Where do you mount the magnet on these encoders?
1-3mm above the center of the chip
on a spinning shaft?
hmm, I was looking for something for my spindle motor. That might just work...
skunkworks: was that reply to me?
the resolution goes down with RPM
the 8 bit one has a max rpm of 30k
but the number of counts its going to put out at that speed is lower in incremental mode
alex has done a lot of work in the interpreter - I just thought the word 'challenge' looked funny ;)
sounds like a miniature turret encoder
yep small/cheap absolute encoder also pot replacement
the best thing about getting old is you can watch your old favorite movies again for the first time
And you are always meeting new people...
if only I could remember their names
My spindle motor is connected to the actual spindle though a belt with a smaller pully on the motor, a larger pully on the actual spindle (2:1 - 18teeth vs 36 teeth). If I were to put one of these encoders on the bottom of the motor shaft, and knowing the ratio, would this be good enough to use to do rigid tapping? Or is it essential that the ecoder be on the actual spindle where the tool is?
skunkworks: "alex_joni" alex?
I'm happy, my twiddler module fits in a 5I20 even with 8 servo axis..
time to go home before I break something...
btw, the video at this link cracks me up. We have to have the pretty woman to grab our attention before the Senior Product Marketing Manager appears otherwise we might not watch ;-) http://www.austriamicrosystems.com/eng/Products/Magnetic-Encoders/Rotary-Encoders/AS5134
bait and switch :-(
bye add thanks Peter
cnc4pc has fancy looking pendants
wow new door seals on both ends of the Hardinge...
morfic I've used one of those
any longevity complaints? integrations looks easy enough even for a morfic ;)
[00:26:49] <JT-Hardinge> http://www.linuxcnc.org/docview/html//examples_mpg.html
I just tested it then set it to Ray but can't find him to get it back LOL
[00:27:23] <morfic> http://wiki.linuxcnc.org/emcinfo.pl?Hooking_Up_A_MPG_Pendant
i found this one
austria microsytems chick is pretty hawt
rofl at the marketing guys eyebrow
the one I linked is the one I wrote after testing the cnc4pc pendant
ah yeah, i read that link earlier too, i recognize the wording :)
dang forgot the space :)
* JT-Hardinge time for this old dog to hit the lazyboy and flip on the magnetass switch
boss looked at space on door of mori seiki, so pendants came up again
steel or the magnet would not work :P
say goodnight Gracie
$11 surface grinder... http://sfbay.craigslist.org/sby/tls/1747849897.html
I'd be in that
SWPadnos: Yo, you gots a sparez GPIB IO card?
apostrophe is now known as ApOsTrOpHe
I got the plotter!!!!
The guy used to work for HP, and this one unit is a pre-street version. Even came with 2 user manuals AND the SERVICE manual with diagrams, parts list, and I think schematics!!!
ries_ is now known as ries
ApOsTrOpHe is now known as apostrophe
what u after MattyMatt ?
MattyMatt: We really don't need to know about your order of blow up dolls!
these sets of vextra steppers
I'm up against 2 snipebots
ah well, back to work. all the 2A ones are gone now, except for the 5 phase ones but they've got 9 bids already
I don't have the time or money to figure out a 5 phase driver anyhow
I'll let pfred1 do that first :)
- i bought one of the 220Ncm ones, pretty cheap
yeah these sets were 4x equiv and 3x equiv, or maybe the slightly shorter ones
they went for 21gbp both sets
If I desperately needed better motors, I'd have pushed it up some more
but I just did a good day's milling yesterday with these ones
all cash must be saved for ballscrews :)
I'm gonna go for some of the slides this place have got tho
they've got one that might just be the rail I've got fitted already, which would be extra handy
this one is riveted to my ballscrew unit
bloody hell nobody sniped the 5 phases
26 gbp for 4x nema 23 , a 2A 5P, 1A 5P, 2a 2P & 1A 2P
a nice selection
MattyMatt: seen linearmotionproducts2008?
on ebay, pretty cheap
for new ballscrews and slides made to measure
[09:26:16] <Valen> http://shop.ebay.com/linearmotionbearings2008/m.html
not too shabby :)
a single round rail wouldn't do for a quick fix for my flex tho, I'd need to ditch the drawer slide at the top
or turn it 90 deg, so it's stiff axis is tangential to the round rail
these drawer slides are great, but in only one axis
how do people use drawer slides for CnC stuff?
