Guest179 is now known as skunkworks
once I got the kb to work
doing a plain install from CD without the live thing ..
grub installed and stuck right
I've never been particularly fond of live CDs
it even seems to like my Mesa card :)
you sound surprized
given in the past how anyting EMC related seemed to be based on goats blood scarifices and deep magic .. i was a bit
i love the "copy this setup over, create desktop icon" functionality
oops. closed the terminal
as a user, do you think the relatively flat list of sample configs is good? do you think a hierarchical tree would be better?
there is some hierarchy
one level deep for each root dir
was not a problem
I found what I needed
maybe a good idea to have "3 axis stepper mill" really close to the top though
ok - just wondering. I'm working on a tree now
actually, 3-axis stepper mill should be a symlink to stepconf these days
hmm, thats a thought
is it still easy to mix stuff .. like 3 axis of servo, plus an axis of stepper for some random thing
perhaps we should have one or more stepconf generated configs, complete with whatever trick files stepconf uses when you go back and tweak the config
robin: of course
just a bit of HAL tweaking?
sorry, itas ben a long time :)
brain has forgotten much
ok off to bed
see you around
it's not easy with stepconf, unless the servo drives are step-to-servo like geckos
sinece it's meant for stepper machines
whats not? mixing axes?
using a combo of steppers and servos, with stepconf taking care of the details for you
anything like that involves either skipping stepconf, or using it only to get a start, and then doing the rest like a real man
doing it is easy with a text editor and a brain
there's a change I'd love to see in the various HAL drivers and components, which would do two things for us: 1) allow a sim version to be used to do real configurations and 2) throw errors when the correct hardware isn't found
actually, it's two changes
1 is to have a sim mode in the drivers, or have some pseudo-auto-generated pin/func/param list for each driver
the second change would be to explicitly list every piece of hardware that's expected to be found
(thinking largely of the PPMC here, but it's applicable to others as well)
I don't get it
having drivers that auto-detect hardware is kinda wrong
what if a piece of hardware dies?
then the pins that it exports aren't there, and the config fails
the system won't load, but the reason will be hidden somewhere
what if you add hardware, like another DAC card, to the PPMC, which changes the names of all the pins you have now?
(or does it?)
that depends on EPP bus addressing I think
your original statement was very generic
add a Mesa card - which is which
I am adamantly opposed to anything that doesn't let you choose to load the driver and then see what it gives you
discoverability is VERY important
well, that could also be an option - load --discover or something like that
load my_module config=DETECT
heh - I was about to suggest that the other case should be the option
loadrt some_driver better_find=far,bar,andblat
well, that should be a required parameter for normal operation
you really want to get an error if the hardware isn't what you think it should be
auto-detection is good, error detection is also good
but the definition of an "error" depends on the user
if I have a foo card, then abscence of foo is an error
yes, it depends on the expected hardware
if you have a bar card, abscence of bar is an error
if I load the bar driver, it ignores foos
so the _user_ should be the one specifiying (explicitly) what he wants to see
I'm talking about ppmc, where one driver support foo and bar
I see it similarly to the way you see setting up a system
if you load a foo driver, and it doesn't find a foo, it prints to dmesg and exits (for those that can do that)
you start with bare HAL and tune servos (for instance), then put the numbers you found into the EMC config
I'm thinking that hardware detection should be that way as well
first make sure you've got what you think you should, by using the detect funciton
then put that information into your config, and hope to hell you get an error if anything changes that you didn't do on purpose
we're arguing over a detail I think
I want the detect to be the default - why should a newbie have to figure that out
the added advantage is that the driver is told exactly what should be there at load time, so there can be a "fake this setup" option :)
ie, export pins but don't twiddle with hardware
the ONLY time you want that checking is once the config is done
sure, could be
but at this point, I don't think you can explicitly tell a driver that there should be two of X (STG, Mesa, Motenc ...) - they detect the number of cards
that could be changed of course
although I have grown to absolutely hate insmod params
actually, it should be possible to write a "hardware detector" program
something that looks at lsmod, lspci, etc. and compares to a list of known hardware
won't work for everything though - I think ISA cards (and parports, really) are about impossible to detect
you write that.....
heh - eventually ;)
I'm just learning python and tcl, remember?
personally, I think trying to write things that replace a human brain is hard
regardless of the language
well, there are always better idiots. eventually my programming skill will catch up with the bottom of the lot
oh hmm. I guess I should pack up and get to my plane
on your way to tormach?
see - start complaining and the time just flies
nope, close though
going to the In-Laws, headed for Green Bay from Chicago right now
maybe I'll get a chance to play with the lathe setup some day
gotta run. thanks for the chat - see you
well I'm committed... it's sure easier to start a retrofit when the machine won't run as-is.
I mapped out pretty much all the wiring that'll stay
did you start disconnecting stuff?
yes it's pretty well torn apart
I figured out why the spindle brake doesn't work -- it's missing
no other big surprises though
a VFD should be able to handle braking
yeah that'll be nice
but, I'll have to leave one of the clutches engaged for it to work
twh clutches for two different drive ratios?
dog clutches, or friction ones?
looks like friction
like an AC compressor
engage both at the same time - instant brake
I thought about that. I might try it.
might be best to make sure the motor is off before doing that.
friction brakes (or clutches) wear, VFDs don't, so using the VFD would probably be better
there would be plenty of room for a heater under the big cabinet
if I want to rigid tap, I'll probably need a brake heater
however, engaging both clutches after it is stopped might be a convenient lock when changing chucks, etc
it has a locking pin for that
you mean a DB resistor?
