenn: why dont you just cut with electrons?
perfectly parallel rays
fenn: what kind of lightsource is that?
anonimasu: vacuum pump is too big and crappy
fenn perfectly parralel rays on multiple frequencies .. OK, keep going
ok sunlight through lense onto steel
you're floating in outer space so you dont have to worry about the earth tilting or anything
can you cut through steel with that light?
not easily ...
the sun has a significant size that would hamper focusing
with o2 assist
no that would aid focussing
DanF_DrC: silence you
scenario 2, you use a mirror to focus the sun onto a spot
remember a bigger lens can focus to a small er spot
no more chromatic abberation
why wouldn't that work?
well, you cant get it into a small spot
think of it like waves
wavelength of IR is like 1000nm
the ocean waves have lots of energy right?
try to combine all the energy of a whole beach into one spot ...
stuff will start to cancel out
robin__, that was an unusually bad example :)
it will do destructive interference in some places and constructive in others
besides some tsunamies are focused fairly well
nah that's just raw power
photons do not just "add up" regardless .. you need coherence for tiny spots to be effective
if you have enough power they'll be destructive.. but it's still not pointed..
this is also why you need circular polarization of the beam
fenn, you will find that depending on coast shape some regions are not affected while others are wasted
linearly polarised lasers are no use for cutting
they cut well in one directiom crap in another
hmm i've never heard that before
all industrial lasers have a lamda/8 delay and a splitter
serch for co2 phase retarder
since you can cut paper with sun it's a simple matter of increasing power. it might not in any way be as good or even practical but surely can be done
are you cutting the papaer really?
or are you just heating it up to the flaming point of the material?
possibly .. with a field of huge mirrors ... and if you didnt mind a kerf wdth of 2mm plus
haha i love it
DanF_DrC: no you cannot cut paper that's the answer :P
my laser has 30Kw of arc lamps in it :)
paper dosent catch fire when you cut it with a laser isnt that right?
well, it does, locally,
thats cause there's a nitrogen jet blowing onit
ummm . compressed air ususally for paper
anonimasu, at 2000degrees even steel is impressed
i am thinking a telescope mirror made out of SiC and heated to 1000C or so
but lasers no doubt has significant advantages
woot? : ) why would you heat the mirror?
or if that's no good, a mirror and a spherical blackbody
heating the mirror is simpler
otherwise i'd have to cool the mirror :)
and that's no good
you want to cut with the blackbody rad from a large mirror?
hehe why?? : )
to get rid of the laser silly
why not a potent lamp? like a fusion light
they just call it that
look just buy my 450w co2 and be happy :)
�1000 and its yours :)
complete with 2 psus, vac pumps, controller box thing, cutting torch and spare glassware
are you sure thoose methods are feasible at all compared to a real laser?
something like a microwave driven gas light
* robin__ waits for any takers
look just buy my 450w co2 and be happy :)
complete with 2 psus, vac pumps, controller box thing, cutting torch and spare glassware
�1000 and its yours :)
anonimasu: no i have no idea
robin__: thats pretty cheap
shippings a bitch tho
sold to the man!
robin__ free shipping and it's a deal
weight is close to 800kg
do you have one in hand held robin__ : )
i'll buy it if you can store it long enough for me to sell it :)
robin__ 450w... damn, that's 220
thats the problem ...
DanF_DrC: a maser wouldnt have a tight enough spot because microwaves are so big
moving factory next week, need to clear it really
robin__: laser or complete laser engraver/cutter?
fenn, but a large mirror has a tight enough spot?