well strictly the drawer slides only work under the table, where they can extend
the others are similar construction, but have a 100mm carriage in 300mm ballrace in 500mm slide
the work OK if you use enough of them
and they are dirt cheap
I'll have figures for flatness of travel, when I can afford a dial gauge :)
and a straight edge
the steel ruler I'm using wouldn't be smooth enough for a dialgauge I don't think. pita aligning it anyhoo
anyway, the drawer slides under the table are the least of my worries on this machine
they do need a lot of support. mine are on 3x3" beams
1/4" angle iron would be better
MarkusBec_away is now known as MarkusBec
anyone tried the hawkboard ?
looks similar to beagleboard, but cheaper?
I haven't looked at the difference between the OMAP L138 and hte 3530(?) on the beagleboard, but otherwise they look prett ysimilar
there's a blueboard also...
should you get all of the ubuntu updates after installing the live cd?
in general, yes
jlmjvm: I don't think there is much critical for emc2 use in the updates, but they don't hurt...
hawk is pretty low power
beagleboard: BogoMIPS : 378.14
here's another beagleboard: BogoMIPS : 500.97
yeah, I did notice the half clock speed
and the CPU is a bit more dumb for the hawk
but at today's prices, I think the D510 is the winner in the hawk/beagle competition :D
wow. I ordered some stuff from NewEgg yesterday (including one of those Jetway boards with 12V-only power), and it's arriving today
with no special shipping charges
let me know how the jetway is
since you can get an entire PC (including disk and memory) for the price (but not the size and power consumption) of the beagle
if your going down the minimalist route perhaps that group that had an AVR running gcode is the end result
total cost ~$4
SWPadnos are the jetway boards atom based?
I believe the new atoms with the non 945 chipset are pretty power efficent
[12:28:11] <SWPadnos> http://www.newegg.com/Product/Product.aspx?Item=N82E16813153166
yeah thats an older one, still has the chipset fan
this one is more expensive because it only needs 12V DC power
going for car battery UPS? ;->
I don't think it's all that old. the D510 hasn't been around too long
oh its not "old" as such
its just not the new new stuff lemme see if i can find one
yeah, the NM10 chipset was only released last December
the AVR stuff?
note that the subset of G-code that is supports is - erm - quite a *sub* set :)
ill go check it... thanks (to check is it good or not)
if you limited the post processor to G1's that wouldn't actually hinder much it seems
most of post processors seem to just spew gobs of G1s and thats it
that makes block processing rate become more important
you can get AVR's up to 90Mhz I believe
you can make them in FPGAs, but you can't buy them that fast (that I know of)
not the 8-bit ones anyway
not 8 bit no
interresting to investigate
[12:34:00] <Valen> http://www.atmel.com/dyn/products/param_table.asp?family_id=607&OrderBy=part_no&Direction=ASC
with built in USB
[12:34:20] <Andy_M> http://www.planet-cnc.com/index.asp
yeah, but those aren't $4 ;)
128kb of ram and half a meg of flash
built in USB and ethernet, even
check this... its a RS232 with 115mbps actually
SWPadnos: yeah those 90mips ones are $8
around 20khz of stepper...20k step/sec
get one with a bunch of PWM outs on it and you are 90% of the way to a 4 axis machine and a total cost of < $100
now thats interesting
yeah, the AVR32 is a good candidate for some of the low level stuff
and that's not $8 system cost, it's $8 for the CPU ... :)
(in 800 qty)
at, one of htem is only $5 in 1000 qty
its an all in one device you only need to give it (a little bit of ) power
and a bunch of caps, I/O protection, a PC board, etc. etc.
which you need anyway on the driver
ok lets be generous, $12 for the AVR ;->
you could still create a 4 axis setup for < $100
sure, you could do that
for say 400W motors (i'm thinking servo here)
I'm not saying its the best
but a mesa tool chain is $500 for the same thing, its a bit of a barrier to entry
it's not the same thing
no, but it might be close enough
it may perform enough of the same functions, in some cases though
I guess I should mess with my AVR32 development kit today
one of the UC3A-based ones anyway
I'm thinking of making an open source mill based around graphite epoxy, the whole idea being you start with a good bed, and a minimal set of other bits, then you can upgrade them as time/money allows
I got a dragon yesterday
desigining a breakout board for it tommorow, and learning C on friday lol
anyway nighty night
ok, good luck
with the difference that you can get running with the mesa toolchain in a couple days/weeks
vs. weeks/months/years? for the avr stuff
yeah. there's still no floating point unit in the AVR32 (but they're working on adding one)
and the atom-boards from intel are cheaper than a beagle/hawk...