I saw a retrofit where a guy used an electric stove element as the DB resistor - simple, rugged, cheap
smart. I bet they have about the right resistance.
and they can take 240V continuously
put it in a screen box on the top
I'm gonna do something novel and try to be in bed before midnight
darn, he left
hi chris how is the lathe coming?
great. I started tearing it apart in earnest tonight.
it is fun taking things apart
I mapped out all the wiring, proxes, clutches, relays, etc. that I will keep.
can you keep the majority?
I have not found any big surprises yet. I will be able to pull it off.
I had no doubt
yes all the magnetics and isolation is pretty much there and working
it will mostly be a matter of wiring it up and writing ladders
just a little time
homing is unusual on it - it will take some finesse
is there anything you need - I will try to find something here
how could homing be unusual?
jon elson's resolver boards? :-)
I haven't heard much from him
I think I have everything, but I will keep your offer in mind, thank you
last I heard, he is waiting for his pcbs to be made.
that's all I know too
homing is unusual because there are many indexes per ballscrew revolution since the resolver is geared up. so they have a coarse home switch (slide) and a fine home switch (prox on the ballscrew pulley)
I think I will have to AND the fine home switch and the actual index and feed that to my index
this will make it so there is only one apparent index per ballscrew rev
yes - unusual
another problem is the Z home is somewhere in the middle of travel. if I start on the wrong side homing will fail
same for X but the 'wrong side' is very short
I could home to the outer limit switches except then I would not be able to hardwire them to the amp disables.
move the home switch
so I have to make some tradeoffs, or redo some hardware
it is very hard to do that on Z - the prox is in a hole in the main casting
I will figure something out. it will be easy to make it work 'ok'
jepler suggests we could have ping-pong homing -- if on the wrong side of the home switch, bounce off the limit and home the other direction -- I think/hope he was kidding.
not a bad idea
if you hit the limit before the home switch move the other direction until you see the home switch
then go past it, then home in the original way
but if limits don't disable the amps, you may as well home to the limit switch and have it much simpler
you would have to have amps with directional disable
true (these don't have it unfortunately)
that is a great feature
so far my amps have + disable and - disable connections
these have one 'inhibit' terminal
scratch the ping/pong home
both screws have allens on the free end! it was a very regular occurrence to get stuck on a limit I think. homing is very flaky as-is.
they recommended you always jog both axes "in" before homing so you would not be on the wrong side
the cinci has the X homing in the middle - you have to jog the cam past the switch in the negative direction before you home the machine
can you make a new cam that's half the table length?
with emc, you could fix it right, by doing that
yes I agree - I should have moved the cam and switch a long time ago
I could have done it right with OpenCNC
if it is slow I can see wanting to home in the middle - you just need a very long cam
the cam is in a slot on the underside of the table - very easy to move
the microswitch would be more difficult
ah, nice and simple
is the cinci running now?
I will check - I may be able to do it by just moving the switch - we are ready to reinstall the spindle again
I will not be in the shop tomorrow - maybe it will be together when I get back Monday
I'm anxious to see it
It is NOT possible for you to be any more anxious than I am :)
haha I bet
I think my teeth are almost worn down from gritting them
it has been a much longer project than you expected. I hope I have better luck on mine but I will not bet on it.
you don't have a shop full of old machines with old controls to eat up all the time
but I do :-)
not as big a shop but stuff is just as old!
yes - I can't wait to see your shop
it is getting full
we had a lighting strike very near the shop last week - it seems as if every control has a quirk now
we checked the ground potential on the incoming service - we got 0.8 volts - it should be 0.0
we looked outside on the switch gear - the ground wires on every pole have been removed - copper thieves are unbelievable here
they are just asking to be killed doing that
I will call the power company but I don't expect much response - the thieves have hit all over town
I saw on the news - not in Wichita - someone had climbed a pole to harvest wire - 7200 volts got him
should I feel guilty if that doesn't make me very sad?
john k says people in cleveland are going around to abandoned (repo'd) homes and tearing out all the plumbing and leaving them to flood
essentially destroying the houses
it is sad but I don't feel very guilty - the darwin awards will maybe pick that up for an award
the copper thieves are doing that here also - sometimes someone will come home and their AC will not work - the unit has been stripped during the day - wow
you'd think that can't be the easiest way to 'make a living'
this isn't a living - it is for drugs - these people work harder at not working than if the got a job
bbl - I am trying something with brlcad
they should just switch to aluminum
stustev: here they steal the copper overhead cables from the electric trains. And with a few kV it sometimes DOES go wrong :-D
Sweet, found a workshop that has all the tools & parts i'll need to make a CNC machine :) he said he MIGHT have some steppers laying about, so all i need now is the stepper controller :p
which brings me to a lil' question, would i go for bearings, or make plastic guide bushings that slide over the pipes
pipes? solid bars I hope
* archivist_ub looking for mass, strength and stiffness but not in that order
actually it's a pretty thick diameter and short distance, so pipes would suffice
thick walls, keeps the weight down and doesn't make that much of a difference in stiffness
what accuracy are you looking for
.5mm would already be nice for a first one, more is a plus
ok pipes should achieve that
esp. pipes with a diameter of 30m >.>
i'd grab my calculator and tell you exactly how much it'd flex but i can't find it :p
remember how cheap pipe is made and what specs they dont care about
who said "cheap pipe"
cheap pipes have a weld running along the length, which i don't want
others are extruded
Anyways, pipes of full rods,.. bearings or bushings ;)
so are not straight if they sag out of the die hot
bearings/bushings is friction v cost
and simplicity of design
both about the same unless there is added play reduction
well bushings can just pe pressed into the MDF, for bearings i need to cut 2 strips to fit the L profile in, with 4 bearings on that, who'm are all 4 perfectly aligned
just wondering if theres a big advantage of the bearings system over the bushings, thats all
could design for very low friction and 0 play with bearings
true.. bushings would be a balance between perfect fit, and friction..
bearings it is! :)
with bearings you can have one side fixed and strong springs the other
as long as springs are above cutting forces seen by the springs
and track is straight and smooth enough that steppers can push bearings against springs during moves
"I god had meant us to us the metric system, we would have been born with ten fingers" .. now you may call me a liar, but the last time I checked, I have 10 fingers and 10 toes...
