anybody got some sort of idea for how much spindle encoder resolution is necessary to do rigid tapping?
i'm about to order a 100ppr, but not sure if that will be enough or not
for a m10x1.0 thread, it would be 1.0mm per revolution, so the accuracy should be good for .01mm, which seems like it should be adequate
as long as there's no weirdness that happens with acceleration
is that 400 edges or 100 edges per rev?
what will be counting it?
servo thread i presume
the quadrature-reading part of the software encoder module runs in the base thread
software encoder? is that what reads phases from the parport
it says "100 pulses per revolution"
so i guess it would be 400 edges like you said
a rising and a falling on each
[04:11:47] <cradek> http://www.linuxcnc.org/docs/devel/html/man/man9/encoder.9.html
hey 10 khz isn't bad for software
almost all modern machines can do 50kHz
well thats good then
because my spindle goes faster than 500 rpm
it only has to keep count when tapping - who cares the rest of the time
(unless you want to use it for an rpm readout or at-speed sensing)
i would like to use it to make sure i get to the right speed to
but an index pulse may be good enough for that
that definitely limits your resolution
you will miss the index pulse just as easily as you miss the other counts, if it's going too fast - nothing is there to 'stretch' it
all i have on there is an index pulse right now
i was threading at 500rpm with it, but it was pretty jerky
i wonder if some of that might be it missing an index pulse
that would sure mess it up
i take 10 passes to get the thread to full depth, and about two out of every pass winds up being nasty
if i'm lucky its one of the first ones, and the later ones cover it up
if i'm unlucky then it tears up the thread and happens on one of the later passes
i.e. scrap part
so i've just been running them to about half depth, and finishing with a die
but i'm still curious why its so jerky
running slower didn't seem to help it any, and faster gets the accelerations too high to clear the blind corner at the end
I bet with a little study halscope will tell you
at first i thought my spindle belt was maybe slipping
the index is directly on the spindle right?
but if the belt slipped, then the axis wouldn't know it until it was already too far along
ok, heh, I was picturing it on the other end of a V belt or something
but that's not the behavior i'm seeing... its like the axis falls behind some how
does seem like that could be a missing pulse
if it missed a pulse, the axis would get ahead though right
no, it would thought the spindle just slowed WAY down, so it would slow the axis WAY down
setp hm2_5i20.0.encoder.03.scale -400
looks like my spindle encoder is 400 edges (100 lines)
what are you reading it with?
lathe only goes to 3000ish rpm
mine runs to 2000
single belt drive, vfd into a cheap 3 phase motor
not inverter duty, but it hasn't overheated yet
also not drip proof or tefc, but it doesn't seem to mind getting coolant on it for whatever reason
well maybe tomorrow i can fire up halscope and get this thing to thread better
maybe i need a wider trigger on the spindle
i have a lot of trouble with halscope getting it to trigger right though
i get more done with my real scope
wow that mesa 5i20 is something else
i didn't realize how advanced fpga's had come on that type of hardware
Odd is now known as tim__
[#emc] "This is the #emc channel - talk related to the Enhanced Machine Controller and general machining. Website: http://www.linuxcnc.org/,
wiki at http://wiki.linuxcnc.org/"
humm, is there any page with sample files in gcode? ... that i could try out :)
[11:21:00] <archivist> http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?Example_G-Code_Programs
* alex_joni loves that page :D
* archivist misses the http part because xchat does not see it as a link
wtf, can i set scale in axis ?
cause i found a "half ball" sample, but its 0.9mm big :P
thanks for that one alex_joni:)
alex_joni, my bot uses that page !g nick words
so any way to set the scale in emc ? ... as the stuff i load becomes like 5mm big ... everything :/
MrSunshine_: you can use G20/G21 to scale it by 25.4 ;)
2.54 isnt it ?
number challenged are we?
ahh i was thinking cm :)
i dont get it, why does 2 engines become so hot i cant touch them while the 3rd stays cool :/
do you mean motors?
I suspect different current limit
and different heat sinking
no heat sinks on them .. exactly the same driver (no current limitations on the drivers so :P )
frame and machine constitute heatsink
could make it a casting project =)
tho thin fens arent to easy to cast :/
starting a movie business?
casting as in metal casting =)
a new robocop movie perhaps?
BJT-Work_ is now known as BJT-Work
I think it is a bad idea.... but I guess that is what the mach people need. ;)
skunkworks, interesting... I still dont understand why people use step/dir when quadrature is so much better.... never could convince Mariss to offer quad drives
wonder why that is?
skunkworks, his new cpld drives would make it easy
LawrenceG: supply and demand?
JymmmEMC, how is the wx down south?
bites, cold and damp
its cool here, but the sun is shining..... nice day.... supposed to snow on Sunday WTF? its march
LawrenceG: Take a number (4,345,213,596) and get in line... Now serving # 23
Early sun was out and had blue skies, now damper and grey skies.