note once you add memory, power supply, and disk, but they're still close
dang internet is lumpy today
wow. Atmel now makes a 6-pin microcontroller in a SOT23 package
mine is finally fine :D
and an 8-pin UDFN (about the same size), if you need more I/O :)
[13:42:47] <SWPadnos> http://www.atmel.com/pressroom/photos/ATtiny.jpg
SWPadnos: remember the strange problem with emails I had?
wasn't it called "Outlook"
nope... it was some strange transmission problem
data arriving garbled
it seems there was a defective optoswitch
oh right, the jpegs that wouldn't email or something
anyone know where I might find hal and ini config for steppers in velocity mode with PID to start from?
actually there's a user who uses that setup, but I don't remember which one
google wasn't overly helpful
grommit: most likely you'll have to start from a servo-sim config
and add stepgens to it
gtom is the first I think (Sebastian had to make some changes to accommodate his setup)
but steppers in velocity mode with pid aren't really gonna work well imo
pcw_home: for mesa hardware?
yes, and I have mesa hardware
well then, it's sorted ;)
grommit: at least you know it should be doable .. which is a huge step forward
I think gtom had linear scales for feedback and wanted to retain their accuracy
Anyone know gtom's email address? Or should I just post to the list in hopes of rousing him?
he hangs out on the forum a lot grommit
ok, I'll keep an eye out for him
You might search through the forum postings, his original machine setup questions are there
[13:52:01] <SWPadnos> http://www.linuxcnc.org/index.php?option=com_kunena&Itemid=20&func=view&catid=10&id=286&limit=6&limitstart=36&lang=polish
err, I guess you don't need the "lang=polish" :)
neither do I, come to think of it
cutting left hand threads with g76 is it as easy as just having the start Z on the left side of the end Z? It seems so on a sim...
Yea! that makes it easy
thanks for the links...
ok, this is weird. http://qurl.org/fz0
but I want to see how it tastes ;)
hi all , is there ready distribution of 10.04 and emc 2.4?
09:44 < SWPadnos> wow. Atmel now makes a 6-pin microcontroller in a SOT23 package
is it actually available yet?
and close to the pic price?
[14:16:40] <renesis> http://search.digikey.com/scripts/DkSearch/dksus.dll?Cat=2556109&k=attiny10
tiny10 = does not exist
and the small pic is like half the price, dunno part number or exact spec though, been around way longer so safe to assume atmel put more mem and flash
damn only 12mhz too
o, right because internal RC is maybe only option, only practical one
right, they're flash parts
1K prom is pretty good
32b of sram is kinda weak, but enough
plus 32 registers :)
yes i know
16 are gimp tho
the last 3 pair make up for it tho
ive done a ton of avr asm =)
you can still do all the math and stuff with them, just no immediate operands
yeah, me too
i did the 2.4 upgrade,cant connect to internet anymore
my fav architecture so far
I have a project that's got ~800k of AVR ASM source
sam7 is neat, good atmel docs, but the dev tools mess kinda killed it
jlmjvm, 2.4 and internet are unrelated I'm sure
I have a few dev kits but never got around to making anything with the SAM7x series
i spent some time coding peripheral interfaces
i agree,but it has done it 2 times
just to learn c
what do you mean that it has done it two times?
two machines upgraded, or two times you've tried to connect to the internet (on the same machine), or something else?
like after youve compiled two times?
both times that i upgraded to 2.4 i lost internet
had to reload the os
did you also update all other packages?
wow shotgun fix
Out for Delivery!
hopefully atmel can keep tiny10 in stock soon
are the 10's actually out?
im afraid to do anything with it because what if i do something cool and need way more
iunno, theyre not in stock at digikey
have you seen one in real life?
jlmjvm, did you update the same machine twice?
but avrisp2 and dragon and xmega (and avr32 but who cares) and some avr have been like this
like theyll be sporadically stocked at first
ok, next time, do all OS updates and see if you still have internet access *before* updating EMC2 to 2.4
did that this morning
ok, and it works fine with everything up to date except EMC2?
exactly what did you do to update to 2.4?
and what OS version are you using?
the wiki instructions
the last live cd
btw,got 2.4 to work also
atmega: arrow lead time says 10 weeks
and all you did was edit the sources.list to change emc2.3 to emc2.4?
damn they been hyping this chip forever now, theyre lagging
what was the fix?
yes,then reload and mark all
when you did that, was anything other than EMC2 updated?
i think so
like the RTAI kernel, or more stuff
dunno for sure,seems like it had some dependecies
well, the way to tell for sure is to install the OS, run synaptic, reload package lists, mark all/apply, then change the package repo name and update emc2
just wanted to report what happened,will reload os and go back to 2.3.5
issues with 2.4?
possibly just a driver issue?