8 fingers, two thumbs ....
the thumb is also a finger afaik
is it possible to use emc with a cnc-milling machine connected to a serial port (ttyS0)
lyll, doesnt make sense as emc is designed to have full control although I have seen the odd request
i have a small milling machine that only havs a serial port for comunication
an older version of this: http://www.max-computer.de/x5e/small_format_a5a3.html
so there is no way to use this wirh emc?
probably with some modification depends on your skill level
it won't be "plug & play" -- you would have to have full knowledge of the serial port communication, and figure out for yourself how to make that fit with the way emc works.
lyll, if it has get at able stepper drivers internally, adapt and connect to the parport via optos
yes, getting direct access to the steppers or servos is another option
* lyll has no parallel ports :(
you could obtain a PCI parallel port or a smarter PCI card like those from mesanet.com
ill try to adapt it.. thx for the information
someone here most of the time to answer questions, american timezone is best though
jeez the chineese are CRAZY.. did you guys see the opening ceremony?
it's like O.O
hi all, I have a little problem... stupid enough. I registered to the emc-user mailing list and I keep receiving all the post in my mailbox. Where can I change the option to not receive all the post in my mail box?
I checked the website, but I only find the subscibe section...
do you mean you want to unsubscribe?
no, just don't receive all the post
do you mean you want to receive a digest instead of separate messages?
I'm having trouble understanding what you want, because to subscribe to a list generally means you want to receive the messages
how does the digest present itself, an archive?
once I wanted to post a question... but now
if you follow the last URL at the bottom of every message, you can enter your email address there and edit your preferences
cool, thanks, I'll check now
follow the URL that's after any advertising that gets added
It is not that messages from others don't interest me, its just most of the time, I am of no help...
I keep deleting them to make room in my mail box.
use gmail its free and they allow gigabytes
no need to delete then
Thanks, but personaly, when I have gigs of stuff lost around, I feel like my whole life is a mess.
Thats fine, I found how to edit my profile.
Thanks to all. ciao
instead of using a market, I just used tipp-ex to point out an important part of my coursebook >.>
I need some ideas.... I'm getting a digital datasafe w/o the combo. So I need to come up with a "device" that can punch the buttons for me and pull in the handle. any suggetions on solenoids? need 12 of them (but cheap)
cheap solenoids.. o.0
this is EMC, here you use 2 steppers and a solenoid
3 steppers! no solenoid
if you always hav eto do the same distance, there is no point in having 3 steppers
too much added complexity
real men would hook the solenoid up to the water pump function
actually a 4th needed to test open the door
why not just weld a big bolt onto the door, and screw a hydraulic press onto that?
or a water jet
* archivist_ub imagines it wont need that much effort
I can get into the safe anytime I want, but this is a data safe, I want to maintain the integrity
"w/o the combo"? is this just to not leave fingerprints? ;)
tomp: say that again?
"w/o the combo"? is this just to not leave fingerprints? ;) ;)
Well, found the cheap part... just not mountable http://www.electronicsurplus.com/ccp73696-6vdc-solenoids-intermittant-duty-small-a420-066410-00-7678.htm
tomp: I meant rephrase it =)
it sounds like you didnt want to touch it , explaining jokes is useless
ah, they don't know the combination to the safe,
this has potential... http://www.electronicsurplus.com/objects/catalog/product/image/img73691.jpg
if you don't want to touch it, use a breadstick >.>
so, encoder and mesa card all wired up ...
im single ended on the encoder, but the mesa is diff in,
hm.. then you are fscked :/
I presume I just ground the /A and /B inputs?
(unless your mesa can do either)
what mesa board?
well, assuming its just a diff amp ..
conversion to diff is also possible
but i ouwl have thought not needed
surely just grounding the /A and /B inputs will do it?
is that 7i37?
but that's just the isolator board
it dosent have a encoder input
thnaks for playing
what's your other mesa board?
they can do ttl also..
page 5 of the datasheet..
but I need to ground the spare input
no, I dont think that matters
in that case it should work ;)
* robin_sz scratches his head
robin_sz: which board? 7i30? 7i33?
differential pins are other inputs no?
* archivist_ub might expect to set it at mid rail not gnd
then ignore them..
it dosent make sense for it to take both the differential and the normal one in consideration..
so in TTL mode it just uses the A and B pins
not after you've set what you want to care about..
in diff mode it uses the A and /A, B and /B
yes I'm pretty sure that you do not connec the /ENCA and /ENCB pins when you use the TTL jumper setting
* anonimasu_ nods
might need a harder pull-up resistor then
hm.. why do you need a pull up?
dosent it work for you?
open collector outputs on encoder?
some encoders are open collector
i was expecting the 'joint' to display the position when I moved it by hand
even in estop
do you have a scope to check levels on that pin
twiddling the axis by hand does not seem to register in emc
yes, I do
I'm 100% sure that in "machine off" state, emc tracks encoder inputs to display on the DRO. I'm 99% sure that it also does in estop.
it would make sense for it to track them always
yes I agree
so I added astronger pullup
microstep or halfstep?