450W would cut metal
just the laser ... I have the motion system too, complete with bed for another �1000 :)
DanF_DrC: yeah but i'm using IR radiation not microwave
robin__: do you have a control?
fenn, you could power it with 1mm radiation
[12:54:33] <robin__> http://www.hw.ac.uk/mecWWW/amu/amu9.jpg
and you can have effects smaller than wavelenght
liek that ....
the PSU is the big box back right
that sure looks nice
is yours as pretty as that one
I have two ... one and a spare
mmm ... not quite as pretty
I started photoing it for ebay
how much power does it take to get the 450w?
not in one piece and working ... but all there
450W, about 15kw input
maybe 12Kw ...
my 700W yag takes 30Kw so its not bad
they shoud aim for around 100% efficient instead
or more when they are at it
robin__, what is it that you do? sell them?
heh you really want a fusion light huh
that'd be sweet
naw, better than that
brown's gas torch
umm.. mind over matter
reality engineering device
DanF_DrC, nah, I run a subcontract laser cutting company ... I seem to acquire old lasers like other people acquire old pcs
a device that just asks the universe to deliver a given laser intensity
no energy required
DanF_DrC: that's no fun
maybe you should stop drinking now
when you see the beam streaming from a hand held device you will think it is fun :)
why do you need a hand held device?
real men shoot lasers from their eyeballs
fenn: so he can cut crappy with it ;)
robin__, any competition for the lasers? magnetic cutting or something?
or is lasers the thing for now
plasma, waterjet, edm
electron beam machining
tons of stuff
then you have all the mechanical processes
what kind of crazy people use lasers to cut metal?!
plasma is the only real one .. and its crap :)
I was just thinking it was foolish to heat the metal up since it's just a plane of bonds you want loosened
waterjet is slow ...
edm is galcial
anyone know the principle in plasma?
isnt waterjet pretty fast nowdays
yeah an electric arc heats up a compressed air stream, ionizing it into a plasma
so a tazer more of less : )
the plasma goes through a spiral-shaped nozzle and begins to rotate,
the rotation creates a magnetic field which causes the plasma to contract into a tight stream
that's my understanding of it
the plasma is intially struck between the nozzle and electrode ...
hmm one would think that guiding plasma could be hazardous
then the arc is transferred to the workpiece
DanF_DrC, well spotted
DanF_DrC, one fuck up and your nozzel is toasted
transfered how? just inertia?
its blown out by compressed air
the circuit to the nozzel os brokemn and the one to the workpiece is made
and there is the airflow ...
yeah but you can't blow it out since the walls would be damaged
the workpiece is grounded, and the initial arc starter in the nozzle is grounded too
DanF_DrC: the nozzle is made of high temp ceramic
fenn, that wouldn't help :)
but the nozzel is isilated during cutting
the beam is 30k
fenn, no, it copper
I've never seen that-..
as robin said it's copper..
hmm the one i used was ceramic
I used to sell plasma systems ...
the thing that protect the nozzle is plastic..
looked like a pasta noodle kinda
we made more money on the large quantities of nozzels than on the systems :)
deep square threads
robin__: piercing with plasma/not tilting the torch isnt to good
robin__, so all the electrons are kept at the gun? and only the positive cores are sent out?
anonimasu, all the CNC systems pierce straight
robin__: might be why they eat nozzles..
they change torch height for piercing right?
fenn, yes they do
oh well if it isnt mister capitalist himself
pierce height is fixed .. then after that it varies to maintain a constant arc voltage during the cut
hey rich boy! ;)
robin__: nozzles last forever if you dont blow the melted metal back into them
anonimasu, to an extent ... true. they get a bit crappy from the initial arc process
Hypertherm are the guys to see about that
they claim up to 800 starts from a single electrode ...
robin__, one thing you might now, has the lasers gotten a lot smaller over the years?
I wanted to visit miller /hobart and try plasma on my trip but got too busy with other stuff
DanF_DrC, soemwhat, yes. solidstate lasers are a bit smaller I guess ... lots of diodes pointing at a YAG rod, and disc lasers are good for their size .. but there is no benefit really from small size
indistrially, space is not aproblem
price is however
price has gone down too no?
smaller != cheaper
not really, no
hmm, should have
my 4$ 5mw laser certainly would have cost more 20 years ago
sure .. but thats because they sell millions now
the market for multi-kilowatt lasers is still small
I was messing with a 50w diode pumped yag a friend bought
sure but same solid state tech used in yours I would imagine
35W CO2 12" x 24" == $15,000 USD
wants to start a marking business his wife can run
DanF_DrC, nah ...
les_w, good money on marking ...
we tried it some
I have to say pretty neat
cost was $50k
DanF_DrC, nah, mine is 30Kw of arc lamps onto a YAG rod ... solid state as it gets in this business
DanF_DrC: Like the model number on router bits
we marked metals like aluminum, steel, and titanium
was suprised the aluminum marked so well
qswitched thing I take it?