[15:43:29] <grommit> http://www.youtube.com/watch?v=j1kftCx5-tA
good morning. the 2.4 version not is out ?
well, that's a bummer. the NewEgg description of the Jetway MB is wrong. There are only 3 USB ports on headers
3 as in 3 double for total 6?
no, that's what the description says
never seen a usb header with anything else then two ports on it
it's actually one 9-pin dual-port header and one 4-pin single port header
I have :)
Rip apart a hub and shove it in there
i've at least heard of it (now) :)
yeah, me too
I hadn't seen one before today
LOL, Playboy in 3D
it has 8 GPIO pins on a header (with Vcc and Gnd also), which is cool
that's in addition to the parallel port
some mini-itx board?
[15:55:27] <SWPadnos> http://www.newegg.com/Product/Product.aspx?Item=N82E16813153166
gpio and sometimes spi seems fairly commmon on those
yep, way more common than on an ATX mobo
cool. it's got an RS422/485 port as well (TX and RX differential pairs only though, no modem control signals)
one board i looked at when i was shopping for mini-itx, i think it was a jetway too, had four headers for serial ports, all rs232/422/485-capable
hmmm. it looks like this extra 4-pin header is actually part of COM2, but you can select RS422/485 or RS232 for that port in the BIOS
SWPadnos: Yo, joooos gotz a sparz GPIB IO card?!
nope. I gotz no GPIB card
Really?! Not even one?
nope. never had one
Ive got a QBUS one...
SWPadnos: I gots me a HP 9872C Flat Bed Plotter =)
I saw that
I saw an GBIP to ethernet adapter, but it's $200
I have qbus machines :(
that's cheap. they used to be $1000
The Indel D510MO mini-itx is a nice board (fanless): www.mini-box.com/Atom and it's only $80.
yep. still has only 3 USB headers (3 ports), which is a problem for me but not many others
SWPadnos: Go get a 8 port usb hub
the main difference is that the Intel board needs an ATX power supply, but the JetWay only needs 12V in
[16:05:51] <SWPadnos> http://cgi.ebay.com/NATIONAL-INSTRUMENTS-NI-PCI-GPIB-IEEE-488-2-CARD-/280506143249?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item414f781211
true but that power supply is tiny!
it's $30 or more, closer to $50 for a PicoPSU (which still needs the 12V supply)
has the correct specs on your board, fwiw...
so do I, now :)
SWPadnos: Doesn't look like a GPIB connector to me... http://sfbay.craigslist.org/sby/sys/1746584263.html
that's not a GPIB connector
it looks like the description is for two cards but only one is pictured
I emailed him, we'll see.
SWPadnos: Yeah, I even got the service manual too.
yep, that's cool
Man, they SERIOUSLY did some awesome documentation back then
PN, vendors, drawings, etc
is there rt kernel for ubuntu 10.04?
SWPadnos: A mobo with RS422 built in?!
only one port though, and it's just RX/TX that change, the other signals are left as single-ended RS232
anyone have a favorite source for inexpensive, small 5VDC supply (110AC in, 2A or so)?
My junk box
10GBase-T is on its way. Too bad fibre is faster and less expensive ;)
send one over
grommit: I'll fax it to you
Radio Shack isn't all that bad, but I don't know if they still have a 2A model
SWPadnos: You'll get raped on any walwort these days
walworts max at 1A, I believe
marlin p jones has power supplies, or midwest surplus
elmo40: Nope, I have some 5A ones (switchng)
that's because wallworts can be used to make beer, it's the alcohol taxes
wall warts on the other hand, are a dime a dozen
Jymmm: walworts? interesting.
out of all of mine I have seen a max of 1A @ 12V
elmo, do you care if it's switching?