I hav 200 ohms now
(which should i program into my PIC)µ
and about 2.5v square wave
should be enough
fragalot: what task is your PIC performing?
the mesa has IO 1-24, 25-48, 49-72
how do Iknow which ribbon cabel is servos , which is limit switches?
jepler: converting step & direction inputs to stepper output
also, does EMC step on the down or up flank of a step signal
robin_sz: "P2" is encoder/dac 0 through 4. see http://linuxcnc.org/docs/html/hal_drivers.html#r1_5_4
ok, im using P2
fragalot: stepgen uses a TRUE pulse on the step output for a step, but you can invert the outputs that appear on the parport or other digital output if your device requires it different
im assuming they come out as per the Mesa manual once they have gone through the 7i33
jepler: so it steps on the rising flank of the true pulse
jepler: he could also get stepper outputs direct from EMC, without the step/direction conversion too
or could once anyway, I assume we stil lcna do that
jepler: so, microstepping or halfstep for the steppers ?
I use halfstep, I dont expect great speed from them
fragalot: yeah, half step will be easier to implement and it's perfectly adequate for a small mill
you don't get much more positional accuracy from microstepping
no, but it might have had another benefit
fragalot, reduced resonance, so easier to accelerate though the critical speed
IMO look at l297 for an idea of what a good half-step translator & constant current controller will do. when I looked at doing something like that in a microcontroller (I considered AVR rather than PIC) the main barrier was having two analog comparators or DACs that were fast enough to give good chopping performance like l297.
jepler: doing so right now
er, not DACs but ADCs
yup they do the current limiting for you
I'm also looking at alternatives to the µC
like dedicated circuits, such as the l297
I would use dedicated or bought in
how is this
[18:57:49] <fragalot> http://www.pchilton.co.uk/images/stepperdriver.jpg
or this one.
$26 .. can't really go wrong on the first one (premade!)
well, coinfusing, I have nice 3V square waves going into the 7i33
0 to 3v,
pleanty for TTL
jumpers in TTL posiotion
7i33 connected to P2 of the 5i20
now is it a good time to start with the goats blos and chicken bones?
it has to be polarbear blood. for it to be of any use
fragalot: schematic_th.gif looks like a pretty typical L297+L298 board for bipolar motors.
so difficult to get polarbear blood
robin_sz: transfer it to connector P3 and use halscope/halmeter/whatever to see whether looking at those signals as digital inputs you see any changing input values
opening the PC again ...
moving the monitors again
oh welll ...
ah wait, I havbe a cable ready for P3 .. woo hoo
jepler: cool, I found it for $26, looks like it's a reasonable price (and i don't have to do any design work ^_^ yay)
fragalot: oh, the maximum current for L298 is 2A
make sure that's appropriate for your motors
robin: what did you change?
he switched it on
not a thing
jepler: 2A is /MORE/ than enough for me.
i read the PDF
and it worked
is it linked?
robin: ah so documentation is useful
fragalot: and your motor is capable of bipolar operation? (4, 6, or 8 wires)
just figuring out which transformer i'll need to get 240->24VAC (eg. how much amps it 'l all pull)
fragalot: beware -- their design is limited to 30VDC by the capacitor C3's voltage rating. 24VAC rectified is more like 34V.
I got lucky and have a 28volt switchmode psu which adjusted to 30v nicely
18V it is
L298 is good to 40V+ but C3 isn't
jepler: C3 is easilly replaced..
hm and 1N5822 is limited to 40V
c3 on diag is 35v
archivist_ub: voltage spikes occur.
owell, i'll just use an 18V toroid
electrolytics run close to voltage
unlike other devices
just figuring out which VA i'll require (could do "as big as i can find", but tahts expensive :p
archivist_ub: yeah but that doesn't leave any margin or allow for V+ to rise due to back EMF
switchmode sucks for cnc
working fine for me
mm, 18V 160VA -> 48euro
and a big capacitor.
and badass rectifier.. ... meh i'll just make one with the pile of 6A6 diodes i have laying arround
switchmodes work too.. it's just that if you have back emf.. they usually shut down :)
huh I haven't seen that problem
in my piddly little machine the switchmode supply works fine so far
Im using a Coutant Lambda one not a chinese cheapo
but ask me again after 1000 hours of use
it might just be the one I used in my app..
thats the encoder hooked up and scaled easy peasy
it was a DC to DC converter..
anonimasu_, maybe an extra bit of decoupling was needed
i guess an input scale of 100 is a bit coarse
robin_sz: / mm?
sounds good to me :)
now, 160VA is just overkill (i hope 3 stepper motors of 1A ), but who cares. -> how big of a capacitor would i put on :p
yeah, mm is hte only way
finished installing a new bot today :)
has it killed anyone yet?
nope .. not a rogue one :)
give it time
it's a mid-sized one .. so definately the power is there
yes for sure
~ 9m long
that is envelope?
or track length?