Ti is dark and marked very well
yeah q switched
the damage threshold on Ti is very high ...
to the part?
you need a lot of energy to do anything to it
who needs their things marked?
and can't do it themselves
not sure...freind asked for help but he needs mostly marketing help
Colored Laser Engraving http://www.color-laser-engraver.com/what.htm
well, nearly everyone ... its a booming market
the system is very easy to use...nice cam comes with it
I'll shoot him any business I have
neat that it can make colors with light
A friend got a trumpf one ... on appro. "have it for 3 months, see if theres any work"
hes flat out on it now
* robin__ nods
what kind of jobs?
small parts ... aircraft bits, just "engineering components" mainly
woops here comes big backhoe...we are digging some stumps this morning
thanks for link
post pics !
they laser engrave IC packages?
of the golf course work?
thats normal in the semi industry ... mostly done in house though
so who needs marking again? : )
DanF_DrC: go to any hardware store and look at the taps
they are all laser engraved because you cant stamp the numbers onto the tap without distorting it
would just think that if a single person could buy the marker then the factory could have one too. but maybe not
taps, router bits, endmills, etc
can you spot the difference between an 8mm thread and a 5/16 thread?
I wish they'd do that to drills.. too
I hate it when the markings wear away
drills arent good for anything accurate
just pick one taht looks about right :)
anonimasu and thus drill indexes were invented =)
heh i made a suction-fit endmill holder with crappy chinese drills
fenn: drills are very accurate..
but they just dont make round holes ;)
when a motor has the ability to determine position it is a servo right?
a servo is more than just a regular DC motor with an encoder
that was actually a rhetorical educational question : )
I already knew that it was true :)
fenn, that's the common understanding of the word but not sure it's true
it is lower inertia, has finer commutator segments, more precise bearings and loewr friction brushes
phantom was having problems converting a dc motor for use in a cnc machine
said he couldn't move the rotor less than 120 degrees
it was a DC motor too
heh time for bed for real now
DanF_DrC: you should ask les about threadmill motors..
DanF_DrC: if you are interested in them..
not aware of any interest in them
didn't know the term even
like you get for free from an exercise equipment place
but I take it it is the principle often used in servos
ah you mean the exercise device
you can use them with encoders.. for cnc machines
they are pretty good..
do they have encoders?
not as far as I know..
so it's an electrical motor?
ask les when he gets back :)
* anonimasu has no clue but you can use them as servos nicely
thanks but I'm not a big fan of the scrapheap challenge approach
* anonimasu sighs
you can buy them new too cheaper then servos..
that would be better but still missing the encoder
not my problem really you keep saying servos with encoders are too expensive.. and that you cant understand why..
stop making problems for yourself.. :D
I think it would be better if you stop giving me crap advice : )
these doesn't look too expensive either: http://www.transmotec.com/product.asp?cat=9
thoose servos rock
ah, try to buy them in single qt..
transmotec sucks for that
yeah but thoose arent free/cheap either
I tried to get a quote on some solenoids from them at work.. for a prototype, they hardly wanted to discuss anything in a quantity < 20
they do have a pricelist for single piece tho
but granted it is more expensive. a practice I don't like either
does anyone have the actual yahoo group name for the geckodrive grex?
rayh-away is now known as rayh
yep found it just a few seconds ago : )
could someone tell me why my stepper driver gives double pulses only when my stepper motor is connected to it?
probably noise getting back into the driver cicuit. does it go away when you lower the supply voltage?
it was 20 volts initially. it disappeared at 7 volts. but now the motor isn't strong enough
it seems like the disturbances goes backwards from the motor through the transistor h-bridge, and to the digital logics circuits!
it it was induced disturbances from the cables and wires and so on it would behave this way even without the motor. it performs normally without a motor hooked to it.
what brand is it Bo-Dick?
i just fired up my old propane pick up... motor runs like a clock.. but EVERY liquid is near empty... thd the powersteering seems to have siezed
she's gonna need some LOVE
she's gonna take the iron and work ..
hey guys, i'm happy to announce you I done my website !