ahh, fibre networking... 100Gb/s <drools>
I don't think I've seen any that plug directly into the wall that are higher than about 2A, but there are definitely a bunch that have cords that are several amps (I have a 5V 5A one from a DSP development kit)
eric_unterhausen: I am not looking for one ;) only making a comment
but it's more like a laptop power brick
I want to mount it to a plate inside a chassis, so would rather not have a wart
if I wanted 5 or 12V I would rip apart a computer power supply :)
I save every walwort I come across anymore. At $15/ea just too expensive not to.
could do that, I might have some junk around...
then you should get a DIN-rail mount one, but you'll have to give up "inexpensive"
Jymmm: $15? wow, that is expensive. the local surplus place here has them for $2 - $5
I saw those, and they do look nice, but yes, not inexpensive
[16:28:31] <SWPadnos> http://www.radioshack.com/product/index.jsp?productId=2049709&filterName=Category
unless you mill the DIN rail clips into your one
close enough maybe? (6V 1/8A, $1.47)
It's being doscontinued
of course. get 6 :)
nokia phones are 5V, but iirc 700ma is the biggest I've seen
Any time you see a RS price ending in 7 or 8 means it's discontinued and clearance
my local RS stores say they don't have that one...
I got an usb/ide adaptor that came with a neat 12/5 psu
[16:34:17] <SWPadnos> http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=945-1075-ND
funny i was just searching digikey
[16:35:20] <SWPadnos> http://search.digikey.com/scripts/DkSearch/dksus.dll?Detail&name=285-1745-ND
that may be closer to what you're looking for
higher power than you need though
SWPadnos is the DigiKey search King!!!
come on, they only have 362000000 part numbers ...
Their search sucks
I love it
goto the main page and at the top type in "LED"
hmm. actually I should use that power supply in a project I'm doing
farnell search <3
Jymmm, yeah, and then select what kind of LED-related thing you want
SWPadnos: a fan!?
Oh yeah, a rivet has an led
drivers? backlights? LCDs? SMT LEDs? ...
No go look it brings rivets
so, you know you don't want rivets (or buzzers, battery holders ...)
so don't click those categories
so if I serach for LED, dont' show me rivets damnit!
type Diode :P
* bill2or3 searches for "not rivets"
Nah, I just tell SWPadnos and let him search for me
but what if the rivets are "dimpled" or something? :)
does it have/hold an LED ?
and intended to do so?
clearly you don't understand what text search is ;)
I clearly understand they didn't consider such a simple search
of course, I don't actually see the text "led" in the descriptions :)
I guess I don't care if they show me more stuff than I'm looking for at first, since it's so easy to narrow it down later
ah, Nylon, Glass fil[led]
No, what that is a is a general category listing. They use that as the default when the search exceeds a certain count, like 10K+
it still only lists items that match your search
there are 5 rivets that have the text LED somewhere in their data
"these rivets led to my demise"
well, I looked at one of the descriptions, from the list of 5 items presented to me when I clicked "rivets"
if I search for "rivet", there are 366 items in the "Rivets" category
so clearly they are using my search text
and there are 61K for 'led'
they have a shitload of different LED part numbers
try "cap" or "res"
No, you show me. I search for LED you dont give me rivets bastards!
"Chip Resistor - Surface Mount (210,861 items)"
searching for "res"
you could also type more, like "red led"
probably best is to include the package name in the search
or something like that
yeah, that's a big help
Maybe I don't know what color I want, maybe I want to se what's available, give me a list and then I can narroow it down from there.
I guess it's the difference between an index and a menu. DK is a very easily searched index, but it's not a menu
Jymmm: try farnell.com to see what's available and then search other places for the cheapest price :-)
that's what i do
also mouser.com has a similar index
the best search would probably be a combination of McMaster and DigiKey
McMaster has a nice visual menu, but DigiKey lets you select multiple categories simultaneously
combine those and it would be a real winner
Y'all are just WAY TOO COMFORTABLE with mail ordering stuff
it keeps the mailman employed
* MattyMatt drops litter
and that keeps the sweepers in work :)
digikeys site feels like a return to the 1990's to be honest
ans while that can be good in a lot of cases, that's not what i had in mind now
somebody on #reprap wanted to know a plastics supplier in EU, so I suggested his local yellow pages
DaViruz: or 1890's =)
Here's a great line from a power supply manual:
After it delivers it, I will repair three years free of charge for an
emergency breakdown. However, because handling is careless, it becomes for a fee.