9m linear track
suggests C=80000*I/V where I is current and V is supply voltage
then the robot
and 2 positioners
jepler: sweet, thanks
fragalot: in uF
one for 5t parts, one for 2t parts (lathe type)
fragalot, you could just buy geckos, will be cheaper
robin_sz: the next one (I start working on on monday) is 15m long
but the big one is ~20m long
robin_sz: do geckos take 240V in? (and last time i checked, a single gecko starts off at a higher price than 3 of these other circuits)
fragalot: a gecko will outperform it for sure.. too :)
of course they dotn take 240v in, neither does an L297, and 3 geckos costs lots less than building 3 1A drives
fragalot: no, they take 48v in max..
anonimasu_: i'm not after performance that badly ;)
robin_sz: actually,.. no
robin_sz: sent you a pic :)
fragalot: robin_sz counts the labour time too
robin_sz: atm one stepper driver costs $26, the coil i just found in one of my catalogs costs $35, the rectifiers, just diodes that i have laying arround, capacitors, i have laying arround,...
we cheapskates dont
alex_joni: I like a bit of work :)
besides, it's just for in my spare time
fragalot: if you can spare the time :)
beats beeing on IRC
* alex_joni just got home..
and it's 10PM :(
fragalot, well, weve only been on this channel 6 or 7 years, and, as yet, weve seen a few hundred people try to build their own drives because it was "cheaper" .. as yet, none have saved money, most have not succeded, and most have bought geckos in the end anyway, but, feel free to prove us wrong.
robin_sz: I have 2 geckos and one 297/298 on my machine :P
heh, i had 207s as well
I didn't quite build it myself, I had one of my employees do it :D
horrible things :)
robin_sz: it's a kit with the 297/298 combo on it
fragalot: well.. in the end I ended up debugging/tuning it until it ran
alex_joni, i started out with L297, but they are pretty bad
I hate FANUC.. I really REALLY hate them machines
if it runs, and it runs without stalling, i'm happy
robin_sz: I built four L297/8 driver boards and am still using them. geckos are awfully expensive.
fragalot: an L297/298 is quite more than 2-3 chips on a board
you still need to tune current limits, and so on
alex_joni: don't call that debugging, call that finetuning.
and my experience is that xylotex also works quite reliably, though I'm not using it near the current or voltage limits
I also considered the hobbyCNC board
I can surely feel quite a difference from the geckos to the 297/298
cradek, ive run both, the geckos make the 297s look like .. well, a ferrari compared to a trabant. the performance is so different, it makes the 297s look broken,
but I didn't justify it yet to buy another gecko for the Z axis too
all in all, i think the price will be relatively the same, and if it breaks, in this case by using 3 seperate drivers, i can replace the one that broke instead of the entire board
robin_sz: won't argue on that
but I have tiny steppers.. so it doesn't really matter
hm.. also geckos dont break..
except mine.. :p
as the steppper get bigger, it matters
dont run them without current limit set.
anonimasu_: I also have some 201's
those break easily :)
hm.. I dont think so
anonimasu_: that's what they say about FANUC drives too... guess what, wher eI work, those are the most common things that break. the cheap taiwaneese relay-based boards hardly ever break.. sofar had to replace 2 relays,.. in total, on 7 machines
I mean obviously you cant run them without motors..
ive had a bridgeport running on 201s :)
anonimasu_: oh, and their PSU's, but thats because they underpowered it :p
I had a duff driver from my source (seems an intermittant)
so, now to hook up the analogue out :)
and pray I get it the right polarity :)
test them first..
comanded poitin at zero
move axis to +10
will the bits fly this far north? should I duck
robin_sz: you hooked up estop already right?
and tested it to work?
jepler, what is the "estop" of which you speak, is it a custom amongst your people?
robin_sz: yes. it is the custom among my people that once you've pressed a woman's estop button, you are married to her.
better be careful with thoose rapids
robin_sz: I was just letting you know that all of "as yet, none have saved money, most have not succeded, and most have bought geckos in the end anyway" did not apply in my case
* alex_joni hates safety regulations
cradek: well, you are special :p
things get more and more extreme these days
first they started using double contacts on all safety switches and estops
now you need additional PLC's connected to limit switches and workcell selection
my lathe has some air powered stuff, like a special slide for a parting tool. I am trying to figure out what it should do during estop.
for the stuff I'm talking about you actually feed the axis position into a PLC
then you teach it the location fo the switches
and if it reaches the switch position without tripping the switch it estops the whole machine
(it assumes the switch is broken)
i need a new programmer for a new technician, i do PICs PEELS 8051's not too fancy. I used to use Needham's. they're outta bizness. Any suggestions?
We typically have our technicians pre-programmed by their parents. :-)
lol @ ken
I use one of Microchips own for PIC
usually genetically programmed ?
outta business (Needhams & Grandparents;)
archivist yes, got that with PicLab, but these guys wanta swiss army knife that does everything
tomp my other one is also an out of business one :(
anonimasu_: I know..
alex_joni: why not rely on a linear resistive encoder anyway..
whenever something changes, you need to reteach everything.. it's .. &^*(&(& to say the least
alex_joni: if it breaks you know it's broken..
anonimasu_: this is for workspace separation
hm.. like robot cells?
if you have 2-3 work places along the same linear track for example
but it can also be 2 tables left and right of a robot
alex_joni: thanks, thats pretty much the items i burn, so how much is a Brutto?
brutto is the price with taxes
ooops, is the unit Euro then?
zlotny = half a buck
1 Polish zloty = 0.460723 U.S. dollars
not really cheap, but acceptable
holy crap.. zloty better then sek -_-
uh no :p
1 Swedish krona = 0.33671313 Polish zloty
well.. two of the people I worked with from sweden, were actually polish
heh, trying to find a Linux compatible device programmer, so i dont have to boot M$ to show these guys
wow, that Polish unit is the least expensive i've found
i've seen/alex found
tomp: it was the first google hit
* alex_joni heads to bed.. been a long week
and it's not over yet
anonimasu_: geez why can't everyone just use metric?
how many mm in one zloty?
everyone does use metric
no we dont
well not all the time
* archivist_ub hugs the mm/in button on the guessing stick
can't say weve got anyting that works in inches ...