JymmmEMC, fixed my HF radio this week.... it had leaky caps --- stinky
did you use baking soda?
no.... turns out leaky stuff is also basic.... but I didnt really want to put vinegar on the pcb.....
I never said vinegar, just baking soda
and clean up with denatured alcohol
well baking soda and a dab of water
baking soda would have worked as an abrasive, but not neutralize the corrosive gunk
it does on car batteries =)
baking soda is basic, leaky stuff is basic and vinegar and sulphuric acid are acidic
The electrolyte is usually boric acid or sodium borate in aqueous solution together with various sugars or ethylene glycol
so i'd just use water
thanks fenn.... I just used 95% ethyl alcohol and a lot of scrubbing with qtips
the board was still wired into the radio, so hard to do a full cleaning and flush
LawrenceG: You coulda just tossed it in the dishwasher or washing machine, then tumble dry. Eeeeesh.
heloo go afthernon
my name is rafa
iam from brazil
i have one doubt
is possible on a Frequency Inverter in emc
is possible emc control this?
of cource, but depends on input to it how you need to talk to it
you have a idea about this?
how do you need to command it
i want on this in my spindle
when i try to load the calibration window in axis i have this problem. if i set setp hm2_[HOSTMOT2](BOARD).0.encoder.00.scale [AXIS_0]INPUT_SCALE in the hal file, i get this error > http://pastebin.ca/1354743
if i set it to a value say 1000 loads fine
rob__: are you sure it's INPUT_SCALE in the ini? not SCALE ?
hmm.. it seems to be INPUT_SCALE, n/m me :)
i was just checkin, yea input_scale set to 1000 and it counts incoder fine in proper scale and axis loads no errors only when i go to calibration
rob__: it looks like emccalib can't handle the case where the thing being set has a substitution
if you write a literal number like 1000 then emccalib doesn't try to do anything with that line (I think)
when i change it to number yea it does not complaine about it
oh well no biggie ill put in my proper values in hal, throught be nice to leave it in ini file so if i ever changed them id not forget
I am pretty sure there's not an easy fix to emccalib for this
your other choice, it seems to me, is to replace [HOSTMOT2](BOARD) with the name of your board
in your hal file
ill see if tht works thx
seb_kuzminsky: no good deed goes unpunished. your clever hal files foil emccalib, as rob__ just discovered. http://pastebin.ca/1354743
jepler: i got my little lathe running :-D
rob__: oh, and for posting the error message right away, you get a cookie
(about your lathe)
yeah, "great, now i have TWO machines i need to convert to cnc/emc2"
what lathe is this?
nothing that would excite anyone here :-/
a little 7x12
all manual, partly rusty ;-)
now you can make round things
have any parts you're itching to make?
rob__: I'll put a bug on sf about this, so at least it's not forgotten
and maybe somebody will come up with a good solution for it that I don't imagine right away
i just scratched my first itch and turned replacement feets for some backyard furniture that got knocked around in a wind storm a few months back
now my table is level again :-)
next up is a pair of pulleys for the never-ending belt-drive conversion for the mini-mill
jepler, setting setp hm2_5i20.0.encoder.02.scale [AXIS_2]INPUT_SCALE works ok it seems as u said
is it threadcutting?
it's got a carriage leadscrew geared to the spindle, so yes in theory though i havent tried it yet
i got a baggie of gears when i bought it
ah, then yes
if you're lucky and have all of them anyway
but i hope to not turn any threads until the cnc conversion is done ;-)
it builds character
hm so i dont think i understand what's up with the bug rob reported
rob__: ok, thanks for the report and I'm glad you could verify the workaround. I mentioned it in the bug report. https://sourceforge.net/tracker/index.php?func=detail&aid=2669566&group_id=6744&atid=106744
a gui that lets you change pid settings and then rewrites them "where they came from"
so it parses and rewrites the ini and/or hal file (I think)
I think it figures out what can be calibrated by regular-expression-based parsing of the hal file
but it interfaces to halcmd in a way that doesn't do the expansion of inifile stuff into parameter names
and i imagine it'd have a hard time emitting the un-expanded thing back to "where it came from"
or maybe not, i dont know
i think our config system belongs on the "needs work for 3.0" list
So I just got my Maxim SPI thermocouple chips. I think that I'm going to try to use the Hostmot2 RAW commands to read the chip for now.
Then maybe after I have figured that out I can add support to hm2
this is a very cool idea: http://www.datron.de/typo3temp/pics/f138d388ea.jpg
on the side of the spindle there's a probe which can be rotated in place to probe for the material position
after that it just swivels away, and it doesn't interfere with milling
yes that's cute
what's even cooler is the software it comes with to compensate for warped surfaces
datron, nice machines, rather have a matsuura ;)
good night all
MrSunshine__ is now known as sys2