"The short-circuit leaving for a long time doesn't cause the breakdown and do not do, please."
wow, usually you can at least make out what they mean
I still haven't had my Machining In Polsk lesson from yoyoek yet
I think I'll convert all his GUI to poloish, and see how he likes it :)
actually a careful read of his docs will probably give me the clues I need
and I have ballmills now, so I can try it out for real
3 ballmills and 2 eyeballs, despite my efforts today. These 2 flutes don't crush their way through anything like the 4 flute does
SWPadnos: my favorite bizarre translation from a power supply was for a redundant supply for a server which claimed that "when both supplies are working properly they will go Dutch the loading"
wooden shoes in a PS ???
heh - go dutch - that actually makes sense.
first thing I'm making when I've got 5 axes
MattyMatt: Um, why?
MattyMatt: Now, if you WEAR them, send us pics!!!!
I'll need them if I start casting
I had a good pair of boots that both soles fell off, together on cue. I just need wooden soles on them
WTF?! you cn't put "Entry level" and "Ninja" in the same job desc. The cheap bastards! http://sfbay.craigslist.org/sby/mar/1748857871.html
they are spammers, after all
"Root Beer Pong" ?!
it's a student drinking game
I know what it is, but it aint with root beer!
so, lying spamming bastards
$40k a year? I'm there dude
* MattyMatt returns after a year
Well, they do say it's a marketing job, I guess they are trying to sling their own shit, but it aint sticking to the wall!
they paid me these 5 beans, but they said they are magic
MattyMatt: No it's $30K-40K
DIRECT marketing, aka spam
No, I think it's door-to-door sales... http://northerncaliforniagroup.com/FAQ.html
like pizza flyers
junk mail is spam, IMO
multi-level marketing, i.e. a pyramid scheme most likely
1. What does The Northern California Group do?
We are outsourced by major clients to increase their market share through the acquisition of small to medium size business customers on their behalf. We meet directly with these customers, and through face to face, relationship oriented sales, are able to consult their business needs while increasing our clients customer base.
the business business
this is why I like internet shopping, it cuts out middlemen
MattyMatt: But when you have a problem, there's nobody to strangle!
is there a doco how to compile emc2 on a ubuntu 9.10karmic amd64 only axis no realtime?
M.I. Squirrel http://v6.tinypic.com/player.swf?file=sloeix&s=6
yep, just follow section 2.4 and 2.6
[18:16:44] <sealive> http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?Installing_EMC2#Building_emc2_simulator
this is what iam searching for
but i made a big miss
iam on karmic and a did delete the python2.5
now i'am in big trouble
sudo apt-get install --reinstall python2.5
(or something like that, look at the man page)
apt does use python 2.5
so iam pisst off as the americans say
german Da beist sich die katze in den schwanz
somewhere in /var/apt/cache or similar will be the packages you have installed
go there, then use dpkg instead (which may not depend on python, but I don't know)
dpkg -i <the name of the python package>
i go to ubuntu and see what i can do
you are wright dpkg does not use python
synaptic may also be able to do it
especially if you use the CD-ROM as a package source
synaptic wars the first that colust
thet went off
ok i try
Hi, I want to be able to use G76 canned cycle threading on my little 7 x 12 retro'd lathe. I have an open loop stepper system with emc2. Is all I need just a spindle index pulse? I'm guessing that a spindle encoder signal would be useless in the case of an open loop stepper system. Is that right? - TIA for anyone's help!
some one correct me if I'm wrong, but I think you need an encoder signal all the way around
EMC will slave the motion of your X axis to whatever the spindle is doing
the fact that X is open loop really doesn't matter
you can use an index pulse only, but an encoder is better
the type of axis motors you have is irrelevant
did you use stepconf to set up your machine?
So the z motion will thrack variations in spinde speed regardless huh? I think I get it now.
yes, you get better synchronization the better the encoder resolution
and 1PPR is pretty low resolution :)
HAha yes it is.
ok, you can select a parport input as "Spindle encoder phase Z"
I don't think there's an option for phases A and Z, but if there is, that's a better option to use
assuming there isn't, you need to add something like the following to your custom.hal (and make sure the checkbox to use a custom hal script is checked)
net spindle-phaseZ encoder.0.phase-A
setp encoder.0.counter-mode 1
(that may be called count mode, and the signal may not be called spindle-phaseZ, you'll need to check those)
oooh. I may get dropped here, back in a bit if so
I think I found the right doc for this: http://www.linuxcnc.org/docs/devel/html/examples_spindle.html#cha:Spindle-Feedback
yep. using stepconf will add a lot of that for you
OK. I think I will try and make an encoder. I checked the price of one online, $300 - $500 - that seems awfully high. Any suggestion for a cheap ready made one?