[16:35:15] <giacus> http://www.giacus.org/
I just learn xhtml and css in few hours
dunno how I did :(
the only thing i've doubts is the layout colour
is it for girls ? O_O
And the whole list hammers the giacus website. Almost as bad as a slashdot attack.
hey rayh it is very light
only png images ;)
liquid layout should be ok for small devices (pda)
I've to test it
xhtml transitional seems to be pretty friendly
strict was hard ..
at least for me, first time I write html code by hand
and working, I found bluefish its a nice editor
a funny thing I discovered
png transparent images background isint supported by IE
hello, I'm going to do a milling machine myself. I want to use emc. I don't want to buy any made hardware, is there any free hardware (motor drivers,etc) is ready for emc? I was thinking to make the milling with FPGA's and dc motors with encoders to close the loop
i'm a little lost cause i'm beginning
are you able to hack drivers and write low level code ?
i think so
well, emc is open as you know
many peoples use homeade drivers
not homemade motors.. for what I know
i want something to begin with, i'm speaking about the motor drivers
no, homemade motors no..:D
servo drivers ?
there's a pseudo-pwm in emc2
like the printers
and encoder, pid, etc
you can find complete documentation on the wiki
ahaps, and is there any free hardware ?
schematics or vhdl or something
I don't want to buy the gecko drivers
I bought it ..
it's too much money for me, 3 drivers
you can try to build your own drivers
yes, that's the thing
but remember require a lot of time, and maybe the result will be poor
lot of math ..
I suggest you to start reading the wiki
yes, so i see there are no free drivers in the web that are compatible with emc
depend on what you want to drive
you have built it with the gecko drivers?
vegga: Here's a free design that you can hook to your PC with a parallel port. It's for stepper drivers: http://pminmo.com/l297-8/l297-8.htm
vegga: It's not based on FPGA however
thanks a lot jeplet, it's a pitty that they are not servos jeje
vegga: do you know the mesa FPGA PCI card
vegga: I should build my next machine and use geckos servodrive
Imperator_: yes, i was reading now the specs
Imperator_: this is the thing I like
we have made here some own extension boards
anyone uses the mesa card for the machine?
I don't know but some have bought the card
Imperator_: ahaps, this is my will, doing my own fpga board like the mesa one
dont build it by yourself
vegga: why building your own?
it is so cheap, that makes no sense
Imperator_: i thought that is possible to do a microblaze processor in the fpga whith linux, so the pc is not needed
[17:11:28] <anonimasu> http://www.imec.be/rtlinux/
that's a better bet..
take a industrial pc or much cheaper a via epia board
Imperator_: have any first-hand experience with how emc performs on those via boards?
how many axes can i hit simultaniosly with emc2
but someone here has a epia board, maybe rayh knows hwo
thx... should work
I also have epia
im thinkin of a paraglider simulater thats .. interactive
what kind of ports does the epia boards have?
ah nm found the spec
HAL allows for 8 but EMC only handles 6 right now.
thx ray.. so a plc axis is possible??
no com port..
The comparable mesa card has software for 12.
epia boards have com ports
In fact you could build a plc axis in HAL without using any emc interface.
Like a pick and place or any set of looping motions.
rayh; i see the mesa card is very interesting, and how does it connect to the pc, via pci? i see it's a pc104+
look at the m20i
The one that we have software for is the m5i20 and it's pci.
1 pitch - 2 for roll - 2 for yah - 2 for brakes and 2 for speed bar
I sent a pc104 card to Paul but I've not seen any software for it.
Imperator_: how does the mesa behave?
Okay from what I've herd.
how do you mean that ?