I have imperial jobs on metric machines and metric on imperial
we just dotn see imperial jobs at all really
a few, very few, enquiries
but we tend to decline them
we do restoration work, so see old stuff
you just know if its in inches they wont have electronic drawings ...
drawings!!!!, I get worn parts no drawings
heh, we run a mile at that point
make it fit
oh never mind
send them here, we need more work
farmers are the worst
"can you make someting to medn thei bag of rust?"
"no, not the whole thing, just this bit, dont want to spend more than I have to"
dont damage the twine holding it together
its easier to just send them on their way
my favourite is "im sorry, we dont do welding" ..
always funny as there are 6 welding bays behind me with bright blue light coming out of each one
production welding and repair welding are in a different world
repair welding is best left to guys in garages
I did production welding for a while
its a different skill
our guys are all coded
perfect welds first time everytime
you see them do a 2m long run sometimes in one hit
yes have done own car repair, chasing paper
thats a long run
we had machines for long runs
best on watertight work to not stop and start
has to be dye-pen tested afterwards
mmm ... coolant tanks and chip conveyor systems
we have a couple of small clients ;)
My router is (finally!) all wired up and working. I need to make a cutting table, now, and am considering a few pieces of angle iron running the lenth, with a sheet of MDF bolted to it. Any opinions?
I originally had a plywood table 1/2" thick, and about 1' between the supported ends. I found it was too uneven and flexed too much for trace isolation milling, but it would probably be OK for many other tasks. I replaced it with an aluminum table, also 1/2" thick and it's much better.
obviously flexing/bowing will increase with the distance between supported points
owad: so, how big is your machine?
work area is 2' x 4'
and what level of accuracy are you aiming for? router work, +/- 0.010" or so? or PC and milling, 0.002" or better?
jepler: yeah, that's why I was thinking about the angle iron underneath\
right now, just router work. Eventually I want to get better leadscrews and nuts and try some fancier stuff, but not yet
holding 0.002" over a 2' x 4' table with anything other than serious amounts of steel would be tough, so thats a wise decision
that'd be an awfully large circuit board :-)
jepler: what sort of table do you have now?
owad: aluminum 1/2"
[20:51:27] <jepler> http://axis.unpy.net/files/01215190154/table-medium.jpg
note that is work area is about 1' x 1' (maybe a bit longer and narrower)
good point ( whatever 'beam deflection' is for a plate )
angle iron is far from the stiffest possible shape
just ordinary bolts, typically, to hold the work down?
square tube or I-beam shapes will be stiffer
ok, I'll see if I can find that affordably
what is the frame of your machine made from?
all of it?
what is the stuff zen-bot was made of?
[20:55:26] <owad> http://tinyurl.com/5ahdnm
owad: so the X rails are on "I-beams" made of MDF?
the table has to go over the top of that crosspiece, right?
the table will have to be about 6' long, to fit over the machine
and the crosspiece moves with the gantry, so the table can only be supported from the ends
tomp: the white plastic is HDPE if my old blog entry can be trusted
to use MDF alone, you'd need two "I-beam" structures at least as tall as the ones holding the Y rails up
stand it up so gravity doesnt bow the 6' ft table
which obviously won't work
MDF on top of steel square tube?
how much height do you have to work with?
a good bit -- let me measure
(total height of table and sub-structure/frame
I'm not seeing that much
from the ridge across the back of that crosspiece up to the tool is maybe 8"?
I assume you want at least half of that for the workpiece and tooling
a 6' long piece of 2" wide x 3" tall x 1/8" wall steel tube is $40.72 from metal express, weighs 22 lbs
two of those running lengthwise would be a start, although you'd have sag inbetween
maybe thats where you use the angle iron or smaller square tube
for the long support members, taller is better (stiffer), they also have 2" x 4"
both are available in a variety of wall thicknesses
4" for the permanent table (from the farthest the tool will extend down, to the top of the under carraige)
did you do all the MDF cutting or was it a kit or something>?
so you don't have the tools to cut say 6' long 3" wide strips of MDF from a 4'x8' sheet?
yes, I can do that. I have a table saw
you might consider cutting a bunch (maybe 10) 3" wide strips, then gluing them on edge to the underside of another sheet of MDF
10 strips spaced 2.4" apart running lengthwise will provide reasonalby good rigidity in that direction
you'd recommend that over angle iron? I guess that'd be cheaper
adding another thinner sheet on the bottom would make it even stiffer
I'm not recommending one over the other
it depends on what you can work with, etc
for example, if you can weld, I'm sure you can make a much stronger table out of steel tube, and just add an MDF top
but if you don't have a welder, that gets hard to do
I can trill, tap, and bolt, though
I have no idea what MDF costs
does it glue well? is that thing glued and screwed, or just screwed together?
wood screws (self tapping) or thru-bolts with nuts?
screwed, with cross dowels
how thick is the MDF?
when I use wood screws, it tends to split
ah, that would be a problem
I was thinking of a top surface made of 3/4" MDF
on the bottom of that sheet, route 3/4" wide x 1/8 to 1/4 deep grooves the long way, about 8-10 of them
glue 3" wide, 3/4" thick strips into the slots as ribs
then if you can get say 3/8" MDF, route 1/8" deep grooves in that, and glue it to the ribs as a bottom sheet
that sounds pretty sturdy
result is a 4" thick "slab" that is sort of like corrugated cardboard
and then fill it with sand :)
as far as mounting things to the table -- just drill holes in it, or is there a cheap way to do something approachign T-slots?
fenn: one nice thing about MDF is that it is well damped compared to steel
owad: I think I've seen an aluminum extrusion that was intended to be set into slots in MDF to make a t-slot
personally I can't get too excited about that, but I'm a mill/metalcutting guy
might be OK for wood
think woodcraft sells those
hmm, can you get thinner MDF? like 1/2 or 3/8?
the ribs don't have to be 3/4" thick, the strength comes from their height - if the ribs _and_ the bottom were 3/8" thick, it would be lighter
found it. T-Track: http://www.woodcraft.com/family.aspx?familyid=3782
the top needs to be thick of course
I'm not sure what thicknesses I can get
that t-slot stuff needs a slot over a half-inch deep
what about plywood?