or, if you can make a 1:1 belt drive (absolutely must be 1:1, you can only have one index per revolution), you can use the AMT-109
available from DigiKey
$29 or something
why must it be 1:1?
because you may only have exactly one index per spindle revolution
[19:33:11] <SWPadnos> http://search.digikey.com/scripts/DkSearch/dksus.dll?Cat=1966131&k=amt
Awesome. I have plenty of gears on the back available with room to add a jack shaft and encoder. I guess I'd just need a litthe friction to eliminate backlash - does that sound ok to you?
reason I ask is that I have a 2:1 belt on a spindle and wanted to put an encoder on it, but there is only room to put it on the spindle motor shaft, and not the actual tool spindle running at 1/2 the motor speed
a small belt drive would be fine. just make sure you use only the final spindle gear, you can't base the index off some other ratio
grommit, that won't work well for threading or other spindle synchronized motion
you could always gear the encoder down by 2:1
so it's the same as the spindle
oh, hmm so it isn't on the actual spindle but it on a phantom spindle, as it were....
but I'd only do that if the spindle is driven from a gear/tooth system, not any kind of friction system that might slip
It is a friction system, and I suppose it could slip (belt)...
right, the requirement is that the index happens once per spindle revolution, if you gear it 2:1:2, that should be fine
ok, then it's not a great idea
until it slips
it'll probably work fine most of the time, but it's the times it doesn't work that you really would have needed it
right! for threading.
for threading when the load on the spindle causes some belt slip
back to the drawing board on that one (again)...
any kinds of encoders that fit on tool holders?
none that I know of
except a tach
market opportunity :-)
Someone said that tachs wouldn't be accurate enough to do tapping
you need an index pulse, and it's ideal to have better resolution, such as an encoder would provide
but you can use a single index "flag" and an optical detector if you want
or a laser on a flat spot, like a tacj
you don't want to use the tach itself, but you can use the method they use to get your index pulse
So I would have 1ppr.
if you don't take massive cuts, and/or you do several finish passes, you should get reasonable results
[19:43:30] <davidf> http://members.shaw.ca/swstuff/spindle-encoder.html
SWPadnos, I have a gear right on the spindle I can use. As for backlash, does G76 ever have to reverse the spindle direction? If not, just a little drag on the encoder should eliminate any backlash issues, right?
no idea :)
I don't think a lathe spindle ever gets reversed in a canned cycle, but I wouldn't bet you dinner on that
(just because I don't know, not because I think reversals are common)
OK. If I have to, I can add a timing pulley and belt.
you may be able to use the gear directly, incidentally
similar to this method: http://pico-systems.com/bridge_spindle.html
Yeah I thought of that, but it is only like 40 teeth. I guess I could get 160 ppr with quadrature though...
40 is way better than 1
at least 40 times better! :)
hmm, that link gives me some ideas for my drawing board...
Just looked at that gear encoder. Very cool. Are those sensors magnetic?
yes, I think those are (the ones Jon E used)
For high quality 40 TPI threads any opinion as to how many counts per rev would be enough?
as many as your hardware can count...
at the speed you require...
that's a hard question to answer. it depends on how beefy your spindle is relative to the cuts you expect to take
SWPadnos: another smallish 5v pwr sup. reasonably inexpensive: http://www.trcelectronics.com/Meanwell/rs-15-5.shtml
oh. nice one
SWPadnos, so the main thing is light cuts mean less perturbation of the spindle speed which means I can maybe get away with lower resolution? Do I have a handle on this?
yes, I think so
just make sure to use the position-estimate output from the encoder, not position
What is that, a HAL thing or a hardware lead thing?
position-estimate output from the encoder??
the encoder counter has a position output that only tracks actual encoder state changes
and another output that estimates the current position, taking into account the timing between the last detected edge and "now"
you need the less lumpy one, the estimate
This is in software, right?
yes, it's the use of one HAL pin instead of another
SWPadnos, what a lot of helpful stuff. Thanks!
Dude, it's called sandpaper, paint, and dont leave it in the back of your truck in the winter time! http://sfbay.craigslist.org/sby/tls/1749284288.html
or even 1 minute with a pressure washer