I've got one here but must set it up with motors before I'll know from personal experience.
i like the 4i34m
The owner of Mesa has just started putting files in the repository.
it would be beautiful having these in opencores.org
7I30 Quad 100 Watt H-bridges for 4I27,4I34,4I65,5I20,7I60
anonimasu: i made my own breakout boards, the counter card works fine, for the DAC board i have to chanche a lot in the fpga software that is not done right now. the card itself is very good
you could really create a neat motor driver on the fpga..
or well thoose 0-10v output boards..
and real servoamps..
err power sSoftDMC Digital Motion Control firmware for FPGA based I/O cards
SoftDMC Digital Motion Control firmware for FPGA based I/O cards
that has done mesanet already with that breakoutboard you can buy
but i like a real servo amp more thats why i made a board with a real DAC
could someone tell me what causes disturbances from the motor coil back to the TTL circuits in my stepper driver design? http://www.carmi.se/misterstarshine/img/block.gif
did you put caps on all the circuits?
Bo-Dick: where are you bypass caps?
and protection diodes?
uuuhm. "bypass caps"?
you need to read more electronics books
every circuit makes electrical noise
jmkasunich: at 20V this isn't THAT bad :)
u mean those near the voltage regs?
motor circiuts make tons of noise
caps are used to filter it out
where would you put the caps if you where in my situation?
you should have 1-10uf at the input and output of each voltage regulator, 0.1uF at each chip, and several hundred uF at the H bridge (in parallel with some high-freq caps like 0.1uF)
also, why the regulator and current limiter on the motor supply?
the current limiter limits the current to the motors coils
you mean the LM317 is redundant?
a resistor would do that too
Bo-Dick: what voltage are the motors referenced?
an active current limiter is more responsive and powerful
i'm gonna have a maximum voltage of 30 voolts
most drives use PWM to the transistors to control current, I didn't realize you weren't doing that
right now i'm testin' the device with only 20 volts
so yes, you need a limiter
but you don't need the LM317
i've got a linear current limiter
jmkasunich: yes, the current limiter, but running at 23V instead of 20V should be fine too
this circuit is increddibly inefficient
so I wouldn't put the LM317
i'm gonna remove the LM317
Bo-Dick: what is the motor volts and amps rating?
you only need to worry about the voltage if it's ~ 10 times more than the motor rating
alex: not true, that is for PWM drives
i'm gonna run the motors at around 200mA
jmkasunich: oh, right.. this is not PWM
tiny tiny motors?
wow, are those really 2n2222 and 2n2907 transistors?
jmkasunich: this is tiny: http://www.livescience.com/technology/050915_smallest_robot.html
no, ignore the transistor names
they are TIP31C and TIP32C
and caps at the H bridge
from top to bottom
i don't know how to connect the caps at the bridge
from top to bottom
Bo-Dick: on the power supply to the bridge
top of upper diode to bottom of lower diode = supply to ground
hmm.. is the driving of those transistors ok?
not for any real power level
but this is so tiny it might be ok
200mA / transistor beta of maybe 50 = 4mA required
I would be concearned about shorting the PSU by mistake
4mA * 2.7K = 10V
I take that back, the driver isn't ok
the psu can't be shorted!
alex: that common emitter connection can't get a shoot-thru fault
Bo-Dick: are the TIP31 and 32 darlingtons, or regular transistors?
they're in a darlington config. it isn't shown in the image
what is the minimum current gain (beta, or hfe on the data sheet)?
i think it's aroung 100 somewhere
ok, so for 200mA load current you need 2mA base current
on the side of the bridge that is high, the base current is supplied thru the 2.7K resistor
so you have 2mA * 2.7K = 5.4 volts drop across the resistor
another 1.2V drop across the darlington
so the output can never get closer than 6.6V below the supply
and that 6.6V * 200mA is dissipated in the top transistor
i've got heat sinks
top? or first?
since you are running such tiny currents, it might be OK, but there is no way this circuit can be scaled up for bigger motors
its horribly inefficient
i'm aware of that
but the real problem now is that the TTL circuits get so much disturbance they flippin around out of control
this only happens when the motor is hooked to the driver
otherwise the signal looks fine on the oscilloscope
what is the physical layout of the circuit like?
(schematics don't show stray inductance and capacitance, etc)
the ttl are on a separate board
the h-bridges on a separate board
that board has step and dir inputs, two outputs, +5 and ground, right?