2/3 of the way thru your top - that would suck
plywood for the top would suck unless it is very high-grade ply
if you ran the ribs the other way it wouldn't really matter
I suppose you could use it on the bottom and for the ribs
the ribs need to run lengthwise - the table is only supported at the ends
you could run the t-slots crosswise I suppose
looking at those t-slot extrusions, I'm about 99% sure they are NOT designed for clamping stuff down
I suppose they could work if you drilled them every 6" or so, countersunk them, and screwed them down
have to be very carefull using traditional clamping approaches tho - normal metalworking strap clamps pull up on the t-nuts and push down on the work and the step block, neither of which will be on top of the track
the clamps they make for that track push down directly on the lips of the track, so they aren't trying to rip the track out of the table
ok, I'm going to go to the hardware store and see what I can find
owad - just a sec
I really appreciate the help!
go to mcmaster.com, and look at page 3211 in the catalog
they have 1/4-20 threaded inserts that screw into drilled holes in particleboard (and probably MDF)
100 inserts for $12.51
you could drill a grid of holes and run them in with an electric drill
as a matter of fact, I already even have some of those
or just get the ones you pound in from the back
a 2" x 2" grid over a 24" x 48" table would take 288 of them
haven't tried them in MDF, but they work great in wood
you could probably use the machine to drill the holes for you ;-)
that's the only way they'd end up in a straight line :-)
I'd be reluctant to use the ones you pound in from the back
fwiw a 24 oz bottle of upsidedownium lets it sit above a simple static work table http://imagebin.org/index.php?page=add
my experience is that the prongs are not very sharp, and rather wedge shaped
in wood they're OK, but in particleboard or MDF, they displace material and cause crumbling or cracking - not very strong
ah but having a full flange is better then thread forming stuff onto MDF
maybe - the ones I was looking at have "knife threads", not 60 degree threads
still threads in MDF just sounds scary
I much rather drill oversize and embed in epoxy
I've seen the back-insert ones that had a round flange with holes for small nails (brads) - those might work nicely
the formed metal prongs scare me tho
in any case, I'd start with a scrap of MDF and several candidates, and try them, before buying nearly 300 pieces of anything
hahaha, unless you are doing a first article for production, then 300 peices ain't too bad ;)
this is for hold-down holes on a router table - the 288 pieces _are_ the production run
now if you were manufacturing router tables....
I've got plenty of scrap, so I'll give it all a try
owad: I think threaded inserts will cost less and probably be stronger than the track thing
the track is definitley out
I'm concerned the threaded inserts will split the table, but we'll find out with some scrap pieces
of these MDF, nylon slab, plexiglass, or HDPE/UHMW - which one am I likely to find the cheapest for a 6x8x0.375 sheet?
MDF by far I suspect
6 x 8 feet?
making a base to display a circuit board
in that case, you won't be able to buy MDF that small
plexi cut offs used to be cheap but they are going up in price
Lowes sells 2'x4' sheets and they cut it free, though
6x6x3/8 nylon at mcmaster is $9.40
HDPE/UHMW is basically a cutting board if I can find them cheap
owad: the local Lowe's panel saw is perpetually broken :(
* robin_sz prepares to fire up the servo drive
12x12 is $27
I'm off to the hardware store. Thanks for the help, jmkasunich.
Thanks jepler, ds2, fenn.
McMaster needs shipping unfortunately :(
12x12 acrylic (plexiglass) is more - $44
guess I am back to pondering a way to make this cheaper
I can get 12x12 locally for $20 cut rounded off
trying to see if I can do it for sub $5
ah, that will rule out most plastics, unless you can get creative - like actually using a cutting board
you only need the one piece, right?
yep, one time thing
has to be 3/8" thick?
needs to be hard enough that a 4-40 nut won't dent it
nope, 1/4-1/2 is all good
even 0.75 if it is cheap enough, but that's starting to get heavy and would complicate getting 4-40 fasteners long enough
what about thinner?
I don't want to go below 1/4 as it would flex too much as a display panel
gotta be 8" long?
nope, that's flexible too
I think 6x6 might work if I am careful with the board placement
mcmaster has 6x6x1/2" ABS plastic, beige color, $6.11
they have 12x12 too, but that is 4x the square inches, 4x the price
* ds2 looks
still over my target price but it is getting close
they have a lot of things in 6x6 that aren't too pricy, but as soon as you go to 12x12 it gets high
ABS is probably among the cheapest
I really would like to get it under $5... it is partially a volunteer effort
6x6x1/2 PVC, gray, $5.54
but as you say, shipping is significant on small orders like this
well, there is shipping on top of them
is there anything common like a cutting board that would be a minisheet ?