(the ttl board)
and the h bridge board has +20, ground, and two inputs
where is the 7805?
on the ttl board?
no it's at the supply
on another board?
right now i've hooked the supply and current limiter on a breadboard
can you post a pic?
the ttl board looks like this: http://www.carmi.se/misterstarshine/Projects/logic.jpg
this is almost impossible to do in words
no caps anywhere
[18:19:28] <Bo-Dick> http://www.carmi.se/misterstarshine/Projects/logic_rear.jpg
giacus is now known as giacus_afk
i could always wrap the ttl board in a ground-foil
you should have a 0.1uF or 0.01uF cap from Vcc to Gnd at _every_ TTL chip
that is the first rule of digital electronics
install chips, install caps, then start wiring
can they break without this protection?
break as in be destroyed, maybe
break as in not work right, definitely
in fact two of the ic's you see broke without an apparent reason
so far i've learnt that i should do three things to fix these problems. 1) caps on the voltage regulator 2) caps on every TTL ic 3) caps at the h-bridges. is that all to it?
thats a start
power electronics can be very tricky
stray inductance and stray capacitance can really mess things up
i never fully understood how the caps should be applied to the h-bridges
fortunately you are running at such low power you can get away with a lot
from the top of the bridge to the bottom
just across the whole bridge?
physically near the bridge then?
all h-bridges are in parallel
i need one cap for each bridge then?
Bo-Dick: 2 caps / bridge
that depends on the layout
one small, one large ;)
got a pic of the bridge?
[18:26:25] <Bo-Dick> http://www.carmi.se/misterstarshine/Projects/darlingbridge.gif
the diodes are missing in the image!
you need a high frequency cap (0.1uF maybe) at each half-bridge (8 total if you have 4 H-bridges)
I meant a photo, showing how they are layed out
if they are close to gether, you could probably have one 100uF cap for all four, as long as you have the small caps at each one
[18:28:24] <Bo-Dick> http://www.carmi.se/misterstarshine/Projects/drive.jpg
[18:28:54] <Bo-Dick> http://www.carmi.se/misterstarshine/Projects/under.jpg
[18:29:12] <Bo-Dick> http://www.carmi.se/misterstarshine/Projects/closeup.jpg
what are the round transistors?
(the TIP31 and 32 are the TO-220 ones, right?
and the diodes have blue tubing around their leads
what are they for?
the blue tubings are for isolation
what are the N12101
they are transistors
they are the first step in the darlingtons
but what are they for?????!?!?!?!?
I thought you said the TIP31 was a darlington?
they are arranged in darlington layout he said
now you say you made the darlington yourself with two transistors
in the block diagram i substituted the darlington pair in one symbol. sorry for the confusion
but apparently caps can be added to the design in order to reduce noise.
I would add one 0.1uF from the collector of Q31 to the collector of Q40
another from the collector of Q36 to the collector fo Q39
same for each bridge, total of 8
in fact the 7406's are on a separate board as well. http://www.carmi.se/misterstarshine/Projects/buffer.jpg
and one 100uF across the power supply terminals of the bridge board
i've got a lot of soldering to do now.
any particular reason for the 3W 2.7K resistors?
to stand the voltage
20V / 2.7K = 7.4mA * 20V = 0.148W you could have used 1/4W
or 1/2 watt to be very conservative
i was initially thought to be designed for a higher voltage. but from this standpoint they do nothing but take up a lot of space.
the 7406s are only good for 30 or 40 volts max aren't they?
if they are rated for 40, you shouldn't run the supply over 30
they're rated for 30
actually, without caps, I bet you get more than 40V spikes when you switch the transistors
well one 7406 got broke
thats probably why
do you think the caps will sort this out?
without caps on the bridges there is no way it can work
with caps on the bridges, probably (but other things could still be wrong)
would the caps on the bridges affect the responsiveness of the stepper driver?
the caps on the bridges will keep it from blowing itself up
"Capt, she's gonna blow!"
well at such power, "blow" is a bit of an exageration
the ones I work on do blow, and very loud
the bridge-board has eight h-bridges. that will need 16 0.1uF caps on the collectors. will it be sufficient to add one 100uF at the supply rails on that board?
jmkasunich: Blow as in poof! Not as in knock out the north wall =)
Bo-Dick: I can'
I can't say for sure
it's worth trying out anyway.
remember, I'm used to working with much larger and faster switching stuff
i wanna thank you for all help. you've been incredibly helpful.
so I might be recommending something that is overkill for you
but you definitely need the 100uF
your darlingtons switch slower than mosfets, so maybe you don't need the 0.1uF (or need as many)
i'm gonna add them anyway i think
thanks for all help particularly you jmkasunich!
jmkasunich: wondering what he wants to do.. I mean why not just build a L297/298 driver
the construction technique says he has a very low budget, or very limited sources of parts
(I wonder where he is?)
at least the webpage is
low budget. (he also thought steppers where a lot simpler than he knows now)
ah that one
ah bo dick?
he's spent more time then he would have needed collecting tin cans to afford a gecko
I have to admit - I started pretty much his route. about 10 years ago. descrete componants -> got the theory down pretty good. went to a integrated stepping chip which was pwm - then decided that I needed microstepping. now we get cheap compumotor stepping drives from ebay among others.
for the power level hes working at he could use a xylotex at about 1/3 the cost of a gecko
it's not as cool though, but the easy way is usually good if you want to make parts reasonably quick
sounds like he sorta wants to learn too
I like to do discrete design too
but he needs to read more before he starts building
and he should only build one axis and get that working before duplicating it 4 or 8 times
Jymmm: yeah like "where can I get schematics for geckos the parts must be like $8"
kinda sounds like he built the first circuit he found
anonimasu: Is that what he said?
Jymmm: werent you here before?
in and out
yeah.. that was what was said.. in the very beginning
basically stepper drivers are so easy I dont get how they can be so expensive..
I am kind of curious about designing a stepper driver though.. for the fun of it..
I suck at electronics
anonimasu design a controller
I have a degree and suck at it ;)
like the thing Jon sells, but w/o driver dependancy
I'd love to get into fpga's..
what the heck does fpga stand for?
field-programmable gate array
field programable gate array
what happens when I screw up my design: http://home.att.net/~jmkasunich/Pics/CapBang1.jpg
[19:13:28] <jepler> http://www.google.com/search?q=define%3Afpga
jmkasunich where you in the room at the time?
jmkasunich: you rock!
was that a electrolitic?
jmkasunich: nice -- how tall is that cap?
8" tall, 3" dia
jmkasunich OUCH! Those suckers are LOUD when they pop
bet that made a little noise
that's why you rock ^_^
I remeber that your company built vfds..
anonimasu: Build a 500KHz PCI parallel port =)
anonimasu: Do you know what a PCI slot is?
anonimasu: Do you know what a paralle port is?
and I know pci is hell-ish to design boards for
anonimasu like that board you bought
yeah I know..
me (in the middle) working on a drive in the field
[19:17:36] <jmkasunich> http://home.att.net/~jmkasunich/Pics/LF_MCC.JPG
but no driver dependacies... pure HW solution
nothing like changing the firmware on the fly.....
whos the guy in the middle? Reminds me of Chong
Jymmm: isnt the usc protocol documented nicely
I think I'm gonna learn a thing or two about fpga's.. they are a nice technology
anonimasu: I REALLY hate driver dependancies... got bit on the ass about 10 years ago BIG TIME
How do faunic do it?
yeah... dedicated IO ?
dont they run the motion control/interpolation on separate controllers?
like a mesa card of srots?
which does what over paraport?
has to do SOMETHING =)
might even be like a pci card..
like the galilmc pci cards..
brb, having something to eat
Heh... SWP either gave me the wrong flight number, or he's gonna be landing 400 miles of where he think he is :o
heh, we'll find out in about 20 mminutes =)
is he comming to you=
yeah, has a electronics conf here this week
Okay. I grew up in Modesto, went to school in Watsonville and in the Napa valley.
More'n you wanted to know.
Central Valley - ouch!
That was long ago.