if shipping is an issue, we really can't help you - you gotta go to a local store/supplier and see what they have
I was more of looking for suggestions as to things that are flat and roughly that dimension that I can cut up
cutting boards, plastic storm windows
(dunno if clear is OK)
plastic storm windows? /me googles
I got a can of white spray paint!
why not wood?
you cant cut spray cans!
think of the mess!
grain I think would be objectionable asthetically
robin_sz: that's what water jet is for ;)
* robin_sz adds that to his list
i looked at one this year
but decided agaisnt it
bought a 2nd laser instead
i wish i had a laser
a little 10watter would suffice
ds2: did you say you have a waterjet?
ds2: mine are 2kw ish
unless you count a water piston used to cut patterns in dry sand ;)
waterjets are f-expensive.
yeah, and waterjet is slow
* jmkasunich looks at 12x12 solid white ceramic floor tile - home depot, $1.09
but well, waterjets cut alot of stuff lasers dont :)
the one I looked at as a 4.5axis
robin_sz: different applications... I am happy just to mark stuff
laser cuts ceramic tile ok
he doesn't have a laser either
lets club together and buy him onw
ds2: would 12x12 be too big to use as-is?
jmkasunich: yeah, I need to fit it in a box that gets carried on public transportation
I do have a tile saw... Hmmmm
oh, they have 6x6 ones too
just make sure it includes a lantern battery, some wire, a short length of boomstick, and an alarm clock.
sub it out for waterjet if you have to
that's always welcome on public transportation :-)
robin_sz: did you miss the part where this is a charity job with a target price of $5 or less
ds2: I'd say, get thee to the nearest home depot or similar and look around with an open mind
Multiple layers of thin cardboard, glue, varnish. Make your own plywood.
the 6x6 tiles are $0.42 each
jmkaunich: the killer there is I don't have suitable diamond/carbide drills for the screw holes... regardless, I am planning to visit several dollar stores this weekend
could you glue instead of screwing?
bath tub caulk should stick PCB to tile
no, the PCB needs to come off
I have a mcmaster catalog here. Glue a bunch of pages together with the front and rear covers, and you should be all set.
hahah a used mcmaster catalog is worth more then $5!
I can probally sell that, buy lunch AND some new materials and pay for someone to do it :)
Will aluminum work? I could mail you a 6x8 piece of aluminum sheet.
and still ahve change
what about tempered hardboard, aka masonite
hardboard is good, just need to find drops/cut off sources
$7.88 for a full 4x8 sheet, I think they may sell half and quarter sheets
Damn, with all the time we've wasted discussing this, we could all chip in and buy you a block of gold to bolt this too.
anyways, thanks for the ideas
well, if any of us was getting paid for that time
that bolt this 'to'
you're welcome, and good luck
figure it can't hurt to get ideas off other scrongers ;)
the problem with asking scroungers is that we don't know what is in your junkpile
I just cut a front panel with 1/8" hardboard
(I could probably find a piece of 6x8 lexan or similar in my junkpile)
I go into dollar stores with the idea that everything is raw materials for other projects
can I ask a quick question?
you just did.
we'll allow you to ask another one though
ok, the 2nd question is where is the filter for for file extensions? I want to ad .nc to the NC file open in axis
Look in the .ini file.
i did it has the directory info and the documetation says filters for porcessing
i.e. graphics to ...
It should be self explanatory to add another one.
I think he's actually asking another question
not "how do I run a file thru a filter", but "how do I make the file-open dialog display files with .nc extensions in additon to .ngc"
Yup. He wants .nc to look like ngc.
I suppose you could try "cat" as a filter for .nc
i want to see .nc, .ngc .tap files
I don't know how to change the settings for the file open dialog
axis has the ability to use external programs as filters in the unix sense (stuff a file in one end, and a modified file comes out the other) which is what I initially thought you were asking about
no, I found that in the documentation but it just the load dialog
you can specify filters for various extensions - "if the user opens a .foo file, run it thru filter bar"
John, I think your 'cat' solution will work.
if you have defined a filter for .nc does that make .nc appear in the file open dialog?
if it doesn, then you can define "cat" as the filter for .nc
yes. I believe so.
I didn't try it as I assumed it would want the following lines to tell it what to invoke
have it invoke cat (which simply echos the original file with no changes)
I thought it was a quick question, sorry
See the function open_file in axis.py. It adds some extensions to the tuple 'all_extensions'.
As an alternative, just change that function to create the tuple containing ".ngc" and ".nc".
what directory path
I wouldn't be surprised if you just add the extension to PROGRAM_EXTENSION in the ini file and did NOT at a line nc = cat, if it did just what you want.
ok I'll go try some things thanks
Looking at the source, just add the PROGRAM_EXTENSIONS = .nc line and try it. Should work.
fyi adding a [FILTER] section and a PROGRAM_EXTENSIONS = .nc didn't work it recognized PRGROGAM_EXTENSIONS i think because if I changed to PROGRAM_EXTENSION got all kinds of error messages
* robin giggles
strange .. when I connect the drive and tie enable high .. the motor oscilates about 20mm +- on the slide
even without the +-10 signal connected
archivist is now known as archivist_emc
archivist_emc is now known as archivist
archivist_ub is now known as archivist_emc
archivist_emc is now known as archivist_ub
ds2: go to a sign maker's shop and ask for any cutoffs/trash, or failing that a cabinet maker
the problem with scrounging is that just a little bit of junk isn't enough, you need a whole pile for it to be useful
and once people know you are a repository of old junk...... it keeps coming
i think this DC drive amp must have some additional crap in it
for armature feedback or some such
its got various contants that can be set
surely with PID in EMC, I dont need anyting else on the drive do I?
I forgot about sign makers