I bet =)
well at least he had sense enough to leave.. ;-)
I wilt with the heat and the humidity
rayh... I have reservations for plane and car.. for Galesburg
Great. Looking forward to seeing you there again.
Hopefully the weather will be more bearable
and the projects not quite so intense
I'm looking for a way to sequence jobs on emc... any ideas?
ray must be thinking
dave-e: what do you mean by sequence?
hi, btw ;)
I would like to run several jobs one right after the other....
automagically loading into emc and starting
dave-e: concatenate the files?
I have reasons for keeping the separate...makes restarting easier
otherwise cat on the files makes good sense
ray is apparently still plugged into the phone
Hi K4ts. Saw your pic on giacus's site.
opps! he back
dave-e: there are some solutions.. but all of them require some coding I'm afraid
well this needs to be something that several people need before any time gets spend on it
dave-e: maybe the work on halui will permit this
I'll keep it in mind
I'm not much of a coder but an outline of the approach would be interesting
do you know about halui?
halui is a HAL User Interface which will allow you to build a hardware User Interface using knobs & switches & leds
lots of potential there
yeah, but also far away
does ubuntu automatially come up in 640X480 if it doesn't get shut down properly or is it my computer?
I've not seen that behavior
it's been pretty stable for me
could be my kvm switch also I suppose.
and I can break almost anything...ask ray
we lost power here this weekend
could be - it might not be able to read DDC from your monitor
I didn't have the computer selected when I booted it
This nickname is owned by someone else
If this is your nickname, type /msg NickServ IDENTIFY <password>
[21:29:01] <skunkworks> http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl/emcinfo.pl?Sample_HAL_And_ClassicLadder
where are these pictures now?
* giacus don't know ..
Hi jackey. How is it going?
skunkworks: give me a few minutes.. ok?
I'm going to remove pictures from my new website ..
K4ts: seen my photo and sayd is too dark ..
The one on the main page?
I was thinking to dark is better
Yes it is a little dark ;)
don't show the bad face :)
well.. removing it
too much pictures around :P
I think the reason is another ..
K4ts: is jealous
ok, so can I put pamela andersond in a banner in the right side of the website ? :P
just to balance ..
K4ts: I'm kidding !
turn off the damn tv
mi mandi tutte le mie foto
devo fare un mio album
should I send you all my photos ?
but you can find all in the website/gallery !
but plese .. read the terms before
as well they are gpl !
you know ?
send me an email request
I will see what I can do for you ok ?
non sono tutte
giacus is now known as giacus_xhtml
sorry .. :(
just wait some day
you can start with albums already are online
K4ts: what are U using to build the albums ?
skunkworks: sorry, don't have those
I mailed steve to get them
thats ok. Thanks
Just playing around with demo_step_cl
giacus_xhtml is now known as giacus
have not had ladder logic sense college
skunkworks: I didn't know anyone linked images from the wiki to the old linuxcnc.org website :(
oops. I noticed where it was pointing to. :)
skunkworks: sorry :(
just searching my ie cache just to be sure I don't have them. Doubt it though
not here - I will double check at home.
Clasic ladder is pretty neat.
yeah, and easy to use
I mean the ladder
ok, guys I'm off to bed
good night everyone
G night alex_joni
K4ts: what should I put in <meta name="keywords" content= "" ?
porn, mp3, divx, crack, warez ?
cnc, robot, robots,
00:26 <K4ts> ah
00:27 <K4ts> ma io nemmeno
00:27 <K4ts> ho sto ddc
K4ts: sayd she dont have dcc
who taked it ? O_O
jmkasunich is now known as jmk_away
walk with me here. I played with CL today just to look around (very cool) using demo_step_cl
I am thinking on how this would work for one of my applications. we have a 62 tool position tool changer. Each tool has a 9 or 12 bit number on them (don't exactly remember). Here is how it normally works. you call a tool say T100. the machine runs the changer reading each tool untill it reads tool 100. it the runs it for 2 more positions until it is over the spindle ready for change.
wow 62 tool position
could this be done as it is set using hal and cl without any coding?
yes 62 :)
I dont reach 7 tool in all :(